Immediate health risk: Concentration of heavy metals in contaminated freshwater fishes from the river channel of Turag-Tongi-Balu.

The consumption of contaminated finfish from the polluted river channel of Turag-Tongi-Balu, Kamarpara site, Dhaka poses significant health hazards to humans. We used mass spectrometry on chemically digested liquid samples from five fish species from Turag-Tongi-Balu to estimate the concentrations of 10 elements (Cr, Mn, Ni, Cu, Zn, As, Se, Cd, Fe, and Pb). Except M. vittatus, the mean concentrations of Cd, Mn, Pb, and Se exceeded the Food Safety Guideline (FSG) value in all fish species. Among the species studied, L. rohita, C. punctata, C. batrachus, H. fossilis, and M. vittatus exhibited higher Mn concentrations surpassing the FSG threshold, thus elevating the non-carcinogenic risk across all species. There were statistically significant differences (p < .05) in the mean concentrations of heavy metals among fish species. The Target Hazard Quotient (THQ) value of Mn poses a significant non-carcinogenic risk to human health, while the hazard of other metals is negligible. Except for M. vittus, the Hazard Index value (HI ≥ 1) revealed the risk that all metals exceed the limit and pose a threat to human health. Cd, As, and Ni metals pose a significant carcinogenic risk to human health from the consumption of fish samples, which is a particularly alarming target cancer risk (TCR). In conclusion, regular dietary consumption of fish from this polluted ecosystem of the Turag-Tongi-Balu River channel's Kamarpara site poses a significant health risk and is indicated as cancer. This study emphasizes the significance of monitoring heavy metal contamination in finfish and minimizing the risk to human health with effective measures.

Antibacterial and antibiofilm activities of diphyllin against fish pathogens.

Annihilation of biofilm forming bacterial pathogens is a challenging aspect in seafood and aquaculture industries. Microbes growing as biofilms cause deleterious effects on food products leading to food spoilage or loss of shelf life. As a measure to fight biofilms, agents that prevent/disrupt biofilms are recurrently screened. The study exemplifies the bactericidal and biofilm disruption potentials of a plant derived compound, diphyllin, against fish pathogens that colonizes Oreochromis mossambicus and Oreochromis niloticus. Precisely, diphyllin disrupted Salmonella typhi biofilms by triggering reactive oxidative species (ROS). Diphyllin-induced ROS had satisfactory correlation with S. typhi cell membrane damage and intracellular DNA degradation profiles providing a putative mechanistic model. In conclusion, the study identifies diphyllin as a therapeutic and dispersal agent aimed at biofilms formed by food-borne pathogens that persistently plague food processing and aquaculture settings.

2-Furaldehyde diethyl acetal from tender coconut water (Cocos nucifera) attenuates biofilm formation and quorum sensing-mediated virulence of Chromobacterium violaceum and Pseudomonas aeruginosa.

The aim of this study was to evaluate the anti-biofilm and quorum sensing inhibitory (QSI) potential of tender coconut water (TCW) against Chromobacterium violaceum and Pseudomonas aeruginosa. TCW significantly inhibited the QS regulated violacein, virulence factors and biofilm production without affecting their growth. qRT-PCR analysis revealed the down-regulation of autoinducer synthase, transcriptional regulator and virulence genes. Mass-spectrometric analysis of a petroleum ether extract of the TCW hydrolyte revealed that 2-furaldehyde diethyl acetal (2FDA) and palmitic acid (PA) are the major compounds. In vitro bioassays confirmed the ability of 2FDA to inhibit the biofilm formation and virulence factors. In addition, the combination of PA with 2FDA resulted in potent inhibition of biofilm formation and virulence factors. The results obtained strongly suggest that TCW can be exploited as a base for designing a novel antipathogenic drug formulation to treat biofilm mediated infections caused by P. aeruginosa.

Directional co-immobilization of artificial multimeric-enzyme complexes as a robust biocatalyst for biosynthesis curcumin glucosides and regeneration of UDP-glucose.

Site-directed protein immobilization allows the homogeneous orientation of proteins while maintaining high activity, which is advantageous for various applications. In this study, the use of SpyCatcher/SpyTag technology and magnetic nickel ferrite (NiFe2O4 NPs) nanoparticles were used to prepare a site-directed immobilization of BsUGT2m from Bacillus subtilis and AtSUSm from Arabidopsis thaliana for enhancing curcumin glucoside production with UDP-glucose regeneration from sucrose and UDP. The immobilization of self-assembled multienzyme complex (MESAs) enzymes were characterized for immobilization parameters and stability, including thermal, pH, storage stability, and reusability. The immobilized MESAs exhibited a 2.5-fold reduction in UDP consumption, enhancing catalytic efficiency. Moreover, the immobilized MESAs demonstrated high storage and temperature stability over 21 days at 4 °C and 25 °C, outperforming their free counterparts. Reusability assays showed that the immobilized MESAs retained 78.7 % activity after 10 cycles. Utilizing fed-batch technology, the cumulative titer of curcumin 4'-O-ß-D-glucoside reached 6.51 mM (3.57 g/L) and 9.45 mM (5.18 g/L) for free AtSUSm/BsUGT2m and immobilized MESAs, respectively, over 12 h. This study demonstrates the efficiency of magnetic nickel ferrite nanoparticles in co-immobilizing enzymes, enhancing biocatalysts' catalytic efficiency, reusability, and stability.

A comprehensive review on biological funnel mechanism in lignin valorization: Pathways and enzyme dynamics.

Lignin, a significant byproduct of the paper and pulp industry, is attracting interest due to its potential utilization in biomaterial-based sectors and biofuel production. Investigating biological methods for converting lignin into valuable products is crucial for effective utilization and has recently gained growing attention. Several microorganisms effectively decomposed low molecular weight lignins, transforming them into intermediate compounds via upper and lower metabolic pathways. This review focuses on assessing bacterial metabolic pathways involved in the breakdown of lignin into aromatic compounds and their subsequent utilization by different bacteria through various metabolic pathways. Understanding these pathways is essential for developing efficient synthetic metabolic systems to valorize lignin and obtain valuable industrial aromatic chemicals. The concept of "biological funneling," which involves examining key enzymes, their interactions, and the complex metabolic pathways associated with lignin conversion, is crucial in lignin valorization. By manipulating lignin metabolic pathways and utilizing biological routes, many aromatic compounds can be synthesized within cellular factories. Although there is insufficient evidence regarding the complete metabolism of polyaromatic hydrocarbons by particular microorganisms, understanding lignin-degrading enzymes, regulatory mechanisms, and interactions among various enzyme systems is essential for optimizing lignin valorization. This review highlights recent advancements in lignin valorization, bio-funneling, multi-omics, and analytical characterization approaches for aromatic utilization. It provides up-to-date information and insights into the latest research findings and technological innovations. The review offers valuable insights into the future potential of biological routes for lignin valorization.

Green synthesis of polyphenol-grafted lignin nanoparticles and their application as sustainable anti-acne, antioxidant, and UV-blocking agents.

Acne is a persistent infectious skin condition primarily caused by Propionibacterium acne that affects 80 % of teenagers. The rise of antibiotic resistance in P. acnes has led to an increasing interest in exploring alternative antimicrobial agents. This study explored the effects of natural polyphenol (gallic and tannic acid)-grafted lignin nanoparticles on P. acnes and other pathogens causing skin infections. The process involved functionalizing lignin by grafting with gallic acid and tannic acid using laccase, followed by mechanical homogenization to synthesize lignin-gallic acid (LGAL-NPs) and lignin-tannic acid (LTAL-NPs) nanoparticles. LGAL-NPs and LTAL-NPs exhibited average low polydisperse particles of less than 60 nm and increased total phenolic content. Testing against P. acnes, S. aureus, and S. epidermidis showed that the nanoparticles had an MIC of 0.625 mg/mL. The effectiveness of LGAL-NPs and LTAL-NPs against acne-causing bacteria was attributed to their high phenolic content and nanosize. Furthermore, studies on the mechanism of action have revealed the interaction of LGAL-NPs with bacterial surfaces, destabilization of membranes, increase in ROS levels, and reduction of metabolic activity. Molecular docking results indicated that these nanoparticles effectively inhibited bacterial growth and compromised their pathogenic abilities by targeting and disrupting key virulence factors. Additionally, these nanoparticles exhibited antioxidant and UV-protecting properties, making them potentially useful in the cosmetic and pharmaceutical industries for developing skincare products. Their natural, low toxicity, cost-effective nature, and eco-friendly attributes make them a sustainable option for skincare applications.

Lignin developmental patterns and Casparian strip as apoplastic barriers: A review.

Lignin and Casparian strips are two essential components of plant cells that play critical roles in plant development regulate nutrients and water across the plants cell. Recent studies have extensively investigated lignin diversity and Casparian strip formation, providing valuable insights into plant physiology. This review presents the established lignin biosynthesis pathway, as well as the developmental patterns of lignin and Casparian strip and transcriptional network associated with Casparian strip formation. It describes the biochemical and genetic mechanisms that regulate lignin biosynthesis and deposition in different plants cell types and tissues. Additionally, the review highlights recent studies that have uncovered novel lignin biosynthesis genes and enzymatic pathways, expanding our understanding of lignin diversity. This review also discusses the developmental patterns of Casparian strip in roots and their role in regulating nutrient and water transport, focusing on recent genetic and molecular studies that have identified regulators of Casparian strip formation. Previous research has shown that lignin biosynthesis genes also play a role in Casparian strip formation, suggesting that these processes are interconnected. In conclusion, this comprehensive overview provides insights into the developmental patterns of lignin diversity and Casparian strip as apoplastic barriers. It also identifies future research directions, including the functional characterization of novel lignin biosynthesis genes and the identification of additional regulators of Casparian strip formation. Overall, this review enhances our understanding of the complex and interconnected processes that drive plant growth, pathogen defense, regulation and development.

Lignin valorization through the oxidative activity of ß-etherases: Recent advances and perspectives.

The increasing interest in lignin, a complex and abundant biopolymer, stems from its ability to produce environmentally beneficial biobased products. ß-Etherases play a crucial role by breaking down the ß-aryl ether bonds in lignin. This comprehensive review covers the latest advancements in ß-etherase-mediated lignin valorization, focusing on substrate selectivity, enzymatic oxidative activity, and engineering methods. Research on the microbial origin, protein modification, and molecular structure determination of ß-etherases has improved our understanding of their effectiveness. Furthermore, the use of these enzymes in biorefinery processes is promising for enhancing lignin breakdown and creating more valuable products. The review also discusses the challenges and future potential of ß-etherases in advancing lignin valorization for biorefinery applications that are economically viable and environmentally sustainable.

Harnessing the power of bacterial laccases for xenobiotic degradation in water: A 10-year overview.

Industrialization and population growth are leading to the production of significant amounts of sewage containing hazardous xenobiotic compounds. These compounds pose a threat to human and animal health, as well as the overall ecosystem. To combat this issue, chemical, physical, and biological techniques have been used to remove these contaminants from water bodies affected by human activity. Biotechnological methods have proven effective in utilizing microorganisms and enzymes, particularly laccases, to address this problem. Laccases possess versatile enzymatic characteristics and have shown promise in degrading different xenobiotic compounds found in municipal, industrial, and medical wastewater. Both free enzymes and crude enzyme extracts have demonstrated success in the biotransformation of these compounds. Despite these advancements, the widespread use of laccases for bioremediation and wastewater treatment faces challenges due to the complex composition, high salt concentration, and extreme pH often present in contaminated media. These factors negatively impact protein stability, recovery, and recycling processes, hindering their large-scale application. These issues can be addressed by focusing on large-scale production, resolving operation problems, and utilizing cutting-edge genetic and protein engineering techniques. Additionally, finding novel sources of laccases, understanding their biochemical properties, enhancing their catalytic activity and thermostability, and improving their production processes are crucial steps towards overcoming these limitations. By doing so, enzyme-based biological degradation processes can be improved, resulting in more efficient removal of xenobiotics from water systems. This review summarizes the latest research on bacterial laccases over the past decade. It covers the advancements in identifying their structures, characterizing their biochemical properties, exploring their modes of action, and discovering their potential applications in the biotransformation and bioremediation of xenobiotic pollutants commonly present in water sources.

Utilization of glycosyltransferases as a seamless tool for synthesis and modification of the oligosaccharides-A review.

Glycosyltransferases (GTs) catalyze the transfer of active monosaccharide donors to carbohydrates to create a wide range of oligosaccharide structures. GTs display strong regioselectivity and stereoselectivity in producing glycosidic bonds, making them extremely valuable in the in vitro synthesis of oligosaccharides. The synthesis of oligosaccharides by GTs often gives high yields; however, the enzyme activity may experience product inhibition. Additionally, the higher cost of nucleotide sugars limits the usage of GTs for oligosaccharide synthesis. In this review, we comprehensively discussed the structure and mechanism of GTs based on recent literature and the CAZY website data. To provide innovative ideas for the functional studies of GTs, we summarized several remarkable characteristics of GTs, including folding, substrate specificity, regioselectivity, donor sugar nucleotides, catalytic reversibility, and differences between GTs and GHs. In particular, we highlighted the recent advancements in multi-enzyme cascade reactions and co-immobilization of GTs, focusing on overcoming problems with product inhibition and cost issues. Finally, we presented various types of GT that have been successfully used for oligosaccharide synthesis. We concluded that there is still an opportunity for improvement in enzymatically produced oligosaccharide yield, and future research should focus on improving the yield and reducing the production cost.

Optimization of heterologous production of Bacillus ligniniphilus L1 laccase in Escherichia coli through statistical design of experiments.

Laccases are powerful multi-copper oxidoreductases that have wide applicability as "green" biocatalysts in biotechnological, bioremediation, and industrial applications. Sustainable production of large amounts of functional laccases from original sources is limited by low yields, difficulties in purification, slow growth of the organisms, and high cost of production. Harnessing the full potential of these versatile biocatalysts will require the development of efficient heterologous systems that allow high-yield, scalable, and cost-effective production. We previously cloned a temperature- and pH-stable laccase from Bacillus ligniniphilus L1 (L1-lacc) that demonstrated remarkable activity in the oxidation of lignin and delignification for bioethanol production. However, L1-lacc is limited by low enzyme yields in both the source organism and heterologous systems. Here, to improve production yields and lower the cost of production, we optimized the recombinant E. coli BL21 strain for high-level production of L1-lacc. Several culture medium components and fermentation parameters were optimized using one-factor-at-a-time (OFAT) and Plackett-Burman design (PBD) to screen for important factors that were then optimized using response surface methodology (RSM) and an orthogonal design. The optimized medium composition had compound nitrogen (15.6 g/L), glucose (21.5 g/L), K2HPO4 (0.15 g/L), MgSO4 (1 g/L), and NaCl (7.5 g/L), which allowed a 3.3-fold yield improvement while subsequent optimization of eight fermentation parameters achieved further improvements to a final volumetric activity titer of 5.94 U/mL in 24 h. This represents a 7-fold yield increase compared to the initial medium and fermentation conditions. This work presents statistically guided optimization strategies for improving heterologous production of a bacterial laccase that resulted in a high-yielding, cost-efficient production system for an enzyme with promising applications in lignin valorization, biomass processing, and generation of novel composite thermoplastics.

Evaluation of a dye-decolorizing peroxidase from Comamonas serinivorans for lignin valorization potentials.

Although dye-decolourising peroxidases (DyPs) are well-known for lignin degradation, a comprehensive understanding of their mechanism remains unclear. Therefore, studying the mechanism of lignin degradation by DyPs is necessary for industrial applications and enzyme engineering. In this study, a dye-decolourising peroxidase (CsDyP) gene from C. serinivorans was heterologously expressed and studied for its lignin degradation potential. Molecular docking analysis predicted the binding of 2, 2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), veratryl alcohol (VA), 2, 6-dimethylphenol (2, 6- DMP), guaiacol (GUA), and lignin to the substrate-binding pocket of CsDyP. Evaluation of the enzymatic properties showed that CsDyP requires pH 4.0 and 30 °C for optimal activity and has a high affinity for ABTS. In addition, CsDyP is stable over a wide range of temperatures and pH and can tolerate 5.0 mM organic solvents. Low NaCl concentrations promoted CsDyP activity. Further, CsDyP significantly reduced the chemical oxygen demand decolourised alkali lignin (AL) and milled wood lignin (MWL). CsDyP targets the ß-O-4, CO, and CC bonds linking lignin's G, S, and H units to depolymerize and produce aromatic compounds. Overall, this study delivers valuable insights into the lignin degradation mechanism of CsDyP, which can benefit its industrial applications and lignin valorization.

Characterization and 3D printing of a biodegradable polylactic acid/thermoplastic polyurethane blend with laccase-modified lignin as a nucleating agent.

Polylactic acid (PLA) has been used in fused deposition method (FDM) based 3D printing for many years. Alkali lignin is an undervalued industrial by-product that could upgrade PLA's poor mechanical properties. This work presents a biotechnological approach consisting of a partial degradation of alkali lignin using Bacillus ligniniphilus laccase (Lacc) L1 for its use as a nucleating agent in a polylactic acid/thermoplastic polyurethane (PLA/TPU) blend. Results showed that adding enzymatically modified lignin (EL) increased the elasticity modulus to a maximum of 2.5-fold than the control and conferred a maximum biodegradability rate of 15 % after 6 months under the soil burial method. Furthermore, the printing quality rendered satisfactory smooth surfaces, geometries and a tunable addition of a woody color. These findings open a new door for using laccase as a tool to upgrade lignin's properties and its use as a scaffold in manufacturing more environmentally sustainable filaments with improved mechanical properties for 3D printing.

Nano-Agrochemicals as Substitutes for Pesticides: Prospects and Risks.

This review delves into the mesmerizing technology of nano-agrochemicals, specifically pesticides and herbicides, and their potential to aid in the achievement of UN SDG 17, which aims to reduce hunger and poverty globally. The global market for conventional pesticides and herbicides is expected to reach USD 82.9 billion by 2027, growing 2.7% annually, with North America, Europe, and the Asia-Pacific region being the biggest markets. However, the extensive use of chemical pesticides has proven adverse effects on human health as well as the ecosystem. Therefore, the efficacy, mechanisms, and environmental impacts of conventional pesticides require sustainable alternatives for effective pest management. Undoubtedly, nano-agrochemicals have the potential to completely transform agriculture by increasing crop yields with reduced environmental contamination. The present review discusses the effectiveness and environmental impact of nanopesticides as promising strategies for sustainable agriculture. It provides a concise overview of green nano-agrochemical synthesis and agricultural applications, and the efficacy of nano-agrochemicals against pests including insects and weeds. Nano-agrochemical pesticides are investigated due to their unique size and exceptional performance advantages over conventional ones. Here, we have focused on the environmental risks and current state of nano-agrochemicals, emphasizing the need for further investigations. The review also draws the attention of agriculturists and stakeholders to the current trends of nanomaterial use in agriculture especially for reducing plant diseases and pests. A discussion of the pros and cons of nano-agrochemicals is paramount for their application in sustainable agriculture.

Microbial diversity and community structure in deep-sea sediments of South Indian Ocean.

Microbial communities composed of bacteria, archaea and fungi play a pivotal role in driving the biogeochemical cycles in the marine ecosystem. Despite the vastness of the South Indian Ocean, only a few studies reported the simultaneous analysis of bacterial, archaeal and fungal diversity therein, particularly archaeal and fungal communities in deep-sea environments received less attention previously. In this study, microbial diversity, community composition and dynamics in microbial community structure in eight deep-sea sediment samples collected from different sites at varying depths of the South Indian Ocean were explored using Next-Generation Sequencing. In total, 21 bacterial phyla representing 541 OTUs were identified from the eight samples, where phylum Proteobacteria was found as the most abundant bacterial phylum in five out of eight samples. Firmicutes and Chloroflexi were the dominant phyla in the rest of the three samples. In the case of archaea, uncultured species belonging to the phyla Thaumarchaeota and Euryarchaeota were the abundant taxa in all the samples. Similarly, Ascomycota and Basidiomycota were the most abundant fungal phyla present therein. In all the eight samples studied here, about 10-58% and 19-26% OTUs in archaeal and fungal communities were mapped to unclassified taxa respectively, suggesting the lack of representation in databases. Co-occurrence network analysis further revealed that bacterial communities tend to be more dynamic than archaeal and fungal communities. This study provides interesting insights into the microbial diversity, community composition and dynamics in microbial community structure in the deep-sea sediments of the South Indian Ocean.

Spatio-Temporal Modification of Lignin Biosynthesis in Plants: A Promising Strategy for Lignocellulose Improvement and Lignin Valorization.

Lignin is essential for plant growth, structural integrity, biotic/abiotic stress resistance, and water transport. Besides, lignin constitutes 10-30% of lignocellulosic biomass and is difficult to utilize for biofuel production. Over the past few decades, extensive research has uncovered numerous metabolic pathways and genes involved in lignin biosynthesis, several of which have been highlighted as the primary targets for genetic manipulation. However, direct manipulation of lignin biosynthesis is often associated with unexpected abnormalities in plant growth and development for unknown causes, thus limiting the usefulness of genetic engineering for biomass production and utilization. Recent advances in understanding the complex regulatory mechanisms of lignin biosynthesis have revealed new avenues for spatial and temporal modification of lignin in lignocellulosic plants that avoid growth abnormalities. This review explores recent work on utilizing specific transcriptional regulators to modify lignin biosynthesis at both tissue and cellular levels, focusing on using specific promoters paired with functional or regulatory genes to precisely control lignin synthesis and achieve biomass production with desired properties. Further advances in designing more appropriate promoters and other regulators will increase our capacity to modulate lignin content and structure in plants, thus setting the stage for high-value utilization of lignin in the future.

Lignin valorization: Status, challenges and opportunities.

As an abundant aromatic biopolymer, lignin has the potential to produce various chemicals, biofuels of interest through biorefinery activities and is expected to benefit the future circular economy. However, lignin valorization is hindered by a series of constraints such as heterogeneous polymeric nature, intrinsic recalcitrance, strong smell, dark colour, challenges in lignocelluloses fractionation and the presence of high bond dissociation enthalpies in its functional groups etc. Nowadays, industrial lignin is mostly combusted for electricity production and the recycling of inorganic compounds involved in the pulping process. Given the research and development on lignin valorization in recent years, important applications such as lignin-based hydrogels, surfactants, three-dimensional printing materials, electrodes and production of fine chemicals have been systematically reviewed. Finally, this review highlights the main constraints affecting industrial lignin valorization, possible solutions and future perspectives, in the light of its abundance and its potential applications reported in the scientific literature.

Harnessing microbial wealth for lignocellulose biomass valorization through secretomics: a review.

The recalcitrance of lignocellulosic biomass is a major constraint to its high-value use at industrial scale. In nature, microbes play a crucial role in biomass degradation, nutrient recycling and ecosystem functioning. Therefore, the use of microbes is an attractive way to transform biomass to produce clean energy and high-value compounds. The microbial degradation of lignocelluloses is a complex process which is dependent upon multiple secreted enzymes and their synergistic activities. The availability of the cutting edge proteomics and highly sensitive mass spectrometry tools make possible for researchers to probe the secretome of microbes and microbial consortia grown on different lignocelluloses for the identification of hydrolytic enzymes of industrial interest and their substrate-dependent expression. This review summarizes the role of secretomics in identifying enzymes involved in lignocelluloses deconstruction, the development of enzyme cocktails and the construction of synthetic microbial consortia for biomass valorization, providing our perspectives to address the current challenges.

5-Dodecanolide inhibits biofilm formation and virulence of Streptococcus pyogenes by suppressing core regulons of virulence.

This study determined the antibiofilm and antivirulence potential of 5-Dodecanolide (DD) against an exclusive human pathogen Streptococcus pyogenes. Biofilm quantification assay showed antibiofilm efficacy of DD with maximum biofilm inhibition of 85% at 225 µg/mL concentration. Efficacy of antibacterial property of DD (225 µg/mL) was confirmed by CFU analysis and Alamar blue assay. Microscopic analyses evidently confirmed micro-colony formation, biofilm thickness and surface coverage were reduced upon DD treatment. In addition, based on the results of in vitro assays, it was noted that DD impaired the synthesis of surface hydrophobicity, slime, hyaluronic acid, hemolysin and protease production. Interestingly, DD increased the autoaggregation of S. pyogenes hence, facilitated enhanced recognition of clumped bacterial cells for innate immune clearance. The results were further validated by the reduced survival of DD treated S. pyogenes in healthy human blood. Consequently, based on the qPCR analysis DD altered the expression of core regulons srv, ropB, mga and genes associated with biofilm formation and virulence such as speB, dltA, srtB, sagA and slo. Hence, the overall results of the present study for the first time revealed the antibiofilm and antivirulence property of DD against clinically important pathogen S. pyogenes and further clinical investigations are required to assess the therapeutic use of DD.

Recent Development of Extremophilic Bacteria and Their Application in Biorefinery.

The biorefining technology for biofuels and chemicals from lignocellulosic biomass has made great progress in the world. However, mobilization of laboratory research toward industrial setup needs to meet a series of criteria, including the selection of appropriate pretreatment technology, breakthrough in enzyme screening, pathway optimization, and production technology, etc. Extremophiles play an important role in biorefinery by providing novel metabolic pathways and catalytically stable/robust enzymes that are able to act as biocatalysts under harsh industrial conditions on their own. This review summarizes the potential application of thermophilic, psychrophilic alkaliphilic, acidophilic, and halophilic bacteria and extremozymes in the pretreatment, saccharification, fermentation, and lignin valorization process. Besides, the latest studies on the engineering bacteria of extremophiles using metabolic engineering and synthetic biology technologies for high-efficiency biofuel production are also introduced. Furthermore, this review explores the comprehensive application potential of extremophiles and extremozymes in biorefinery, which is partly due to their specificity and efficiency, and points out the necessity of accelerating the commercialization of extremozymes.