Biomass Concentration Research Articles

Dung Beetles, Dung Burial, and Plant Growth: Four Scarabaeoid Species and Sorghum

This study examined the impact of dung beetles on both sorghum growth and the physico-chemical properties of the soil over a two-month period. Four dung beetle species (Onthophagus vacca, Onthophagus marginalis subsp. andalusicus, Euonthophagus crocatus, and Gymnopleurus sturmi) were introduced into experimental setups, consisting of containers filled with sterilised clay-loam soil, with three treatment groups: [cow dung + beetles], [cow dung only], and a control group (no dung nor beetles), in order to evaluate their effects on various growth parameters, including the plant height, biomass, leaf area, and chlorophyll concentration. Additionally, changes in soil properties were assessed, focusing on the organic matter content, pH, conductivity, enzyme activities (e.g., urease, phosphatase), and microbial load. The results revealed significant increases in all the measured parameters across the treatments involving dung beetles, emphasising their role in enhancing soil fertility and plant productivity. The study also highlights the variation in effectiveness among the species, suggesting that beetle diversity plays a crucial role in nutrient cycling. Integrating dung beetles into sustainable farming practices could, therefore, serve as a key strategy to promote resilient agriculture.

Changes in Photosynthetic Efficiency, Biomass, and Sugar Content of Sweet Sorghum Under Different Water and Salt Conditions in Arid Region of Northwest China

Sweet sorghum (Sorghum bicolor L. Moench) has significant cultivation potential in arid and saline–alkaline regions due to its drought and salt tolerance. This study aims to evaluate the mechanisms by which increased soil salinity and reduced irrigation affect the growth, aboveground biomass, and stem sugar content of sweet sorghum. A two-year field experiment was conducted, with four salinity levels (CK: 4.17 dS/m, S1: 5.83 dS/m, S2: 7.50 dS/m, and S3: 9.17 dS/m) and three irrigation levels (W1: 90 mm, W2: 70 mm, and W3: 50 mm). The results showed that increased salinity and reduced irrigation significantly reduced both the emergence rate and aboveground biomass, with the decreases in the emergence rate ranging from 11.0% to 36.2% and the reductions in the aboveground biomass ranging from 15.9% to 43.8%. Additionally, increased soil salinity led to reductions in stem sugar content of 6.3% (S1), 8.8% (S2), and 12.8% (S3), respectively. The results also indicated that photosynthetic efficiency, including the net photosynthetic rate (Pn), stomatal conductance (Gs), and chlorophyll content (SPAD), was significantly hindered under increased water and salt stress, with the Pn decreasing by up to 50.4% and the SPAD values decreasing by up to 36.3% under the highest stress conditions. These findings underscore the adverse impacts of increased soil salinity and reduced irrigation on sweet sorghum’s growth, photosynthetic performance, and sugar accumulation, offering critical insights for optimizing its cultivation in arid and saline environments.

Changes in Growth and Metabolic Profile of Scutellaria baicalensis Georgi in Response to Sodium Chloride

Scutellaria baicalensis Georgi is a valuable medicinal plant of the Lamiaceae family. Its roots have been used in Traditional Chinese Medicine (under the name Huang-qin) since antiquity and are nowadays included in Chinese and European Pharmacopoeias. It is abundant in bioactive compounds which constitute up to 20% of dried root mass. These substances are lipophilic flavones with unsubstituted B-ring, baicalein, and wogonin and their respective glucuronides–baicalin and wogonoside being the most abundant. The content of these compounds is variable and the environmental factors causing this remain partially unknown. The role of these compounds in stress response is still being investigated and in our efforts to measure the effect of NaCl treatment on S. baicalensis growth and metabolic profile, we hope to contribute to this research. Short-term exposure to salt stress (50, 100, and 150 mM NaCl) resulted in a marked increase in baicalein from 1.55 mg to 2.55 mg/g DM, (1.6-fold) baicalin from 8.2 mg to 14.7 mg (1.8-fold), wogonin from 4.9 to 6.8 (1.4-fold), and wogonoside from 3.3 to 6.8 mg/g DM (2-fold) concentrations in the roots. Conversely, in aerial parts, the content of individual major flavonoids carthamidine-7-O-glucuronide and scutellarein-7-O-glucuronide decreased the most by 10–50% from 18.6 mg to 11.3 mg/g (1.6-fold less) and from 6.5 mg to 3.4 mg/ g DM (0.52-fold less), respectively. The amino acid profile was also altered with an increase in root concentrations of the following amino acids: arginine from 0.19 to 0.33 mg/g (1.7-fold), glutamate from 0.09 to 0.16 mg/g DM (1.6-fold), alanine from 0.009 to 0.06 mg/g (6.8-fold), proline from 0.011 to 0.029 (2.4-fold) and lysine from 0.016 to 0.063 mg/g (3.9-fold). Aspartate concentration decreased from 0.01 to 0.002 mg/g (4.8-fold less) at 150 mM NaCl. In the aerial parts, the concentration and variation in levels of specific amino acids differed among groups. For instance, the glutamate content exhibited a significant increase exclusively in the treatment group, rising from 0.031 to 0.034 mg/g, representing a 1.2-fold increase. Proline concentration showed a marked increase across all treated groups with the highest from 0.011 to 0.11 mg/g (10-fold). In conclusion, moderate salt stress was shown to increase S. baicalensis root biomass and flavonoid content which is rarely observed in a glycophyte species and provides a foundation for further studies on the mechanisms of osmotic stress adaptation on the specialized metabolism level.

Phytoremediation Potential of Melia azedarach and Ailanthus altissima for Pb, Zn, and Cu from Aqueous Solution

Growing concerns over metal pollution highlight the need for effective remediation strategies. This study evaluates the accumulation capacity and tolerance of Melia azedarach and Ailanthus altissima for trace elements (Pb, Zn, and Cu), aiming to assess their phytoremediation potential. Three-month-old seedlings of both species, grown from seeds collected at the Touissit mine site, were cultivated in perlite and irrigated with Hoagland nutrient solution. Plants were exposed to various concentrations of metal salts—Pb(NO3)2 (8, 40, and 80 mg.L−1), ZnSO4 (8, 40, and 80 mg.L−1), and CuSO4 (2, 10, and 20 mg.L−1)—over a 90-day period. Growth, biomass, metal accumulation, chlorophyll, and carotenoid contents were measured. Results indicate that M. azedarach exhibited enhanced biomass under Pb exposure, suggesting notable tolerance and potential for phytoremediation. Conversely, A. altissima showed an initial increase in biomass at low Pb levels, followed by a significant reduction at higher concentrations. Both species demonstrated decreased biomass under Zn and Cu treatments, with varying degrees of sensitivity. Notably, A. altissima accumulated significant levels of Pb, Zn, and Cu, particularly in the roots, indicating high phytoremediation potential. While M. azedarach also accumulated metals, levels were comparatively lower. Both species maintained chlorophyll content under metal stress, indicating resilience. Overall, this hydroponic screening highlights the considerable capacities of M. azedarach and A. altissima for Pb, Zn, and Cu tolerance, with A. altissima showing particularly high potential for Pb phytostabilization.

Biosorption, Recovery and Reuse of Cu(II) by Penicillium sp. 8L2: A Proposal Framed Within Environmental Regeneration and the Sustainability of Mineral Resources

The copper contamination of terrestrial and aquatic ecosystems is a major global environmental problem. Copper is a metal used in many industrial and agricultural processes that is bioaccumulative and highly toxic, making its elimination, recovery and reuse of great interest for environmental sustainability. At the same time, the use of ubiquitous microorganisms is presented as a crucial tool in the field of the sustainability of mineral resources, which in many cases end up as bioaccumulative pollutants, since they can allow the recovery of metallic ions present in low concentrations and, in parallel, the reconversion of these into crystalline species that can be used in other technological fields. The potential of a ubiquitous microorganism, Penicillium sp. 8L2, to retain Cu(II) ions was investigated, as well as the ability of its cellular extract to synthesize CuO nanoparticles, which were subsequently evaluated as biocidal agents against five microorganisms. A response surface methodology was used to determine the optimal operating conditions of the biosorption process, setting the pH at 4.8 and the biomass concentration at 0.8 g/L and obtaining a maximum biosorption capacity at equilibrium of 25.79 mg/g for the Langmuir model. Different analytical techniques were used to study the biosorption mechanisms, which revealed the presence of surface adsorption and intracellular bioaccumulation phenomena involving different functional groups. The fungal cell extract allowed the successful synthesis of CuO-NPs with an average size of 22 nm. The biocidal tests performed with the nanoparticles showed promising values of minimum inhibitory concentrations between 62.5 and 500 µg/mL. Penicillium sp. 8L2 showed good potential for its application in the field of heavy metal bioremediation and for the green synthesis of nanoparticles useful in biomedicine.

Metabolomics profiles of the liquid co-culture of Sanghuangporus vaninii and Pleurotus sapidus

IntroductionFungal secondary metabolites (SMs) have broad application prospects in the food and medicine industries. Co-culturing strategies that simulate natural symbiotic relationships among microorganisms are used to discover and enhance the production of new SMs. We aimed to use the abundant resources of large edible and medicinal fungi to enhance the yield of desired metabolites through co-culture and potentially produce metabolites that cannot be generated in pure cultures.MethodsWe assessed the biomass and intracellular polysaccharide (IPS) content of liquid co-cultures of Sanghuangporus vaninii and Pleurotus sapidus. Subsequently, the effect of the liquid co-culture on fungal intracellular metabolites was studied using UPLC-QTOF.ResultsCo-culturing of S. vaninii with P. sapidus resulted in significantly increased biomass and IPS content; however, P. sapidus had a significant inhibitory effect on the growth of S. vaninii. Metabolomic data further indicated that amino acid, nucleotide, and glycerophospholipid metabolisms were the primary metabolic pathways affected by symbiosis.DiscussionThis study provides insights into fungal interactions and cellular metabolic mechanisms, contributing to the understanding and enhancement of the fungal fermentation potential.

Asphaltenes biodegradation from heavy crude oils by the yeast Yarrowia lipolytica.

Heavy crude oil reserves are characterized by their high viscosity and density, largely due to significant quantities of asphaltenes. The removal of asphaltene precipitates from oil industry installations is crucial, as they can contaminate catalysts and obstruct pipelines. Therefore, this study aimed to bio-transform heavy oil asphaltenes into smaller molecules using the yeast Yarrowia lipolytica, known for its ability to efficiently degrade hydrophobic substrates. For this purpose, asphaltenes were extracted from crude oil samples, and yeast growth was assessed in a mineral medium containing 2, 5, or 10g L-1 of asphaltenes. After 168h of incubation, liquid-liquid extraction was conducted on samples from the Yarrowia lipolytica growth medium using chloroform. The extracted fractions were then quantified by gas chromatography. The results indicated that the yeast could utilize the asphaltenes as a carbon source for growth, though there was a delay in growth compared to the control (glucose as the carbon source), with a maximum biomass concentration of 2.26g L-1 achieved at 144h. From the experimental design, it was determined that a higher concentration of aromatic compounds was achieved under the conditions of 115rpm, 2g L-1 of asphaltenes, and 0.5g L-1 of cell inoculum. Conversely, to obtain a higher concentration of saturated compounds, the optimal conditions were 160rpm, 5g L-1 of asphaltenes, and 1.0g L-1 of cell inoculum. Molecular docking results indicated that asphaltenes have a high affinity for cytochrome P450, laccase, and Lip2, with interactions observed with their catalytic triads, suggesting a significant role for these enzymes in asphaltene bioconversion.

Quantitative physiology and biomass composition of Cyberlindnera jadinii in ethanol-grown cultures

BackgroundElimination of greenhouse gas emissions in industrial biotechnology requires replacement of carbohydrates by alternative carbon substrates, produced from CO2 and waste streams. Ethanol is already industrially produced from agricultural residues and waste gas and is miscible with water, self-sterilizing and energy-dense. The yeast C. jadinii can grow on ethanol and has a history in the production of single-cell protein (SCP) for feed and food applications. To address a knowledge gap in quantitative physiology of C. jadinii during growth on ethanol, this study investigates growth kinetics, growth energetics, nutritional requirements, and biomass composition of C. jadinii strains in batch, chemostat and fed-batch cultures.ResultsIn aerobic, ethanol-limited chemostat cultures, C. jadinii CBS 621 exhibited a maximum biomass yield on ethanol (YX/Smax) of 0.83 gbiomass (gethanol)−1 and an estimated maintenance requirement for ATP (mATP) of 2.7 mmolATP (gbiomass)−1 h−1. Even at specific growth rates below 0.05 h−1, a stable protein content of approximately 0.54 gprotein (gbiomass)−1 was observed. At low specific growth rates, up to 17% of the proteome consisted of alcohol dehydrogenase proteins, followed by aldehyde dehydrogenases and acetyl-CoA synthetase. Of 13 C. jadinii strains evaluated, 11 displayed fast growth on ethanol (μmax > 0.4 h−1) in mineral medium without vitamins, and CBS 621 was found to be a thiamine auxotroph. The prototrophic strain C. jadinii CBS 5947 was grown on an inorganic salts medium in fed-batch cultures (10-L scale) fed with pure ethanol. Biomass concentrations in these cultures increased up to 100 gbiomass (kgbroth)−1, with a biomass yield of 0.65 gbiomass (gethanol)−1. Model-based simulation, based on quantitative parameters determined in chemostat cultures, adequately predicted biomass production. A different protein content of chemostat- and fed-batch-grown biomass (54 and 42%, respectively) may reflect the more dynamic conditions in fed-batch cultures.ConclusionsAnalysis of ethanol-grown batch, chemostat and fed-batch cultures provided a quantitative physiology baseline for fundamental and applied research on C. jadinii. Its high maximum growth rate, high energetic efficiency of ethanol dissimilation, simple nutritional requirements and high protein content, make C. jadinii a highly interesting platform for production of SCP and other products from ethanol.

Micronutrient Content of Aboveground Biomass as Influenced by Different Proportions of Medicago media Pers. in Two-Component Alfalfa–Grass Mixtures

The aim of this study was to determine the effect of different proportions of hybrid alfalfa (Medicago media Pers.) in two-component mixtures with festulolium (Festulolium braunii (K. Richt.) A. Camus) and orchard grass (Dactylis glomerata L.) on the micronutrient content of aboveground biomass. The study was conducted in 2011–2013 in Poland. The experiment had a split-plot design with four replications, and the experimental variables were as follows: (i) mixtures: Dactylis glomerata (Dg) + Medicago media (Mm) and Festulolium braunii (Fb) + Medicago media (Mm), and (ii) proportion of Medicago media seeds in the mixture: 30%, 50%, and 70%. Pure-sown Dactylis glomerata and pure-sown Festulolium braunii were the control treatments. The proportion of hybrid alfalfa in the biomass yield of mixtures increased throughout the study, and this species was the dominant component of the sward already in the second year, regardless of the proportion of sown seeds. Orchard grass exerted greater competitive pressure on alfalfa than festulolium. Pure-sown Dactylis glomerata accumulated more manganese (Mn) and iron (Fe) than pure-sown Festulolium braunii; no significant differences in the copper (Cu) and zinc (Zn) content of aboveground biomass were found between species. The aboveground biomass of mixtures was characterized by higher Cu content and lower Mn content than the biomass of grass monocultures. As a component of mixtures, alfalfa had a negative influence on the Fe content of aboveground biomass (dry matter basis). No significant differences in Cu and Mn content were observed between the mixtures. The Fb50% + Mm50% mixture had the highest Zn content, and the Fb70% + Mm30% mixture had the highest Fe content. The present findings suggest that practical two-component alfalfa–grass mixtures should be composed based on species competitiveness and selection of a grass component adapted to local agroecological conditions, rather than on the proportion of alfalfa seeds in the mixture.

Effects of Different Straw Incorporation Amounts on Soil Organic Carbon, Microbial Biomass, and Enzyme Activities in Dry-Crop Farmland

The direct input of straw to the field can increase the source and supply of soil carbon and nitrogen, change the soil microbial biomass and enzyme activity, and affect the soil organic carbon sequestration, which in turn affects soil fertility and quality. In this study, a three-year field orientation experiment was conducted to investigate the effects of straw input on soil microbial biomass, enzyme activity, and soil organic carbon at different straw incorporation amounts (0, 3000, 7000, and 14,000 kg/hm2). The results showed that soil microbial biomass, enzyme activity, and organic carbon content increased with the increase in straw amount, and the increase in 4-fold straw input (T4) treatment was significantly larger than that of other treatments; the microbial biomass, enzyme activity, and SOC (soil organic carbon) in different soil layers were 0–10 cm > 10–20 cm > 20–30 cm; and straw incorporation amounts had a significant effect on soil microbial biomass, enzyme activity, and SOC. The amount of straw input to the field had a highly significant positive effect on soil microbial carbon and nitrogen and SOC (p < 0.001). In conclusion, four times the amount of straw input to the field had the most obvious effect on enhancing soil organic carbon content, microbial biomass, and enzyme activity. This has important implications for the development of sustainable agriculture.

The influence of biostimulants used in the cultivation of Italian ryegrass (Lolium multiflorum Lam.) on nitrogen uptake and the efficiency of nitrogen fertilization

The aim of the study was to determine the effect of different biostimulants applied in the cultivation of Italian ryegrass cv. Dukat on nitrogen uptake and effectiveness of nitrogen fertilisation. A two-year field experiment was arranged as a randomised subblock design (split-plot) with three replicates. The following factors were examined: a) type of biostimulant: Algex, Tytanit, Asahi SL and a control (no biostimulant addition); b) nitrogen application rate: 0 (control), 120 and 180 kg ha–1. The total nitrogen content in the plant material was determined and nitrogen uptake with yield, agricultural and physiological efficiency were calculated. The application of biostimulants increased the nitrogen content in the Italian ryegrass biomass compared to the control. The differences between the tested biostimulants were insignificant. The amount of nitrogen in the biomass was significantly influenced by the rate of nitrogen. The effect of the year of the study was insignificant. The biostimulants used had a significant impact on the total nitrogen uptake during the vegetation year by Italian ryegrass. The values of this parameter depended on the type of biostimulant. Similarly, the value of this parameter was significantly affected by the year of the study, i.e. the total nitrogen uptake was significantly lower in the second year of the study. In the case of the agricultural efficiency fertilisation of Italian ryegrass, no significant differences were found for the influence of the tested experimental factors. The obtained values of the physiological efficiency fertilisation of Italian ryegrass fertilization did not differ significantly in the years of the study.

Removal efficiencies for 52 pesticides and pharmaceuticals from wastewater effluent by coupling solar heterogeneous photo-oxidation with TiO2 and infiltration in saturated soil column

Water resource management has become a hot button issue in recent decades. Countries facing water shortages as a result to climate change must adapt their water supply. The reuse of wastewater treatment plant effluents is becoming increasingly common around the world. However, the effluent quality must be improved before its reutilization to avoid contamination of the receiving environment. Pharmaceuticals and pesticides are particularly monitored because of their ubiquitous behaviours and limited removal by conventional wastewater treatment plants. The aim of this study was to combine heterogeneous photo-oxidation with TiO2 and soil infiltration to increase the elimination of contaminants of emerging concern (CECs). These advanced treatments were applied on an effluent coming from a WWTP equipped with a Ultrafor membrane bioreactor (sludge ages: 8–30 days, biomass concentration: 8-12 g.L−1, hydraulic retention: 6.7-8 h). The concentration of CECs was determined to evaluate the efficiency of coupling treatments. Photo-oxidation alone showed an impressive 98 % removal under spring conditions, while 66 % removal was observed under winter conditions. The differences observed for photo-oxidation were related to UV flux density, lower in winter than in spring (4.4 kJ.L−1 vs 6.6 kJ.L−1) and initial concentrations of the effluent higher in winter (50 μg.L−1 vs 26 μg.L−1). For both experiments, additional soil infiltration increased the global concentration of CECs removal to at least 89 % with equal removal contributions observed for some compounds. From the 52 CECs quantified in the WWTP effluent, at least 30 were totally removed by the advanced treatments while 4 compounds showed recalcitrant behaviours with global removal <60 %.

Scaling down recombinant carbonic anhydrase isolation with immobilized metal ion chromatography (IMAC): Harnessing enzymatic carbon dioxide capture and mineralization

BackgroundHuman activities have led to increased atmospheric CO2 levels, raising concerns about climate change. Carbonic anhydrase (CA) enzymes show promise for transforming CO2 into valuable products like calcium carbonate (CaCO3) through mineralization. Purifying and immobilizing CA enzymes on nanofiber membranes enhances their catalytic activity, enabling efficient CO2 conversion and mineralization. MethodsRecombinant CA was purified using immobilized metal affinity chromatography (IMAC), optimizing pH, biomass concentration, flow rate, and loading volume for maximum efficiency. The CA enzyme was then immobilized onto a weak ion exchange nanofiber membrane functionalized with AEA-COOH to create the CA-modified membrane (AEA-COOH-CA), enhancing CO2 conversion and CaCO3 mineralization. Significant findingsOptimal purification conditions (pH 7, 1 % biomass, 0.1 mL/min flow rate, 1.0 mL loading volume) were determined using IMAC. The CA-modified membrane effectively converted CO2 and mineralized CaCO3, demonstrating the potential for environmental CO2 sequestration. The immobilized CA activities of the AEA-COOH-CA nanofiber membranes exhibited 473.42 WAU/g-membrane, corresponding to 7.10 WAU per membrane piece. The CaCO3 precipitation reached 83.90 mg, with a precipitation efficiency of 11.82 mg CaCO3/WAU. These findings underscore the promise of enzymatic carbon capture using CA-modified membranes, offering a sustainable solution for greenhouse gas mitigation.

Restoration of degraded seagrass meadows: Effects of plant growth-promoting rhizobacteria (PGPR) inoculation on Zostera marina growth, rhizosphere microbiome and ecosystem functionality

The utilization of plant growth-promoting rhizobacteria (PGPR) holds great promise for the restoration of damaged terrestrial plant ecosystems. However, there is a significant knowledge gap regarding the application of PGPR in rehabilitating aquatic ecosystems. In this study, we conducted a mesocosm experiment to investigate the effects of Raoultella ornithinolytica F65, Pantoea cypripedii G84, Klebsiella variicola G85, Novosphingobium profundi G86, and Klebsiella pneumoniae I109 on eelgrass (Zostera marina L.), which is a crucial marine angiosperm. The application of these strains resulted in a significant increase in the new leaf area of eelgrass, with improvements of 55.4%, 14.4%, 39.1%, 20.6%, and 55.7% observed, respectively. Moreover, PGPR inoculation enhanced shoot biomass, rhizome elongation, leaf carbon and nitrogen content, as well as photosynthetic pigments. Furthermore, it stimulated enzymatic activities within the rhizosphere soil and positively influenced its physicochemical properties. The Illumina Miseq sequencing results revealed a positive shift in the bacterial community, leading to an enrichment of functional groups associated with nitrogen fixation and degradation of aromatic compounds. These findings underscore the significant potential of PGPR as a transformative tool for enhancing seagrass growth and survival, offering innovative strategies for the restoration of degraded seagrass meadows. This research not only advances our understanding of microbial-plant interactions in aquatic ecosystems but contributes to the broader goals of ecosystem revitalization and biodiversity conservation.

Contribution of Organic Carbon, Moisture Content, Microbial Biomass-Carbon, and Basal Soil Respiration Affecting Microbial Population in Chronosequence Manganese Mine Spoil

The research was carried out to determine the potential effect of microbiota, organic carbon, percentage of moisture content, and microbial biomass concentration as an evaluator of variation in basal soil respiration rate. Relative distribution and composition of the microbial population were estimated from six different chronosequence manganese mine spoil (MBO0, MBO2, MBO4, MBO6, MBO8, MBO10) and forest soil (FS). The variation was seen in moisture content (6.494±0.210-11.535±0.072)%, organic carbon (0.126±0.001- 3.469± 0.099)%, MB-C (5.519±1.371- 646.969± 11.428) μg.g-1 of soil. A positive correlation was shown between OC with MB-C (r = 0.938; p&lt; 0.01) and moisture content (MC) (r = 0.962; p&lt; 0.01). Variation in the basal soil respiration (BSR) and microbial metabolic quotients (MMQ) was shown to range between 0.352 ± 0.007- 0.958 ±0.014μg CO2-C.g-1 and 6.5× 10-3 - 1.481×10-3 μg CO2-C.g-1 microbial-C.h-1 with BSR: OC from (2.793-0.276)% respectively. This result shows that there is a gradual increase in OC, MC, MB-C, and BSR across seven different sites due to progressive enhancement in soil fertility that leads to the initialization of succession. Stepwise multiple regression analysis further confirms the degree of variability added by microbial biomass C, moisture content, organic carbon, and microbial population on basal soil respiration in microbes. Principal component analysis enables the differentiation of seven different soil profiles into independent clusters based on cumulative variance given by physico-chemical and microbial attributes that indicate the level of degradation of land and act as an index to restore soil fertility.

Development and application of a comprehensive numerical simulation model for microalgal pneumatic photobioreactors.

A novel and comprehensive multiphysics numerical simulation model for microalgal pneumatic photobioreactors was developed using the open-source Computational Fluid Dynamics (CFD) software OpenFOAM. This model integrates three distinct submodels: multiphase fluid dynamics, light transport, and microalgae growth. In particular, the light transport submodel accounts for light scattering caused by air bubbles. The model effectively addressed the challenges associated with the disparate time scales of the submodels, and its accuracy was validated by comparing with several experiments in different configurations. This study focuses on how an outdoor flat plate photobioreactor can maximize solar energy utilization. The results indicate that the daily productivity of the light-intensity adaptive reactor increased by 12.31% to 26.31% compared to those at constant biomass concentrations, demonstrating significant potential for employing this model in conjunction with automated systems to enhance productivity.

Comprehensive insight into recent algal enzymes production and purification advances: Toward effective commercial applications: A review.

Algal enzymes are essential catalysts in numerous biological reactions and industrial processes owing to their adaptability and potency. The marketing of algal enzymes has recently risen due to various reasons, including the cost-efficient manner of their cultivation in photobioreactors, the eco-friendly production of high biomass contents, sources of novel enzymes that used in many sectors (biofuel and bioremediation applications), sustainability, and more renewability. Oxidoreductases and hydrolytic enzymes are among the important applied algal enzymes in industrial applications, with annually growing demand. These algal enzymes have opened up new avenues for significant health advantages in reducing and treating oxidative stress, cardiovascular illness, tumors, microbial infections, and viral outbreaks. Despite their promising uses, commercial applications of algal enzymes face many difficulties, such as stability, toxicity, and lower data availability on specific and adequate catalytic mechanisms. Therefore, this review focuses on the algal enzyme types, their uses and advantages over other microbial enzymes, downstream and upstream processing, their commercial and marketing, and their challenges. With the constant development of novel enzymes and their uses, enzyme technology provides exciting options for several industrial sectors.

Enhanced Growth Performance and Steviol Glycosides Content in Stevia Rebaudiana Under Elevated Carbon Dioxide

In the current climate-changing scenario with a steadily rising CO2 concentration, there is a chance that crop performance will be affected in terms of growth, yield, and quality. Therefore, an experiment was conducted in a glasshouse using a randomized complete block design with four replications to investigate the effect of short and long-term elevated CO2 on growth performance and chemical markers of Stevia rebaudiana Bertoni. The CO2 in the glasshouse was gradually elevated from 400 ppm to 1800 ppm weekly. The plants were exposed to elevated CO2 for four months (T1), two months (T2), and one month (T3), while the control plants (T4) were grown under ambient CO2 (aCO2) levels to assess the effect of elevated atmospheric carbon dioxide (eCO2) on stevia crop growth performance and steviol glycosides content. The number of branches per plant, plant height, number of leaves per branch, and plant biomass were found to be significantly increased under eCO2 treatment over aCO2 treatment. The eCO2 increased photosynthetic rate by 46% for T1, 45% for T2, and 29% for T3 over control plants (T4) at 3rd month of planting. The enhancement in photosynthesis is attributed to an increase in stevioside; with a 33% increase for T1 28.83% for T2 and 11% for T3 over aCO2. Similarly, the rebaudiosides A were also significantly increased by 32.8% for T1, 25% for T2, and 15% for T3 compared to the control under aCO2. Based on our findings, we concluded that eCO2 levels positively influenced the growth, biomass, and glycoside content by enhancing the physiological performance of Stevia rebaudiana Bertoni.

Examining the efficacy of constructed wetland coupled microbial fuel cell to treat textile wastewater using local wetlands plant species.

Constructed wetland coupled microbial fuel cells (CW-MFC) offer a dual benefit of wastewater treatment and bioelectricity generation. While existing research predominantly emphasizes cell configuration, there is a limited exploration of the impact that various wetland plants may have on bioelectricity production in CW-MFCs. This research examined three distinct native wetland plants: Canna indica, Typha latifolia, and Eichhornia crassipes. The study centered on addressing textile wastewater treatment and assessing bio-electricity production. Over the course of 4weeks, regular assessments were conducted every 3rd day to monitor the alternations in the wastewater properties. The T. latifolia exhibited a chemical oxygen demand removal efficiency of 85.45%, surpassing that of E. crassipes (83.17%), C. indica (80.03%), mix culture (85.29%), and the control (unplanted) system (73.11%). Maximum removal efficacy of phosphate (96.84%) and nitrate (82.88%) was also achieved by the Typha plant in comparison to other plant species. An increase in both reactive biomass and chlorophyll content of Canna and Typha under single and mixed culture conditions was also observed. The highest current and voltage were obtained from T. latifolia plant species (1.04mA; 0.178V). Based on the findings of this study, T. latifolia emerged as the optimum wetland plant for bioelectricity generation and organic matter, phosphate, and ammonia removal among the examined plant species. Therefore, incorporating T. latifolia in the design of a CW-MFC is recommended for efficient textile wastewater and bioelectricity generation.

Bench scale Layer-by-Layer microencapasulation of Lactiplantibacillus plantarum WCFS1

Layer-by-Layer (LbL) self-assembly encapsulation is a promising technology for the protection and delivery of lactic acid bacteria. However, laboratory-scale encapsulation is often time-consuming, involves intensive protocols tailored for small-scale operations, requires substantial amounts of energy and water, and results in a low yield of encapsulated biomass. Scaling-up this process to a bench-bioreactor scale is not simply a matter of increasing culture volume as different key parameters (not particularly relevant at lab scale) become critical, including biomass production, the number of polymer layers, and the biomass-to-polymer mass ratio. To our knowledge, this work is the first to address the optimization of each stage of the encapsulation process for Lactiplantibacillus plantarum WCFS1. These stages include biomass production, handling of encapsulation polymers [chitosan (Chi) and alginate (Alg)], critical LbL parameters (e.g., biomass concentration, washing steps). The encapsulation efficiency was assessed by plate-counting microorganisms before and after coating with the polymers layers, followed by spray- and freeze-drying dehydration using fructo-oligosaccharides (FOS) and maltodextrin as carriers. Once dehydrated, microorganisms were either exposed to gastrointestinal conditions or stored for 30 days at 25 and 30 °C. Supplementing culture media with glucose, controlling pH, and harvesting at the early stationary phase during biomass production increased the bacterial recovery after LbL encapsulation (decrease < 1 log unit) compared to bacteria grown under non-controlled conditions (decrease of 4 log units). Coating bacteria (B) with up to two polymer layers (B|Chi or B|Chi|Alg) did not significantly affect bacterial culturability, unlike adding further layers. Zeta-potential measurements enabled the determination of the optimal biomass-to-polymer mass ratio. Using up to a 10:1 bacterial-to-polymer ratio did not change the z-potential for B|Chi or B|Chi|Alg samples. After drying, a synergistic effect between the LbL coating and carrier compounds (FOS and maltodextrin) was observed in terms of culturability. LbL encapsulation mitigated thermal and acidic stresses during spray-drying and gastrointestinal exposure. These findings support scaling-up LbL encapsulation for delivering sensitive lactic acid bacteria strains to the gut.