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Biohydrogen (Bio-H 2) is widely recognized as a sustainable and environmentally friendly energy source, devoid of any detrimental impact on the environment. Lignocellulosic biomass (LB) is a readily accessible and plentiful source material that can be effectively employed as a cost-effective and sustainable substrate for Bio-H 2 production. Despite the numerous challenges, the ongoing progress in LB pretreatment technology, microbial fermentation, and the integration of molecular biology techniques have the potential to enhance Bio-H 2 productivity and yield. Consequently, this technology exhibits efficiency and the capacity to meet the future energy demands associated with the valorization of recalcitrant biomass. To date, several pretreatment approaches have been investigated in order to improve the digestibility of feedstock. Nevertheless, there has been a lack of comprehensive systematic studies examining the effectiveness of pretreatment methods in enhancing Bio-H 2 production through dark fermentation. Additionally, there is a dearth of economic feasibility evaluations pertaining to this area of research. Thus, this review has conducted comparative studies on the technological and economic viability of current pretreatment methods. It has also examined the potential of these pretreatments in terms of carbon neutrality and circular economy principles. This review paves the way for a new opportunity to enhance Bio-H 2 production with technological approaches. • Lignocellulosic biomass is a sustainable feedstock for biohydrogen production. • To improve biohydrogen yields, lignocellulosic biomass requires pretreatment. • Utilizing advanced pretreatment approaches reduces by-product during H 2 production. • Nanoadditives can enhance biomass hydrolysis and biohydrogenation processes. • Biohydrogen production from lignocellulose may improve techno-economic feasibility. [ABSTRACT FROM AUTHOR]

THERE is an increasing worldwide demand for seafood due to the awareness of fish as an important protein source for a growing population. However, the diseases caused by multi-drug resistant (MDR) bacterial infections and the low survival rate of the fish represent significant challenges to fish farmers. The virulence and pathogenicity of bacteria are often enhanced when growing as a biofilm. Therefore, a variety of new antimicrobial drugs has attracted wide attention in treating fish pathogen bacteria. Herein, the efficiency of macroalgal extracts as an antibacterial agent against MDR Staphylococcus aureus bacteria isolated from Nile tilapia (Oreochromis niloticus) was studied. Out of 200 bacterial isolates, 50 strains were identified as S. aureus. Of these strains, 37 were MDR and showed a potential role in the production of virulence factors, including staphylokinase (70.2%), lecithinase (81%), protease (56.7%) and lipase (59.4%). Significant production of biofilm virulence factor by MDR S. aureus strains was also observed from the quantitative and qualitative analysis. Four algal species namely Jania rubens, Ulva lactuca, Sargassum vulgare, and Sargassum fusiforme were tested for their antibacterial activity against MDR S. aureus strains. Of those, S. vulgare diethyl ether extract showed the highest antibacterial. In addition, GC-MS analysis revealed 20 identified components in S. vulgare diethyl ether extract, in which Longifolene was dominant (16.5%). This study thus established the possibility of developing an antibacterial agent to combat developing MDR S. aureus and biofilm-related infections in Nile tilapia. [ABSTRACT FROM AUTHOR]

Copyright of Egyptian Journal of Botany is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Egyptian Journal of Experimental Biology (Botany) is the property of Egyptian Society of Experimental Biology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Egyptian Journal of Experimental Biology (Zoology) is the property of Egyptian Society of Experimental Biology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The presence of high salinity levels in textile wastewater poses a significant obstacle to the process of decolorizing azo dyes. The present study involved the construction of a yeast consortium HYC, which is halotolerant and was recently isolated from wood-feeding termites. The consortium HYC was mainly comprised of Sterigmatomyces halophilus SSA-1575 and Meyerozyma guilliermondii SSA-1547. The developed consortium demonstrated a decolourization efficiency of 96.1% when exposed to a concentration of 50 mg/l of Reactive Black 5 (RB5). The HYC consortium significantly decolorized RB5 up to concentrations of 400 mg/l and in the presence of NaCl up to 50 g/l. The effects of physicochemical factors and the degradation pathway were systematically investigated. The optimal pH, salinity, temperature, and initial dye concentration were 7.0, 3%, 35 °C and 50 mg/l, respectively. The co-carbon source was found to be essential, and the addition of glucose resulted in a 93% decolorization of 50 mg/l RB5. The enzymatic activity of various oxido-reductases was assessed, revealing that NADH-DCIP reductase and azo reductase exhibited greater activity in comparison to other enzymes. UV-Visible (UV–vis) spectrophotometry, Fourier-transform infrared spectroscopy (FTIR), high-performance liquid chromatography (HPLC), and gas chromatography–mass spectrometry (GC-MS) were utilized to identify the metabolites generated during the degradation of RB5. Subsequently, a metabolic pathway was proposed. The confirmation of degradation was established through alterations in the functional groups and modifications in molecular weight. The findings indicate that this halotolerant yeast consortium exhibits promising potential of degrading dye compounds. The results of this study offer significant theoretical basis and crucial perspectives for the implementation of halotolerant yeast consortia in the bioremediation of textile and hypersaline wastewater. This approach is particularly noteworthy as it does not produce aromatic amines. • HYC is a promising halotolerant yeast consortium for azo dye degradation. • HYC decolorized Reactive Black 5 (RB5) up to 400 mg/l and 50 g/l NaCl. • GC-MS, FTIR, and enzyme analysis are used to study decolorization mechanism. • Environmental and nutritional factors affecting RB5 decolorization are discussed. • HYC provides a useful strategy to remediate dyeing contaminated saline wastewater. [ABSTRACT FROM AUTHOR]

The pathophysiology of chronic kidney disease (CKD) is driven by alterations in surviving nephrons to sustain renal function with ongoing nephron loss. Oxygen supply-demand mismatch, due to hemodynamic adaptations, with resultant hypoxia, plays an important role in the pathophysiology in early CKD. We sought to investigate the underlying mechanisms of this mismatch. We utilized the subtotal nephrectomy (STN) model of CKD to investigate the alterations in renal oxygenation linked to sodium (Na) transport and mitochondrial function in the surviving nephrons. Oxygen delivery was significantly reduced in STN kidneys because of lower renal blood flow. Fractional oxygen extraction was significantly higher in STN. Tubular Na reabsorption was significantly lower per mole of oxygen consumed in STN. We hypothesized that decreased mitochondrial bioenergetic capacity may account for this and uncovered significant mitochondrial dysfunction in the early STN kidney: higher oxidative metabolism without an attendant increase in ATP levels, elevated superoxide levels, and alterations in mitochondrial morphology. We further investigated the effect of activation of hypoxia-inducible factor-1α (HIF-1α), a master regulator of cellular hypoxia response. We observed significant improvement in renal blood flow, glomerular filtration rate, and tubular Na reabsorption per mole of oxygen consumed with HIF-1α activation. Importantly, HIF-1α activation significantly lowered mitochondrial oxygen consumption and superoxide production and increased mitochondrial volume density. In conclusion, we report significant impairment of renal oxygenation and mitochondrial function at the early stages of CKD and demonstrate the beneficial role of HIF-1α activation on renal function and metabolism. [ABSTRACT FROM AUTHOR]

Pectin and chitosan are natural polysaccharides obtained from fruit peels and exoskeletons of crustaceans and insects. They are safe for usage in food products and are renewable and biocompatible. They have further applications as wound dressings, body fat reduction, tissue engineering, and auxiliary agents in drug delivery systems. The healing process is usually long and painful. Adding a new material such as a pectin-chitosan composite to the implant surface or body would create unique biological responses to accelerate healing and delivery of target-specific medication at the implant site. The present study utilized the electrospraying process to create pectin-chitosan polyelectrolyte composite (PCPC) coatings with various ratios of 1:1, 2:1, 1:2, 1:3, and 3:1 on commercially pure titanium substrates. By means of FESEM, AFM, wettability, cross-cut adhesion, and microhardness were assessed the PCPC coatings' physical and mechanical properties. Subsequently, the antibacterial properties of the coating composite were assessed. AFM analysis revealed higher surface roughness for group 5 and homogenous coating for group 1. Group 3 showed the lowest water contact angle of 66.7° and all PCPC coatings had significantly higher Vickers hardness values compared to the control uncoated CpTi samples. Groups 3 and 4 showed the best adhesion of the PCPC to the titanium substrates. Groups 3, 4, and 5 showed antibacterial properties with a high zone of inhibitions compared to the control. The PCPC coating's characteristics can be significantly impacted by using certain pectin-chitosan ratios. Groups 3 (1:2) and 4 (1:3) showed remarkable morphological and mechanical properties with better surface roughness, greater surface strength, improved hydrophilicity, improved adhesion to the substrate surface, and additionally demonstrated significant antibacterial properties. According to the accomplished in vitro study outcomes, these particular PCPC ratios can be considered as an efficient coating for titanium dental implants. [ABSTRACT FROM AUTHOR]

The abundance of synthetic polymers has become an ever-increasing environmental threat in the world. The excessive utilization of plastics leads to the accumulation of such recalcitrant pollutants in the environment. For example, during the COVID-19 pandemic, unprecedented demand for personal protective equipment (PPE) kits, face masks, and gloves made up of single-use items has resulted in the massive generation of plastic biomedical waste. As secondary pollutants, microplastic particles (<5 mm) are derived from pellet loss and degradation of macroplastics. Therefore, urgent intervention is required for the management of these hazardous materials. Physicochemical approaches have been employed to degrade synthetic polymers, but these approaches have limited efficiency and cause the release of hazardous metabolites or by-products into the environment. Therefore, bioremediation is a proper option as it is both cost-efficient and environmentally friendly. On the other hand, plants evolved lignocellulose to be resistant to destruction, whereas insects, such as wood-feeding termites, possess diverse microorganisms in their guts, which confer physiological and ecological benefits to their host. Plastic and lignocellulose polymers share a number of physical and chemical properties, despite their structural and recalcitrance differences. Among these similarities are a hydrophobic nature, a carbon skeleton, and amorphous/crystalline regions. Compared with herbivorous mammals, lignocellulose digestion in termites is accomplished at ordinary temperatures. This unique characteristic has been of great interest for the development of a plastic biodegradation approach by termites and their gut symbionts. Therefore, transferring knowledge from research on lignocellulosic degradation by termites and their gut symbionts to that on synthetic polymers has become a new research hotspot and technological development direction to solve the environmental bottleneck caused by synthetic plastic polymers. • Synthetic plastic polymers are one the most environmental challenges worldwide. • COVID-19 paved the way for massive amounts of plastic wastes, including face masks. • Impacts of plastic waste on the environment and human health are reviewed. • There is much to learn from termites regarding recalcitrant biomass biodegradation. • It could unveil possible strategy for plastic degradation by termite/gut symbionts. [ABSTRACT FROM AUTHOR]

Wastewater treatment including microalgae is an economically promising and environmentally friendly alternative to conventional wastewater treatment due to the concurrent nutrient removal and production of high-value biomass. This work aimed to choose the most suitable type of wastewater and its appropriate dilution for sustaining microalgal growth by testing unialgal versus mixed microalgae cultures and raw versus autoclaved wastewater. Based on pilot experiments including microplate screening, unialgal cultures of Chlorella emersonii grown in 1:5 diluted, non-autoclaved wastewater were selected as the optimum scenario for further testing. In the main experiments, Chlorella emersonii was cultivated in Erlenmeyer flasks and bubble column reactors. Additionally, a photoautotrophic biofilm was grown in flumes. We studied three types of wastewater originating from a large municipal wastewater treatment plant, a brewery, and a dairy. Dairy wastewater performed best in all cultivation systems and resulted in a maximum biomass per irradiated area of around 145 μg cm−2 chlorophyll-a of Chlorella cultures in bubble columns, followed by 105 μg cm−2 in flumes run by a photoautotrophic biofilm. Furthermore, phosphorus reduction of 96 % for dairy, 40 % for the brewery, and 43 % for municipal wastewater were achieved in the flumes. Due to the easy harvest of algae biomass, low construction and operation costs, flumes represent a recommendable cultivation system for dairy wastewater treatment on a larger scale. [Display omitted] • Dairy wastewater performed better than brewery and municipal wastewater. • Non-autoclaved wastewater, diluted to the fifth part, performed best. • Bubble column reactors and flumes yielded comparable algal biomass. • A phosphorus reduction rate of 96 % was achieved in the flumes. • Flumes run with mixed phototrophic biofilms are recommended for wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel bacterial isolate was enriched from the wood-feeding termite, Microcerotermes. • The isolate was identified as Streptomyces sp. strain MS-S2. • Streptomyces sp. strain MS-S2 exhibited xylanolytic and cellulolytic properties. • The MS-S2 strain utilized wheat straw for optimal cellulase and xylanase secretion. • The obtained enzymes could potentially hydrolyze wheat straw for ethanol production. Lignocellulosic biomass represents an unlimited and ubiquitous energy source, effectively addressing current global energy demand challenges. However, the recalcitrant nature of lignocellulose hinders microbial degradation, necessitating an appropriate hydrolytic enzyme production source for biomass valorisation and bioethanol production. This study might be the first to explore a novel bacterial species Streptomyces sp. strain MS-S2, isolated from the higher wood-feeding termite, Microcerotermes sp.; capable of concurrent degradation and saccharification of wheat straw for the liberation of reducing sugars, which can further be converted to bioethanol. The Streptomyces sp. MS-S2 demonstrated the capacity to efficiently utilise wheat straw as the sole carbon source for the secretion of xylanase and cellulase enzymes. The highest cellulase and xylanase productions were observed for ten days when the bacterium was cultured in the medium amended with 15 g/L of wheat straw and 1.5% yeast extract at pH 8.0, 30 ℃. Under optimum conditions, xylanase and cellulase activities were estimated to be 6.560 ± 0.160 and 0.866 ± 0.067 U/mL, respectively. Through Scanning electron microscopy analysis, the surface accessibility of cellulose fibrils in treated wheat straw was observed, indicating the efficiency of the hydrolysis process. In addition, functional group modifications from Fourier transform infrared spectroscopy analysis demonstrated the successful depolymerisation of wheat straw. Further, excreted enzymes produced under optimal conditions were applied to wheat straw hydrolysis for the liberation of reducing sugars. Then, ethanol production was obtained at a maximum concentration of 10.8 g/L. The findings of this study could open a new path for the search of new lignocellulolytic-producing bacteria inhabiting the gut symbionts of wood-feeding termites to valorise lignocellulosic biomass into biotechnologically value-added products such as biofuels. [ABSTRACT FROM AUTHOR]

The synthetic dyes used in the textile industry pollute a large amount of water. Textile dyes do not bind tightly to the fabric and are discharged as effluent into the aquatic environment. As a result, the continuous discharge of wastewater from a large number of textile industries without prior treatment has significant negative consequences on the environment and human health. Textile dyes contaminate aquatic habitats and have the potential to be toxic to aquatic organisms, which may enter the food chain. This review will discuss the effects of textile dyes on water bodies, aquatic flora, and human health. Textile dyes degrade the esthetic quality of bodies of water by increasing biochemical and chemical oxygen demand, impairing photosynthesis, inhibiting plant growth, entering the food chain, providing recalcitrance and bioaccumulation, and potentially promoting toxicity, mutagenicity, and carcinogenicity. Therefore, dye-containing wastewater should be effectively treated using eco-friendly technologies to avoid negative effects on the environment, human health, and natural water resources. This review compares the most recent technologies which are commonly used to remove dye from textile wastewater, with a focus on the advantages and drawbacks of these various approaches. This review is expected to spark great interest among the research community who wish to combat the widespread risk of toxic organic pollutants generated by the textile industries. [Display omitted] • Textile dyes are toxic and discharged as effluent into the aquatic environment. • Non-pretreated effluent has significant negative impacts on living microorganisms. • Dye-containing wastewater should be effectively treated using eco-friendly methods. • Combined approaches and recent technologies are promising for dye removal. • More research is required until an advanced, zero-waste process is established. [ABSTRACT FROM AUTHOR]

Adult exposure to NMDA receptor antagonists, such as ketamine, produces psychosis in humans, and exacerbates symptoms in schizophrenic patients. We recently showed that ketamine activates the innate immune enzyme NADPH-oxidase in brain, and that the superoxide produced leads to dysfunction of a subset of fast-spiking inhibitory interneurons expressing the calcium-binding protein parvalbumin (PV). Here we show that neuronal production of interleukin-6 (IL-6) is necessary and sufficient for ketamine-mediated activation of NADPH-oxidase in brain. Removal of IL-6 in neuronal cultures by anti-IL-6 blocking antibodies, or in vivo by use of IL-6-deficient mice, prevented the increase in superoxide by ketamine and rescued the interneurons. Accumulating evidence suggests that schizophrenia patients suffer from diminished antioxidant defenses, and a recent clinical trial showed that enhancing these defenses may ameliorate symptoms of the disease. Our results showing that ketamine-induced IL-6 is responsible for the activation of NADPH-oxidase in brain suggest that reducing brain levels of this cytokine may protect the GABAergic phenotype of fast-spiking PV-interneurons and thus attenuate the propsychotic effects of ketamine. [ABSTRACT FROM AUTHOR]

Superoxide, a potentially toxic by-product of cellular metabolism, may contribute to tissue injury in many types of human disease. Here we show that a tris-malonic acid derivative of the fullerene C60 molecule (C3) is capable of removing the biologically important superoxide radical with a rate constant (kC3) of 2 × 106 mol−1 s−1, approximately 100-fold slower than the superoxide dismutases (SOD), a family of enzymes responsible for endogenous dismutation of superoxide. This rate constant is within the range of values reported for several manganese-containing SOD mimetic compounds. The reaction between C3 and superoxide was not via stoichiometric “scavenging,” as expected, but through catalytic dismutation of superoxide, indicated by lack of structural modifications to C3, regeneration of oxygen, production of hydrogen peroxide, and absence of EPR-active (paramagnetic) products, all consistent with a catalytic mechanism. A model is proposed in which electron-deficient regions on the C60 sphere work in concert with malonyl groups attached to C3 to electrostatically guide and stabilize superoxide, promoting dismutation. We also found that C3 treatment of Sod2 −/− mice, which lack expression of mitochondrial manganese superoxide dismutase (MnSOD), increased their life span by 300%. These data, coupled with evidence that C3 localizes to mitochondria, suggest that C3 functionally replaces MnSOD, acting as a biologically effective SOD mimetic. [Copyright &y& Elsevier]

Simple Summary: The accumulation of recalcitrant pollutants (e.g., lignin biomass and synthetic textile dyes) in diverse ecosystems has exacerbated the problem of environmental pollution. The complex polymer structure of lignin brings huge challenges to the development of high-efficiency transformation technology, making it difficult to realize its industrial utilization. On the other hand, the use of dyes in the textile industry poses significant challenges worldwide. Dyes are very similar to lignin biomass in chemical structure. Similarly, under natural conditions, it is difficult for microorganisms in the environment to achieve rapid biodegradation and complete detoxification. Clearly, the integration of bioremediation and biorefinery technology towards such recalcitrant organic wastes is considered a novel concept for mitigating the toxicity of such pollutants using termite gut symbionts. Modern biorefinery and bioremediation applications can integrate the termite gut system, a unique bioresource that comprises distinct bacterial species valued for lignocellulosic material processing and synthetic dye degradation. Therefore, this review paper provides a new strategy for efficient management of recalcitrant pollutants by exploring the potential application of termite gut bacteria in terms of science and industry. Lignocellulosic biomass (LCB) in the form of agricultural, forestry, and agro-industrial wastes is globally generated in large volumes every year. The chemical components of LCB render them a substrate valuable for biofuel production. It is hard to dissolve LCB resources for biofuel production because the lignin, cellulose, and hemicellulose parts stick together rigidly. This makes the structure complex, hierarchical, and resistant. Owing to these restrictions, the junk production of LCB waste has recently become a significant worldwide environmental problem resulting from inefficient disposal techniques and increased persistence. In addition, burning LCB waste, such as paddy straws, is a widespread practice that causes considerable air pollution and endangers the environment and human existence. Besides environmental pollution from LCB waste, increasing industrialization has resulted in the production of billions of tons of dyeing wastewater from several industries, including textiles, pharmaceuticals, tanneries, and food processing units. The massive use of synthetic dyes in various industries can be detrimental to the environment due to the recalcitrant aromatic structure of synthetic dyes, similar to the polymeric phenol lignin in LCB structure, and their persistent color. Synthetic dyes have been described as possessing carcinogenic and toxic properties that could be harmful to public health. Environmental pollution emanating from LCB wastes and dyeing wastewater is of great concern and should be carefully handled to mitigate its catastrophic effects. An effective strategy to curtail these problems is to learn from analogous systems in nature, such as termites, where woody lignocellulose is digested by wood-feeding termites and humus-recalcitrant aromatic compounds are decomposed by soil-feeding termites. The termite gut system acts as a unique bioresource consisting of distinct bacterial species valued for the processing of lignocellulosic materials and the degradation of synthetic dyes, which can be integrated into modern biorefineries for processing LCB waste and bioremediation applications for the treatment of dyeing wastewaters to help resolve environmental issues arising from LCB waste and dyeing wastewaters. This review paper provides a new strategy for efficient management of recalcitrant pollutants by exploring the potential application of termite gut bacteria in biorefinery and bioremediation processing. [ABSTRACT FROM AUTHOR]