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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 lignocellulosic biomass render them a substrate valuable for biofuel production. However, the rigid association of lignin, cellulose, and hemicellulose component of LCB forms a complex, hierarchical, and recalcitrant structure, which inhibits the solubilization of LCB resources for biofuel production. The learning from termites (wood-feeding and soil-feeding) and further application of their gut bacteria for lignin degradation and bioconversion remain unexplored or at its early stage. With reference to this scientific knowledge gap, this study seeks to highlight the culturable gut bacterial community in soil- and wood-feeding termites, namely Pericapritermes nitobeiand Microcerotermessp., respectively to design a future biorefinery and bioremediation technologies. In this study, a total of 40 and 67 bacterial isolates were indeed identified from Pericapritermes nitobeiand Microcerotermessp., respectively. The identified isolates from both termite species were actually classified into four different phyla: Actinobacteria, Proteobacteria, Firmicutes, and Bacteroidetes, where the phylum Actinobacteria dominated gut bacteria isolates identified from P. nitobeiat 47.5 % while Proteobacteria were dominant in wood-feeding termite, Microcerotermessp. at 46.27 %. At the genus level, the bacterial isolates enriched from the gut of Microcerotermessp. belonged to 17 different genera, among which the bacterial genus Streptomyces(28 %) was most prevalent, followed by Enterobacter(11 %). Meanwhile, 9 genera were recorded for gut bacterial isolates from P. nitobeiand were dominated by Streptomyces(37.5 %), followed by Acinetobacter(25 %). In general, the gut bacterial symbionts from both termites showed a congruency at the phyla level but were more diverged at a lower classification, inferring that different termite species evolved a unique repertoire of gut bacteria. Moreover, 61 % and 55 % of the gut bacterial isolates from the wood- and soil-feeding termites demonstrated a significant and multifunctional role in the hydrolysis of three lignocellulolytic substrates, including carboxymethyl cellulose, beechwood xylan, and aniline blue dye, indicating their unique functions and assistance to the host for the degradation of lignocellulose or other xenobiotic compounds from soil.

Global energy demands are increasing rapidly, and the pursuit of renewable energy sources has the potential to mitigate climate change. Biohydrogen production is regarded as a highly promising alternative approach for producing hydrogen, owing to its efficiency, renewable nature, and environmental friendliness in comparison to conventional approaches. A substantial amount of attention has been paid to the production of biohydrogen using microalgae as a source of energy that is both sustainable and clean. When it comes to producing biohydrogen from microalgae, there are a few different approaches that can be explored. This study explores various mechanisms for the production of hydrogen gas by microorganisms. It also provides insights on the recent advancements in biohydrogen production. Furthermore, it analyzes the significant challenges confronted during the biohydrogen production process and comprehends future perspectives adopted to enhance hydrogen productivity. This study emphasizes the necessity for commercial biohydrogen production research to reduce the gap between realistic and practical techno-economic viability applications.

The global issue of synthetic plastic pollution is escalating, necessitating innovative bioremediation approaches. Specific insect species have developed symbiotic associations with intestinal microorganisms that possess the ability to degrade resistant plant materials, such as lignocellulose. This is the first study to our knowledge to isolate, characterize, and compare microbial isolates (yeast and bacteria) extracted from the guts of wood-feeding termites (WFT) and lesser waxworms (LWW). The objective was to determine their efficacy in decomposing recalcitrant pollutants, such as low-density polyethylene (LDPE). The isolates belonged to numerous taxonomic groups, as determined by molecular identification; these groups included Bacillus, Citrobacter, Cellulosimicrobium, Rhodococcus, Pseudomonas, Candida, and others. A number of isolates had the potential to degrade LDPE. After 45 days of incubation, the polymer sheets lost 19.8 % of their weight for Bacillus cereus(LDPE-DB2) and 15.4 % of their weight for Candida guilliermondii(LDPE-DY6). Additionally, LDPE degraded by LDPE-DY6 showed a tensile strength loss of 50.3 % compared to that degraded by LDPE-DB2 (58.3 %). During this time, robust biofilm formation was observed on the surfaces of the polymers. Extracellular enzymes such as cutinases, aryl alcohol oxidases, and peroxidases, secreted by specific yeast and bacterial isolates, contribute to the degradation of plastic and recalcitrant biopolymers. Notably, the isolates from LWW demonstrated a greater advantage in this regard than those from WFT. Bacillus cereus, Pseudomonas aeruginosa, Candida guilliermondii, and Sterigmatomyces halophiluswere found to have the highest activities in degrading LDPE among the studied WFT and LWW gut-derived symbionts. This study paves the way for a new opportunity to enhance polyethylene degradation by insect gut bacteria and yeasts that may facilitate biotechnological applications for plastic waste remediation.

Lignin and synthetic dyes share complex structural similarities and relevant management difficulties, which should be effectively addressed towards environmental sustainability. Under this scope, the quest for oxidative enzyme-producing microorganisms with a view to efficiently valorizing organic pollutants is of utmost importance. The intestinal bacteria of wood-feeding termites represent a unique source of valuable enzymes. The decolorization efficiency of five different dyes, including malachite green (MG), methyl violet, anihiline blue, reactive red, and reactive blue, after 12 h of degradation by the MS-S2 bacterial strain was recorded to be 98.2, 17.5, 8.7, 4.6, and 3.28%, respectively. Several physico-chemical parameters were then optimized to accelerate MG degradation, including pH, temperature, glucose, and yeast extract concentration. Streptomycessp. strain MS-S2 completely decolorized MG (50 mg/L) within 2 h under optimized conditions when the cultivation medium was amended with 5 g/L glucose and 0.08 g/L yeast extract at pH 8 and incubated at 28 °C. After MG degradation, the enzyme activities of manganese peroxidase (4.605 U/L) and laccase (45.185 U/L) were estimated. To comprehend the degradation process of MG by the MS-S2 strain, UV-Vis spectroscopy, Fourier transform infrared (FTIR), and gas chromatography-mass spectrometry (GC-MS) analyses were carried out to ascertain the possible degradation mechanism. The metabolites identified, such as 2,6-Bis (tert-butyl) phenol and [4-(dimethylamino) phenyl] phenyl, suggest that MG was broken down into less toxic compounds for further degradation. MS-S2 exhibited outstanding characteristics that could make it suitable for the bioremediation of MG dye in an industrial setting.

An annual reduction in processing expenses results in the direct discharge of millions of litters of diverse wastewater into the environment, which causes eutrophication and depletes pure water sources. Traditional physicochemical treatment are widely employed for wastewater treatment (WWT). However, the optimal functioning of these systems necessitates significant operating and maintenance expenditures and the use of unique technologies for sludge treatment and disposal. One of the most crucial processes in a biorefinery is the effective pretreatment of industrial wastewater, which ensures the bioprocess overall quality and commercial feasibility. Industrial WWT is essential for improving biorefinery and valorization processes for producing biofuels, bioenergy, chemicals, and other valuable products. Consequently, industrial effluent must be managed to facilitate further bioprocessing. Bioelectrochemical systems (BESs) are an emerging field utilized for the removal of organic matter from industrial wastewater, desalination of seawater, and production of bioelectricity. In the distant future, the utilization of BESs will be focused on environmental remediation, WWT, bioanalysis, and the reduction of toxic gas emissions. In recent years, there has been a surge in research endeavors pertaining to BESs, specifically microbial fuel cells (MFCs), microbial electrolysis cells (MECs), microbial desalination cells (MDCs), and microbial electrolysis desalination cells (MEDCs), in an effort to produce energy that is both environmentally friendly and sustainable. This review focuses on the applicability of various advanced treatment approaches for industrial wastewater or sludge and the separation of recovered products from wastewater and its residues. It also highlights the basic operational characteristics of the MFCs, MECs, MDCs, and MEDCs using wastewater. The cutting-edge data presented in this review could improve further interdisciplinary and translational research.

The Pan-Drug Resistant (PDR), Helicobacter pyloriremains an intractable challenge in public health worldwide and this pathogenicity is mainly due to the presence of a cytotoxin-associated gene A (CagA) and vacuolating cytotoxin A (VacA). On the other hand, plant extracts such as Syzygium aromaticumcontain a diverse array of secondary metabolites, which could be potentially used to combat H. pyloripathogens. To our knowledge, this is the first report on the biomedical potential of S. aromaticumextract against cytotoxin-associated genes producing PDR H. pylori. In this investigation, out of 45 gastric antral biopsy specimens of dyspeptic patients, 20 strains were confirmed as H. pylori.Eight (40%) out of 20 strains were PDR H. pyloriwhile the rest of the strains were Multi-Drug Resistant (MDR) strains. Genotypic analyses of PDR H. pyloristrains showed that cagAand vacAgenes were found to be 75% and 87.5%, respectively and m2s2was the most common subtype of vacAgene. S. aromaticumshowed a significant higher anti-H. pyloriactivity compared to that of Cinnamomum zeylanicumand Thymus vulgaris. Eugenol was the major phenolic compound (28.14%) detected in the methanolic extract of S. aromaticum. Clearly, results of the toxicological assessment confirmed the safety of S. aromaticumfor use. Hence, these results suggest that S. aromaticumcould be a new useful natural antimicrobial agent that could potentially combat cytotoxin genes-producing drug-resistant H. pylori. Moreover, these findings provide a scientific basis for the development of antimicrobial agents from traditional herbal medicines for gastroprotection against gastric ulcer.

The Multidrug Drug Resistance (MDR) and Pan-Drug Resistance (PDR) remain an intractable challenge issue in public health, worldwide. Plant extracts-based biological macromolecules containing a diverse array of secondary metabolites could be potentially used as alternative approaches to control or limit MDR/PDR infections. Plants of the Solanaceae family exhibit a wide variety of secondary metabolites with antioxidant and antimicrobial properties, which render them a significant role in food and pharmaceutical applications. To our knowledge, this is the first report on phytochemical constituents, antioxidant, antimicrobial activities and in vivotoxicological safety of Lycium shawiileaf extracts. Results revealed that phenolics and flavonoids were found to be the most abundant compounds in all extracts. Antioxidant activity of extracts was measured using DPPH•and ABTS•+assays and the methanol extract displayed superior scavenging activity (IC50 = 0.06 and 0.007 mg/mL for DPPH•and ABTS•+, respectively). Results of the GC-MS analysis revealed the identity of 10 compounds. Moreover, in vivotoxicological assessment can confirm the safety of L. shawiifor use. Overall, L. shawiileaves are a promising natural source for the development of novel antimicrobial and antioxidant agents that could potentially combat clinical MDR/PDR pathogens.

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.

Beyond energy crises, biodiesel offers renewable and unlimited option to the challenges associated with fossil fuels depletion. Biodiesel could reduce the carbon foot print and gas emissions. Therefore, China has set an audacious goal of carbon neutrality by 2060. In order to reduce the cost of biodiesel production, it is critical to look for alternative feedstocks and unconventional resources. Biodiesel can be produced from renewable and sustainable feedstocks like edible and non-edible oils, insect, municipal sewage sludge, and oleaginous microorganisms. Existing life cycle assessments of yeast-based biodiesel production are required to assess potential environmental impacts and obtain a holistic picture. The circular economy paradigm has recently emerged as a viable alternative to linear, unsustainable production and consumption systems. Given the legislative requirements and the circular economy principle, the use of textile azo dye wastewater is a promising alternative for its management. The annual disposal of 4,500,000 tons of textile dyes is an environmental and socioeconomic concern due to their carcinogenic potential. Azo dyes account for over 70% of global industrial demand. Biological-mediated azo dye degradation is thought to be cost-effective, and environmentally friendly when compared to physical and chemical approaches. To this end, yeasts can play a significant role, owing to their high growth rate, tolerance to extreme conditions, and ability to effectively degrade lignin and aromatic compounds, concurrently representing a highly promising feedstock for biodiesel production. Interestingly, an emphasis has been recently given on novel symbiotic yeasts isolatedfrom termite gutsas promising microbiomes for multiple biotechnological applications. Therefore, this review focuses on recent findings of biodiesel production from azo dye degrading yeasts inhabiting termite guts. While capturing recent research advancements for sustainable biodiesel production, this review emphasizes a novel concept for using azo dyes/aromatic wastes as a feedstock for biodiesel production.

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