Research and Product Development of Microalgae for Food and Human Health

A special issue of Foods (ISSN 2304-8158). This special issue belongs to the section "Food Nutrition".

Deadline for manuscript submissions: closed (25 May 2022) | Viewed by 48369

Special Issue Editors


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Guest Editor
National Research Council Canada, Ottawa, ON, Canada
Interests: nutrition; functional ingredient; protein quality assessment; metabolic health; immunomodulation; inflammation; oxidative stress

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Guest Editor
Department of Nutrition, University of Tennessee, Knoxville, TN, USA
Interests: functional foods; nutrients; bioactive ingredients/compounds in the intervention of chronic metabolic diseases; roles of micronutrients in the glucose and fatty acid metabolism; nutrient-gene interactions

Special Issue Information

Dear Colleagues,

There are numerous species of microalgae, which produce very different amounts of specific nutrients, such as protein, amino acids, oil especially omega-3 EPA and DHA, carotenoids, and pigments. In addition to the genetic traits, microalgae alter the metabolism and thus the nutrient contents in response to environmental change. These unique characteristics of microalgae have a huge potential to be used as a biology system and technology platform to produce target compounds and biomolecules to meet the market demand for special ingredients for food, nutraceutical, cosmetic, and medical/pharmaceutical applications towards human health. However, research and product development on microalgae are still at an early stage. This Special Issue is intended to promote research on microalgae by attracting and publishing high-quality research papers. Researchers are highly encouraged to submit your research articles in areas that include, but not limited to, in vitro and in vivo studies as well as human clinical trials on the health benefits, mechanisms of action, and safety/toxicity of microalgae, production of a specific compound or nutrient via environmental manipulation and/or bioengineering technology, method development and improvement on extraction and purification of specific compounds and nutrients, and the quality assessment of nutrients. As, in general, the cell wall of microalgae is not readily broken up by the physical, chemical, and enzymatic actions in the digestive system after ingestion, the development of processing method and technology for the improvement of digestibility and utilization of nutrients are strongly are also of particular interest.

Dr. Yanwen Wang
Prof. Dr. Guoxun Chen
Guest Editors

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Keywords

  • microalgae
  • food
  • functional ingredient
  • protein
  • amino acid
  • antioxidant
  • extraction and purification
  • bioengineering
  • growth condition manipulation
  • human health

Published Papers (13 papers)

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Research

Jump to: Review

17 pages, 7103 KiB  
Article
Comparison of Production and Fluorescence Characteristics of Phycoerythrin from Three Strains of Porphyridium
by Chulin Li, Houbo Wu, Wenzhou Xiang, Hualian Wu, Na Wang, Jiayi Wu and Tao Li
Foods 2022, 11(14), 2069; https://doi.org/10.3390/foods11142069 - 12 Jul 2022
Cited by 3 | Viewed by 1754
Abstract
Phycoerythrin, a special photosynthetic pigment, is widely used as fluorescent dye and has lots of underlying beneficial effects on health. A marine red microalga Porphyridium is considered as the potential feedstock for phycoerythrin production. However, the phycoerythrin-related properties of Porphyridium have not been [...] Read more.
Phycoerythrin, a special photosynthetic pigment, is widely used as fluorescent dye and has lots of underlying beneficial effects on health. A marine red microalga Porphyridium is considered as the potential feedstock for phycoerythrin production. However, the phycoerythrin-related properties of Porphyridium have not been systematically evaluated, especially between the species of P. cruentum and P. purpureum. The present study aimed to evaluate the production and fluorescence characteristics of phycoerythrin of three strains of Porphyridium. The results showed that P. purpureum SCS-02 presented the highest biomass, phycoerythrin content and yield were 6.43 g L−1, 9.18% DW and 0.288 g L−1, respectively. There was no significant difference between P. purpureum and P. cruentum in α and β subunits amino acid sequences of phycoerythrin and in fluorescence characteristics. The high gene expression level of the key enzymes in phycoerythrobilin synthesis (porphobilinogen synthase and oxygen-dependent coproporphyrinogen-III oxidase) could be related to the high phycoerythrin content of Porphyridium. Based on systematic evaluation, P. purpureum SCS-02 was selected due to its high biomass and phycoerythrin yield. P. purpureum and P. cruentum were highly similar in the phylogenetic tree, as well as in fluorescence characteristics; therefore, it was speculated that they might be the same Porphyridium species. Full article
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26 pages, 1318 KiB  
Article
Optimization of Astaxanthin Recovery in the Downstream Process of Haematococcus pluvialis
by Inga K. Koopmann, Simone Möller, Clemens Elle, Stefan Hindersin, Annemarie Kramer and Antje Labes
Foods 2022, 11(9), 1352; https://doi.org/10.3390/foods11091352 - 06 May 2022
Cited by 7 | Viewed by 3324
Abstract
Astaxanthin derived from Haematococcus pluvialis is a valuable metabolite applied in a wide range of products. Its extraction depends on a sophisticated series of downstream process steps, including harvesting, disruption, drying, and extraction, of which some are dependent on each other. To determine [...] Read more.
Astaxanthin derived from Haematococcus pluvialis is a valuable metabolite applied in a wide range of products. Its extraction depends on a sophisticated series of downstream process steps, including harvesting, disruption, drying, and extraction, of which some are dependent on each other. To determine the processes that yield maximum astaxanthin recovery, bead milling, high-pressure homogenization, and no disruption of H. pluvialis biomass were coupled with spray-drying, vacuum-drying, and freeze-drying in all possible combinations. Eventually, astaxanthin was extracted using supercritical CO2. Optimal conditions for spray-drying were evaluated through the design of experiments and standard least squares regression (feed rate: 5.8 mL/min, spray gas flow: 400 NL/h, inlet temperature: 180 °C). Maximal astaxanthin recoveries were yielded using high-pressure homogenization and lyophilization (85.4%). All combinations of milling or high-pressure homogenization and lyophilization or spray-drying resulted in similar recoveries. Bead milling and spray-drying repeated with a larger spray-dryer resulted in similar astaxanthin recoveries compared with the laboratory scale. Smaller astaxanthin recoveries after the extraction of vacuum-dried biomass were mainly attributed to textural changes. Evaluation of these results in an economic context led to a recommendation for bead milling and spray-drying prior to supercritical CO2 extraction to achieve the maximum astaxanthin recoveries. Full article
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16 pages, 2751 KiB  
Article
Exopolysaccharides from the Energy Microalga Strain Botryococcus braunii: Purification, Characterization, and Antioxidant Activity
by Wei-Nan Wang, Tao Li, Yi Li, Ying Zhang, Hua-Lian Wu, Wen-Zhou Xiang and Ai-Fen Li
Foods 2022, 11(1), 110; https://doi.org/10.3390/foods11010110 - 01 Jan 2022
Cited by 11 | Viewed by 2751
Abstract
Botryococcus braunii, a prestigious energy microalga, has recently received widespread attention because it can secrete large amounts of exopolysaccharides (EPS) with potential applications in food, cosmetics, and nutraceuticals. Unfortunately, the insufficiency of research on the bioactivity and structure–activity relationship of B [...] Read more.
Botryococcus braunii, a prestigious energy microalga, has recently received widespread attention because it can secrete large amounts of exopolysaccharides (EPS) with potential applications in food, cosmetics, and nutraceuticals. Unfortunately, the insufficiency of research on the bioactivity and structure–activity relationship of B. braunii EPS has impeded the downstream applications. In the present study, alcohol precipitation, deproteinization, and DEAE-cellulose column chromatography were used to extract and purify B. braunii SCS-1905 EPS. It was found that B. braunii SCS-1905 EPS were high-molecular-weight heteropolysaccharides containing uronic acid (7.43–8.83%), protein (2.30–4.04%), and sulfate groups (1.52–1.95%). Additionally, the EPS primarily comprised galactose (52.34–54.12%), glucose (34.60–35.53%), arabinose (9.41–10.32%), and minor amounts of fucose (1.80–1.99%), with the presence of a pyranose ring linked by a β-configurational glycosidic bond. Notably, the antioxidant activity of crude exopolysaccharides (CEPS) was stronger, and the half maximal inhibitory concentration (IC50) for ABTS and hydroxyl radicals was significantly lower than that of deproteinized exopolysaccharides (DEPS). Overall, this study indicated a potential application of B. braunii SCS-1905 EPS as a natural antioxidant. In summary, B. braunii EPS could be used as a potential feedstock for the production of antioxidant health foods. Full article
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17 pages, 3872 KiB  
Article
Technological Feasibility of Couscous-Algae-Supplemented Formulae: Process Description, Nutritional Properties and In Vitro Digestibility
by Sheyma Khemiri, Maria Cristiana Nunes, Rui J. B. Bessa, Susana P. Alves, Issam Smaali and Anabela Raymundo
Foods 2021, 10(12), 3159; https://doi.org/10.3390/foods10123159 - 20 Dec 2021
Cited by 12 | Viewed by 3285
Abstract
The aim of this work was to develop functional couscous in a traditional Tunisian manner (hand rolling), enriched in algae biomass (6% w/w). Four Chlorella vulgaris (C. vulgaris) biomasses and one mixture of C. vulgaris and two macroalgae biomasses ( [...] Read more.
The aim of this work was to develop functional couscous in a traditional Tunisian manner (hand rolling), enriched in algae biomass (6% w/w). Four Chlorella vulgaris (C. vulgaris) biomasses and one mixture of C. vulgaris and two macroalgae biomasses (Ulva rigida and Fucus vesiculosus) were used. The C. vulgaris strain was subjected to random mutagenesis and different culture conditions (Allmicroalgae), resulting in different pigmentations and biochemical compositions. Couscous samples were characterized in terms of nutritional properties, oscillatory rheology properties and digestibility. All biomasses provided a significant supplementation of nutrients and excellent acceptance. The enrichment resulted in lower firmness, higher viscoelastic functions (G′ and G″) and a significant improvement in the cooking quality. Major differences between couscous samples with different microalgae were observed in protein and mineral contents, fully meeting Regulation (EC) No. 1924/2006 requirements for health claims made on foodstuffs. The amount of digested proteins was also higher in algae-containing samples. The fatty acid profile of the enriched couscous varied in a biomass-specific way, with a marked increase in linolenic acid (18:3 ω3) and a decrease in the ω6/ω3 ratio. Sensory analysis revealed that microalgae-containing products could compete with conventional goods with an added advantage, that is, having an ameliorated nutritional value using algae as a “trendy” and sustainable ingredient. Full article
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14 pages, 1237 KiB  
Article
Growth and Biochemical Composition Characteristics of Arthrospira platensis Induced by Simultaneous Nitrogen Deficiency and Seawater-Supplemented Medium in an Outdoor Raceway Pond in Winter
by Hualian Wu, Tao Li, Jinting Lv, Zishuo Chen, Jiayi Wu, Na Wang, Houbo Wu and Wenzhou Xiang
Foods 2021, 10(12), 2974; https://doi.org/10.3390/foods10122974 - 03 Dec 2021
Cited by 8 | Viewed by 1938
Abstract
Arthrospira platensis, a well-known cyanobacterium, is widely applied not only in human and animal nutrition but also in cosmetics for its high amounts of active products. The biochemical composition plays a key role in the application performance of the Arthrospira biomass. The [...] Read more.
Arthrospira platensis, a well-known cyanobacterium, is widely applied not only in human and animal nutrition but also in cosmetics for its high amounts of active products. The biochemical composition plays a key role in the application performance of the Arthrospira biomass. The present study aimed to evaluate the growth and biochemical composition characteristics of A. platensis, cultured with a nitrogen-free and seawater-supplemented medium in an outdoor raceway pond in winter. The results showed that the biomass yield could achieve 222.42 g m−2, and the carbohydrate content increased by 247% at the end of the culture period (26 d), compared with that of the starter culture. The daily and annual areal productivities were 3.96 g m−2 d−1 and 14.44 ton ha−1 yr−1 for biomass and 2.88 g m−2 d−1 and 10.53 ton ha−1 yr−1 for carbohydrates, respectively. On the contrary, a profound reduction was observed in protein, lipid, and pigment contents. Glucose, the main monosaccharide in the A. platensis biomass, increased from 77.81% to 93.75% of total monosaccharides. Based on these results, large-scale production of carbohydrate-rich A. platensis biomass was achieved via a low-cost culture, involving simultaneous nitrogen deficiency and supplementary seawater in winter. Full article
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16 pages, 3338 KiB  
Article
A Novel Three-Step Extraction Strategy for High-Value Products from Red Algae Porphyridium purpureum
by Tao Li, Jin Xu, Weinan Wang, Zishuo Chen, Chulin Li, Hualian Wu, Houbo Wu and Wenzhou Xiang
Foods 2021, 10(9), 2164; https://doi.org/10.3390/foods10092164 - 13 Sep 2021
Cited by 10 | Viewed by 2845
Abstract
The microalga Porphyridium accumulates high-value compounds such as phycoerythrin, polyunsaturated fatty acids, and polysaccharides, and thus, the extraction of these compounds could significantly expand the value of Porphyridium biomass. In the present study, a novel fractional extraction strategy based on the characteristics of [...] Read more.
The microalga Porphyridium accumulates high-value compounds such as phycoerythrin, polyunsaturated fatty acids, and polysaccharides, and thus, the extraction of these compounds could significantly expand the value of Porphyridium biomass. In the present study, a novel fractional extraction strategy based on the characteristics of these compounds was established using cold water, 95% ethanol, and hot water. The yield of phycoerythrin, lipids, and polysaccharides was 63.3, 74.3, and 75.2%, respectively. The phycoerythrin exhibited excellent fluorescence characteristics but had low purity. The crude lipid was dark with poor fluidity. Digalactosyldiacylglycerol and sulphoquinovosyldiacylglycerol containing C20:5 and C20:4 were the most abundant glycerolipids, while glucose, xylose, and galactose constituted the intracellular polysaccharides that had covalently bound to proteins (8.01%), uronic acid (4.13%), and sulfate (8.31%). Compared with polysaccharides and crude lipids, crude phycoerythrin showed the best antioxidant activity. Overall, the three-step fractional extraction process was feasible for Porphyridium; however, further purification is necessary for downstream applications. Full article
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14 pages, 2499 KiB  
Article
Study on the Enhancement of Immune Function of Astaxanthin from Haematococcus pluvialis
by Qingsheng Fan, Zhan Chen, Yating Wu, Jiangxin Zhu and Zhou Yu
Foods 2021, 10(8), 1847; https://doi.org/10.3390/foods10081847 - 10 Aug 2021
Cited by 11 | Viewed by 2682
Abstract
This study was aimed at investigating the effect of astaxanthin on the immune function and its safety in mice. It was administered once daily at low, medium and high doses (4.2, 8.35, 16.70 mg/kg BW) to mice for 30 days. Subsequently, the spleen [...] Read more.
This study was aimed at investigating the effect of astaxanthin on the immune function and its safety in mice. It was administered once daily at low, medium and high doses (4.2, 8.35, 16.70 mg/kg BW) to mice for 30 days. Subsequently, the spleen and thymus index, spleen lymphocyte transformation activity, delayed allergy reaction, amounts of antibody-producing cells, half-hemolytic value HC50, carbon particle clearance rate, macrophage phagocytosis, and natural killer cell (NK) activity were determined. Acute oral toxicity and genotoxicity tests were conducted to evaluate the safety of astaxanthin. Compared with the control group, medium and high doses of astaxanthin significantly increased the proliferation and transformation activities of spleen lymphocytes, activities of antibody-producing cells, serum hemolysin levels, and carbon particle clearance rate in mice (phagocytic index). High doses significantly improved delayed allergy reaction and NK cell activity. Results of acute oral toxicity and genotoxicity tests were negative. Gross anatomical observations and histopathological examination showed no abnormal changes associated with the treatments. In the article, it is confirmed that astaxanthin treatments significantly improve immune functions and show no toxic effects in the experimental doses. Full article
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11 pages, 2212 KiB  
Article
Effect of Light Intensity and Wavelength on Biomass Growth and Protein and Amino Acid Composition of Dunaliella salina
by Yixing Sui and Patricia J. Harvey
Foods 2021, 10(5), 1018; https://doi.org/10.3390/foods10051018 - 07 May 2021
Cited by 21 | Viewed by 3672
Abstract
Dunaliella salina is a halotolerant, photoautotrophic marine microalga and one of the richest sources of natural carotenoids but also shows potential as a novel food source with high protein quality. This study sought to optimise the production of biomass, protein and amino acids [...] Read more.
Dunaliella salina is a halotolerant, photoautotrophic marine microalga and one of the richest sources of natural carotenoids but also shows potential as a novel food source with high protein quality. This study sought to optimise the production of biomass, protein and amino acids from D. salina, alongside carotenoids using a two-stage cultivation approach based on the use of light of different intensities and quality, i.e., white, red and blue LED light. In stage 1, four white LED light intensities were tested. In stage 2, the same four light intensities from either blue or red LEDs were applied once exponential growth ceased and cells reached the stationary phase under white LED light in stage 1. Remarkably, both biomass concentration and biomass productivity showed a 1.3–1.7-fold increase in stage 2, without medium replenishment, while protein concentration and protein productivity showed an ~1.1-fold increase. The amino acid content and amino acid index remained unchanged from stage 1 to stage 2, and minimum difference was found across different light intensities. Overall, D. salina delivered so-called high protein quality, with an essential amino acid index (EAAI) of 0.99, and red light, which has previously been shown to increase carotenoid production, boosted further biomass production over and above white light, at all light intensities tested. Full article
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Review

Jump to: Research

17 pages, 314 KiB  
Review
Research Progresses on the Physiological and Pharmacological Benefits of Microalgae-Derived Biomolecules
by Zhou Yu, Yan Hong, Kun Xie and Qingsheng Fan
Foods 2022, 11(18), 2806; https://doi.org/10.3390/foods11182806 - 11 Sep 2022
Cited by 4 | Viewed by 1856
Abstract
Microalgae are a kind of photoautotrophic microorganism, which are small, fast in their growth rate, and widely distributed in seawater and freshwater. They have strong adaptability to diverse environmental conditions and contain various nutrients. Many scholars have suggested that microalgae can be considered [...] Read more.
Microalgae are a kind of photoautotrophic microorganism, which are small, fast in their growth rate, and widely distributed in seawater and freshwater. They have strong adaptability to diverse environmental conditions and contain various nutrients. Many scholars have suggested that microalgae can be considered as a new food source, which should be developed extensively. More importantly, in addition to containing nutrients, microalgae are able to produce a great number of active compounds such as long-chain unsaturated fatty acids, pigments, alkaloids, astaxanthin, fucoidan, etc. Many of these compounds have been proven to possess very important physiological functions such as anti-oxidation, anti-inflammation, anti-tumor functions, regulation of the metabolism, etc. This article aimed to review the physiological functions and benefits of the main microalgae-derived bioactive molecules with their physiological effects. Full article
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32 pages, 774 KiB  
Review
Health Benefits, Food Applications, and Sustainability of Microalgae-Derived N-3 PUFA
by Yanjun Liu, Xiang Ren, Chao Fan, Wenzhong Wu, Wei Zhang and Yanwen Wang
Foods 2022, 11(13), 1883; https://doi.org/10.3390/foods11131883 - 25 Jun 2022
Cited by 22 | Viewed by 5612
Abstract
Today’s consumers are increasingly aware of the beneficial effects of n-3 PUFA in preventing, delaying, and intervening various diseases, such as coronary artery disease, hypertension, diabetes, inflammatory and autoimmune disorders, neurodegenerative diseases, depression, and many other ailments. The role of n-3 PUFA on [...] Read more.
Today’s consumers are increasingly aware of the beneficial effects of n-3 PUFA in preventing, delaying, and intervening various diseases, such as coronary artery disease, hypertension, diabetes, inflammatory and autoimmune disorders, neurodegenerative diseases, depression, and many other ailments. The role of n-3 PUFA on aging and cognitive function is also one of the hot topics in basic research, product development, and clinical applications. For decades, n-3 PUFA, especially EPA and DHA, have been supplied by fish oil and seafood. With the continuous increase of global population, awareness about the health benefits of n-3 PUFA, and socioeconomic improvement worldwide, the supply chain is facing increasing challenges of insufficient production. In this regard, microalgae have been well considered as promising sources of n-3 PUFA oil to mitigate the supply shortages. The use of microalgae to produce n-3 PUFA-rich oils has been explored for over two decades and some species have already been used commercially to produce n-3 PUFA, in particular EPA- and/or DHA-rich oils. In addition to n-3 PUFA, microalgae biomass contains many other high value biomolecules, which can be used in food, dietary supplement, pharmaceutical ingredient, and feedstock. The present review covers the health benefits of n-3 PUFA, EPA, and DHA, with particular attention given to the various approaches attempted in the nutritional interventions using EPA and DHA alone or combined with other nutrients and bioactive compounds towards improved health conditions in people with mild cognitive impairment and Alzheimer’s disease. It also covers the applications of microalgae n-3 PUFA in food and dietary supplement sectors and the economic and environmental sustainability of using microalgae as a platform for n-3 PUFA-rich oil production. Full article
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33 pages, 1450 KiB  
Review
Production, Processing, and Protection of Microalgal n-3 PUFA-Rich Oil
by Xiang Ren, Yanjun Liu, Chao Fan, Hao Hong, Wenzhong Wu, Wei Zhang and Yanwen Wang
Foods 2022, 11(9), 1215; https://doi.org/10.3390/foods11091215 - 22 Apr 2022
Cited by 13 | Viewed by 2707
Abstract
Microalgae have been increasingly considered as a sustainable “biofactory” with huge potentials to fill up the current and future shortages of food and nutrition. They have become an economically and technologically viable solution to produce a great diversity of high-value bioactive compounds, including [...] Read more.
Microalgae have been increasingly considered as a sustainable “biofactory” with huge potentials to fill up the current and future shortages of food and nutrition. They have become an economically and technologically viable solution to produce a great diversity of high-value bioactive compounds, including n-3 polyunsaturated fatty acids (PUFA). The n-3 PUFA, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), possess an array of biological activities and positively affect a number of diseases, including cardiovascular and neurodegenerative disorders. As such, the global market of n-3 PUFA has been increasing at a fast pace in the past two decades. Nowadays, the supply of n-3 PUFA is facing serious challenges as a result of global warming and maximal/over marine fisheries catches. Although increasing rapidly in recent years, aquaculture as an alternative source of n-3 PUFA appears insufficient to meet the fast increase in consumption and market demand. Therefore, the cultivation of microalgae stands out as a potential solution to meet the shortages of the n-3 PUFA market and provides unique fatty acids for the special groups of the population. This review focuses on the biosynthesis pathways and recombinant engineering approaches that can be used to enhance the production of n-3 PUFA, the impact of environmental conditions in heterotrophic cultivation on n-3 PUFA production, and the technologies that have been applied in the food industry to extract and purify oil in microalgae and protect n-3 PUFA from oxidation. Full article
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19 pages, 1206 KiB  
Review
The Extraction of β-Carotene from Microalgae for Testing Their Health Benefits
by Jing Wang, Xinge Hu, Junbin Chen, Tiannan Wang, Xianju Huang and Guoxun Chen
Foods 2022, 11(4), 502; https://doi.org/10.3390/foods11040502 - 10 Feb 2022
Cited by 25 | Viewed by 5714
Abstract
β-carotene, a member of the carotenoid family, is a provitamin A, and can be converted into vitamin A (retinol), which plays essential roles in the regulation of physiological functions in animal bodies. Microalgae synthesize a variety of carotenoids including β-carotene and are a [...] Read more.
β-carotene, a member of the carotenoid family, is a provitamin A, and can be converted into vitamin A (retinol), which plays essential roles in the regulation of physiological functions in animal bodies. Microalgae synthesize a variety of carotenoids including β-carotene and are a rich source of natural β-carotene. This has attracted the attention of researchers in academia and the biotech industry. Methods to enrich or purify β-carotene from microalgae have been investigated, and experiments to understand the biological functions of microalgae products containing β-carotene have been conducted. To better understand the use of microalgae to produce β-carotene and other carotenoids, we have searched PubMed in August 2021 for the recent studies that are focused on microalgae carotenoid content, the extraction methods to produce β-carotene from microalgae, and the bioactivities of β-carotene from microalgae. Articles published in peer-reviewed scientific journals were identified, screened, and summarized here. So far, various types and amounts of carotenoids have been identified and extracted in different types of microalgae. Diverse methods have been developed overtime to extract β-carotene efficiently and practically from microalgae for mass production. It appears that methods have been developed to simplify the steps and extract β-carotene directly and efficiently. Multiple studies have shown that extracts or whole organism of microalgae containing β-carotene have activities to promote lifespan in lab animals and reduce oxidative stress in culture cells, etc. Nevertheless, more studies are warranted to study the health benefits and functional mechanisms of β-carotene in these microalgae extracts, which may benefit human and animal health in the future. Full article
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18 pages, 661 KiB  
Review
Microalgae as Sources of High-Quality Protein for Human Food and Protein Supplements
by Yanwen Wang, Sean M. Tibbetts and Patrick J. McGinn
Foods 2021, 10(12), 3002; https://doi.org/10.3390/foods10123002 - 04 Dec 2021
Cited by 91 | Viewed by 8738
Abstract
As a result of population growth, an emerging middle-class, and a more health-conscious society concerned with overconsumption of fats and carbohydrates, dietary protein intake is on the rise. To address this rapid change in the food market, and the subsequent high demand for [...] Read more.
As a result of population growth, an emerging middle-class, and a more health-conscious society concerned with overconsumption of fats and carbohydrates, dietary protein intake is on the rise. To address this rapid change in the food market, and the subsequent high demand for protein products, agriculture, aquaculture, and the food industry have been working actively in recent years to increase protein product output from both production and processing aspects. Dietary proteins derived from animal sources are of the highest quality, containing well-balanced profiles of essential amino acids that generally exceed those of other food sources. However, as a result of studies highlighting low production efficiency (e.g., feed to food conversion) and significant environmental impacts, together with the negative health impacts associated with the dietary intake of some animal products, especially red meats, the consumption of animal proteins has been remaining steady or even declining over the past few decades. To fill this gap, researchers and product development specialists at all levels have been working closely to discover new sources of protein, such as plant-based ingredients. In this regard, microalgae have been recognized as strategic crops, which, due to their vast biological diversity, have distinctive phenotypic traits and interactions with the environment in the production of biomass and protein, offering possibilities of production of large quantities of microalgal protein through manipulating growing systems and conditions and bioengineering technologies. Despite this, microalgae remain underexploited crops and research into their nutritional values and health benefits is in its infancy. In fact, only a small handful of microalgal species are being produced at a commercial scale for use as human food or protein supplements. This review is intended to provide an overview on microalgal protein content, its impact by environmental factors, its protein quality, and its associated evaluation methods. We also attempt to present the current challenges and future research directions, with a hope to enhance the research, product development, and commercialization, and ultimately meet the rapidly increasing market demand for high-quality protein products. Full article
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