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Optimization and Process Effect for Microalgae Carbon Dioxide Fixation Technology Applications Based on Carbon Capture: A Comprehensive Review

School of Artificial Intelligence, Beijing Technology and Business University, Beijing 100048, China
School of Water, Energy and Environment, Cranfield University, College Road, Cranfield, Bedfordshire MK43 0AL, UK
Author to whom correspondence should be addressed.
Received: 23 February 2023 / Revised: 13 March 2023 / Accepted: 14 March 2023 / Published: 16 March 2023
(This article belongs to the Section Carbon Cycle, Capture and Storage)


Microalgae carbon dioxide (CO2) fixation technology is among the effective ways of environmental protection and resource utilization, which can be combined with treatment of wastewater and flue gas, preparation of biofuels and other technologies, with high economic benefits. However, in industrial application, microalgae still have problems such as poor photosynthetic efficiency, high input cost and large capital investment. The technology of microalgae energy development and resource utilization needs to be further studied. Therefore, this work reviewed the mechanism of CO2 fixation in microalgae. Improving the carbon sequestration capacity of microalgae by adjusting the parameters of their growth conditions (e.g., light, temperature, pH, nutrient elements, and CO2 concentration) was briefly discussed. The strategies of random mutagenesis, adaptive laboratory evolution and genetic engineering were evaluated to screen microalgae with a high growth rate, strong tolerance, high CO2 fixation efficiency and biomass. In addition, in order to better realize the industrialization of microalgae CO2 fixation technology, the feasibility of combining flue gas and wastewater treatment and utilizing high-value-added products was analyzed. Considering the current challenges of microalgae CO2 fixation technology, the application of microalgae CO2 fixation technology in the above aspects is expected to establish a more optimized mechanism of microalgae carbon sequestration in the future. At the same time, it provides a solid foundation and a favorable basis for fully implementing sustainable development, steadily promoting the carbon peak and carbon neutrality, and realizing clean, green, low-carbon and efficient utilization of energy.

1. Introduction

With the abundant use of fossil fuels, the excessive emission of greenhouse gases, especially carbon dioxide (CO2), has brought serious ecological damage and climate change to human society, and global warming has become a major problem to be solved urgently [1,2,3]. The impact of greenhouse gas accumulation is long term, with the average global temperature expected to rise by 2 °C by 2100 and 4.2 °C by 2400, which will cause great economic losses and be a global threat to food and nutrition security [4]. In China, the average crop yield loss is 2.58% with a temperature increase of 1 °C [5]. The CO2 concentration increased to 2.46 ± 0.26 ppm/y in October 2021. If no measure is taken to control its development at the earliest convenience, the CO2 concentration may reach 667 ppm in 2100 [6]. Therefore, global efforts are being made to mitigate climate change through reducing the CO2 emission and/or enhancing carbon sequestration, which are crucial to long-term sustainable human development goals [7]. Reducing the use of fossil fuels is the straightforward way to reduce CO2 emissions. Further, a strategy of carbon capture, re-utilization, and storage to reduce CO2 emissions is the most common technology for the moment [8].
Carbon capture and storage can meet the expanding worldwide energy demand by converting the captured CO2 into fuels or using it to enhance the recovery of oil while dramatically lowering CO2 emissions [9,10]. At present, common methods of CO2 fixation include physical, chemical, and biological fixation methods [11]. For instance, the physical method is to inject CO2 into the deep sea or geological layer to temporarily bury it, which cannot ensure that CO2 will never escape due to the constraints of the geological environment, space, and cost [12]. The chemical method uses an adsorption material to directly fix or add alkaline neutralization reagent in the form of carbonate or bicarbonate to fix CO2, which is relatively safe and permanent, but has the disadvantages of large reagent dosage and high cost [13,14]. The biological fixation method utilizes the photosynthesis of green plants to convert CO2 into organic matter in the plant, provide energy sources, and maintain the C–O balance of the atmosphere. Of these, the biological approach has been deemed the most economically feasible, environmentally friendly, and sustainable method to capture and store carbon. Plants, microalgae, etc., are commonly used for biological carbon sequestration. In a general way, plants reduce carbon emission by only approximately 3–6%; but when grown under ideal conditions, microalgae such as cyanobacteria and green algae could be 50-fold more effective [15].
Yahya et al. studied the potential of microalgae as biological carbon fixers to support the development of a circular economy and environmentally sustainable coal-fired power plants [16]. By optimizing the culture parameter settings, Dasan et al. accelerated the CO2 fixation efficiency of Chlorella vulgaris [17]. Premaratne et al. evaluated the CO2 storage potential of Desmodesmus sp. in flue gas under nitrogen element limitation conditions, and applied the resultant biomass to biofuel preparation [18]. Ding et al. found that using native microalgae species to reduce effluents in palm oil mill and industrial discharge of CO2 is an effective strategy [19]. To sum up, microalgae are a superior candidate for carbon capture and storage, which can also be utilized in biofuel production, wastewater treatment and other industries.
Microalgae with a simple structure, a short growth cycle, wide distribution, strong adaptability, and higher photosynthetic efficiency than conventional crops are mainly composed of eukaryotic and prokaryotic microalgae [20]. Microalgae directly use solar energy to fix CO2 and produce O2 and secondary metabolites, which is a typical representative of carbon sequestration organisms [11]. This process is also known as photosynthesis, including the primary reaction, electron transfer, photophosphorylation, and carbon assimilation (i.e., CO2 fixation and formation of sugars). Because all crop biomasses obtain carbon from it, as shown in Figure 1, the Calvin–Benson cycle (C3 cycle) plays a major role in the CO2 fixation pathway in nature. Although land plants can also absorb CO2 and produce organic matter through photosynthesis, microalgae can be planted in seawater or wastewater, can capture CO2 from various sources, do not compete with traditional agriculture for soil resources, and achieve CO2 fixation 10–50 fold more efficiently [21]. Every 1 g of biomass produced by microalgae can fix 1.83 g CO2 [22]. Microalgae biomass with a high application value, which includes lipids, proteins, and polysaccharides, can be used as raw materials for biofuel, biochemical, food, medicine, and other industries. The species and environmental conditions of microalgae affect the photosynthesis and carbon sequestration efficiency of microalgae, which is beneficial to further effective utilization of microalgae [23].
In recent years, more and more reviews have focused on the influence factors and applications of microalgae CO2 fixation technology, but there are few studies on the comprehensive analysis and discussion of microalgae based on the mechanism of carbon sequestration. Raeesossadati et al, mainly discussed the effect of important factors such as CO2 concentration, photobioreactors, temperature, and light intensity on microalgae CO2 fixation [24]. You et al. reviewed the application of wastewater treatment by microalgae [25]. By reason of the foregoing, based on previous studies, the optimization prospects and process effect of microalgae CO2 fixation technology are comprehensively reviewed as shown in Figure 2. Firstly, the mechanism of CO2 fixation in microalgae is reviewed, and the main factors affecting carbon sequestration and growth are analyzed. Then, how to use strategies of random mutagenesis, adaptive laboratory evolution (ALE), genetic engineering to screen microalgae species that can improve the photosynthetic efficiency and the production of by-products is discussed. Moreover, combined with the current challenges faced by microalgae carbon sequestration technology, the application of microalgae carbon sequestration technology in CO2 emission reduction, wastewater and flue gas treatment are analyzed. In the future, it is expected to establish a more optimized mechanism of microalgae carbon sequestration, which provides the reference for large-scale industrial application of CO2 fixation in microalgae and the environmentally friendly economy in China.

2. Mechanism of Carbon Dioxide Fixation Technology by Microalgae

2.1. The Photosynthetic Carbon Metabolism Pathway

In essence, the photosynthesis of microalgae is a mechanism that allows them to utilize solar energy to exchange materials and energy with their surroundings and turn CO2 into glucose [26]. It can be expressed by Equation (1):
C O 2 + H 2 O C H 2 O n + O 2
Photosynthesis is also divided into the photoreaction stage of converting the light energy into the active chemical energy and the dark reaction of converting the active chemical energy into the stable chemical energy. The dark reaction requires the strong reductant (NADPH) and the energy (ATP) generated by the light reaction to immobilize and reduce the CO2 to sugar, as shown in Equations (2) and (3). The light energy is converted into chemical energy to resolve NADPH into NADP+ through the photosystem of PSII and PSI. The pH gradient was produced on the thylakoid membrane and was applied to synthesize ATP [27].
H 2 O + A D P + P i + N A D P + light O 2 + A T P + N A D P H + H +
C O 2 + A T P + N A D P H + H + C H 2 O + A D P + P i + N A D P +
Photosynthetic carbon metabolism in microalgae is mainly dependent on the C3 cycle [28]. By employing ATP as an energy source, lowering the energy level, depleting NADPH, carbon enters the C3 cycle as CO2 and exits as sugar. This is what we see in Equation (4)—the C3 cycle is simplified to carboxylation, reduction and regeneration of ribulose-1,5-bisphosphate (RuBP). RuBP entering the carboxysome is bound to CO2 by the ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) enzyme, which subsequently converts to a 2 molecules 3-phosphoglycerate (3-PGA) and diffuses from the carboxysome to the cytoplasm through the pores of the hexamer shell protein. Equation (5) shows the reduction phase, where 3-PGA in the cytoplasm forms glyceraldehyde-3-phosphate (GAP) catalyzed by the enzyme. The regeneration of RuBP ensures the continuous operation of the carbon sequestration cycle.
3 R u B P + 3 C O 2 G A P + 3 R u B P
P G A + A T P + N A D P H + H + G A P + A D P + N A D P + + P i
The rubisco has the dual functions of oxygenation and carboxylation, specifically which the choice of function is influenced by CO2 and O2 concentrations. Due to the relatively high concentration of O2 in the atmosphere, it is conducive to the work of oxygenase and promotes photorespiration, which leads to the reduction in photosynthesis production. Therefore, microalgae have developed CO2-concentrating mechanism (CCM) to maximize photosynthetic efficiency under low CO2 concentrations or inorganic carbon (Ci) conditions [29].

2.2. Carbon Dioxide Concentrating-Mechanism

When CO2 is dissolved in fluid, it exists in four specific Ci forms: HCO3, CO32−, H2CO3, and dissolved CO2. The proportion of Ci varies with pH. It’s possible that different microalgae strains prefer various Ci types. For instance, Nannochloropsis oculata can only actively transport HCO3, and Chlamydomonas reinhardtii be able to use simultaneously CO2 and HCO3 [30]. In truth, pH 7.5–8.4 is the typical range for the culture medium used by microalgae. Approximately 90% is HCO3 in this culture medium, and the concentrations of CO32− and H2CO3 are low [31]. In the process of acclimatizing to the concentration of Ci changes in the environment, the microalgae have formed CCM that can help to adapt to the changes in the external CO2 concentration. CCM is based on a single cell, which can actively transport and accumulate Ci at low CO2 levels by counteracting the inefficiency of rubisco to boost photosynthetic efficiency. It is found in almost all eukaryotic microalgae and cyanobacteria and plays a crucial role in the fixation process of carbon [32]. In both eukaryotic and prokaryotic, the CCM of microalgae includes three main systems: (1) Ci transporter; (2) Carbonic anhydrase (CA) that is used to convert Ci to CO2; (3) microcompartments with rubisco for the delivery of CO2 [29]. Microalgae concentrate the Ci pumped into the cell at the photosynthetic site to form high carbon sites nearly a 1000-fold higher than the surroundings, and convert them into organic carbon through the rubisco to achieve the carbon fixation [28]. This is also regarded as the rate-limiting step of the entire cycle. Rubisco in the pyrenoids of eukaryotic algae or in the carboxysomes of cyanobacteria has a low affinity for CO2 and requires higher concentrations of CO2 to obtain a normal rate of reaction [33].
The simplified model of CCM is shown in Figure 3, which is mainly divided into two stages: The first stage involves obtaining Ci from the environment and delivering CO2 and HCO3 to the chloroplast; in the second stage, Ci crosses the thylakoid membrane and is reduced to CO2 by CA at higher ambient pH, which increases the concentration of CO2 near the rubisco and ultimately enhances the photosynthetic rate [32]. HCO3 can enter cells through active transport, while CO2 can enter cells through inactive diffusion in microalgae. CA regulates CO2 and HCO3 to maintain proper pH in the chloroplast stroma. maintains, so CA has a noticeable effect on catalyzing CO2 conversion [31]. In addition, the activity of rubisco, the pH of chloroplast stroma, etc., can also affect the CO2 conversion efficiency [34]. The favored form of stacking Ci is HCO3 that is approximately 1000-fold less permeable to lipid membranes than the uncharged CO2 molecules. The CO2 absorption system can recycle or recapture leaking CO2 in order to efficiently fix the CO2 and prevent its escape from the cell [35].

3. Environmental Conditions for the Growth of the Microalgae

The effect of diverse environmental conditions on the growth rate of microalgae is depicted in Figure 4. The optimal range of conditions to achieve high CO2 fixation rates and the growth efficiency also vary by microalgae species. The effects of microalgae growth conditions on carbon sequestration efficiency and biomass production are summarized below.

3.1. Light

Light is the basic energy source affecting the photosynthesis dynamics of microalgae, which can affect cell growth and metabolism by controlling the light source, light intensity, interval, area, etc. [36]. Excessive light intensity may lead to photooxidation and photoinhibition, while low light levels would limit growth [37]. The majority view is that photoinhibition is the primary factor reducing algal output. Until light saturation is attained, the microalgae growth rate increases linearly with increasing light intensity at low light levels. The optimal light intensity for microalgae growth is usually 26–400 µmol photons m−2 s−1 [38]. Lipid synthesis of tetradesmus obliquus reached the maximum at 200 µmol m−2 s−1, accounting for 45.31% of the dry biomass, which would decrease provided that further augmented the light intensity [39]. Additionally, according to Kim et al., microalgae production rates of Scenedesmus sp. was about 45% higher than at a single wavelength at 400–700 nm white light [40]. By controlling the light wavelength, photosynthesis, gene transcription, enzyme activation and cellular composition can be impacted to the point that the biomass and lipid content of microalgae are altered [41].

3.2. Temperature

Temperature is a major factor regulating the cellular, morphological, and physiological responses of microalgae, now that it impacts their photosynthesis, which leads to changes in the carbon sequestration efficiency of microalgae. Zhao et al. revealed that the most suitable temperature for the growth of the most common microalgae was between 15 and 26 °C [42]. Overall, with decreasing temperature within the appropriate range, rubisco activity reduces, the index of unsaturated fatty acid augments, the growth rate reduces, biomass is reduced, and carbon fixation efficiency also reduces significantly. Nevertheless, high temperatures frequently have irreversible damage on microalgae. Sachdeva et al. discovered that Chlorella pyrenoidosa M18 were able to survive at temperatures up to 47 °C, with the highest average growth rate at 37 °C. At high temperature or direct sun, this algal species had a higher lipid yield of 44.51%, compared to room temperature [43]. As shown in Table 1, the optimal growth temperature of microalgae varies by species, and is also influenced by other environmental parameters (e.g., light intensity and CO2 concentration) [44].

3.3. pH

By altering the activity of the cellular metabolic enzymes and the uptake and usage of ions by microalgae cells, the pH value influences the physiological metabolism of microalgae. The energy costs of HCO3 transfer to cytosol are decreased at pH ranges between 7.5 and 8.5, which lowers the cost of carbon fixation [49]. The depletion of Ci by microalgae cells growth leads to an increase in pH, which might alter the biochemical reaction properties of microalgae, in turn with promoting cell rupture. Changes in pH can affect CA activity, leading to affect microalgae growth. Buffers such as sodium hydroxide or calcium carbonate to adjust pH to the best level adapted to microalgae growth can further boost the fixation rate of CO2 and biomass production [50].
Most microalgae are suitable for cultivation under neutral pH conditions [50], with exceptions, such as Chlorococcum could live in pH 4.0, and Spirulina at pH 11.0 [51]. Razzak et al. discovered that Nannochloropsis oculata grew well between medium pH 5.5 and 6.5 [51]. Graesiella sp. WBG-1 had the highest CO2 fixation rate and lipid content at pH 8.0–9.0, which were 0.26 g/L/d and 46.28%, respectively. Although the usage rate of CO2 increased along with the pH, the optimum pH for microalgae development did not have the highest utilization rate of CO2 [52]. Therefore, it is essential to cultivate algae species that can grow well under high pH values in order to effectively utilize the carbon sequestration capacity of microalgae.

3.4. Nutrient Element

The building blocks of microalgae’s cell synthesis include carbon, nitrogen, and phosphorus, which are also crucial nutrients for the biomass growth. To some extent, the photosynthesis of microalgae is influenced by the species, morphology, and quality of the nutrients. Carbon–nitrogen ratio (C/N) is among the important factors affecting carbon fixation efficiency, biomass accumulation and productivity of value-added components. Spirulina platensis had been nuclear radiated and cultured in specific cultures. When the ratio of NH4HCO3 and NaNO3 was set at 1:4, carbon utilization efficiency of the hybrid process could reach 40.45%, But the excessively high concentration of NH4HCO3 will also generate toxicity for microalgae, which results in a lower biological yield [53]. Appropriately increasing the concentration of phosphorus is beneficial to microalgae development and lipid accumulation because some microalgae may utilize it to manufacture organic esters [54,55]. Microalgae cause phosphorus to convert ADP into ATP through phosphorylation, which can also precipitate phosphate through cell adsorption or regulating pH as shown in Figure 5. Because wastewater contains the above elements, growing microalgae can remove pollutants while fixing carbon, but this also faces some challenges, as detailed in a later article [30].

3.5. Carbon Dioxide Concentration

The capability of different microalgae to tolerate CO2 is different. Even though certain microalgae have great CO2 tolerance and can grow across most of the CO2 concentration range, the optimal growth concentration is determined. The statistics are shown in Table 2 below. Some microalgae can grow normally at low concentrations of CO2, while some will only show high growth rates at high concentrations of CO2. Either a too high or too low CO2 concentration reduces the CO2 fixation efficiency and the biomass yield. To some degree, increasing the CO2 concentration can enhance the carboxylation activity of the rubisco, suppress its oxidative activity, and accelerate photosynthesis [56]. However, too high a CO2 concentration will lower pH, which will reduce the activity of CA and impede cell growth [57].
The maximum biomass output and the CO2 fixation rate of chlorella vulgaris both increased by 57% and 56%, respectively, as the CO2 content increased from 3% to 7% [71]. Rodas-Zuluaga et al. indicated that when growing microalgal strains at 0.03% to 20% CO2, Botryococcus braunii grew well at CO2 of 0.03%, while Scenedesmus sp. had the highest biomass yield at 20% CO2 [61]. These findings all point to the influence of microalgal species on the growth and CO2 tolerance of microalgae.

4. Strategies for Improving Photosynthetic Efficiency in Microalgae

Selection of microalgae strains with a fast growth rate, strong environmental adaptability, and high CO2 fixation ability is the most important step to improve the effect of CO2 fixation in microalgae. In addition to selecting microalgae with excellent traits from natural strains, random mutagenesis, ALE, and genetic engineering that enhancing the specific metabolic phenotype of microalgae and improving their environmental adaptability are also commonly used strategies, as shown in Figure 6. Moreover, the maximum productivity of target compounds and conditions for rapid growth of microalgae are often mutually exclusive, and algal productivity can be further enhanced by means such as mutagenesis and/or genetic engineering [72]. The effects of these methods on improving the growth performance of microalgae are shown in Table 3.

4.1. Random Mutagenesis

Random mutagenesis with simplicity of operator, high reliability, and non-orientation can be applied to culture mutants with the optimal features of a high carbon fixation efficiency, a high lipid yield, and tolerated CO2 [80]. Random mutagenesis applied to any microalgae strain can be divided into two categories—chemical mutagenesis and physical mutagenesis, using physical or chemical means to influence the strain—resulting in random alterations in the genome. Its advantage is that this technology can mutate and ameliorate various microalgae traits without requiring comprehending the complex knowledge of physiology or genetics, and the mutants produced are not genetically modified organisms [72,81].

4.1.1. Chemical Mutagenesis

Chemical mutagenesis is for the most part used as mutagens by ethyl methane sulfonate (EMS), 1-methyl-3-nitro-1-nitrosoguanidine (MNNG), N-methyl-N-nitrosourea (MNU), N-methyl-N′-nitro-N-nitrosoguanidine (NTG), 5-bromouracil (5′-UB), etc. [82]. The advantage of chemical mutagenesis is that it does not need special equipment, can produce a high frequency of point mutations, create relatively few chromosomal aberrations, but most of the mutagens are toxic or carcinogenic, easily pollute the environment [80]. Tanadul et al. showed that the strain E200-30-40, after EMS mutagenesis, produced 59% and 53% higher lipid content and productivity than the wild-type strain, respectively, which increased biomass and lipid accumulation [74]. Nojima et al. dispersed the cells of water surface-floating microalgae strains (Botryosphaerella sp. AVFF007 and Chlorococcum sp. FFG039) treated with EMS or MNNG mutagen to obtain mutant FFG039 PM, with a biomass and lipid productivity of 1.7- and 1.9-fold greater than the wild-type strains in the absence of inhibiting biofilm formation and floating capacity [73]. The total production of carotenoids and astaxanthin in the mutant G1-C1 of Coelastrum sp. after selection by EMS and glyphosate was approximately double that of the wild type [81]. As can be seen, chemical mutagenesis is utilized frequently due to simplicity of operation and potent mutagenicity.

4.1.2. Physical Mutagenesis

Physical mutagenesis mainly includes ultraviolet (UV) mutagenesis, γ -ray mutagenesis, and ion mutagenesis. UV mutagenesis is the most common because its control is flexible, economical, fast, and effective. Compared with chemical mutagens, it does not lead to poisoning of operators and has no secondary contamination [80]. During operation, some precautions also need to be taken to reduce the risk of UV radiation to the experimenter. The mutation effect depends on microalgae characteristics and experimental conditions, and is not applicable to all species [83]. Moha-León et al. found that using UV radiation and the herbicide quizalofop-p-ethyl to select freshwater microalgae, the chosen strains had more fatty acids and fat in them [84]. The screened mutant lipid production soared by 33% using UV irradiation of Desmodesmus armatus and Chlorella vulgaris [76]. γ-rays have more deep penetration than UV, which can penetrate cells to enhance the expression of photosynthesis enzymes (e.g., rubisco), rearrange chromosomes, screen oxygen radicals, and ultimately alter genetic traits [75]. The biomass of the γ-rays domesticated mutant Chlorella PY-ZU1 was increased 2.3-fold relative to the original strain [85]. Numerous studies have proved that physical mutagenesis changes the physiological and biochemical characteristics that are typical of cells. As a result, new strains with much higher lipid enrichment capacities can be chosen.

4.2. Adaptive Laboratory Evolution

ALE is a strain improvement method based on random mutation and natural selection that can be used as a tool to study evolution, which improves the phenotype, performance, and stability of microalgae, divided into intermittent and continuous culture patterns [86,87]. Additionally, it compensates for the neglect of molecular genetic mechanisms in Darwinian evolution and its development, using high-throughput DNA sequencing as a tool to effectively model the evolutionary process of selection [88]. The efficiency of ALE rests with the original strain, the initial cell density of the microalgae, and the strategy of stress [89]. Nutritional stress and environmental stress are the two types of stress. Nutritional pressure is often used to improve the completion rate of some low-cost substrates, and environmental pressure mainly includes temperature, oxidation, and organic solvent tolerance [90]. Choosing the appropriate pressure can effectively improve the efficiency of ALE to a certain extent. Under laboratory control conditions, ALE cultures of microorganisms reach certain targets and subculture until the metabolic phenotype is stable and the evolved microalgae strains containing beneficial mutations are obtained.
In the ALE of microalgae, a single stress is typically used to better appreciate the process of tolerance [89]. Using reasonable ALE can not only improve the tolerance of microalgae to abiotic stress, but also optimize the yield of target metabolites and enhance the utilization of pollutants [86]. Controlling light factors by ALE could increase the microalgae growth rate and the accumulation of β-carotene and lutein. Thus, light stress can accelerate the removal of nitrogen and phosphate velocities in wastewater treatment [88]. At 10% and 20% CO2, Chlorella sp. strains AE10 and AE20 were obtained by ALE, and had higher CO2 tolerance than Chlorella sp. [70]. According to Table A1, ALE is a feasible strain enhancement tactic that can take advantage of microalgae’s biotechnological potential to boost the ability of carbon fixation, lipid production, and the biomass concentration for distinct strains.

4.3. Genetic Engineering

Genetic engineering focuses on the gene expression and transcription, altering the target genome by using recombinant DNA at the molecular level. In principle, there are three pathways: (1) to provide the necessary phenotype, add heterologous genes; (2) to stop gene expression through gene disruption or gene deletion, or lower the level of existing genes’ expression through RNA interference; (3) to enhance and induce expression under non-native promoters. Despite the complexity of the process, it is beneficial to boost photosynthesis, increase microalgal biomass, and increase CO2 absorption rates [72]. The biomass productivity of Nannochloropsis oceanica can be elevated by overexpression of a nuclear-encoded. At air CO2 concentrations, the mutant growth rate increased by 32% and biomass accumulation increased by 46% [78]. Genetic engineering can decrease the uncontrollability and blindness of microalgae mutagenesis, but not all species of microalgae are suitable for genetic engineering, and the resulting transgenic organisms are still seen as potential risks to the environment and human health. The foremost limitations of genetic engineering are that it is time-consuming, costly, and requires complex equipment and experimental conditions.

5. Application of Carbon Dioxide Fixation Technology in Microalgae

5.1. In the Atmosphere

As mentioned above, microalgae cultures are considered a promising strategy to capture CO2 from the atmosphere due to their high growth rate and CO2 fixation capacity. In December 2022, the CO2 levels in the atmosphere reached 418 ppm [91]. Microalgae use CCM to increase the CO2 concentration near rubisco in order to achieve carbon fixation [92]. Tsai et al. proved that the symbiosis of microalgae with a natural medium has maximum CO2 consumption efficiency and favorable CO2 fixation ability [93]. Microalgae are typically cultivated in enclosed systems or open ponds, where they can absorb CO2 from the air to supply the cell growth and eventually produce lipids, carbohydrates, and proteins [94,95]. Open ponds are often used in large-scale industrial growth systems to grow microalgae because they are cost-effective and have a higher production capacity compared to closed systems (i.e., photobioreactor). However, disadvantages include the large area, unstable culture conditions, easy pollution, and that they are limited by too few microalgae strains. A photobioreactor can achieve aseptic operation, have a relatively stable culture conditions, and prevent the evaporation of water, but its construction and operation costs are higher. Although direct air capture requires no equipment and energy, the effectiveness of carbon sequestration is relatively low and is affected by environmental factors [30,96,97]. Therefore, the common microalgae culture systems are generally open ponds and photobioreactors.

5.2. Flue Gas

Flue gas is a cheap and abundant source of CO2, coal flue gas contains a 12–15 volume percentage (vol%) of CO2, while natural gas contains a 4–8 volume percentage (vol%) of CO2 [98,99]. The composition of flue gas is more complex, and will depend on the type of combustion raw materials, generally containing a large proportion of N2 and CO2, a little bit of H2O and O2, and a minor amount of nitrogen and sulfur oxides, heavy metals, dust, and other contaminants. The use of microalgae to reduce CO2 emissions in flue gas is very promising, but the high concentration of some pollutants (e.g., SOX and NOX) may have severe toxic effects on microalgae cells and inhibit the growth of microalgae, as well as inhibit the ability of microalgae to sequester carbon, as shown in Figure 7 [100]. Among the four flue gas microalgae remediation strategies of microalgae, the use of microalgae to directly mitigate the flue gas pollution method has higher economic and environmental benefits because it does not use any adsorbent and can use cultured microalgae to produce secondary products [92]. The associated expenses, pollutant emissions, and energy requirements are lowered since the CO2 concentration for algae development is comparable to the average flue gas CO2 concentration [101]. Therefore, strain screening that can tolerate a high CO2 content and high temperature resistance is the premise of realizing CO2 fixation in flue gas.
The reduced growth rate at high CO2 concentrations is often associated with acidification, leading to inactivation of key enzymes in the C3 cycle, and homeostatic reactions enable CO2-resistant strains to adjust their pH [102]. Yen et al. showed that Chlorella sp. achieved the maximum growth rate at a 10% CO2 concentration, which shows a high CO2 tolerance [103]. Chlorella fusca LEB 111 exhibited the largest daily bio-fixation amount of CO2 in flue gas [104]. Microalgae cells can capture low levels of nitrogen oxides as sources of nitrogen. Further, there are polysaccharides, proteins, and lipids on the surface of the cell wall of microalgae, which contain charged functional groups that can attract and combine with heavy metals. Consequently, microalgae can be employed as adsorbents to effectively remove heavy metals [103].
In conclusion, the use of microalgae to capture CO2 from flue gas, while removing the nitrogen oxides, sulfur oxides, and heavy metals in flue gas is an efficient way to reduce CO2 emissions and air pollution. Accordingly, obtaining sufficient carbon sources contributes to the accumulation of biomass lipids and the increase in biological production, which can be applied to raw materials for biofuels or biorefinery. This approach maximizes economic profit, ensures the sustainable and ecological benign production of biomass, and is consistent with the development requirements of decreasing CO2 emissions, which mitigates the effect of human activity on the climate. For now, most of the research on flue gas still has attached importance to laboratory research under controlled conditions, so further research and optimization are essential.

5.3. In Wastewater

The increasing urbanization and growth of the world’s population have resulted in a steep rise in water consumption, making wastewater treatment among the greatest difficulties in the world. Microalgae wastewater treatment systems have a substantial economic value compared to conventional wastewater treatment technologies, which rely on expensive energy and chemicals and increase greenhouse gas emissions [105]. Wastewater contains most of the nutrients needed for microalgae growth and the trace metals necessary for photosynthesis, such as ammonias, phosphates, irons, coppers, and zincs. The combination of wastewater purification, CO2 capture, and microalgae cultivation can reduce the cost of sewage treatment, lower the use of chemicals in the processing process, and slow down the emission of CO2. Additionally, the resulting biomass can be further processed to produce biofuels, which alleviates the current energy crisis [98,106].
The efficiency of wastewater treatment by microalgae is relevant to wastewater type, nutritional characteristics, photobioreactor types, and culture methods [25]. The tolerance of organic pollutants in wastewater also varies among various species, as shown in Table A2. The content of nitrogen and phosphorus in domestic wastewater is low, the concentration of toxic and harmful substances in agricultural wastewater is low, and industrial wastewater usually contains a large amount of oil, heavy metals, and toxic pollutants. Song et al. showed that Chlorella sp. was cultivated in a system mixed with soybean wastewater and bicarbonate solution (NH4HCO3). At pH = 7, the low-NH4HCO3 concentration system had the highest biomass yield (0.74 g/L) and the highest carbon bioconversion efficiency [107]. Scenedesmus dimorphus was cultured in tertiary urban sewage with different NP ratios, and when the NP ratio was 8:1 at 4% CO2, the maximum biological fixation rate of microalgae reached 49.6 mg/L/d [108]. Hu et al. proved that Chlorella sp. L166 realized the efficiency of a maximum removal of TN, TP, COD, and CO2 with an NP ratio of 5:1 in 20% soybean wastewater, introducing 5% CO2 at a rate of 0.1 vvm [109].
Combining the capture of CO2 from flue gas with wastewater treatment using microalgae culture to produce biofuels is a sustainable and economical wastewater treatment technology [110]. The extraction of high-value-added products in microalgae will also immensely encourage its large-scale industrialization that has a wide range of application potential.

5.4. Other Applications

Microalgae contain high-value fatty acids, pigments, and vitamins, etc. After special treatment, microalgae biomass can also be converted into biodiesel, methane, and other energy sources. Microalgae with a high oil content have the potential to produce 25-fold higher oil yields than conventional biodiesel crops such as the oil palm [111]. Astaxanthin extracted from Haematococcus pluvialis is often used in cosmetics as to its strong antioxidant capacity. In addition, eating astaxanthin is thought to prevent or control different diseases, and it is commonly used as a red pigment in food [112]. Polyunsaturated fatty acid has conducive effects on fetal development, preventing cardiovascular disease, and even improving cognitive function in Alzheimer’s disease patients, which is used as nutritional supplements [113]. In conclusion, microalgae biomass can be applied in food, bio-medicine, cosmetics, energy, and other industries, with a high potential application value.

6. A Future Prospect for Microalgae Carbon Dioxide Fixation Technology

6.1. Selection of Seeds Rationally

Different microalgae have different carbon fixation effects, so microalgae species that have a fast growth rate, strong environmental adaptability, high photosynthetic efficiency, a high biological yield, and are easy to cultivate outdoors on a large scale can be selected in order to improve the photosynthesis efficiency of microalgae [114]. In the process of industrial application, due to the differences in actual conditions, natural strains sometimes cannot meet the production requirements. The measures of random mutagenesis, ALE, and genetic engineering are adopted to obtain more evolved microalgae strains that it has stable metabolic phenotype to improve the cumulative effect of target products [114,115]. However, random mutagenesis produces unpredictable effects, with large cost of investment and a potential for cancer in the environment and in humans. The ALE mechanism requires further exploring, and the characteristics of evolution are difficult to define. Genetic engineering is time-consuming, expensive, and limited by a deep understanding of the genetic mechanisms of microalgae [115,116]. Therefore, how to sift the appropriate species of microalgae and ameliorate it in order to obtain the commercial application of microalgae species need to be researched.

6.2. To Optimize the Culture Conditions of Microalgae

The differences in culture conditions (such as light, temperature, pH, nutrient elements, and CO2 concentration) will change the production and CO2 fixation efficiency of microalgae [117]. The viability of CO2 fixation applications in microalgae is dominated by photosynthetic productivity and the biomass output of microalgae. During the growth of microalgae, carbon fixation efficiency is maximized by strictly controlling the growth conditions.

6.3. To Construct of Microalgae Carbon Dioxide Fixation Technology as the Core of the Industrial Model

By combining microalgae CO2 fixation technology with wastewater treatment and flue gas treatment, a green and low-carbon recycling industry model with microalgae as the core is formed. Microalgae cultivation provides an effective, environmentally friendly, and continuable solution for wastewater and flue gas treatment [95,118]. This scheme controls the emission of CO2, fosters the recycling of nutrients in wastewater (e.g., nitrogen and phosphorus), absorbs pollutants in wastewater and flue gas, reduces the cost of CO2 fixation, produces high-value-added products, and achieves win–win environmental and economic benefits [119,120]. However, most of the studies in the existing literature are conducted in laboratory conditions, and the follow-up studies should give priority to large-scale application to reasonably evaluate their industrial feasibility.

6.4. Comprehensive Development and Utilization of High-Value-Added Products of Microalgae

Microalgae biomass can be used extensively in a wide range of industries, which is crucial for alleviating the energy crisis, reducing environmental contamination, and promoting food security [115,121,122]. Improving the productivity of related products (such as lipids, pigments, and nutrients) is available for improving the economic benefits of microalgae CO2 fixation technology [123,124], which contributes to impelling industrialization development of CO2 fixation technology.

6.5. Potential for Carbon Fixation in the Microalgae

In addition to carbon sequestration in microalgae, there are some commonly used methods of carbon capture. Table 4 summarizes the advantages and limitations of various methods. Hence, microalgae CO2 fixation technology has a wide range of application prospects as a new carbon capture technology. In the industrial field, it can be applied in the waste gas treatment of coal, chemical industry, and other industries, to convert CO2 into useful microalgae biomass via photosynthesis [102]. Similarly, microalgae carbon sequestration technology can also be combined with wastewater treatment to purify water quality by absorbing nitrogen, phosphorus, and other nutrients in wastewater, which can be used in agriculture, industry, and other fields [125]. In the field of energy, biomass generated by microalgae CO2 fixation technology can be used to produce biofuels, which can replace traditional petroleum energy and reduce dependence on fossil fuels, thus reducing CO2 emissions. Microalgae biomass can also be used as a source of raw materials for medicines, cosmetics, food, and other fields [126]. There is still a long way to go to apply the achievements of carbon fixation technology from lab-scale research to large-scale application. For example, industrial carbon sequestration technology of microalgae is still faced with the problems such as low carbon sequestration efficiency, and further reduction in production costs. With the continuous progress of technology, the application scope of microalgae CO2 fixation technology will continue to expand, the cost will continue to reduce, and the production efficiency will also continue to improve. Therefore, microalgae CO2 fixation technology has great development potential and application prospects.
In short, microalgae carbon sequestration technology can reduce CO2 emissions and delay global warming while providing high-value-added products to achieve CO2 resource utilization. Therefore, compared with other carbon fixation methods, it has higher cost benefits, potential for effective carbon fixation, etc., which meets the requirements of green development and plays an important role in the realization of the goal of carbon neutrality.

7. Conclusions

Due to global warming, microalgae carbon sequestration is among the most promising and sustainable methods to fix CO2. Microalgae, with a relatively faster growth rate and higher CO2 fixation efficiency, can also be used in wastewater treatment, flue gas treatment, biofuel production, as well as high-value-added products manufacture (e.g., proteins and lipids), which can maximize the economic benefits. Hence, it is an ideal material for biological capture of CO2 under the background of “dual-carbon”. Nevertheless, the future application of microalgae is still facing quite a few challenges. At present, many kinds of microalgae have been used for laboratory-scale testing. Limited by the technical level and production cost, the large-scale industrial biological sequestration of microalgae is still in its infancy, and no pilot-scale studies have yet been conducted.
To accelerate the realization of the carbon sequestration scale of microalgae, we should start by studying the microalgae CO2 fixation mechanism, combine the CO2 fixation technology of microalgae with high-value-added biomass production, promote the industrialization of microalgae CO2 fixation technology, and establish and optimize a better mechanism, to achieve the purpose of promoting the circular economy and sustainable development. Based on this, carbon sequestration technology of microalgae needs to be innovated and improved according to the following aspects: (1) using relevant technologies to select suitable strains, (2) making the microalgae growing process more ecologically friendly by utilizing flue gas and wastewater treatment technology, and (3) to make full use of high-value-added products to achieve the greatest economic benefits. It is believed that the economically feasible and environmentally friendly industrialization model with microalgae CO2 fixation technology as the core will be promoted and widely used in the foreseeable future.

Author Contributions

Conceptualization, G.L. and W.X.; methodology, G.L.; software, W.X.; validation, T.Y., W.X. and G.L.; formal analysis, T.Y.; investigation, W.X.; resources, G.L.; data curation, W.X.; writing—original draft preparation, W.X.; writing—review and editing, T.L.; visualization, W.X.; supervision, T.L.; project administration, T.L.; funding acquisition, G.L. All authors have read and agreed to the published version of the manuscript.


This research was funded by the National Natural Science Foundation of China (Grant NO. 32172277).

Data Availability Statement

The data presented in this study are available on request from the corresponding author.


We wish to thank the National Natural Science Foundation of China (32172277) and the Beijing Technology and Business University for their support.

Conflicts of Interest

The authors declare no conflict of interest.

Appendix A

Table A1. Characteristics of the modified microalgal strains by ALE.
Table A1. Characteristics of the modified microalgal strains by ALE.
Initial StrainsMediumInitial Cell DensityCyclesStressesOutcomeRef.
Chlorella sp.BG11OD750 of 0.131 cycles (97 days)10% CO2The maximal biomass concentration of AE10 was 3.68 ± 0.08 g/L in 30% CO2, which was 2.94 fold compared to the original strain.[70]
Chlamydomonas reinhardtiiTAP and TAP-NOD680 of 0.128 cycles (84 days)Nitrogen starvationALE combined with nitrogen starvation substantially increased total lipid production, particularly for low-starch mutants. The endpoint strain of cc4334 under nitrogen starvation stress had the highest lipid productivity.[129]
Schizochytrium sp. HX-308Main culture medium contained 40 g/L glucose and 0.4 g/L yeast extract-40 cycles (40 days)High oxygenThe adapted strain generated higher cell dry weight and lower lipid accumulation.[90,130]
Schizochytrium sp. HX-308Medium with 30 g/L NaCl at a concentration of 1% v/v-150 daysHigh salinityThe ALE150 showed a maximal cell dry weight of 134.5 g/L and a lipid yield of 80.14 g/L, representing a 32.7 and 53.31 increase over the starting strain, respectively.[131]
Chlorella sp. L5TAP medium with 500 mg/L phenol0.6 g/L31 cycles (95 days)High concentration phenolThe upregulations of the genes according to antioxidant enzymes and carotenoids synthesis were tolerated high phenol.[132]
Chlorella sp.TAP medium0.6 g/L31 cycles (95 days)High concentration phenolThe strain had higher phenol biodegradation rates.[133]
Phaeodactylum tricornutum (CCMP-2561)Artificial seawater added with f/2 medium without silica1 × 106 cells/mL35 cycles (nearly 252 days)Reducing salinity70% salinity potentiated the algae to enhance PUFAs.[134]
Picochlorum sp. BPE23Liquid growth mediumOD750 of 0.2322 daysSupra-optimal temperatureAt the optimal growth temperature of 38 °C, the biomass
yield on light was 22.3% higher, and the maximal growth rate was 70.5% higher than the wild type.
Synechocystis sp. PCC 6803BG11 medium supplemented with 1.5% agarOD730 of 0.243 cycles (303 days)3% NaClAll ALE-generated strains except S3 and S7 had a significantly higher growth rate than the control strain[136]
K. marxianusYPD mediumOD600 of 0.865 daysVarious temperatureThe adapted K. marxianus strain accumulates glycerol and trehalose in response to lactose stress and ameliorate osmotolerance in K. marxianus cells.[137]
Scenedesmus sp. SPPModified Chu13 medium-10 daysSalinity stress, light stress, temperature stressThe triple stress-adapted strain showed the highest lipid content.[138]
Schizochytrium sp. CCTCC M209059Main culture medium contained 40 g/L glucose and 0.4 g/L yeast extract-80 daysHigh temperatureThe adaptive strain showed a higher growth rate and lower temperature sensitivity.[130,139]
Nannochloroposis oculata CCMP525The f/2 agar medium0.32 g/L24 cyclesHigh temperatureIn a 2-L photobioreactor at 35 °C, biomass and lipid productivity were 1.43-fold and 2.24-fold higher, respectively, than wild type at 25 °C.[140]
Crypthecodinium cohnii ATCC 30556Regular fermentation medium (27 g/L glucose, 25 g/L sea salt, and 6 g/L yeast extract)OD490 of 0.1280 cycles (840 days)Varying contents of the fermentation (30–90%) supernatantThe cell growth and DHA productivity of the evolved strain (FS280) were increased by 161.87 and 311.23%.[77]
Chlorella sp. AE10BG11 medium0.04 g/L46 cycles (138 days)High salinityChlorella sp. S30, has the potential for CO2 capture under 30 g/L salt and 10% CO2 conditions.[141]
Dunaliella salina CCAP 19/18The f/2 medium1 × 105 cells/ml5 cycles (25 days)Blue LEDThe beta-carotene concentration (33.94 ± 0.52 μM) was enhanced by 19.7% compared to that observed for the non-ALE-treated wild type of D. salina under the B-R system (28.34 ± 0.24 μM).[142]
Table A2. Comparison of the removal efficiency of pollutants in different wastewater types by various microalgae.
Table A2. Comparison of the removal efficiency of pollutants in different wastewater types by various microalgae.
Waste StreamWastewater SourceSpeciesReactorLight IntensityAmbient Temperature (°C)Sampling Time (day)Water Quality Index (mg/L)Nutrient Removal Efficiency (%)Maximum Biomass Concentration (g/L)CO2 Bio-Fixation (mg/L/d)Lipid Productivity (mg/L/d)Ref.
Agricultural wastewaterSoybean processing wastewaterChlorella sp. L166Erlenmeyer flask6000 lux25 ± 1185320106.9923.2878.2096.0795.551.52--[109]
Starch processing wastewaterChlorella pyrenoidosaConical flask127 μmol m−2 s−125 ± 16–7702.4–1026.2240.3–382.722.7–40.265.9983.0696.971.90-30.15[143]
Swine wastewaterMBFJNU-1Flask--12824.53547.7881.72-90.5191.540.63--[144]
Agricultural wastewater and municipal wastewaterSwine wastewater 2:2 secondary treated municipal wastewaterChlorella sorokinianaErlenmeyer flask126 μmol m−2 s−128 ± 210-337.3230.88-63.9093.021.31-23[145]
Swine wastewater 1:3 secondary treated municipal wastewaterDesmodesmus communisErlenmeyer flask126 μmol m−2 s−128 ± 210-188.6115.77-88.0299.731.02--
Municipal wastewaterWastewater influent after primary settling tankChlorella sorokiniana pa.91Erlenmeyer flask4000 lux3016211.42.01
The primary sedimentation tankChlorella vulgaris ATCC 13482Cylindrical glass bottles90 ± 5 μmol m−2 s−1251029346.6719.50-93.4094.100.94140.91-[147]
Scenedesmus obliquus FACHB 417Cylindrical glass bottles90 ± 5 μmol m−2 s−1251029346.6719.50-91.5091.300.87129.82-
Effluent of anaerobically digested food wastewaterScenedesmus bijugaErlenmeyer flask80 μmol m−2 s−130285923237047.80-86.6090.501.49-15.59[148]
The sewage from the sewerTetradesmus obliquus PF3Conical flask6000 lux25 ± 15267434.99093.20991.8551-[149]
Sterilized sewageTetradesmus obliquus PF3Conical flask6000 lux25 ± 15210404.704294.70991.8558-
Targeting the tertiary treatment of wastewaterNeochloris oleoabundansErlenmeyer flask60 μmol·m−2 s−12514-4218.50-10031.301.17145-[150]
Domestic wastewater from secondary settling tanksScenedesmus obliquusConical flask14,500 lux23 ± 21072.1612.441.08-98.9097.60---[151]
Manure wastewaterScenedesmus dimorphus (FACHB-496)Erlenmeyer flask60–80 μmol·m−2 s−126 ± 27-306.15115.08-88.1673.98-638.13-[152]
Industrial wastewaterArtificial brewery wastewaterScenedesmus sp. 336Erlenmeyer flask6000 lux25 ± 110210045773.6675.9695.71--38[153]
Chlorella sp. UTEX1602Erlenmeyer flask6000 lux25 ± 110210045744.9781.4397.54---
Palm oil mill effluent from an anaerobic treatment pondChlorella sp. (UKM2)Transparent glass bottle266 μmol m−2 s−125 ± 2152900330--80.90--120.80-[154]
Waste molassesScenedesmus sp. Z-4Erlenmeyer flask3000 lux107514,0004586787.290.5088.602.5-78[155]
Membrane-treated distillery wastewaterChlorella vulgarisErlenmeyer flask2000 lux259---72.2480940.65--[156]
Textile wastewaterMixed microalgae (Chlorella Species and Scenedesmus sp.)Conical flask212.77 mol m−2 s−1-131900480.503178.7893.301000.4--[157]
The simulated brewery effluentScenedesmus obliquusErlenmeyer flask12,000 lux30 ± 39363554-57.520.80-0.9--[158]
* COD: chemical oxygen demand; TN: total nitrogen; TP: total phosphorus.


  1. Li, S.; Li, X.; Ho, S.H. How to Enhance Carbon Capture by Evolution of Microalgal Photosynthesis? Sep. Purif. Technol. 2022, 291, 120951. [Google Scholar] [CrossRef]
  2. Yang, S.; Yang, D.; Shi, W.; Deng, C.; Chen, C.; Feng, S. Global Evaluation of Carbon Neutrality and Peak Carbon Dioxide Emissions: Current Challenges and Future Outlook. Environ. Sci. Pollut. Res. 2022, 43, 101371. [Google Scholar] [CrossRef]
  3. Li, G.; Hu, R.; Hao, Y.; Yang, T.; Li, L.; Luo, Z.; Xie, L.; Zhao, N.; Liu, C.; Sun, C.; et al. CO2 and Air Pollutant Emissions from Bio-coal Briquettes. Environ. Technol. Inno. 2023, 29, 102975. [Google Scholar] [CrossRef]
  4. Malhi, G.S.; Kaur, M.; Kaushik, P. Impact of Climate Change on Agriculture and Its Mitigation Strategies: A Review. Sustainability 2021, 13, 1318. [Google Scholar] [CrossRef]
  5. Liu, Y.; Li, N.; Zhang, Z.; Huang, C.; Chen, X.; Wang, F. The Central Trend in Crop Yields under Climate Change in China: A Systematic Review. Sci. Total Environ. 2020, 704, 135355. [Google Scholar] [CrossRef] [PubMed]
  6. Krūmiņš, J.; Kļaviņš, M.; Ozola-Davidāne, R.; Ansone-Bērtiņa, L. The Prospects of Clay Minerals from the Baltic States for Industrial-Scale Carbon Capture: A Review. Minerals 2022, 12, 349. [Google Scholar] [CrossRef]
  7. Kamyab, H.; Din, M.F.M.; Hosseini, S.E.; Ghoshal, S.K.; Ashokkumar, V.; Keyvanfar, A.; Shafaghat, A.; Lee, C.T.; asghar Bavafa, A.; Majid, M.Z.A. Optimum Lipid Production Using Agro-Industrial Wastewater Treated Microalgae as Biofuel Substrate. Clean. Technol. Environ. Policy 2016, 18, 2513–2523. [Google Scholar] [CrossRef]
  8. Ochedi, F.O.; Liu, D.; Yu, J.; Hussain, A.; Liu, Y. Photocatalytic, Electrocatalytic and Photoelectrocatalytic Conversion of Carbon Dioxide: A Review. Environ. Chem. Lett. 2021, 19, 941–967. [Google Scholar] [CrossRef]
  9. Smit, B. Carbon Capture and Storage: Introductory Lecture. Faraday Discuss. 2016, 192, 9–25. [Google Scholar] [CrossRef][Green Version]
  10. Rodrigues, C.F.A.; Dinis, M.A.P.; Lemos de Sousa, M.J. Review of European Energy Policies Regarding the Recent “Carbon Capture, Utilization and Storage” Technologies Scenario and the Role of Coal Seams. Environ. Earth Sci. 2015, 74, 2553–2561. [Google Scholar] [CrossRef]
  11. da Rosa, G.M.; de Morais, M.G.; Costa, J.A.V. Green Alga Cultivation with Monoethanolamine: Evaluation of CO2 Fixation and Macromolecule Production. Bioresour. Technol. 2018, 261, 206–212. [Google Scholar] [CrossRef]
  12. Detheridge, A.; Hosking, L.J.; Thomas, H.R.; Sarhosis, V.; Gwynn-Jones, D.; Scullion, J. Deep Seam and Minesoil Carbon Sequestration Potential of the South Wales Coalfield, UK. J. Environ. Manag. 2019, 248, 109325. [Google Scholar] [CrossRef] [PubMed]
  13. Salek, S.S.; Kleerebezem, R.; Jonkers, H.M.; jan Witkamp, G.; Van Loosdrecht, M.C.M. Mineral CO2 Sequestration by Environmental Biotechnological Processes. Trends Biotechnol. 2013, 31, 139–146. [Google Scholar] [CrossRef][Green Version]
  14. Yeh, J.T.; Resnik, K.P.; Rygle, K.; Pennline, H.W. Semi-Batch Absorption and Regeneration Studies for CO2 Capture by Aqueous Ammonia. Fuel Process. Technol. 2005, 86, 1533–1546. [Google Scholar] [CrossRef]
  15. Rossi, F.; Olguín, E.J.; Diels, L.; De Philippis, R. Microbial Fixation of CO2 in Water Bodies and in Drylands to Combat Climate Change, Soil Loss and Desertification. N. Biotechnol. 2015, 32, 109–120. [Google Scholar] [CrossRef]
  16. Yahya, L.; Harun, R.; Abdullah, L.C. Screening of Native Microalgae Species for Carbon Fixation at the Vicinity of Malaysian Coal-Fired Power Plant. Sci. Rep. 2020, 10, 22355. [Google Scholar] [CrossRef]
  17. Dasan, Y.K.; Lam, M.K.; Yusup, S.; Lim, J.W.; Show, P.L.; Tan, I.S.; Lee, K.T. Cultivation of Chlorella Vulgaris Using Sequential-Flow Bubble Column Photobioreactor: A Stress-Inducing Strategy for Lipid Accumulation and Carbon Dioxide Fixation. J. CO2 Util. 2020, 41, 101226. [Google Scholar] [CrossRef]
  18. Premaratne, M.; Liyanaarachchi, V.C.; Nishshanka, G.K.S.H.; Nimarshana, P.H.V.; Ariyadasa, T.U. Nitrogen-Limited Cultivation of Locally Isolated Desmodesmus sp. For Sequestration of CO2 from Simulated Cement Flue Gas and Generation of Feedstock for Biofuel Production. J. Environ. Chem. Eng. 2021, 9, 105765. [Google Scholar] [CrossRef]
  19. Ding, G.T.; Mohd Yasin, N.H.; Takriff, M.S.; Kamarudin, K.F.; Salihon, J.; Yaakob, Z.; Mohd Hakimi, N.I.N. Phycoremediation of Palm Oil Mill Effluent (POME) and CO2 Fixation by Locally Isolated Microalgae: Chlorella Sorokiniana UKM2, Coelastrella sp. UKM4 and Chlorella Pyrenoidosa UKM7. J. Water Process Eng. 2020, 35, 101202. [Google Scholar] [CrossRef]
  20. Li, G.; Hao, Y.; Yang, T.; Xiao, W.; Pan, M.; Huo, S.; Lyu, T. Enhancing Bioenergy Production from the Raw and Defatted Microalgal Biomass Using Wastewater as the Cultivation Medium. Bioengineering 2022, 9, 637. [Google Scholar] [CrossRef] [PubMed]
  21. Lam, M.K.; Lee, K.T.; Mohamed, A.R. Current Status and Challenges on Microalgae-Based Carbon Capture. Int. J. Greenh. Gas Control 2012, 10, 456–469. [Google Scholar] [CrossRef]
  22. Singh, S.P.; Singh, P. Effect of CO2 Concentration on Algal Growth: A Review. Renew. Sustain. Energy Rev. 2014, 38, 172–179. [Google Scholar] [CrossRef]
  23. Huang, Z.; Zhang, J.; Pan, M.; Hao, Y.; Hu, R.; Xiao, W.; Li, G.; Lyu, T. Valorisation of Microalgae Residues after Lipid Extraction: Pyrolysis Characteristics for Biofuel Production. Biochem. Eng. J. 2022, 179, 108330. [Google Scholar] [CrossRef]
  24. Raeesossadati, M.J.; Ahmadzadeh, H.; McHenry, M.P.; Moheimani, N.R. CO2 Bioremediation by Microalgae in Photobioreactors: Impacts of Biomass and CO2 Concentrations, Light, and Temperature. Algal Res. 2014, 6, 78–85. [Google Scholar] [CrossRef]
  25. You, X.; Yang, L.; Zhou, X.; Zhang, Y. Sustainability and Carbon Neutrality Trends for Microalgae-Based Wastewater Treatment: A Review. Environ. Res. 2022, 209, 112860. [Google Scholar] [CrossRef]
  26. Cheah, W.Y.; Ling, T.C.; Juan, J.C.; Lee, D.J.; Chang, J.S.; Show, P.L. Biorefineries of Carbon Dioxide: From Carbon Capture and Storage (CCS) to Bioenergies Production. Bioresour. Technol. 2016, 215, 346–356. [Google Scholar] [CrossRef]
  27. Burlacot, A.; Dao, O.; Auroy, P.; Cuiné, S.; Li-Beisson, Y.; Peltier, G. Alternative Photosynthesis Pathways Drive the Algal CO2-Concentrating Mechanism. Nature 2022, 605, 366–371. [Google Scholar] [CrossRef]
  28. Singh, S.K.; Sundaram, S.; Sinha, S.; Rahman, M.A.; Kapur, S. Recent Advances in CO2 Uptake and Fixation Mechanism of Cyanobacteria and Microalgae. Crit. Rev. Environ. Sci. Technol. 2016, 46, 1297–1323. [Google Scholar] [CrossRef]
  29. Prasad, R.; Gupta, S.K.; Shabnam, N.; Oliveira, C.Y.B.; Nema, A.K.; Ansari, F.A.; Bux, F. Role of Microalgae in Global CO2 Sequestration: Physiological Mechanism, Recent Development, Challenges, and Future Prospective. Sustainability 2021, 13, 13061. [Google Scholar] [CrossRef]
  30. Zhou, W.; Wang, J.; Chen, P.; Ji, C.; Kang, Q.; Lu, B.; Li, K.; Liu, J.; Ruan, R. Bio-Mitigation of Carbon Dioxide Using Microalgal Systems: Advances and Perspectives. Renew. Sustain. Energy Rev. 2017, 76, 1163–1175. [Google Scholar] [CrossRef]
  31. Kong, W.; Shen, B.; Lyu, H.; Kong, J.; Ma, J.; Wang, Z.; Feng, S. Review on Carbon Dioxide Fixation Coupled with Nutrients Removal from Wastewater by Microalgae. J. Clean. Prod. 2021, 292, 125975. [Google Scholar] [CrossRef]
  32. Zhang, S.; Liu, Z. Advances in the Biological Fixation of Carbon Dioxide by Microalgae. J. Chem. Technol. Biotechnol. 2021, 96, 1475–1495. [Google Scholar] [CrossRef]
  33. Wang, Y.; Stessman, D.J.; Spalding, M.H. The CO2 Concentrating Mechanism and Photosynthetic Carbon Assimilation in Limiting CO2: How Chlamydomonas Works against the Gradient. Plant J. 2015, 82, 429–448. [Google Scholar] [CrossRef] [PubMed]
  34. Ghoshal, D.; Goyal, A. Carbon Concentration Mechanism(s) in Unicellular Green Algae and Cyanobacteria. J. Plant Biochem. Biotechnol. 2001, 10, 83–90. [Google Scholar] [CrossRef]
  35. Price, G.D.; Badger, M.R.; Woodger, F.J.; Long, B.M. Advances in Understanding the Cyanobacterial CO2-Concentrating- Mechanism (CCM): Functional Components, Ci Transporters, Diversity, Genetic Regulation and Prospects for Engineering into Plants. J. Exp. Bot. 2008, 59, 1441–1461. [Google Scholar] [CrossRef] [PubMed]
  36. Liu, G.; Qiao, L.; Zhang, H.; Zhao, D.; Su, X. The Effects of Illumination Factors on the Growth and HCO3 Fixation of Microalgae in an Experiment Culture System. Energy 2014, 78, 40–47. [Google Scholar] [CrossRef]
  37. Kumar, V.; Nanda, M.; Kumar, S.; Chauhan, P.K. The Effects of Ultraviolet Radiation on Growth, Biomass, Lipid Accumulation and Biodiesel Properties of Microalgae. Energy Sources Part A Recover. Util. Environ. Eff. 2018, 40, 787–793. [Google Scholar] [CrossRef]
  38. Maltsev, Y.; Maltseva, K.; Kulikovskiy, M.; Maltseva, S. Influence of Light Conditions on Microalgae Growth and Content of Lipids, Carotenoids, and Fatty Acid Composition. Biology 2021, 10, 1060. [Google Scholar] [CrossRef]
  39. Sforza, E.; Gris, B.; De Farias Silva, C.E.; Morosinotto, T.; Bertucco, A. Effects of Light on Cultivation of Scenedesmus Obliquus in Batch and Continuous Flat Plate Photobioreactor. Chem. Eng. Trans. 2014, 38, 211–216. [Google Scholar]
  40. Kim, T.H.; Lee, Y.; Han, S.H.; Hwang, S.J. The Effects of Wavelength and Wavelength Mixing Ratios on Microalgae Growth and Nitrogen, Phosphorus Removal Using Scenedesmus sp. for Wastewater Treatment. Bioresour. Technol. 2013, 130, 75–80. [Google Scholar] [CrossRef]
  41. Lau, C.C.; Teh, K.Y.; Afifudeen, C.L.W.; Yee, W.; Aziz, A.; Cha, T.S. Bright as Day and Dark as Night: Light-Dependant Energy for Lipid Biosynthesis and Production in Microalgae. World J. Microbiol. Biotechnol. 2022, 38, 70. [Google Scholar] [CrossRef] [PubMed]
  42. Zhao, B.; Su, Y. Process Effect of Microalgal-Carbon Dioxide Fixation and Biomass Production: A Review. Renew. Sustain. Energy Rev. 2014, 31, 121–132. [Google Scholar] [CrossRef]
  43. Sachdeva, N.; Gupta, R.P.; Mathur, A.S.; Tuli, D.K. Enhanced Lipid Production in Thermo-Tolerant Mutants of Chlorella Pyrenoidosa NCIM 2738. Bioresour. Technol. 2016, 221, 576–587. [Google Scholar] [CrossRef]
  44. Kumar, A.; Ergas, S.; Yuan, X.; Sahu, A.; Zhang, Q.; Dewulf, J.; Malcata, F.X.; van Langenhove, H. Enhanced CO2 Fixation and Biofuel Production via Microalgae: Recent Developments and Future Directions. Trends Biotechnol. 2010, 28, 371–380. [Google Scholar] [CrossRef]
  45. Liang, Y.; Tang, J.; Luo, Y.; Kaczmarek, M.B.; Li, X.; Daroch, M. Thermosynechococcus as a Thermophilic Photosynthetic Microbial Cell Factory for CO2 Utilisation. Bioresour. Technol. 2019, 278, 255–265. [Google Scholar] [CrossRef]
  46. Ono, E.; Cuello, J.L. Carbon Dioxide Mitigation Using Thermophilic Cyanobacteria. Biosyst. Eng. 2007, 96, 129–134. [Google Scholar] [CrossRef]
  47. Ong, S.C.; Kao, C.Y.; Chiu, S.Y.; Tsai, M.T.; Lin, C.S. Characterization of the Thermal-Tolerant Mutants of Chlorella sp. with High Growth Rate and Application in Outdoor Photobioreactor Cultivation. Bioresour. Technol. 2010, 101, 2880–2883. [Google Scholar] [CrossRef]
  48. Hsueh, H.T.; Li, W.J.; Chen, H.H.; Chu, H. Carbon Bio-Fixation by Photosynthesis of Thermosynechococcus sp. CL-1 and Nannochloropsis oculta. J. Photochem. Photobiol. B Biol. 2009, 95, 33–39. [Google Scholar] [CrossRef]
  49. Li, S.; Li, X.; Ho, S.-H. Microalgae as a Solution of Third World Energy Crisis for Biofuels Production from Wastewater toward Carbon Neutrality: An Updated Review. Chemosphere 2022, 291, 132863. [Google Scholar] [CrossRef] [PubMed]
  50. Seyed Hosseini, N.; Shang, H.; Scott, J.A. Biosequestration of Industrial Off-Gas CO2 for Enhanced Lipid Productivity in Open Microalgae Cultivation Systems. Renew. Sustain. Energy Rev. 2018, 92, 458–469. [Google Scholar] [CrossRef]
  51. Razzak, S.A.; Ilyas, M.; Ali, S.A.M.; Hossain, M.M. Effects of CO2 Concentration and pH on Mixotrophic Growth of Nannochloropsis oculata. Appl. Biochem. Biotechnol. 2015, 176, 1290–1302. [Google Scholar] [CrossRef]
  52. Wang, Z.; Wen, X.; Xu, Y.; Ding, Y.; Geng, Y.; Li, Y. Maximizing CO2 Biofixation and Lipid Productivity of Oleaginous Microalga Graesiella sp. WBG-1 via CO2-Regulated pH in Indoor and Outdoor Open Reactors. Sci. Total Environ. 2018, 619–620, 827–833. [Google Scholar] [CrossRef]
  53. Li, S.; Song, C.; Li, M.; Chen, Y.; Lei, Z.; Zhang, Z. Effect of Different Nitrogen Ratio on the Performance of CO2 Absorption and Microalgae Conversion (CAMC) Hybrid System. Bioresour. Technol. 2020, 306, 123126. [Google Scholar] [CrossRef]
  54. Li, Q.; Fu, L.; Wang, Y.; Zhou, D.; Rittmann, B.E. Excessive Phosphorus Caused Inhibition and Cell Damage during Heterotrophic Growth of Chlorella regularis. Bioresour. Technol. 2018, 268, 266–270. [Google Scholar] [CrossRef]
  55. Razzak, S.A.; Ali, S.A.M.; Hossain, M.M.; deLasa, H. Biological CO2 Fixation with Production of Microalgae in Wastewater—A Review. Renew. Sustain. Energy Rev. 2017, 76, 379–390. [Google Scholar] [CrossRef]
  56. Anjos, M.; Fernandes, B.D.; Vicente, A.A.; Teixeira, J.A.; Dragone, G. Optimization of CO2 Bio-Mitigation by Chlorella vulgaris. Bioresour. Technol. 2013, 139, 149–154. [Google Scholar] [CrossRef][Green Version]
  57. Tang, D.; Han, W.; Li, P.; Miao, X.; Zhong, J. CO2 Biofixation and Fatty Acid Composition of Scenedesmus Obliquus and Chlorella Pyrenoidosa in Response to Different CO2 Levels. Bioresour. Technol. 2011, 102, 3071–3076. [Google Scholar] [CrossRef] [PubMed]
  58. Guo, Z.; Phooi, W.B.A.; Lim, Z.J.; Tong, Y.W. Control of CO2 Input Conditions during Outdoor Culture of Chlorella Vulgaris in Bubble Column Photobioreactors. Bioresour. Technol. 2015, 186, 238–245. [Google Scholar] [CrossRef] [PubMed]
  59. Moghimifam, R.; Niknam, V.; Ebrahimzadeh, H.; Hejazi, M.A. CO2 Biofixation and Fatty Acid Composition of Two Indigenous Dunaliella sp. Isolates (ABRIINW-CH2 and ABRIINW-SH33) in Response to Extremely High CO2 Levels. Bioprocess Biosyst. Eng. 2020, 43, 1587–1597. [Google Scholar] [CrossRef] [PubMed]
  60. Xia, A.; Hu, Z.; Liao, Q.; Huang, Y.; Zhu, X.; Ye, W.; Sun, Y. Enhancement of CO2 Transfer and Microalgae Growth by Perforated Inverted Arc Trough Internals in a Flat-Plate Photobioreactor. Bioresour. Technol. 2018, 269, 292–299. [Google Scholar] [CrossRef]
  61. Rodas-Zuluaga, L.I.; Castañeda-Hernández, L.; Castillo-Vacas, E.I.; Gradiz-Menjivar, A.; López-Pacheco, I.Y.; Castillo-Zacarías, C.; Boully, L.; Iqbal, H.M.N.; Parra-Saldívar, R. Bio-Capture and Influence of CO2 on the Growth Rate and Biomass Composition of the Microalgae Botryococcus Braunii and Scenedesmus sp. J. CO2 Util. 2021, 43, 101371. [Google Scholar] [CrossRef]
  62. Chiang, C.L.; Lee, C.M.; Chen, P.C. Utilization of the Cyanobacteria Anabaena sp. CH1 in Biological Carbon Dioxide Mitigation Processes. Bioresour. Technol. 2011, 102, 5400–5405. [Google Scholar] [CrossRef] [PubMed]
  63. Shen, Q.H.; Jiang, J.W.; Chen, L.P.; Cheng, L.H.; Xu, X.H.; Chen, H.L. Effect of Carbon Source on Biomass Growth and Nutrients Removal of Scenedesmus Obliquus for Wastewater Advanced Treatment and Lipid Production. Bioresour. Technol. 2015, 190, 257–263. [Google Scholar] [CrossRef]
  64. Liu, S.; Elvira, P.; Wang, Y.; Wang, W. Growth and Nutrient Utilization of Green Algae in Batch and Semicontinuous Autotrophic Cultivation Under High CO2 Concentration. Appl. Biochem. Biotechnol. 2019, 188, 836–853. [Google Scholar] [CrossRef] [PubMed]
  65. Song, C.; Qiu, Y.; Xie, M.; Liu, J.; Liu, Q.; Li, S.; Sun, L.; Wang, K.; Kansha, Y. Novel Regeneration and Utilization Concept Using Rich Chemical Absorption Solvent As a Carbon Source for Microalgae Biomass Production. Ind. Eng. Chem. Res. 2019, 58, 11720–11727. [Google Scholar] [CrossRef]
  66. de Morais, E.G.; Cassuriaga, A.P.A.; Callejas, N.; Martinez, N.; Vieitez, I.; Jachmanián, I.; Santos, L.O.; de Morais, M.G.; Costa, J.A.V. Evaluation of CO2 Biofixation and Biodiesel Production by Spirulina (Arthospira) Cultivated In Air-Lift Photobioreactor. Brazilian Arch. Biol. Technol. 2018, 61, 1–11. [Google Scholar] [CrossRef]
  67. Zhang, X.; Wei, X.; Hu, X.; Yang, Y.; Chen, X.; Tian, J.; Pan, T.; Ding, B. Effects of Different Concentrations of CO2 on Scenedesmus Obliquus to Overcome Sludge Extract Toxicity and Accumulate Biomass. Chemosphere 2022, 305, 135514. [Google Scholar] [CrossRef]
  68. Sheng, Y.; Mathimani, T.; Brindhadevi, K.; Basha, S.; Elfasakhany, A.; Xia, C.; Pugazhendhi, A. Combined Effect of CO2 Concentration and Low-Cost Urea Repletion/Starvation in Chlorella Vulgaris for Ameliorating Growth Metrics, Total and Non-Polar Lipid Accumulation and Fatty Acid Composition. Sci. Total Environ. 2022, 808, 151969. [Google Scholar] [CrossRef]
  69. Singh, H.; Rout, S.; Das, D. Dark Fermentative Biohydrogen Production Using Pretreated Scenedesmus Obliquus Biomass under an Integrated Paradigm of Biorefinery. Int. J. Hydrogen Energy 2022, 47, 102–116. [Google Scholar] [CrossRef]
  70. Li, D.; Wang, L.; Zhao, Q.; Wei, W.; Sun, Y. Improving High Carbon Dioxide Tolerance and Carbon Dioxide Fixation Capability of Chlorella sp. by Adaptive Laboratory Evolution. Bioresour. Technol. 2015, 185, 269–275. [Google Scholar] [CrossRef]
  71. Barahoei, M.; Hatamipour, M.S.; Afsharzadeh, S. CO2 Capturing by Chlorella Vulgaris in a Bubble Column Photo-Bioreactor; Effect of Bubble Size on CO2 Removal and Growth Rate. J. CO2 Util. 2020, 37, 9–19. [Google Scholar] [CrossRef]
  72. Kselíková, V.; Singh, A.; Bialevich, V.; Čížková, M.; Bišová, K. Improving Microalgae for Biotechnology—From Genetics to Synthetic Biology—Moving Forward but Not There Yet. Biotechnol. Adv. 2022, 58, 107885. [Google Scholar] [CrossRef] [PubMed]
  73. Nojima, D.; Ishizuka, Y.; Muto, M.; Ujiro, A.; Kodama, F.; Yoshino, T.; Maeda, Y.; Matsunaga, T.; Tanaka, T. Enhancement of Biomass and Lipid Productivities of Water Surface-Floating Microalgae by Chemical Mutagenesis. Mar. Drugs 2017, 15, 151. [Google Scholar] [CrossRef] [PubMed][Green Version]
  74. Tanadul, O.u.m.; Noochanong, W.; Jirakranwong, P.; Chanprame, S. EMS-Induced Mutation Followed by Quizalofop-Screening Increased Lipid Productivity in Chlorella sp. Bioprocess Biosyst. Eng. 2018, 41, 613–619. [Google Scholar] [CrossRef]
  75. Cheng, J.; Li, K.; Yang, Z.; Zhou, J.; Cen, K. Enhancing the Growth Rate and Astaxanthin Yield of Haematococcus Pluvialis by Nuclear Irradiation and High Concentration of Carbon Dioxide Stress. Bioresour. Technol. 2016, 204, 49–54. [Google Scholar] [CrossRef]
  76. Smalley, T.; Fields, F.J.; Berndt, A.J.E.; Ostrand, J.T.; Heredia, V.; Mayfield, S.P. Improving Biomass and Lipid Yields of Desmodesmus Armatus and Chlorella Vulgaris through Mutagenesis and High-Throughput Screening. Biomass Bioenergy 2020, 142, 105755. [Google Scholar] [CrossRef]
  77. Liu, L.; Diao, J.; Bi, Y.; Zeng, L.; Wang, F.; Chen, L.; Zhang, W. Rewiring the Metabolic Network to Increase Docosahexaenoic Acid Productivity in Crypthecodinium Cohnii by Fermentation Supernatant-Based Adaptive Laboratory Evolution. Front. Microbiol. 2022, 13, 824189. [Google Scholar] [CrossRef]
  78. Wei, L.; Wang, Q.; Xin, Y.; Lu, Y.; Xu, J. Enhancing Photosynthetic Biomass Productivity of Industrial Oleaginous Microalgae by Overexpression of RuBisCO Activase. Algal Res. 2017, 27, 366–375. [Google Scholar] [CrossRef]
  79. Baek, K.; Kim, D.H.; Jeong, J.; Sim, S.J.; Melis, A.; Kim, J.S.; Jin, E.; Bae, S. DNA-Free Two-Gene Knockout in Chlamydomonas Reinhardtii via CRISPR-Cas9 Ribonucleoproteins. Sci. Rep. 2016, 6, 30620. [Google Scholar] [CrossRef]
  80. Cheng, J.; Zhu, Y.; Zhang, Z.; Yang, W. Modification and Improvement of Microalgae Strains for Strengthening CO2 Fixation from Coal-Fired Flue Gas in Power Plants. Bioresour. Technol. 2019, 291, 121850. [Google Scholar] [CrossRef] [PubMed]
  81. Tharek, A.; Yahya, A.; Salleh, M.M.; Jamaluddin, H.; Yoshizaki, S.; Hara, H.; Iwamoto, K.; Suzuki, I.; Mohamad, S.E. Improvement and Screening of Astaxanthin Producing Mutants of Newly Isolated Coelastrum sp. Using Ethyl Methane Sulfonate Induced Mutagenesis Technique. Biotechnol. Rep. 2021, 32, e00673. [Google Scholar] [CrossRef] [PubMed]
  82. Kuo, E.Y.; Yang, R.; Chin, Y.Y.; Chien, Y.; Chen, Y.C.; Wei, C.; Kao, L.; Chang, Y.; Li, Y.; Chen, T.; et al. Multiomics Approaches and Genetic Engineering of Metabolism for Improved Biorefinery and Wastewater Treatment in Microalgae. Biotechnol. J. 2022, 17, e2100603. [Google Scholar] [CrossRef] [PubMed]
  83. Araújo, R.G.; Alcantar-Rivera, B.; Meléndez-Sánchez, E.R.; Martínez-Prado, M.A.; Sosa-Hernández, J.E.; Iqbal, H.M.N.; Parra-Saldivar, R.; Martínez-Ruiz, M. Effects of UV and UV-Vis Irradiation on the Production of Microalgae and Macroalgae: New Alternatives to Produce Photobioprotectors and Biomedical Compounds. Molecules 2022, 27, 5334. [Google Scholar] [CrossRef] [PubMed]
  84. Moha-León, J.D.; Pérez-Legaspi, I.A.; Ortega-Clemente, L.A.; Rubio-Franchini, I.; Ríos-Leal, E. Improving the Lipid Content of Nannochloropsis Oculata by a Mutation-Selection Program Using UV Radiation and Quizalofop. J. Appl. Phycol. 2019, 31, 191–199. [Google Scholar] [CrossRef]
  85. Cheng, J.; Huang, Y.; Feng, J.; Sun, J.; Zhou, J.; Cen, K. Mutate Chlorella sp. by Nuclear Irradiation to Fix High Concentrations of CO2. Bioresour. Technol. 2013, 136, 496–501. [Google Scholar] [CrossRef]
  86. Zhang, B.; Wu, J.; Meng, F. Adaptive Laboratory Evolution of Microalgae: A Review of the Regulation of Growth, Stress Resistance, Metabolic Processes, and Biodegradation of Pollutants. Front. Microbiol. 2021, 12, 737248. [Google Scholar] [CrossRef]
  87. Arora, N.; Philippidis, G.P. Microalgae Strain Improvement Strategies: Random Mutagenesis and Adaptive Laboratory Evolution. Trends Plant Sci. 2021, 26, 1199–1200. [Google Scholar] [CrossRef]
  88. Wang, J.; Wang, Y.; Wu, Y.; Fan, Y.; Zhu, C.; Fu, X.; Chu, Y.; Chen, F.; Sun, H.; Mou, H. Application of Microalgal Stress Responses in Industrial Microalgal Production Systems. Mar. Drugs 2022, 20, 30. [Google Scholar] [CrossRef]
  89. Zhao, Q.; Huang, H. Adaptive Evolution Improves Algal Strains for Environmental Remediation. Trends Biotechnol. 2021, 39, 112–115. [Google Scholar] [CrossRef]
  90. Sun, X.M.; Ren, L.J.; Ji, X.J.; Chen, S.L.; Guo, D.S.; Huang, H. Adaptive Evolution of Schizochytrium sp. by Continuous High Oxygen Stimulations to Enhance Docosahexaenoic Acid Synthesis. Bioresour. Technol. 2016, 211, 374–381. [Google Scholar] [CrossRef][Green Version]
  91. Åhlén, M.; Cheung, O.; Xu, C. Low-Concentration CO2 Capture Using Metal–Organic Frameworks—Current Status and Future Perspectives. Dalt. Trans. 2023, 52, 1841–1856. [Google Scholar] [CrossRef] [PubMed]
  92. Thomas, D.M.; Mechery, J.; Paulose, S.V. Carbon Dioxide Capture Strategies from Flue Gas Using Microalgae: A Review. Environ. Sci. Pollut. Res. 2016, 23, 16926–16940. [Google Scholar] [CrossRef] [PubMed]
  93. Tsai, D.D.W.; Chen, P.H.; jung Chou, C.M.; Hsu, C.F.; Ramaraj, R. Carbon Sequestration by Alga Ecosystems. Ecol. Eng. 2015, 84, 386–389. [Google Scholar] [CrossRef]
  94. Mondal, M.; Goswami, S.; Ghosh, A.; Oinam, G.; Tiwari, O.N.; Das, P.; Gayen, K.; Mandal, M.K.; Halder, G.N. Production of Biodiesel from Microalgae through Biological Carbon Capture: A Review. 3 Biotech 2017, 7, 99. [Google Scholar] [CrossRef] [PubMed][Green Version]
  95. Wang, B.; Li, Y.; Wu, N.; Lan, C.Q. CO2 Bio-Mitigation Using Microalgae. Appl. Microbiol. Biotechnol. 2008, 79, 707–718. [Google Scholar] [CrossRef]
  96. Suparmaniam, U.; Lam, M.K.; Uemura, Y.; Lim, J.W.; Lee, K.T.; Shuit, S.H. Insights into the Microalgae Cultivation Technology and Harvesting Process for Biofuel Production: A Review. Renew. Sustain. Energy Rev. 2019, 115, 109361. [Google Scholar] [CrossRef]
  97. Sen Tan, J.; Lee, S.Y.; Chew, K.W.; Lam, M.K.; Lim, J.W.; Ho, S.-H.; Show, P.L. A Review on Microalgae Cultivation and Harvesting, and Their Biomass Extraction Processing Using Ionic Liquids. Bioengineered 2020, 11, 116–129. [Google Scholar] [CrossRef][Green Version]
  98. McGinn, P.J.; Dickinson, K.E.; Bhatti, S.; Frigon, J.C.; Guiot, S.R.; O’Leary, S.J.B. Integration of Microalgae Cultivation with Industrial Waste Remediation for Biofuel and Bioenergy Production: Opportunities and Limitations. Photosynth. Res. 2011, 109, 231–247. [Google Scholar] [CrossRef]
  99. Kumar, S.; Aswar, D. Recent Advances in Thin Films; Materials Horizons: From Nature to Nanomaterials; Springer: Singapore, 2020; ISBN 978-981-15-6116-0. [Google Scholar]
  100. Van Den Hende, S.; Vervaeren, H.; Boon, N. Flue Gas Compounds and Microalgae: (Bio-)Chemical Interactions Leading to Biotechnological Opportunities. Biotechnol. Adv. 2012, 30, 1405–1424. [Google Scholar] [CrossRef] [PubMed]
  101. Mallapragada, D.S.; Singh, N.R.; Curteanu, V.; Agrawal, R. Sun-to-Fuel Assessment of Routes for Fixing CO2 as Liquid Fuel. Ind. Eng. Chem. Res. 2013, 52, 5136–5144. [Google Scholar] [CrossRef]
  102. Vuppaladadiyam, A.K.; Yao, J.G.; Florin, N.; George, A.; Wang, X.; Labeeuw, L.; Jiang, Y.; Davis, R.W.; Abbas, A.; Ralph, P.; et al. Impact of Flue Gas Compounds on Microalgae and Mechanisms for Carbon Assimilation and Utilization. ChemSusChem 2018, 11, 334–355. [Google Scholar] [CrossRef]
  103. Yen, H.W.; Ho, S.H.; Chen, C.Y.; Chang, J.S. CO2, NOx and SOx Removal from Flue Gas via Microalgae Cultivation: A Critical Review. Biotechnol. J. 2015, 10, 829–839. [Google Scholar] [CrossRef]
  104. Duarte, J.H.; de Morais, E.G.; Radmann, E.M.; Costa, J.A.V. Biological CO2 Mitigation from Coal Power Plant by Chlorella Fusca and Spirulina sp. Bioresour. Technol. 2017, 234, 472–475. [Google Scholar] [CrossRef]
  105. Molazadeh, M.; Ahmadzadeh, H.; Pourianfar, H.R.; Lyon, S.; Rampelotto, P.H. The Use of Microalgae for Coupling Wastewater Treatment With CO2 Biofixation. Front. Bioeng. Biotechnol. 2019, 7, 42. [Google Scholar] [CrossRef] [PubMed][Green Version]
  106. Li, G.; Yang, T.; Xiao, W.; Wu, J.; Xu, F.; Li, L.; Gao, F.; Huang, Z. Sustainable Environmental Assessment of Waste-to-Energy Practices: Co-Pyrolysis of Food Waste and Discarded Meal Boxes. Foods 2022, 11, 3840. [Google Scholar] [CrossRef] [PubMed]
  107. Song, C.; Han, X.; Qiu, Y.; Liu, Z.; Li, S.; Kitamura, Y. Microalgae Carbon Fixation Integrated with Organic Matters Recycling from Soybean Wastewater: Effect of pH on the Performance of Hybrid System. Chemosphere 2020, 248, 126094. [Google Scholar] [CrossRef] [PubMed]
  108. Omar Faruque, M.; Ilyas, M.; Mozahar Hossain, M.; Abdur Razzak, S. Influence of Nitrogen to Phosphorus Ratio and CO2 Concentration on Lipids Accumulation of Scenedesmus Dimorphus for Bioenergy Production and CO2 Biofixation. Chem. Asian J. 2020, 15, 4307–4320. [Google Scholar] [CrossRef]
  109. Hu, X.; Song, C.; Mu, H.; Liu, Z.; Kitamura, Y. Optimization of Simultaneous Soybean Processing Wastewater Treatment and Flue Gas CO2 Fixation via Chlorella sp. L166 Cultivation. J. Environ. Chem. Eng. 2020, 8, 103960. [Google Scholar] [CrossRef]
  110. Li, G.; Hu, R.; Wang, N.; Yang, T.; Xu, F.; Li, J.; Wu, J.; Huang, Z.; Pan, M.; Lyu, T. Cultivation of Microalgae in Adjusted Wastewater to Enhance Biofuel Production and Reduce Environmental Impact: Pyrolysis Performances and Life Cycle Assessment. J. Clean. Prod. 2022, 355, 131768. [Google Scholar] [CrossRef]
  111. Ahmad, A.L.; Yasin, N.H.M.; Derek, C.J.C.; Lim, J.K. Microalgae as a Sustainable Energy Source for Biodiesel Production: A Review. Renew. Sustain. Energy Rev. 2011, 15, 584–593. [Google Scholar] [CrossRef]
  112. Villaro, S.; Ciardi, M.; Morillas-españa, A.; Sánchez-Zurano, A.; Acién-Fernández, G.; Lafarga, T. Trends and Industrial Use as Food. Foods 2021, 10, 2303. [Google Scholar] [CrossRef] [PubMed]
  113. Martínez Andrade, K.; Lauritano, C.; Romano, G.; Ianora, A. Marine Microalgae with Anti-Cancer Properties. Mar. Drugs 2018, 16, 165. [Google Scholar] [CrossRef] [PubMed][Green Version]
  114. Liang, Z.C.; Liang, M.H.; Jiang, J.G. Transgenic Microalgae as Bioreactors. Crit. Rev. Food Sci. Nutr. 2020, 60, 3195–3213. [Google Scholar] [CrossRef]
  115. Muñoz, C.F.; Südfeld, C.; Naduthodi, M.I.S.; Weusthuis, R.A.; Barbosa, M.J.; Wijffels, R.H.; D’Adamo, S. Genetic Engineering of Microalgae for Enhanced Lipid Production. Biotechnol. Adv. 2021, 52, 107836. [Google Scholar] [CrossRef]
  116. Mavrommati, M.; Daskalaki, A.; Papanikolaou, S.; Aggelis, G. Adaptive Laboratory Evolution Principles and Applications in Industrial Biotechnology. Biotechnol. Adv. 2022, 54, 107795. [Google Scholar] [CrossRef] [PubMed]
  117. Rajkumar, R.; Takriff, M.S.; Veeramuthu, A. Technical Insights into Carbon Dioxide Sequestration by Microalgae: A Biorefinery Approach towards Sustainable Environment. Biomass Convers. Bioref. 2022. [Google Scholar] [CrossRef]
  118. Marchão, L.; Fernandes, J.R.; Sampaio, A.; Peres, J.A.; Tavares, P.B.; Lucas, M.S. Microalgae and Immobilized TiO2/UV-A LEDs as a Sustainable Alternative for Winery Wastewater Treatment. Water Res. 2021, 203, 117464. [Google Scholar] [CrossRef]
  119. Huang, G.; Chen, F.; Kuang, Y.; He, H.; Qin, A. Current Techniques of Growing Algae Using Flue Gas from Exhaust Gas Industry: A Review. Appl. Biochem. Biotechnol. 2016, 178, 1220–1238. [Google Scholar] [CrossRef]
  120. Chia, S.R.; Chew, K.W.; Leong, H.Y.; Ho, S.H.; Munawaroh, H.S.H.; Show, P.L. CO2 Mitigation and Phycoremediation of Industrial Flue Gas and Wastewater via Microalgae-Bacteria Consortium: Possibilities and Challenges. Chem. Eng. J. 2021, 425, 131436. [Google Scholar] [CrossRef]
  121. Ma, Z.; Cheah, W.Y.; Ng, I.S.; Chang, J.S.; Zhao, M.; Show, P.L. Microalgae-Based Biotechnological Sequestration of Carbon Dioxide for Net Zero Emissions. Trends Biotechnol. 2022, 40, 1439–1453. [Google Scholar] [CrossRef]
  122. Chisti, Y. Biodiesel from Microalgae. Biotechnol. Adv. 2007, 25, 294–306. [Google Scholar] [CrossRef]
  123. Liang, M.H.; Wang, L.; Wang, Q.; Zhu, J.; Jiang, J.G. High-Value Bioproducts from Microalgae: Strategies and Progress. Crit. Rev. Food Sci. Nutr. 2019, 59, 2423–2441. [Google Scholar] [CrossRef] [PubMed]
  124. Park, S.; Nguyen, T.H.T.; Jin, E.S. Improving Lipid Production by Strain Development in Microalgae: Strategies, Challenges and Perspectives. Bioresour. Technol. 2019, 292, 121953. [Google Scholar] [CrossRef] [PubMed]
  125. Mohsenpour, S.F.; Hennige, S.; Willoughby, N.; Adeloye, A.; Gutierrez, T. Integrating Micro-Algae into Wastewater Treatment: A Review. Sci. Total Environ. 2021, 752, 142168. [Google Scholar] [CrossRef] [PubMed]
  126. Zhang, D.; An, S.; Yao, R.; Fu, W.; Han, Y.; Du, M.; Chen, Z.; Lei, A.; Wang, J. Life Cycle Assessment of Auto-Tropically Cultivated Economic Microalgae for Final Products Such as Food, Total Fatty Acids, and Bio-Oil. Front. Mar. Sci. 2022, 9, 990635. [Google Scholar] [CrossRef]
  127. Last, G.V.; Schmick, M.T. A Review of Major Non-Power-Related Carbon Dioxide Stream Compositions. Environ. Earth Sci. 2015, 74, 1189–1198. [Google Scholar] [CrossRef]
  128. De Coninck, H.; Benson, S.M. Carbon Dioxide Capture and Storage: Issues and Prospects. Annu. Rev. Environ. Resour. 2014, 39, 243–270. [Google Scholar] [CrossRef]
  129. Yu, S.; Zhao, Q.; Miao, X.; Shi, J. Enhancement of Lipid Production in Low-Starch Mutants Chlamydomonas Reinhardtii by Adaptive Laboratory Evolution. Bioresour. Technol. 2013, 147, 499–507. [Google Scholar] [CrossRef]
  130. Ren, L.J.; Huang, H.; Xiao, A.H.; Lian, M.; Jin, L.J.; Ji, X.J. Enhanced Docosahexaenoic Acid Production by Reinforcing Acetyl-CoA and NADPH Supply in Schizochytrium sp. HX-308. Bioprocess Biosyst. Eng. 2009, 32, 837–843. [Google Scholar] [CrossRef]
  131. Sun, X.M.; Ren, L.J.; Bi, Z.Q.; Ji, X.J.; Zhao, Q.Y.; Huang, H. Adaptive Evolution of Microalgae Schizochytrium sp. under High Salinity Stress to Alleviate Oxidative Damage and Improve Lipid Biosynthesis. Bioresour. Technol. 2018, 267, 438–444. [Google Scholar] [CrossRef]
  132. Zhou, L.; Cheng, D.; Wang, L.; Gao, J.; Zhao, Q.; Wei, W.; Sun, Y. Comparative Transcriptomic Analysis Reveals Phenol Tolerance Mechanism of Evolved Chlorella Strain. Bioresour. Technol. 2017, 227, 266–272. [Google Scholar] [CrossRef]
  133. Wang, L.; Xue, C.; Wang, L.; Zhao, Q.; Wei, W.; Sun, Y. Strain Improvement of Chlorella sp. for Phenol Biodegradation by Adaptive Laboratory Evolution. Bioresour. Technol. 2016, 205, 264–268. [Google Scholar] [CrossRef] [PubMed]
  134. Wang, X.; Luo, S.W.; Luo, W.; Yang, W.D.; Liu, J.S.; Li, H.Y. Adaptive Evolution of Microalgal Strains Empowered by Fulvic Acid for Enhanced Polyunsaturated Fatty Acid Production. Bioresour. Technol. 2019, 277, 204–210. [Google Scholar] [CrossRef] [PubMed]
  135. Barten, R.; van Workum, D.J.M.; de Bakker, E.; Risse, J.; Kleisman, M.; Navalho, S.; Smit, S.; Wijffels, R.H.; Nijveen, H.; Barbosa, M.J. Genetic Mechanisms Underlying Increased Microalgal Thermotolerance, Maximal Growth Rate, and Yield on Light Following Adaptive Laboratory Evolution. BMC Biol. 2022, 20, 242. [Google Scholar] [CrossRef] [PubMed]
  136. Hu, L.; He, J.; Dong, M.; Tang, X.; Jiang, P.; Lei, A.; Wang, J. Divergent Metabolic and Transcriptomic Responses of Synechocystis sp. PCC 6803 to Salt Stress after Adaptive Laboratory Evolution. Algal Res. 2020, 47, 101856. [Google Scholar] [CrossRef]
  137. Saini, P.; Beniwal, A.; Kokkiligadda, A.; Vij, S. Evolutionary Adaptation of Kluyveromyces Marxianus Strain for Efficient Conversion of Whey Lactose to Bioethanol. Process Biochem. 2017, 62, 69–79. [Google Scholar] [CrossRef]
  138. Maneechote, W.; Cheirsilp, B. Stepwise-Incremental Physicochemical Factors Induced Acclimation and Tolerance in Oleaginous Microalgae to Crucial Outdoor Stresses and Improved Properties as Biodiesel Feedstocks. Bioresour. Technol. 2021, 328, 124850. [Google Scholar] [CrossRef]
  139. Hu, X.; Tang, X.; Bi, Z.; Zhao, Q.; Ren, L. Adaptive Evolution of Microalgae Schizochytrium sp. under High Temperature for Efficient Production of Docosahexaeonic Acid. Algal Res. 2021, 54, 102212. [Google Scholar] [CrossRef]
  140. Arora, N.; Lo, E.; Philippidis, G.P. A Two-Prong Mutagenesis and Adaptive Evolution Strategy to Enhance the Temperature Tolerance and Productivity of Nannochloropsis oculata. Bioresour. Technol. 2022, 364, 128101. [Google Scholar] [CrossRef]
  141. Li, X.; Yuan, Y.; Cheng, D.; Gao, J.; Kong, L.; Zhao, Q.; Wei, W.; Sun, Y. Exploring Stress Tolerance Mechanism of Evolved Freshwater Strain Chlorella sp. S30 under 30 g/L Salt. Bioresour. Technol. 2018, 250, 495–504. [Google Scholar] [CrossRef]
  142. Han, S.I.; Kim, S.; Lee, C.; Choi, Y.E. Blue-Red LED Wavelength Shifting Strategy for Enhancing Beta-Carotene Production from Halotolerant Microalga, Dunaliella salina. J. Microbiol. 2019, 57, 101–106. [Google Scholar] [CrossRef] [PubMed]
  143. Tan, X.; Chu, H.; Zhang, Y.; Yang, L.; Zhao, F.; Zhou, X. Chlorella Pyrenoidosa Cultivation Using Anaerobic Digested Starch Processing Wastewater in an Airlift Circulation Photobioreactor. Bioresour. Technol. 2014, 170, 538–548. [Google Scholar] [CrossRef]
  144. Wen, Y.; He, Y.; Ji, X.; Li, S.; Chen, L.; Zhou, Y.; Wang, M.; Chen, B. Isolation of an Indigenous Chlorella Vulgaris from Swine Wastewater and Characterization of Its Nutrient Removal Ability in Undiluted Sewage. Bioresour. Technol. 2017, 243, 247–253. [Google Scholar] [CrossRef]
  145. Yao, L.; Shi, J.; Miao, X. Mixed Wastewater Coupled with CO2 for Microalgae Culturing and Nutrient Removal. PLoS ONE 2015, 10, e0139117. [Google Scholar] [CrossRef][Green Version]
  146. Taghavijeloudar, M.; Yaqoubnejad, P.; Amini-Rad, H.; Park, J. Optimization of Cultivation Condition of Newly Isolated Strain Chlorella Sorokiniana Pa.91 for CO2 Bio-Fixation and Nutrients Removal from Wastewater: Impact of Temperature and Light Intensity. Clean Technol. Environ. Policy 2021, 25, 589–601. [Google Scholar] [CrossRef]
  147. Chaudhary, R.; Dikshit, A.K.; Tong, Y.W. Carbon-Dioxide Biofixation and Phycoremediation of Municipal Wastewater Using Chlorella Vulgaris and Scenedesmus obliquus. Environ. Sci. Pollut. Res. 2018, 25, 20399–20406. [Google Scholar] [CrossRef] [PubMed]
  148. Shin, D.Y.; Cho, H.U.; Utomo, J.C.; Choi, Y.N.; Xu, X.; Park, J.M. Biodiesel Production from Scenedesmus Bijuga Grown in Anaerobically Digested Food Wastewater Effluent. Bioresour. Technol. 2015, 184, 215–221. [Google Scholar] [CrossRef]
  149. Ma, S.; Yu, Y.; Cui, H.; Yadav, R.S.; Li, J.; Feng, Y. Unsterilized Sewage Treatment and Carbohydrate Accumulation in Tetradesmus obliquus PF3 with CO2 Supplementation. Algal Res. 2020, 45, 101741. [Google Scholar] [CrossRef]
  150. Razzak, S.A. In Situ Biological CO2 Fixation and Wastewater Nutrient Removal with Neochloris Oleoabundans in Batch Photobioreactor. Bioprocess Biosyst. Eng. 2019, 42, 93–105. [Google Scholar] [CrossRef] [PubMed]
  151. Han, W.; Jin, W.; Li, Z.; Wei, Y.; He, Z.; Chen, C.; Qin, C.; Chen, Y.; Tu, R.; Zhou, X. Cultivation of Microalgae for Lipid Production Using Municipal Wastewater. Process Saf. Environ. Prot. 2021, 155, 155–165. [Google Scholar] [CrossRef]
  152. Xu, X.; Shen, Y.; Chen, J. Cultivation of Scenedesmus Dimorphus for C/N/P Removal and Lipid Production. Electron. J. Biotechnol. 2015, 18, 46–50. [Google Scholar] [CrossRef][Green Version]
  153. Song, C.; Hu, X.; Liu, Z.; Li, S.; Kitamura, Y. Combination of Brewery Wastewater Purification and CO2 Fixation with Potential Value-Added Ingredients Production via Different Microalgae Strains Cultivation. J. Clean. Prod. 2020, 268, 122332. [Google Scholar] [CrossRef]
  154. Hariz, H.B.; Takriff, M.S.; Ba-Abbad, M.M.; Mohd Yasin, N.H.; Mohd Hakim, N.I.N. CO2 Fixation Capability of Chlorella sp. and Its Use in Treating Agricultural Wastewater. J. Appl. Phycol. 2018, 30, 3017–3027. [Google Scholar] [CrossRef]
  155. Ma, C.; Wen, H.; Xing, D.; Pei, X.; Zhu, J.; Ren, N.; Liu, B. Molasses Wastewater Treatment and Lipid Production at Low Temperature Conditions by a Microalgal Mutant Scenedesmus sp. Z-4. Biotechnol. Biofuels 2017, 10, 111. [Google Scholar] [CrossRef][Green Version]
  156. Li, F.; Amenorfenyo, D.K.; Zhang, Y.; Zhang, N.; Li, C.; Huang, X. Cultivation of Chlorella Vulgaris in Membrane-Treated Industrial Distillery Wastewater: Growth and Wastewater Treatment. Front. Environ. Sci. 2021, 9, 770633. [Google Scholar] [CrossRef]
  157. Huy, M.; Kumar, G.; Kim, H.W.; Kim, S.H. Photoautotrophic Cultivation of Mixed Microalgae Consortia Using Various Organic Waste Streams towards Remediation and Resource Recovery. Bioresour. Technol. 2018, 247, 576–581. [Google Scholar] [CrossRef]
  158. Mata, T.M.; Melo, A.C.; Simões, M.; Caetano, N.S. Parametric Study of a Brewery Effluent Treatment by Microalgae Scenedesmus obliquus. Bioresour. Technol. 2012, 107, 151–158. [Google Scholar] [CrossRef]
Figure 1. C3 cycle.
Figure 1. C3 cycle.
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Figure 2. The technical flow chart of microalgae carbon sequestration.
Figure 2. The technical flow chart of microalgae carbon sequestration.
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Figure 3. The simplified model of CCM.
Figure 3. The simplified model of CCM.
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Figure 4. Different growth environment conditions affect the growth rate of microalgae.
Figure 4. Different growth environment conditions affect the growth rate of microalgae.
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Figure 5. Mechanism of adsorption of settling phosphorus by microalgae.
Figure 5. Mechanism of adsorption of settling phosphorus by microalgae.
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Figure 6. Strategies for improving photosynthetic efficiency in microalgae.
Figure 6. Strategies for improving photosynthetic efficiency in microalgae.
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Figure 7. Mechanism of the inhibition of microalgae CO2 fixation by SOX.
Figure 7. Mechanism of the inhibition of microalgae CO2 fixation by SOX.
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Table 1. The optimal growth temperature for different species of microalgae.
Table 1. The optimal growth temperature for different species of microalgae.
SpeciesCulture MediumOptimal Growth Temperature (°C)Average Specific Growth (d−1)Ref.
Chlorella pyrenoidosa M18BG11370.70[43]
Thermosynechococcus elongatus PKUAC-SCTE542BG11550.22[45]
Chlorogleopsis sp.BG11500.14[46]
Chlorella sp. MT-15Artificial sea water30Approximately 0.80[47]
Chlorella sp. MT-7Artificial sea water30Approximately 0.60
Thermosynechococcus sp. CL-1Modified Fitzgerald502.70[48]
Nannochloropsis sp. OcultaModified Fitzgerald301.60
Table 2. Growth rates of different species of microalgae at different CO2 concentrations.
Table 2. Growth rates of different species of microalgae at different CO2 concentrations.
SpeciesCO2 (%)Culture MediumAeration Rate (vvm)CO2 Fixation Rate (mg/L/d)Biomass Yield (g/L)Biomass Productivity (mg/L/d)Ref.
Chlorella vulgaris2% constantLiquid medium of 3N-BBM+V0.441102.593530[58]
4% provided intermittently45002.623410
Spirulina platensis5Zarrouk medium0.1178.461.75-[43]
Dunaliella sp. ABRIINW-SH3310Modified Johnson medium3455.742.98248.60[59]
Dunaliella sp. ABRIINW-CH210423.192.77230.83
Chlorella vulgaris FACHB-3115Modified BG110.02878.403.35-[60]
Botryococcus braunii0.03BG110.1-0.64-[61]
Scenedesmus sp.0.03BG110.1-0.72-
Anabaena sp. CH110Arnon medium0.410101.16-[62]
Scenedesmus obliquus5Selenite enrichment medium-577.60--[63]
Chlorella protothecoides20BG11-3701.55190[64]
Chlorella vulgaris P126.50-0.522909.971330[56]
Chlorella sp. L385BG11--0.60-[65]
Spirulina sp. LEB 1810Zarrouk medium-1601.0720[66]
Scenedesmus obliquus (FACHB-13)15BG111-1.61-[67]
Chlorella vulgaris15BG11-1201.83144[68]
Scenedesmus obliquus UTEX 3935Airlift photobioreactor0.43727.70-405.70[69]
Chlorella sp. AE 1030%BG11--3.68-[70]
Table 3. Application of strategies to improve the photosynthetic efficiency of microalgae.
Table 3. Application of strategies to improve the photosynthetic efficiency of microalgae.
Random mutagenesisChemical mutagenesisChlorococcum sp. FFG039The FFG039 PM exhibited 1.7-fold and 1.9-fold higher biomass and lipid productivities than those of the wild type.[73]
Chlorella sp.The E100-30-60 showed that the highest biomass yield and biomass productivity were 111 and 110% higher than the wild type, respectively.[74]
Physical mutagenesisHaematococcus pluvialisThe average specific growth rate of Haematococcus pluvialis mutated with 4000 Gy γ-ray irradiation was increased by 15% compared with the original strain with air aeration.[75]
Chlorella vulgarisThe resulting mutant resulted in a 33% increase in lipid yield.[76]
ALEChlorella sp.The maximal biomass concentration of AE10 was 3.68 ± 0.08 g/L in 30% CO2, which was 2.94 fold compared to the original strain.[70]
Crypthecodinium cohnii ATCC 30556The cell growth of the evolved strain (FS280) was increased by 161.87%.[77]
Genetic engineeringNannochloropsis oceanicaThe growth rate of mutants was enhanced by 32%, and biomass accumulation by 46%.[78]
Chlamydomonas reinhardtiiThe strain improved photosynthetic productivity.[79]
Table 4. Comparison of various carbon capture methods.
Table 4. Comparison of various carbon capture methods.
PhysicalGeologic injectionSeparate and capture CO2, transport it to a storage location, and inject it deep underground for long-term isolation from the atmosphere
Take use of space available
High costs
Special geological requirements
Oceanic injectionInjection of CO2 into deep ocean
Significant capacity to store CO2
High costs
Low storage permanence
Considerable ecological impacts
ChemicalChemical absorptionChemical absorption and desorption concept, determined by solubility of CO2
Environmentally safer
Capture efficiency to 90%
Inefficient CO2 capture capacity
High evaporation loss of solvent
Poor thermal stability,
Equipment corrosion
Mineral carbonationCO2 reacts with calcium- or magnesium-bearing rocks to form magnesite or calcite
CO2 is converted to a solid substrate that can be reused as a building material or disposed of in surface facilities.
Need for a significant amount of reagent
BiologicalForest plantingAbsorption of CO2 through the photosynthesis of the trees
Significant social benefits
Environmentally friendly
Large land area requirement
Low carbon fixation efficiency compared to microalgae
Microalgae carbon fixationCarbon sequestration by microalgal photosynthesis
Environmentally friendly
Economically feasible
Plant in seawater or wastewater and require no a large area of soil resources
CO2 fixation more efficiently than land plants
Sensitive to living conditions (e.g., pH, toxic substances, and CO2 concentrations)
Improve the cost performance of the cultivation
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Li, G.; Xiao, W.; Yang, T.; Lyu, T. Optimization and Process Effect for Microalgae Carbon Dioxide Fixation Technology Applications Based on Carbon Capture: A Comprehensive Review. C 2023, 9, 35.

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Li G, Xiao W, Yang T, Lyu T. Optimization and Process Effect for Microalgae Carbon Dioxide Fixation Technology Applications Based on Carbon Capture: A Comprehensive Review. C. 2023; 9(1):35.

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Li, Gang, Wenbo Xiao, Tenglun Yang, and Tao Lyu. 2023. "Optimization and Process Effect for Microalgae Carbon Dioxide Fixation Technology Applications Based on Carbon Capture: A Comprehensive Review" C 9, no. 1: 35.

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