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United Nations sustainable development goals (SDGs) are mended for the betterment of all living species on this earth. Climate change planning consistently revolves around sustainable products derived from natural raw materials. Our recent research has specifically targeted the optimization of biocatalyst production and microorganism growth through solid-state fermentation. In this research work, we utilized Aspergillus niger [S1], isolated from a mixed vegetable pickle. Initially, batch tests were conducted, altering the concentrations of five ingredients—sucrose, molasses, yeast extract, sunflower oil, and Tween-80 to achieve maximum extracellular biocatalyst (Lipases) production. Maximum extracellular biocatalyst activity was achieved in the presence of sucrose, molasses, yeast extract, sunflower oil and tween-80 at the rate of 6.39 ± 1.73a U/mL, 2.2 ± 1.09a U/mL, 2.22 ± 0.48a U/mL, 3.06 ± 1.27a U/mL and 2 ± 0.87a U/mL respectively using different concentration of 1 g/L, 4 g/L, 0.5 g/L, 3.5% v/v and 1% v/v respectively through one factor at a time approach. Response surface methodology was employed to examine the interaction of critical medium components and their impact on biocatalyst activity. The range and level of selected independent variables were explored using the Box-Behnken experimental design. The maximum production was observed at the 6th run, reaching 13.0 U/mL by using combination of various critical medium components i.e., sucrose 3 g/L, molasses 5 g/L, yeast extract 1.5 g/L, sunflower oil 2.25% v/v, and Tween-80 0.5% v/v. Regarding the basal quantity of substrate, 10 g of mustard meal was also utilized. [ABSTRACT FROM AUTHOR]

Biofuel cells have recently gained popularity as a green and renewable energy source. Biofuel cells are unique devices of energy and are capable of converting the stored chemical energy from waste materials such as pollutants, organics and wastewater into reliable, renewable, pollution-free energy sources through the action of biocatalysts such as various microorganisms and enzymes. It is a promising technological device to treat waste to compensate for global warming and the energy crisis through the green energy production process. Due to their unique properties, various potential biocatalysts are attracting researchers to apply them to various microbial biofuel cells for improving electricity and power. Recent research in biofuel cells is focusing on the exploitation of different biocatalysts and how they are enhancing power generation for various applications in the field of environmental technology, and biomedical fields such as implantable devices, testing kits, and biosensors. This review focusing the importance of microbial fuel cells (MFCs) and enzymatic fuel cells (ECFs) and role of different types of biocatalysts and their mechanisms for improving biofuel cell efficiency gathered from recent reports. Finally, its multifaceted applications with special emphasis on environmental technology and biomedical field will be described, along with future perspectives. [ABSTRACT FROM AUTHOR]

Biodiesel generated from oils and fats composed of fatty acid alkyl esters is a potential substitution for fossil fuels, gaining attention as the demand for sustainable energy grows. Enzymatic transesterification has emerged as a promising method for biodiesel production due to the low energy required, easy glycerol recovery and compatibility with various feedstocks. This method also offers high specificity and operates under mild reaction conditions. However, limitations such as enzyme production cost, low product yield, and low stability under harsh conditions, have hindered the progress of biocatalysis. Protein engineering has emerged as an important strategy to overcome these limitations, particularly through rational design. Rational design approaches are advantageous in lipase engineering, due to accessible experimental tools and existing knowledge of lipase structure and function. Site-directed mutagenesis has been applied to improve stability, substrate specificity, methanol tolerance, and catalytic efficiency of lipase by introducing molecular interactions like hydrogen bonds and disulfide bridges as well as improved lid flexibility by mutations at the lid or lid swapping. This targeted approach allows for the precise modification of amino acid residues, optimizing lipase for better performance, which is crucial for efficient biodiesel production. [ABSTRACT FROM AUTHOR]

The imperative of transforming waste materials into valuable nanomaterials via ecological recycling has emerged as a pivotal avenue for environmental stewardship. This research contributes to the "greening" of global chemical processes by introducing a magnetic biocatalyst derived from red mud waste. Emphasizing the use of glutamic acid as the second most effective step in obtaining a green catalyst is a key focus of this work. Leveraging cost-effective materials such as FeSO4, amino acid, and Fe2O3 isolated from red mud enhances the economic viability of the synthesized catalyst. Characterization of the newly developed nano-magnetic bio-organocatalysts was conducted using advanced spectroscopic techniques, including Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), field emission scanning electron microscopy (FE-SEM), Brunauer-Emmett-Teller (BET), energy-dispersive X-ray spectroscopy (EDX), mapping, thermogravimetric analysis (TGA), and vibrating-sample magnetometers (VSM). The catalytic activity of Fe3O4@SiO2@(CH2)3@Gl was examined in the one-pot synthesis of polyhydroquinolines, showcasing short reaction times, high efficiency, ease of catalyst separation, and the potential for catalyst recycling as salient features of this work. This study pioneers the utilization of red mud waste for eco-friendly nanomaterial synthesis and underscores the economic and environmental significance of incorporating glutamic acid as a crucial element in the catalyst synthesis process. [ABSTRACT FROM AUTHOR]

AbstractImmobilized Aspergillus ficuum tannase on amino-functionalized multiwalled carbon nanotubes (A-MWCNT) was assembled through glutaraldehyde-mediated covalent coupling to produce a stable biocatalyst nanocomposite. The effective binding of tannase on the surface of A-MWCNT was evaluated and authenticated by spectroscopic signature signals and morphological differences, before and after enzyme coupling. Both free- and immobilized tannase showed optimal catalytic activities at pH 5.0 and 35 °C, with the immobilized tannase exhibiting enhanced thermostability compared to the soluble enzyme. The immobilized tannase preparation was also found to be reusable up to five cycles, with 66% of initial enzyme activity retained thereafter. The enzyme-carbon nanotube composite preparation allows for bioconversion to be accomplished in a bioreactor with a smaller footprint. [ABSTRACT FROM AUTHOR]

Humin-sulfuric acid (Humin-SO3H) as a novel efficient biobased sulfonic acid was easily prepared by adding chlorosulfuric acid (ClSO3H) to Humin and characterized by potentiometric titration and FT-IR spectrum. Humin-SO3H is an eco-friendly, heterogeneous biobased, and efficient catalyst for Paal-Knorr and Clauson-Kaas pyrrole synthesis. The catalyst is easily recovered by simple filtration and has excellent turnover efficiency even after 4 cycles. Besides, due to the clearance of the biocatalyst away from the reaction media, the desired highly pure products can be achieved in high to excellent yields. Due to high water dispersibility, Humin-SO3H can be utilized as a highly efficient green catalyst for pyrrole synthesis. [ABSTRACT FROM AUTHOR]

In this research, we endeavour to demonstrate the potential of Aqueous Extract of Dillenia indica (AEDI) pseudosepals in catalyzing tetrahydrobenzo[b]pyran and spirooxindole derivatives, thereby paving the way for greener and more sustainable chemical synthetic strategies. The reactions proceed smoothly with AEDI as the catalyst in water at room temperature to afford high to near quantitative yields in a short duration of 15–45 minutes, making it a green and environmentally friendly alternative to existing protocols. This synthetic pathway satisfies several green chemistry principles such as avoiding the use of any toxic or hazardous metal catalyst and other external additives/promoters, the use of a biodegradable catalyst obtained from natural resources, auxiliary solvent conditions, and reusability of the catalyst. The protocol reported here offers remarkable attributes like wide substrate scope, high to near quantitative yields of products and the scale up viability along with ecological safety, straightforward work‐up procedure and excellent values of green chemistry metrics as compared to other reported approaches. [ABSTRACT FROM AUTHOR]

Abstract The imperative of transforming waste materials into valuable nanomaterials via ecological recycling has emerged as a pivotal avenue for environmental stewardship. This research contributes to the “greening” of global chemical processes by introducing a magnetic biocatalyst derived from red mud waste. Emphasizing the use of glutamic acid as the second most effective step in obtaining a green catalyst is a key focus of this work. Leveraging cost-effective materials such as FeSO4, amino acid, and Fe2O3 isolated from red mud enhances the economic viability of the synthesized catalyst. Characterization of the newly developed nano-magnetic bio-organocatalysts was conducted using advanced spectroscopic techniques, including Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), field emission scanning electron microscopy (FE-SEM), Brunauer-Emmett-Teller (BET), energy-dispersive X-ray spectroscopy (EDX), mapping, thermogravimetric analysis (TGA), and vibrating-sample magnetometers (VSM). The catalytic activity of Fe3O4@SiO2@(CH2)3@Gl was examined in the one-pot synthesis of polyhydroquinolines, showcasing short reaction times, high efficiency, ease of catalyst separation, and the potential for catalyst recycling as salient features of this work. This study pioneers the utilization of red mud waste for eco-friendly nanomaterial synthesis and underscores the economic and environmental significance of incorporating glutamic acid as a crucial element in the catalyst synthesis process.

The utilization of hydrolytic enzymes in various industrial processes worldwide has gained more attention than chemical catalysts due to the high selectivity of enzymes, their ease of control, and their negligible environmental impact, as they produce very small amounts of byproducts. Xylanase is one such enzyme that catalyzes the breakdown of the β-1,4 linkage of xylan, the second most abundant renewable heteropolysaccharide and hemicellulosic constituent of the plant cell wall. Naturally, xylanase can be obtained from various sources such as mollusks, insects, plants, animals, and various microorganisms (bacteria, fungi, yeast, and algae). The utilization of xylanase could greatly improve the overall economics of processing lignocellulosic materials for the generation of monosaccharides, liquid fuels, and chemicals. Microbial xylanase is suitable for applications in food and feed, paper and pulp, textile, pharmaceutical, and biorefining industries. It has gained global attention due to its substrate specificities, biochemical properties, and various biotechnological applications. This review focuses on xylanase production, sources, fermentation processes, modes of action, purification methods, and applications in various industries.

Abstract Humin-sulfuric acid (Humin-SO3H) as a novel efficient biobased sulfonic acid was easily prepared by adding chlorosulfuric acid (ClSO3H) to Humin and characterized by potentiometric titration and FT-IR spectrum. Humin-SO3H is an eco-friendly, heterogeneous biobased, and efficient catalyst for Paal-Knorr and Clauson-Kaas pyrrole synthesis. The catalyst is easily recovered by simple filtration and has excellent turnover efficiency even after 4 cycles. Besides, due to the clearance of the biocatalyst away from the reaction media, the desired highly pure products can be achieved in high to excellent yields. Due to high water dispersibility, Humin-SO3H can be utilized as a highly efficient green catalyst for pyrrole synthesis.

Abstract A novel approach for the synthesis of 1,3,4-oxa(thia)diazole aryl thioethers through a biocatalytic strategy has been introduced. By leveraging Myceliophthora thermophila laccase (Novozym 51003) as a catalyst, catechol undergoes oxidation to ortho-quinone, facilitating subsequent 1,4-thia-Michael addition reactions. The method offers efficiency and mild reaction conditions, demonstrating promise for sustainable synthesis pathways in organic chemistry. Using this approach, 13 new derivatives of 2,5-disubstituted-1,3,4-oxa(thia)diazole aryl thioethers, with a yield of 46–94%, were synthesized.

Bioelectroremediation technology (BERT) is a new age greener technology which is currently been heavily studied for treatment of persistent industrial effluents such as polycyclic aromatic hydrocarbons (PAHs), perchloroethylene (PCE), perchlorate, nitrate and petroleum hydrocarbon (PHs) along with simultaneous generation of bioenergy. The focus of this review paper is on these industrial effluents because many of these effluents are toxic in nature and through contaminated water, soil or sediment enter the food chain and start to bioaccumulate thereby entering living organisms and causing severe fatal diseases. While PAHs and nitrates are major contaminant of both water and soil but their removal efficiency through BERT is much more in water sample than from soil samples, studies have shown that perchlorate and nitrate are usually co-contaminants and perchlorate, PCE and PHs are much more prevalent groundwater contaminant with good removal efficiency of these contaminants and simultaneous bioelectricity generation through BERT. Therefore, this review paper focus on role of microbial community structure as a biocatalyst in BERT along with a in-depth review of bioelectroremediation process for industrial effluent treatment involved in removing diverse pollutants integrated with energy generation from fundamentals, challenges, and future prospective dimensions. [ABSTRACT FROM AUTHOR]

Lipases are enzymes that hydrolyze long-chain carboxylic esters, and in the presence of organic solvents, they catalyze organic synthesis reactions. However, the use of solvents in these processes often results in enzyme denaturation, leading to a reduction in enzymatic activity. Consequently, there is significant interest in identifying new lipases that are resistant to denaturing conditions, with extremozymes emerging as promising candidates for this purpose. Lip7, a lipase from Geobacillus sp. ID17, a thermophilic microorganism isolated from Deception Island, Antarctica, was recombinantly expressed in E. coli C41 (DE3) in functional soluble form. Its purification was achieved with 96% purity and 23% yield. Enzymatic characterization revealed Lip7 to be a thermo-alkaline enzyme, reaching a maximum rate of 3350 U mg−1 at 50 °C and pH 11.0, using p-nitrophenyl laurate substrate. Notably, its kinetics displayed a sigmoidal behavior, with a higher kinetic efficiency (kcat/Km) for substrates of 12-carbon atom chain. In terms of thermal stability, Lip7 demonstrates stability up to 60 °C at pH 8.0 and up to 50 °C at pH 11.0. Remarkably, it showed high stability in the presence of organic solvents, and under certain conditions even exhibited enzymatic activation, reaching up to 2.5-fold and 1.35-fold after incubation in 50% v/v ethanol and 70% v/v isopropanol, respectively. Lip7 represents one of the first lipases from the bacterial subfamily I.5 and genus Geobacillus with activity and stability at pH 11.0. Its compatibility with organic solvents makes it a compelling candidate for future research in biocatalysis and various biotechnological applications. [ABSTRACT FROM AUTHOR]

Hydrogen (H2), a renewable energy source with a high energy density and a reputation for being environmentally benign, is being lauded for its potential in various future applications. In the present context, the catalytic methanolysis of sodium borohydride (NaBH4) is of considerable importance due to its provision of a pathway for the efficient production of hydrogen gas (H2). The main aim of this research attempt was to assess the viability of utilizing refuse defatted sumac seeds as an unusual precursor in microwave-assisted K2CO3 activation to produce a biocatalyst. The primary objective that motivated the synthesis of the biocatalyst was to facilitate the generation of hydrogen via the catalytic methanolysis of NaBH4. With the aim of developing a biocatalyst characterized by enhanced catalytic performance, we conducted an exhaustive investigation of a wide range of experimental parameters. The activation agent-to-sample ratio (IR), impregnation time, microwave power, and irradiation time were among these parameters. Significantly enhanced in catalytic activity, the biocatalyst produced under particular conditions achieved a peak hydrogen production efficiency of 10,941 mL min− 1 g.cat− 1. In particular, it was determined that the ideal conditions were as follows: 0.5 IR, 24 h of impregnation, 500 W of microwave power, and 10 min of irradiation. This novel strategy not only demonstrates the impressive potential of eco-friendly biocatalysts, but also positions them as a viable alternative material for the sustainable production of hydrogen via NaBH4 methanolysis. Three significant parameters contribute to the value and renewability of this study. The first is that waste is used as the primary material; the second is that the activator is less hazardous than other activators; and the third is that microwave activation is a green chemistry technique. [ABSTRACT FROM AUTHOR]

The utilization of hydrolytic enzymes in various industrial processes worldwide has gained more attention than chemical catalysts due to the high selectivity of enzymes, their ease of control, and their negligible environmental impact, as they produce very small amounts of byproducts. Xylanase is one such enzyme that catalyzes the breakdown of the β-1,4 linkage of xylan, the second most abundant renewable heteropolysaccharide and hemicellulosic constituent of the plant cell wall. Naturally, xylanase can be obtained from various sources such as mollusks, insects, plants, animals, and various microorganisms (bacteria, fungi, yeast, and algae). The utilization of xylanase could greatly improve the overall economics of processing lignocellulosic materials for the generation of monosaccharides, liquid fuels, and chemicals. Microbial xylanase is suitable for applications in food and feed, paper and pulp, textile, pharmaceutical, and biorefining industries. It has gained global attention due to its substrate specificities, biochemical properties, and various biotechnological applications. This review focuses on xylanase production, sources, fermentation processes, modes of action, purification methods, and applications in various industries. [ABSTRACT FROM AUTHOR]

This study characterized cytochrome P450 enzyme CYP154C7 from Streptomyces sp. PAMC26508, emphasizing its capability to hydroxylate steroids, especially at the 16α-position. The enzymatic assay of CYP154C7 demonstrated effective conversion across a pH range of 7.2–7.6, with optimal activity at 30 °C in the Pdx/PdR plus NADH system. Kinetic analysis on most converted steroids (androstenedione and adrenosterone) was performed which shows a greater affinity for androstenedione (Km, 11.06 ± 1.903 μM; Vmax, 0.0062 ± 0.0002 sec−1) compared to adrenosterone (Km, 34.50 ± 6.2 μM; Vmax, 0.0119 ± 0.0007 sec−1). A whole-cell system in Escherichia coli, overexpressing recombinant CYP154C7, achieved substantial conversion for steroids, indicating that CYP154C7 can also be used as a potential whole-cell biocatalyst. To gain structural insights, homology models of CYP154C7 and its homologs were constructed using CYP154C5 (PDB ID: 6TO2), refined, validated, and used for docking studies. Comparative docking analysis suggests that lysine (K236) in the active site and tyrosine (Y197) in the substrate access channel of CYP154C7 are crucial for substrate selectivity and catalytic efficiency. This study suggests that CYP154C7 could be a promising candidate for developing modified steroids, providing valuable insights for protein engineering to design commercially useful CYP steroid hydroxylases with diverse substrate specificities.

Abstract Biorefineries require low-cost production processes, low waste generation and equipment that can be used not only for a single process, but for the manufacture of several products. In this context, in this research a continuous 3D printing microbioreactor coupled to an Arduino-controlled automatic feeding system was developed for the intensification of the ethanol production process from xylose/xylulose (3:1), using a new biocatalyst containing the co-culture of Scheffersomyces stipitis and Saccharomyces cerevisiae (50/50). Initially, batch fermentations of monocultures of S. cerevisiae and S. stipitis and co-culture were carried out. Subsequently, the immobilized co-culture was used as a biocatalyst in continuous fermentations using the developed microreactor. Fermentations carried out in the microbioreactor presented a 2-fold increase in the ethanol concentration and a 3-fold increase in productivity when compared to monocultures. The microbioreactor developed proved to be efficient and can be extended for other bioproducts production. This approach proved to be a promising alternative for the use of the hemicellulose fraction of biomasses without the need to use modified strains.

Here, we developed magnetically recoverable biocatalysts based on magnetite nanoparticles coated with an ultra-thin layer (about 0.9 nm) of chitosan (CS) ionically cross-linked by sodium tripolyphosphate (TPP). Excessive CS amounts were removed by multiple washings combined with magnetic separation. Glucose oxidase (GOx) was attached to the magnetic support via the interaction with N-hydroxysuccinimide (NHS) in the presence of carbodiimide (EDC) leading to a covalent amide bond. These steps result in the formation of the biocatalyst for D-glucose oxidation to D-gluconic acid to be used in the preparation of pharmaceuticals due to the benign character of the biocatalyst components. To choose the catalyst with the best catalytic performance, the amounts of CS, TPP, NHS, EDC, and GOx were varied. The optimal biocatalyst allowed for 100% relative catalytic activity. The immobilization of GOx and the magnetic character of the support prevents GOx and biocatalyst loss and allows for repeated use. [ABSTRACT FROM AUTHOR]

Nitrilases are the enzymes that catalyze the hydrolysis of nitriles to corresponding carboxylic acid and ammonia. They are broadly categorized into aromatic, aliphatic, and arylacetonitrilases based on their substrate specificity. Most of the studies pertaining to these enzymes in the literature have focused on aromatic and aliphatic nitrilases. However, arylacetonitrilases have attracted the attention of academia and industry in the last several years due to their aryl specificity and enantioselectivity. They have emerged as interesting biocatalytic tools in green chemistry to synthesize useful aryl acids such as mandelic acid and derivatives of phenylacetic acid. The aim of the present review is to collate information on the arylacetonitrilases and their catalytic properties including enantioselectivity and potential applications in organic synthesis. [ABSTRACT FROM AUTHOR]

In recent years, biocatalysts have emerged as crucial tool in organic synthesis, particularly for the production of drug intermediates and precursors, e.g., the synthesis of hydroxamic acids. Traditionally, hydroxamic acids were synthesized using organic chemistry methods. However, with the growing emphasis on sustainable and environment‐friendly practices, the chemical industry has increasingly turned towards green synthesis approaches. The significance of hydroxamic acids in medicinal chemistry has also contributed to the changing trends. Following the approval of certain hydroxamic acids as histone deacetylase (HDAC) inhibitors for cancer treatment by the Food and Drug Administration (US‐FDA), there has been a renewed focus on their synthesis and the development of derivatives with improved properties. As an alternative route, amidases have emerged as promising biocatalysts for hydroxamic acid synthesis through their acyltransferase activity. Recent advancements in the synthesis approaches for hydroxamic acids are reviewed. The biocatalytic routes are explored, emphasizing the use of amidases and their acyltransferase activity. The scope and potential applications of this chemoenzymatic approach in synthesizing various hydroxamic acids and their derivatives are discussed. Such advancements have the potential to revolutionize the production of these important compounds, making the synthesis process more sustainable, efficient, and economically viable. [ABSTRACT FROM AUTHOR]

This study unveils an innovative method for synthesizing coumarin S-glycosides, employing original biocatalysts able to graft diverse carbohydrate structures onto 7-mercapto-4-methyl-coumarin in one-pot reactions. The fluorescence properties of the generated thio-derivatives were assessed, providing valuable insights into their potential applications in biological imaging or sensing. In addition, the synthesized compounds exhibited no cytotoxicity across various human cell lines. This research presents a promising avenue for the development of coumarin S-glycosides, paving the way for their application in diverse biomedical research areas. [ABSTRACT FROM AUTHOR]

The review summarizes and analyzes information regarding the effect of nanoparticles (NPs) of metals, metal oxides and carbon on the biofilm formation and mature biofilms of microorganisms. The viability of individual microbial cells, including direct disruption of cell surface structures and oxidative stress associated with the formation of reactive oxygen species (ROS), as well as the effect on the production of the exopolymer matrix and the quorum sensing system are considered as the mechanisms of NPs action on biofilms. The effects of silver NPs, gold NPs, some metal oxides, and carbon nanomaterials on microbial biofilms have been described in more detail. The effects of metal and carbon NPs on microbial biofilms are compared. Both antibiofilm and probiofilm effects of NPs are noted, depending on their nature, and the prospect of their use as antimicrobial agents and carriers for the production of microbial biofilms of biotechnological significance are considered. [ABSTRACT FROM AUTHOR]

In this study, a packed-bed reactor was used to produce biodiesel from disposed soybean oil using a lipase-nanoparticle bio composite catalyst. During the transesterification process of the ‘disposed of/used soybean oil’, different nano catalysts were employed such as nanoparticles of Ni-doped ZnO, Fe3O4, Alkylcelite, Poly-acrylonitrile fibres and Poly-acrylonitrile nanofibrous membrane and they were abbreviated as CI, CII, CIII, CIV and CIV respectively. In each case of biodiesel production, there were two levels of process parameters like flow velocity (such as 0.25 mL/min-1.25 mL/min) and the reaction time (20 and 100 h) were considered for analyses. From the derived biofuel, the biodiesel blends were prepared as B50 (50% diesel and 50% biodiesel) and B75 (25% diesel and 75% biodiesel). The synthesis of biofuel results, in the biodiesel conversion of cepacia lipase with Poly-acrylonitrile nanofibrous membrane nanoparticles being recorded at about 85% at a 1.25 mL/min flow rate, which is the maximum biodiesel conversion among five grades. The shortlisted biodiesel performances were analyzed by varying the engine speed, grade and kind of biodiesel, The observed results were analyzed. The B50CIV and B75CIV blends recorded the maximum BSFC at 1800 rpm engine speed. CO2 emission by diesel is about 2.3 vol% was recorded. It is the highest value compared to biodiesel blends (B50 and B75). The emission of NOx with the B50CII blend was 220 ppm at the engine speed of 1800 rpm. Based on the experimental results, B50CIV serves affordable fuel and is recommended among those tested in this investigation for CI engines.

Specific stereoisomer is paramount as it is vital for optimizing drug efficacy and safety. The quest for the isolation of desired stereoisomer of active pharmaceutical ingredients or key intermediates drives innovation in drug synthetic and biocatalytic methods. Chiral phosphoramidate is an important building block for the synthesis of antiviral drugs such as remdesivir and sofosbuvir. Given the clinical potency of the (Sp)-diastereomer of the drugs, an enzyme capable of completely hydrolyzing the (Rp)-diastereomer is needed to achieve the purified diastereomers via biocatalytic reaction. In this study, protein engineering of phosphotriesterase (PTE) was aimed to improve the specificity. Employing rational design and site-directed mutagenesis, we generated a small library comprising 24 variants for activity screening. Notably, W131M and I106A/W131M variants demonstrated successful preparation of pure (Sp)-diastereomer of remdesivir and sofosbuvir precursors within a remarkably short hydrolysis time (

Phosphorus (P) is essential for biological systems, playing a pivotal role in energy metabolism and forming crucial structural components of DNA and RNA. Yet its bioavailable forms are scarce. Phytate, a major form of stored phosphorus in cereals and soils, is poorly bioavailable due to its complex structure. Phytases, enzymes that hydrolyze phytate to release useable phosphorus, are vital in overcoming this limitation and have significant biotechnological applications. This study employed novel method to isolate and characterize bacterial strains capable of metabolizing phytate as the sole carbon and phosphorus source from the Andes mountains soils. Ten strains from the genera Klebsiella and Chryseobacterium were isolated, with Chryseobacterium sp. CP-77 and Klebsiella pneumoniae CP-84 showing specific activities of 3.5 ± 0.4 nkat/mg and 40.8 ± 5 nkat/mg, respectively. Genomic sequencing revealed significant genetic diversity, suggesting CP-77 may represent a novel Chryseobacterium species. A fosmid library screening identified several phytase genes, including a 3-phytase in CP-77 and a glucose 1-phosphatase and 3-phytase in CP-84. Phylogenetic analysis confirmed the novelty of these enzymes. These findings highlight the potential of phytase-producing bacteria in sustainable agriculture by enhancing phosphorus bioavailability, reducing reliance on synthetic fertilizers, and contributing to environmental management. This study expands our biotechnological toolkit for microbial phosphorus management and underscores the importance of exploring poorly characterized environments for novel microbial functions. The integration of direct cultivation with metagenomic screening offers robust approaches for discovering microbial biocatalysts, promoting sustainable agricultural practices, and advancing environmental conservation.

This study reports the genome sequence data of a novel Stenotrophomonas sepilia Alg010 strain isolated from Sargassum seaweed waste accumulated on the coastline of Barbados. The genome sequence data was obtained via sequencing of the genomic DNA of this isolate with Illumina NextSeq2000 platform and paired-end library preparation protocol. The resulting reads were assembled with the SPAdes Genome Assembler (ver 3.15.4) and annotated with the DDBJ Fast Annotation and Submission Tool. The genome size of this novel isolate was recorded as 4,515,447 bp with a coverage of 270×, a GC content of 66.6 % and a gap ratio of 0.027 %. The lengths of the longest and the N50 contigs were estimated as 246,749 bp and 81,982 bp, respectively. The genome contains 2 rRNA, 66 tRNA, 2 CRISPR, 86 contigs and 4024 CDSs (coding sequences) with a coding ratio of 88.9 %. The annotation of the CDSs for COG (cluster of orthologous groups) and for subsystem features indicated that the metabolism and the amino acids and derivatives were the most dominant categories, respectively. The annotation of the genome via dbCAN3 server for carbohydrate-active genes revealed 98 genes encoding the six functional classes of carbohydrate-active enzymes. The genome sequence data is available in NCBI GenBank with the accession number BTRJ00000000.

This study explores the use of muscovite mica combined with Fe3O4 nanoparticles to create a low-cost bio-composite. The composite was analyzed using XRD, pHPZC, FTIR, SEM, EDX, XRF, and BET. The investigation of adsorption parameters unveiled an adsorption efficacy of 97 % after 30 min with a ratio of 1 g/L. The experimental data aligned well with the pseudo-second-order equation and Temkin model, indicating a maximum adsorption capacity of 51.17 mg/g. Fixed-bed column studies demonstrated decreased efficiency with increased initial concentration, flow rate, and bed depth, with optimal performance at pH=8 and accurate representation by the Thomas model. The maximum capacity is achieved 34.69 mg/g when the bed depth is 0.5 cm, the flow rate is 2.5 mL/min, and the inlet concentration is 50 mg/L. The composite's degradation efficacy was evaluated under sunlight-activated photocatalysis, achieving over 95% degradation of MB within 90 minutes using 3 mL H2O2, an initial MB concentration of 40 mg/L, and only a catalyst quantity of 0.25 g/L. Degradation data were well-fitted by the first-order kinetic model. The study highlights the remarkable efficiency and swiftness of the degradation process compared to adsorption.

Nanotechnology gained a lot of attention nowadays because of its enormous applications. Due to the need for developing new synthetic methods, various physical, chemical, and biological methods are used in the synthesis of nanoparticles. From an environmental point of view, green synthetic methods provide advantages over conventional chemical and physical methods. Among green methods, biosynthesis is a widely emerging method for the synthesis of nanoparticles because it shows prodigious advantages such as low toxicity, simplicity, cheapness, use of less energy, and rapid. Biosynthesis is a highly efficient method for the fabrication of nanoparticles. Palladium nanoparticles are widely used in different areas of applications such as catalysis, medicine, biomedical applications, cosmetics, pharmaceutical products, and electronic components. This review includes recent catalytic advancements in organic transformations using biogenically synthesized palladium nanoparticles and their applications. This review highlights the potential of this field for researchers. Graphical presentation of biosynthesis, characterization, and applications of palladium nanoparticles [ABSTRACT FROM AUTHOR]

Currently, industry in all its forms is vital for the human population because it provides the services and goods necessary to live. However, this process also pollutes soils and rivers. This research provides an environmentally friendly solution for the generation of electrical energy and the bioremediation of heavy metals such as arsenic, iron, and copper present in river waters used to irrigate farmers' crops. This research used single-chamber microbial fuel cells with activated carbon and zinc electrodes as anodes and cathodes, respectively, and farmers' irrigation water contaminated with mining waste as substrate. Pseudomonas stutzeri was used as a biocatalyst due to its ability to proliferate at temperatures between 4 and 44 °C—at which the waters that feed irrigated rivers pass on their way to the sea—managing to generate peaks of electric current and voltage of 4.35 mA and 0.91 V on the sixth day, which operated with an electrical conductivity of 222 mS/cm and a pH of 6.74. Likewise, the parameters of nitrogen, total organic carbon, carbon lost on the ignition, dissolved organic carbon, and chemical oxygen demand were reduced by 51.19%, 79.92%, 64.95%, 79.89%, 79.93%, and 86.46%. At the same time, iron, copper, and arsenic values decreased by 84.625, 14.533, and 90.831%, respectively. The internal resistance values shown were 26.355 ± 4.528 Ω with a power density of 422.054 mW/cm2 with a current density of 5.766 A/cm2. This research gives society, governments, and private companies an economical and easily scalable prototype capable of simultaneously generating electrical energy and removing heavy metals. [ABSTRACT FROM AUTHOR]

Nitrocellulose accumulated in sludge accumulators does not undergo any changes and remains explosive for decades but it can be used as initial recourse for H 2 and nanocarbon production through biogas. Anaerobic biotransformation of waste with a nitrocellulose content of about 75% with native microflora, consortia of mesophilic or thermophilic microorganisms from industrial bioreactors under various volume loading of microorganisms and temperature conditions has been studied. Stimulation by an additional source of biogenic elements and the development of native microflora made it possible to reduce the concentration of nitrocellulose by 44% at 35 °C in 100 days. With a biocatalyst volume loading of 30% at 35 °C with mesophilic biocatalyst 39% of nitrocellulose (with 50% initial volume loading) was conversed to biogas, at 55 °C with thermophilic biocatalyst-99%. The rate constant of decomposition of nitrocellulose using a thermophilic biocatalyst was 0.0248 day−1, while the half–life of nitrocellulose was 28 days. [ABSTRACT FROM AUTHOR]

The assessment of anaerobic biotransformation in thermophilic mode (55 °C) of agricultural waste was carried out. It has been established that organic wastes (wheat distillery vinasse, cow manure and chicken manure) have a great potential for producing biogas with a high content of methane and carbon dioxide with a low content of impurities. Biogas can be recommended as a raw material for hydrogen production. With the ratio of components in the composition of the mixed substrate of distillery vinasse, cow manure and chicken manure - 6: 3: 1 for 21–29 days of anaerobic digestion, the best indicators of the efficiency of methanogenesis for methane (61–63%) and biogas (70–73%) were provided, the share of methane in composition of biogas was 61%. With the biotransformation of alone vinasse, the nitrogen mineralization efficiency (58–67%) was lower than when using a mixture of organic waste (63–69%). From the point of view of obtaining the maximum amount of biogas, it is advisable to add a carbonate buffer or limestone flour (9% wt.) to the substrate to shift the pH of the working solution towards slightly alkaline values. From the point of view of the accumulation of free phosphates in the final solution, the use of a carbonate buffer is more preferable. The anaerobically treated solid sludge remaining after biogas production, as well as liquid effluents (anaerobically treated effluents) can be considered as potential organic and biogenic fertilizers or their components. [ABSTRACT FROM AUTHOR]

Biosilica, synthesized annually only by diatoms, is almost 1000 times more abundant than industrial silica. Biosilicification occurs at a high rate, although the concentration of silicic acid in natural waters is ~100 μM. It occurs in neutral aqueous solutions, at ambient temperature, and under the control of proteins that determine the formation of hierarchically organized structures. Using diatoms as an example, the fundamental differences between biosilicification and traditional sol–gel technology, which is performed with the addition of acid/alkali, organic solvents and heating, have been identified. The conditions are harsh for the biomaterial, as they cause protein denaturation and cell death. Numerous attempts are being made to bring sol–gel technology closer to biomineralization processes. Biomimetic synthesis must be conducted at physiological pH, room temperature, and without the addition of organic solvents. To date, significant progress has been made in approaching these requirements. The review presents a critical analysis of the approaches proposed to date for the silicification of biomacromolecules and cells, the formation of bionanocomposites with controlled structure, porosity, and functionality determined by the biomaterial. They demonstrated the broad capabilities and prospects of biomimetic methods for creating optical and photonic materials, adsorbents, catalysts and biocatalysts, sensors and biosensors, and biomaterials for biomedicine. [ABSTRACT FROM AUTHOR]

This study investigated the use of immobilized lipase in SBA‐15 and pore‐expanded SBA‐15 surface modified with tin, denoted as SnS23B (mean pore size of 21.6 nm) and SnS8B (with mean pore size of 9.6 nm), respectively, to produce ethyl esters. The effects of various reaction parameters, including biocatalyst type, oil (refined and degummed soybean oil), water addition, oil‐to‐ethanol molar ratio, immobilized lipase concentration, agitation speed, reaction temperature, and glycerol addition, were examined. The optimal conditions were found to be the use of SnS23B as the biocatalyst, degummed soybean oil as the substrate, 1% (w/w oil) water, 1:3 oil‐to‐ethanol molar ratio, 5% (w/w oil) immobilized lipase, 800 rpm agitation speed, and 25°C reaction temperature. The presence of glycerol negatively impacted the reaction. Under the optimal conditions, the mass percent of ethyl ester obtained was 98.2% ± 0.16. The immobilized lipase showed stability, as no lipase activity was detected upon removing the biocatalyst from the reaction. However, the biocatalyst lost 50% of its activity after 10 successive reactions, likely due to thermal deactivation and lipase inhibition caused be the adsorption of glycerol and other chemical species. Attenuated total reflectance analysis supported this hypothesis. [ABSTRACT FROM AUTHOR]

It has long been known that the textile industry generates a massive amount of synthetic waste across the globe. Dye-containing wastewater is carcinogenic, mutagenic, recalcitrant, and xenobiotic. Several techniques have been developed for textile wastewater treatment. Most often, especially for dye-containing synthetic waste, bioremediation has now become one of the emerging techniques. Bioreactor, a common apparatus, whenever possible, may operate either continuously or in batches; has been extensively used for carrying out the hardest-to-meet biological reactions. The objective of this review is to emphasize a brief description of different bioreactors' performance, their features, and shortcoming. Special emphasis has been laid out on Membrane Bioreactor, Fluidized Bed Bioreactor, Moving Bed Bioreactor, Packed Bed Bioreactor, Airlift Bioreactor, Stirred Tank Bioreactor, Fixed Bed Bioreactor, and Rotating Biological Contactor. The key findings of each bioreactor's dye degradation performance have been reviewed. A brief discussion about recent trends in dye wastewater treatment has been depicted and based on the above facts future outlook is critically highlighted. A techno-economic assessment of bioremediation technology emphasizes its applicability for industrial scale. The review is expected to be beneficial to readers who are dealing with bioprocess, hybrid bioreactors, and designing bioreactors at a laboratory, pilot plant, and even on an industrial scale for the treatment of real textile waste. However, the selection criterion of a suitable bioreactor has relied on bioprocess engineering and economics. New technological advancements in the bioreactor have been discussed and Microbioreactor seems as a future outlook toward dye degradation. [ABSTRACT FROM AUTHOR]

The goal of the current study is to propose and study an innovative method in synthesizing biocatalyst within a microfluidic reactor and later use it in the esterification of β-sitosterol. A droplet microreactor was specially designed and fabricated using soft-lithography technique and was used for formulation of silica nanoparticles. Sol-gel reaction method was adapted in the microreactor to produce nanoparticles which were used as the support for lipase from Rhizomucor miehei. Another microfluidics reactor was also designed and fabricated for the immobilization of the Lipase on the silica nanoparticles through a physical adsorption technique producing a biocatalyst. The catalytic efficacy of the biocatalyst was next evaluated by esterifying β-sitosterol (the main component of phytosterol) at two different catalyst loadings and comparing it to free lipase under the same experimental parameters. Samples were taken periodically and diluted with n-hexane before injecting them into gas chromatography for analysis. Spherical silica nanoparticles synthesized from the microreactor have good monodispersity with an average size of 480 nm. The silica nanoparticles produced in the microflow system showed large BET surface area, pore volume, and pore size of 125.08 m2/g, 0.42 cm3/g, and 135.70 Å, respectively. Rhizomucor miehei lipase was successfully adsorbed on the support with lipase activity around 16160 U/g. Increasing the catalyst loading increased the esterification rate from 79% to 97.3% when utilized 2.0 and 2.5 mg/ml of immobilized lipase, respectively. The findings also revealed that, under comparable reaction parameters, immobilized lipase had a higher esterification rate than free lipase. [ABSTRACT FROM AUTHOR]

Cyclodextrin (CD) is an important substance for chemical, pharmaceutical, and food industries. Conventionally, free Escherichia coli (E. coli) cells expressing recombinant cyclodextrin glucanotransferase (CGTase) are used as the biocatalyst for CD production, but the process struggles with low CGTase excretion and CD yield. In this study, E. coli cells were immobilized on hollow‐fiber membranes for β‐CD production, and the process and reaction parameters were optimized via response surface methodology. The reusability of the immobilized cells was also evaluated. The parameter optimization significantly improved β‐CD yield and CGTase excretion, making the process more attractive for industrial applications. The immobilized cells also revealed to be reusable multiple times. [ABSTRACT FROM AUTHOR]

Heme enzymes are the most prominent category of iron-containing metalloenzymes with the capability of catalyzing an astonishingly wide range of reactions like epoxidation, hydroxylation, demethylation, desaturation, reduction, sulfoxidation, and decarboxylation. Various enzymes in this category are P450s, heme peroxidases, catalases, myoglobin, cytochrome C, and others. Besides this, the natural promiscuity and amenability of these enzymes to protein engineering and evolution have also added several non-native reactions such as C–H, N–H, S–H insertions, cyclopropanation, and other industrially important reactions to their capabilities. Surprisingly, all of these reactions and their wide substrate scopes are attributed to changes in the active site scaffold of different heme enzymes as the center of all enzymes is constituted by a porphyrin ring containing iron. Multiple prominent research groups across the world, including 2018, Nobel Laureate Frances Arnold's group, have shown keen interest in engineering and evolving these enzymes for utilizing their industrial potential. Besides engineering the active site, researchers have also explored the possibility of these enzymes catalyzing non-native reactions by replacing the center porphyrin ring with other cofactors or by changing the iron in the porphyrin ring with other metal ions along with engineering the active site and thereby creating novel artificial metalloenzymes. Thus, in this mini-review from our group, for the first time, we are trying to catalog various activities catalyzed by heme enzymes and their engineered variants and their active usage in various industries along with shedding light on their potential for use in various applications in the future. [ABSTRACT FROM AUTHOR]

Enzymatic biodiesel production is a potential eco-friendly alternative to the conventional chemical route which requires extensive study to reduce the costs associated with the application of commercial enzymes. Thus, this study aimed to develop a bioprocess using residues from macauba (Acrocomia aculeata) as raw material for lipase production in solid-state fermentation (SSF) by Yarrowia lipolytica. Then, the product obtained was used as a biocatalyst for the conversion (hydrolysis/esterification) of macauba acidic oil to biodiesel esters. Firstly, different SSF parameters (inoculum concentration, initial moisture content, and carbon and nitrogen levels) were investigated in a factorial design approach, using the cake from macauba fruit. Afterwards, moisture and urea concentration were shown to be statistically significant variables for lipase production. Lipase productnivities were 12.6 ± 0.6 U g−1 h−1 (at 24 h) for macauba fruit cake and 11.6 ± 1 U g−1 h−1 (at 20 h) for macauba pulp and peel cake. The solid enzymatic preparation (biocatalyst) showed optimized values at pH 6–7 at 37 °C, remaining stable (>70% retention) for 90 days at room temperature. Finally, enzymatic hydrolysis of the acidic oil from macauba reached 96% conversion (72 h) to fatty acids, and esterification of fatty acids reached 72% (biodiesel yield of 67%). The bioprocess described is a promising alternative for an integral and self-sufficient valorization of the macauba products. [ABSTRACT FROM AUTHOR]

Agro waste is among potential feedstock for diverse applications due high organic content. In this context, rice straw is a prominent agro waste produced in large volumes. In addition to conventional applications, rice straw can be processed to produce useful products. Present study was designed for eco-friendly utilization of rice straw waste for production of bio-oil and biocatalyst. Pyrolysis of rice straw (in absence and presence of synthesized biocatalyst) was conducted for production of bio-oil and biochar. Bio-MCM-41 as biocatalyst, was synthesised directly from rice straw and also from solid residue obtained after catalytic and non-catalytic pyrolysis of rice straw. Characterization and comparative study of all three catalyst was done through FTIR, XRD SEM and EDX analysis. Catalytic pyrolysis also resulted in enhanced bio-oil production yield of Bio-oil-1 and Bio-oil-2 obtained after non-catalytic pyrolysis and catalytic pyrolysis was 26.78% and 30.34% respectively. The HHV of bio-oil extracted through catalytic pyrolysis was 48.8 ± 0.1 MJ/Kg which was higher when compared to the bio-oil obtained through non-catalytic pyrolysis (37.9 ± 0.2 MJ/Kg) as a result of a lower oxygen content. Reutilization of biochar for biocatalyst synthesis was the novel approach in this study which resulted in complete utilization of rice straw waste, with no residue released into the environment making the overall process environment friendly. Catalyst synthesized directly from rice straw and the catalyst obtained from biochar (recovered after pyrolysis) exhibited similar characteristic features. [ABSTRACT FROM AUTHOR]

Refining petroleum fractions containing heterocyclic sulphur compounds to produce sulphur-free fuels, requires efficient desulphurisation methods. A new biocatalyst has been synthesised by immobilising Pseudomonas aeruginosa cells on polyvinyl alcohol by adsorption for hydro-cracked light gas oil bio-desulphurisation. The surface functional groups and biocatalyst morphology have been investigated by Fourier transform infrared spectroscopy and scanning electron microscopy. The bio-desulphurisation of dibenzothiophene as a heterocyclic sulphur model compound of gas oil was achieved with an aqueous-oil ratio (v/v) of 50 %, where the removed mass was 0.3826 mg per gram of biocatalyst at equilibrium condition, bio-desulphurisation rate of 0.375 h–1 and removal percentage was 95.65 %. The biodegradation of dibenzothiophene and its derivatives in hydro-cracked light gas oil has been determined after a batch process using 0.5 g of the biocatalyst after 5 h of contact time at 37 °C. According to gas chromatography - mass spectrometry, ethyl and trimethyl derivatives of dibenzothiophene have been degraded by higher efficiencies in comparison with other derivatives. Also, thiophenes and mercaptans of the gasoil sample have been degraded simultaneously to some extent. Equilibrium data have been observed to obey the pseudo-first-order kinetic model. The cell immobilisation facilitates the interaction of surface functional groups with sulphur compounds. The synergistic effect of cell immobilisation on the bio-activity of bacterial cells was due to the maintenance of the heterotrophic, bacillus morphology of the cells after immobilisation. This approach provides a simple, economical method with mild operating conditions to produce low-sulphur light gas oil through the biodegradation of heterocyclic sulphur compounds. [ABSTRACT FROM AUTHOR]

Nano-CaO can be used in various fields such as energy, health, and medicine. Clamshell (Geloina sp.) has a large enough CaCO3 content, so it has the potential as a material for making nano-CaO. The synthesis of nano-CaO from shells can be done by the top-down method using high-energy milling. One of the problems with the top-down method is the high energy requirement. The utilization of papaya latex is an effort to reduce energy requirements during the milling process. This study aims to examine the use of papaya latex as a bio-activator in the synthesis of nano-CaO from clamshell (Geloina sp.). Several aspects studied include the yield of nano-CaO obtained and the characteristics of nano-CaO. The results show the optimum conditions for the incubation process with papaya latex were at a temperature of 60 °C, the papaya latex concentration of 5%, and the time of 3 h. The content of Ca, C, and O in nano-CaO is 45.04, 35.07, and 18.36%, respectively. Nano-CaO has a very active group and has antibacterial activity. Therefore, nano-CaO from clamshell (Geloina sp.) can be used in any industrial field. [ABSTRACT FROM AUTHOR]

In this study, a biodegradable and eco-friendly biocatalyst (eggshell/Fe3O4) was synthesized utilizing eggshell impregnated with Fe3O4 nanoparticles. The characterization of prepared catalyst was carried out by Fourier transform infrared radiation (FT-IR), scanning electron microscopy (SEM), X-ray Diffraction (XRD), energy-dispersive X-ray (EDX), thermal gravimetric analysis-differential thermogravimetry (TGA-DTG), vibrating sample magnometer (VSM), and atomic force microscopy (AFM). The eggshell/Fe3O4 biocatalyst was served in multi-component reactions (MCRs) for the synthesis of 2-amino thiophene derivatives from variety aromatic aldehydes, malononitrile, ethyl acetoacetate, and sulfur (S8). To achieve optimal reaction conditions, a thorough examination was conducted on key factors, such as the solvent type, reaction time and temperature, and the ratio of eggshell to Fe3O4. The findings suggest that high yield product can be obtained at microwave temperature (MW) in EtOH solvent within 10 min. Additionally, the eggshell/Fe3O4 biocatalyst exhibited high catalytic activity, which was sustained over the five cycles, without any significant decline in its performance.