Appl. Biosci., Volume 2, Issue 1 (March 2023) – 10 articles

The transfer of atmospheric carbon (C) in soils is a possible strategy for climate change mitigation and for restoring land productivity. While some studies have compared the ability of existing crops to allocate C into the soil, the genetic variations between crop genotypes have received less attention. The objective of this study was to compare the allocation to the soil of atmospheric C by genetically diverse wheat genotypes under different scenarios of soil water availability. The experiments were set up under open-field and greenhouse conditions with 100 wheat genotypes sourced from the International Maize and Wheat Improvement Centre and grown at 25% (drought stressed) and 75% (non-stressed) field capacity, using an alpha lattice design with 10 incomplete blocks and 10 genotypes per block. The genotypes were analyzed for grain yield (GY), plant shoot and root biomass (SB and RB, respectively) and C content, and stocks in plant parts. Additionally, ¹³C pulse labeling was performed during the crop growth period of 10 selected genotypes for assessing soil C inputs. The average GY varied from 75 to 4696 g m⁻² and total plant biomass (PB) from 1967 to 13,528 g m⁻². The plant C stocks ranged from 592 to 1109 g C m⁻² (i.e., an 87% difference) under drought condition and between 1324 and 2881 g C m⁻² (i.e., 117%) under well-watered conditions. Atmospheric C transfer to the soil only occurred under well-drained conditions and increased with the increase in the root to shoot ratio for C stocks (r = 0.71). Interestingly, the highest transfer to the soil was found for LM-26 and LM-47 (¹³C/¹²C of 7.6 and 6.5 per mille, respectively) as compared to LM-70 and BW-162 (0.75; 0.85). More is to be done to estimate the differences in C fluxes to the soil over entire growing seasons and to assess the long-term stabilization of the newly allocated C. Future research studies also need to identify genomic regions associated with GY and soil C transfer to enable the breeding of “carbon-superior” cultivars. Full article

Multifunctional materials and devices with captivating properties can be assembled from cellulose and cellulose-based composite materials combining functionality with structural performance. Cellulose is one of the most abundant renewable materials with captivating properties, such as mechanical robustness, biocompatibility, and biodegradability. Cellulose is a low-cost and abundant biodegradable resource, CO₂ neutral, with a wide variety of fibers available all over the world. Over thousands of years, nature has perfected cellulose-based materials according to their needs, such as function vs. structure. Mimicking molecular structures at the nano-, micro-, and macroscales existing in nature is a great strategy to produce synthetic cellulose-based active materials. A concise background of cellulose and its structural organization, as well as the nomenclature of cellulose nanomaterials, are first addressed. Key examples of nature-designed materials with unique characteristics, such as “eternal” coloration and water-induced movement are presented. The production of biomimetic fiber and 2D fiber-based cellulosic materials that have attracted significant attention within the scientific community are represented. Nature-inspired materials with a focus on functionality and response to an external stimulus are reported. Some examples of 3D-printed cellulosic materials bioinspired, reported recently in the literature, are addressed. Finally, printed cellulosic materials that morph from a 1D strand or 2D surface into a 3D shape, in response to an external stimulus, are reported. The purpose of this review is to discuss the most recent developments in the field of “nature-inspired” cellulose-based active materials regarding design, manufacturing, and inspirational sources that feature existing tendencies. Full article

Chicory (Cichorium intybus L.) is a low-height perennial or biennial herb from the family of Asteraceae. Investigation of different in vitro regeneration strategies of Cichorium intybus and increasing the number of secondary metabolites in vitro regenerated plant samples were the aims of the research. Callus and plant regenerations were achieved in basal plant growth media supplemented with plant growth regulators (PGRs). Whole plant regeneration was carried out by direct organogenesis from leaf explant in Murashige and Skoog (MS) and B5 media supplemented with naphthalene acetic (NAA) acid and indole-3-butyric acid (IBA). The highest callus quantity was produced in MS medium supplemented with indole-3-acetic acid (IAA) and benzyl amino purine (BAP). The combination and concentrations of PGRs used in MS and B5 media not only provided root and shoot formation with callus, but also caused a change in the amounts of phenolic components. In addition, some PGRs used caused an increase in the number of phenolic compounds in callus and shoots developed from the leaf explant. When plants that grow in vitro and in vivo are compared with each other, it has been determined that plants grown in vivo contain higher amounts of some phenolic compounds. In vivo and in vitro samples were extracted in ethanol/water (80:20 v/v). The analysis of phenolic compounds (caftaric, chicoric, and chlorogenic acids and esculin) were performed in high-performance liquid chromatography (HPLC) and inulin was in UV spectrophotometry. The caftaric and chlorogenic acids and inulin concentrations were higher in vivo samples than that in vitro. Contrarily, esculin, and chicoric acid concentrations were higher in the in vitro regenerated samples. The higher concentration of valuable compounds in the in vitro regenerated samples, especially in callus tissue, gives hope for large-scale production of secondary metabolites under laboratory conditions. Full article

As an effective soil amendment, biochars require a comprehensive ecological evaluation before they can be widely used in agriculture because endogenous contaminants, such as environmentally persistent free radicals (EPFRs), certainly pose an ecological risk to soil invertebrates. In this study, Caenorhabditis elegans (C. elegans) was used as a model organism to investigate the neurotoxicity of two rice straw biochars pyrolyzed at 500 and 700 °C. After 24 h exposure to unwashed biochar, washed biochar, and leaching fluids (supernatants), the neurobehavioral parameters of C. elegans were determined in a liquid toxicity test. The results showed that the washed 700 °C biochar particles significantly impaired locomotion and prolonged the defecation interval at a biochar concentration of 4 g·well⁻¹, while the unwashed biochar and supernatants caused no apparent impairment. Supporting this, electron paramagnetic resonance (EPR) results showed that the intensity of EPFRs in unwashed 700 °C biochar was stronger than that of the corresponding washed particles. This indicates that, in the liquid test, the EPR signal alone is not indicative of particle toxicity. The accessibility and activity of the EPFRs should be considered. Dissolved organic matter (DOM) was observed in the leaching fluids. The neurotoxic activity of the washed biochar was alleviated after the re-addition of leaching fluids to the washed biochar, suggesting that the dissolved organic materials modulate the reactivity of the EPFRs in the liquid phase. This study suggests that the leaching process may increase the risk of biochar when used in the field environment. Full article

Scientists have long sought a technology to humanely control populations of damaging invasive pests in a species-specific manner. Gene drive technology could see this become a reality. This review charts the twists and turns on the road to developing gene drives in vertebrates. We focus on rodents, as these will likely be the first targets, and trace the journey from the early understanding of selfish genetic elements to engineering gene drives in mice; before discussing future research focuses and the crucial role that public perception and governance will play in the application of this technology. The realisation of robust gene drive strategies in vertebrate pests has the potential to revolutionise biocontrol. Full article

The literature on the crosstalk between the brain and the gut has increased considerably in recent years. It is widely accepted now that the microbiome plays a significant role in several brain disorders, neurodevelopment, neurocognitive stages, and physiological functions. However, the mechanisms that influence such crosstalk are still not well elucidated. In this sense, one of the possible mechanisms by which the microbiome could influence brain function is through gut hormones released by enteroendocrine cells: ghrelin, cholecystokinin (CCK), peptide YY (PYY), vasoactive intestinal polypeptide (VIP), glucagon-like peptide (GLP1-2), corticotropin-releasing factor (CRF), glucose-dependent insulinotropic polypeptide (GIP), secretin, serotonin (5-HT), and oxytocin. Especially when one considers that the brain expresses receptors for these hormones in areas important to the neurobiology of brain disorders (e.g., depression), such as the hippocampus, amygdala, hypothalamus, and suprachiasmatic nucleus. To strengthen this hypothesis, gastrointestinal dysfunction (such as altered motility or pain) is relatively common in depressive patients, and changes in diet (low-carbohydrate diets, for example) positively affect mood. Additionally, alterations in the gut microbiome are relatively common in depressive patients and are related to the levels of Akkermansia, Lactobacillus, Bifidobacteria, Faecalibacterium, Roseburia and Clostridium. Finally, concerning the gut-released hormones, the literature reports that ghrelin can be a peripheral marker for the antidepressant treatment success rate and has elevated levels during depression. GLP-1 is tightly correlated with HPA axis activity being decreased by high cortisol levels. CCK seems to be altered in depression due to increased inflammation and activation of Toll-like receptor 4. Such finds allow the postulation that hormones, the microbiome and mood are intertwined and co-dependent. VIP is correlated with circadian rhythms. There is a bidirectional connection of the circadian rhythms between the host and the microbiota. Circadian rhythm disruption is associated with both poor outcomes in mental health and alterations in the microbiota composition. In sum, in the past year, more and more research has been published showing the tight connection between gut and brain health and trying to decipher the feedback in play. Here, we focus on depression. Full article

Microbiologically influenced corrosion (MIC) of metal alloys is promoted by biofilms formed on metal surfaces. In the marine environment, MIC causes serious metal infrastructure problems, which lead to significant economic losses. In this study, we used an enrichment culture approach to examine the bacterial community that grows on metal surface at levels below the detection limit as a preliminary study for developing guidelines to prevent biofilm formation. An enrichment culture approach was employed to analyze the bacterial community on metal surface without biofilms and corrosion. Genomic DNA was extracted from culture sample after incubation in the enrichment culture with a metal piece, and then the V3–V4 variable regions of the bacterial 16S rRNA gene were amplified using the extracted genomic DNA as the template. Subsequently, using a next-generation sequencing approach, the amplified V3–V4 regions were sequenced, and the bacterial community was analyzed using the QIIME 2 microbiome bioinformatics platform. Using this enrichment culture approach, more than 80 bacterial genera were detected with Sphingomonas bacteria exhibiting the highest relative abundance (44%). These results demonstrated that this method could be useful for bacterial community analysis for bacteria below detection limits, and will serve as a basis for the development of the guidelines. Full article

Microalgae are a source of carbohydrates, proteins and lipids. Thus, they can be considered as raw material to transition from current fossil fuel-based refineries to biorefineries. Microalgae harvesting is considered a major challenge in biomass production. There are several harvesting techniques, but the majority of them are either expensive or not effective. The harvesting method that we propose is sedimentation-induced by light blockage, taking advantage of the motility characteristics of certain microalgae. In this research, the halophilic microalgae Dunaliella salina was selected. Experiments were conducted under light and dark conditions to compare the sedimentation rates. Sedimentation behavior was measured by collecting data on the optical density and cell count under both light and dark conditions. The results showed that, under light conditions, the cell count in the middle of the flask decreased from 1 × 10⁶ cell/mL to 5 × 10⁴ cell/mL after 50 days. Under dark conditions sedimentation took less than 10 days for complete settlement. Leaving Dunaliella salina under dark conditions may constitute a promising harvest method as this provides a high recovery rate and requires low energy. Full article

The ability of Aspergillus niger strains to support citric acid production using solid-state fermentation of agricultural processing coproducts was examined in this review. Citric acid has been shown to have a number of commercial applications in the food and beverage industries. The A. niger strains capable of elevated citric acid production are known to contain genetic mutations that stimulate overproduction of the organic acid likely involving citric acid cycle reactions. The agricultural processing coproducts previously examined for their ability to support citric acid production by A. niger solid-state fermentation include fruit processing wastes, sugarcane bagasse, starch vegetable processing wastes and cereal grain processing coproducts. A comparison of citric acid production by A. niger strains using solid-state fermentation demonstrated that certain agricultural processing coproducts were more effective in supporting a high level of acid synthesis. In particular, fruit processing wastes, such as apple pomace, banana peels, grape pomace and orange peels, supported high levels of citric acid by the fungal strains following solid-state fermentation. On the other hand, processing coproducts of cereal grains, such as brans and ethanol processing coproducts, supported low levels of citric acid production by the A. niger strains using solid-state fermentation. It appeared that the cereal processing coproducts provided less available sugar content to support citric acid production by the fungal strains. It was concluded that the level of citric acid produced by the A. niger strains during solid-state fermentation was dependent on the sugar content of the agricultural processing coproduct utilized. Full article