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AbstractMitigation of the environment from hazardous pesticides is clamant for all living things. The behavior of the fungicide Fuberidazole was investigated toward biodegradation. Biotransformation experiments were conducted by bacterial strains isolated from soils including, Xanthomonas citri (XC), and Pseudomonas syringae (PS), and fungal strains including, Aspergillus flavus (AF), Aspergillus niger (AN) and Penicillium chrysogenum (PC). Analysis and quantification of Fuberidazole degradation and its metabolites were performed by gas chromatography mass spectrometry and UV-visible spectrophotometry. Pseudomonas syringae and Penicillium chrysogenum displayed great bioremedial potential and degraded 91 and 86% of Fuberidazole after 35 days. Significant metabolites such as Benzimidazole 2-carboxylic acid, Benzimidazole, and 1-(1H-benzimidazole-2-yl)ethanone were produced in the current experiment. The increasing order of half-life for all strains was obtained as, PS (10.3) < PC (10.6) < AN (11) < AF (11.9) = XC (11.9) days. Experimental results demonstrated the capability of bacterial cells to efficiently utilize Fuberidazole as a nutrition source and the significance of favorable environmental conditions for its dissipation. [ABSTRACT FROM AUTHOR]

Formate dehydrogenases (FDHs) catalyze the oxidation of formate to CO2 while reducing NAD(P)+ to NAD(P)H and are classified into two main classes: metal‐dependent (Mo‐ or W‐containing) and metal‐independent FDHs. The latter are oxygen‐tolerant and relevant as a cofactor regeneration system for various bioprocesses and gained more and more attention due to their ability to catalyze the reverse CO2 reduction. This review gives an overview of metal‐independent FDHs, the recent advances made in this field, and their relevance for future applications in biocatalysis. This includes the exploitation of novel FDHs which have altered co‐substrate specificity as well as enzyme engineering approaches to improve process stability and general performance. [ABSTRACT FROM AUTHOR]

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

Coriolopsis gallica (Cga) is a white-rot fungus renowned for its ability to secrete ligninolytic enzymes that are capable of oxidizing phenolic compounds. This study aimed to investigate the biochemical characteristics of a dye-decolorizing peroxidase named CgaDyP1 and test its ability to biotransform antibiotics. CgaDyP1 was cloned and heterologously expressed in Escherichia coli. We fully characterized the biochemical properties of CgaDyP1 and evaluated its dye-decolorizing potential to confirm that it belongs to the DyP class of enzymes. We also tested its fluoroquinolone antibiotic biotransformation potential for possible biotechnological applications. Alignment of the primary amino acid sequence with DyP homolog sequences showed that CgaDyP1 has high similarity with other fungal DyPs. The recombinant CgaDyP1 exhibited activity on substrates such as ABTS and 2,6-dimethoxyphenol (DMP) with optimal performance at a pH of 3, although activity at pH 2.5, pH 4, and pH5 diminished over time. Thermostability tests indicated that the enzyme remains stable at temperatures between 30 °C and 50 °C and retains 70% of its initial activity after 180 min at 50 °C. Tests on the effect of hydrogen peroxide on CgaDyP1 activity found peak activity at 0.25 mM H2O2. CgaDyP1 decolorized five industrial dyes, and kinetics data confirmed that it belongs to the DyP class of enzymes. CgaDyP1 was shown to biotransform some of the 7 recalcitrant fluoroquinolone antibiotics tested here, including levofloxacin, moxifloxacin, and norfloxacin, and thus holds potential for biotechnological applications. [ABSTRACT FROM AUTHOR]

Polycyclic aromatic hydrocarbons (PAHs) are a class of organic compounds frequently detected in the environment with widely varying toxicities. Many PAHs activate the aryl hydrocarbon receptor (AHR), inducing the expression of a battery of genes, including xenobiotic metabolizing enzymes like cytochrome P450s (CYPs); however, not all PAHs act via this mechanism. We screened several parent and substituted PAHs in in vitro AHR activation assays to classify their unique activity. Retene (1-methyl-7-isopropylphenanthrene) displays Ahr2-dependent teratogenicity in zebrafish, but did not activate human AHR or zebrafish Ahr2, suggesting a retene metabolite activates Ahr2 in zebrafish to induce developmental toxicity. To investigate the role of metabolism in retene toxicity, studies were performed to determine the functional role of cyp1a , cyp1b1 , and the microbiome in retene toxicity, identify the zebrafish window of susceptibility, and measure retene uptake, loss, and metabolite formation in vivo. Cyp1a-null fish were generated using CRISPR-Cas9. Cyp1a-null fish showed increased sensitivity to retene toxicity, whereas Cyp1b1-null fish were less susceptible, and microbiome elimination had no significant effect. Zebrafish required exposure to retene between 24 and 48 hours post fertilization (hpf) to exhibit toxicity. After static exposure, retene concentrations in zebrafish embryos increased until 24 hpf, peaked between 24 and 36 hpf, and decreased rapidly thereafter. We detected retene metabolites at 36 and 48 hpf, indicating metabolic onset preceding toxicity. This study highlights the value of combining molecular and systems biology approaches with mechanistic and predictive toxicology to interrogate the role of biotransformation in AHR-dependent toxicity. [ABSTRACT FROM AUTHOR]

Panax ginseng is a precious Chinese medicinal plant with a long growth cycle and high medicinal value. Therefore, it is of great significance to explore effective ways to increase its yield and main active substance content to reduce the cost of ginseng, which is widely used in food and clinical applications. Here, we review the key roles of microorganisms in the biological control of ginseng diseases, enhancement of ginseng yield, biotransformation of ginsenosides, and augmentation of ginsenoside bioactivity. The application of microorganisms in P. ginseng faces multiple challenges, including the need for further exploration of efficient microbial strain resources used in the cultivation of ginseng and biotransformation of ginsenosides, lack of microbial application in large-scale field cultivation of ginseng, and unclear mechanism of microbial transformation of ginsenosides. This review provides a deeper understanding of the applications of microorganisms in P. ginseng. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl sulfonamides (FASAs) and other FASA‐based per‐ and polyfluoroalkyl substances (PFASs) can transform into recalcitrant perfluoroalkyl sulfonates in vivo. We conducted high‐resolution mass spectrometry suspect screening of urine and tissues (kidney and liver) from mice dosed with an electrochemically fluorinated aqueous film‐forming foam (AFFF) to better understand the biological fate of AFFF‐associated precursors. The B6C3F1 mice were dosed at five levels (0, 0.05, 0.5, 1, and 5 mg kg−1 day−1) based on perfluorooctane sulfonate and perfluorooctanoate content of the AFFF mixture. Dosing continued for 10 days followed by a 6‐day depuration. Total oxidizable precursor assay of the AFFF suggested significant contributions from precursors with three to six perfluorinated carbons. We identified C4 to C6 FASAs and N‐glucuronidated FASAs (FASA‐N‐glus) excreted in urine collected throughout dosing and depuration. Based on normalized relative abundance, FASA‐N‐glus accounted for up to 33% of the total excreted FASAs in mouse urine, highlighting the importance of phase II metabolic conjugation as a route of excretion. High‐resolution mass spectrometry screening of liver and kidney tissue revealed accumulation of longer‐chain (C7 and C8) FASAs not detected in urine. Chain‐length–dependent conjugation of FASAs was also observed by incubating FASAs with mouse liver S9 fractions. Shorter‐chain (C4) FASAs conjugated to a much greater extent over a 120‐min incubation than longer‐chain (C8) FASAs. Overall, this study highlights the significance of N‐glucuronidation as an excretion mechanism for short‐chain FASAs and suggests that monitoring urine for FASA‐N‐glus could contribute to a better understanding of PFAS exposure, as FASAs and their conjugates are often overlooked by traditional biomonitoring studies. Environ Toxicol Chem 2024;43:2274–2284. © 2024 The Author(s). Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

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

Background: Rapid utilization of natural resources and other anthropogenic activities intruded heavy metals into the food chain and raised alarming concern for all life forms. The available methods proved insufficient in handling waste and pollutants due to the high cost and generation of toxic residues. Bioremediation strategies have offered sustainable solutions for toxic pollutants. In the current study, cadmium and lead (Cd and Pb respectively) tolerant strains have been isolated from industrial effluent and characterized for tolerance towards target pollutants. The strain was identified by 16s rRNA gene and further used for metal removal from the industrial effluents. Results: Bacterial isolates were obtained from industrial discharge and evaluated for their tolerance towards Cd and Pb. AS-1 bacterial isolate exhibited maximum tolerance towards both the metals and hence was selected for further study. The isolate was identified as Staphylococcus epidermidis. ICP-MS and energy dispersive X-ray (EDX) analysis of biomass revealed that a significant proportion of cadmium (90.89%) and lead (94.87%) available in effluent were sequestered within bacterial biomass. Characteristic peaks at 2Ɵ (31.8637 and 45.6247 for cadmium) and (21.0397, 27.0127, 46.0537, 54.2707 and 75.6547 for lead) confirmed the crystalline nature of the sequestered metals. The selected strain was characterized on biochemical and molecular basis and was found to be Staphylococcus epidermidis. Based on 16 S rDNA sequence analysis, a phylogenetic dendrogram was created for the maximum likelihood of the bacterial strain. The sequence was deposited in the NCBI repository (accession number PP587422). Conclusion: The work has shown the possible way out of heavy metal pollution sustainably. To the best of the author's knowledge, this is the first report on the sequestration and reduction of cadmium and lead by a nonpathogenic strain of Staphylococcus epidermidis AS-1 that may be useful for alleviating heavy metal contamination. [ABSTRACT FROM AUTHOR]

The widely used non-steroidal anti-inflammatory drug, diclofenac, detected in increasing concentrations in freshwater ecosystems, is among the most pressing environmental problems today. In this study, the bacterial isolate Stenotrophomonas humi strain DIC_5 was capable of degrading diclofenac. It eliminated 75.1% of diclofenac at an initial concentration of 1.5 mg/L after 8 days in the presence of glucose (3.0 g/L). During the process, nitro-diclofenac was identified as a resulting metabolite, whose concentration increased significantly in the bacterial medium from the 7th day of the experiment, while the concentration of diclofenac decreased correspondingly. The ecotoxicological tests on Aliivibrio fischeri and zebrafish embryos showed that the bacterial metabolites without diclofenac have a higher toxicity (up to 35.5% bacterial bioluminescence inhibition and 36.7% embryo mortality) than the diclofenac degradation residues (28% and 26.7%, respectively). Based on these results, neither diclofenac nor its degradation products exhibit toxic effects on the test organisms. Conversely, the toxic effect caused by the bacteria was reduced in the presence of diclofenac. Our work highlights the importance of using biotic controls in biotransformation trials, especially when the foreign material is applied in intermediate or environmentally relevant concentration ranges. Key points: • Biotransformation of diclofenac by bacteria isolated from a bacterial biofilm. • Biotransformation of diclofenac led to the formation of nitro-diclofenac. • Microorganisms are alternatives for reducing the concentration of diclofenac in water. [ABSTRACT FROM AUTHOR]

The reduction of oximes was recently identified as a promiscuous activity of Old Yellow Enzymes (OYEs). This reaction involves a two‐step reduction of α‐oxime‐ß‐ketoesters to the corresponding amines, which spontaneously dimerise to yield pyrazine derivatives. This biotransformation is currently limited to substrates with small substituents like methyl/ethyl on the keto moiety. We used a structure‐based approach to engineer 12‐oxophytodienoate reductase 3 (OPR3) from Solanum lycopersicum as a prototypical OYE to accept oximes with bulkier substituents. To this end, three single and two double variants were prepared and tested on six oxime substrates. The engineered variants indeed showed activity on some of the bulkier substrates, which had not been converted at all by the wild‐type enzyme, including the diester compound diethyl‐2‐(hydroximino) malonate. While we were unable to identify variants capable of converting substrates with branched and aromatic substituents, the results demonstrate the validity of our engineering approach, suggesting potential pathways for expanding the substrate scope of OYEs. [ABSTRACT FROM AUTHOR]

Background: Poekilocerus pictus (Fabricius 1771), a painted grasshopper, sequesters cardenolides from its food plant, the Apple of Sodom or Aak, Calotropis procera (Aiton) W.T. Aiton (Family-Asclepiadaceae). In our present investigation, we were able to isolate Pseudomonas aeruginosa KRK6 from the intestine of Poekilocerus pictus responsible for the biotransformation of cardenolides. Methods: Pseudomonas aeruginosa KRK6 was grown in methanolic extracts of Calotropis procera and the modified cardenolides were detected by Liquid Chromatography-Mass Spectrometry (LCMS) and also used to induce apoptosis in cancer cells (MCF-7 cells and T-47 D). Result: The modified cardenolides CPMEP6 was found to induce apoptosis in human breast adenocarcinoma cells (MCF cells-IC50= 6.31±0.4 µg/mL, T-47D cells-IC50= 10.1±1.02 µg/mL). Phosphatidylserine exposure and DNA fragmentation suggested apoptosis in treated cancer cells. CPMEP6 induced apoptosis in cancer cells via the mitochondrial pathway by down-regulating BCL-2 protein expression and up-regulating BAX protein expression. [ABSTRACT FROM AUTHOR]

Since ancient times, humans have turned to medicinal plants for treating various ailments and curing specific diseases, as these natural plants serve as the primary source of a range of phytochemicals, including triterpenes. Maslinic acid (MA), also known as (2α,3β)-2,3-dihydroxyolean-12-en-28-oic acid, is a pentacyclic triterpene acid present in numerous plants including olive, known for its high safety profile in humans. Recent experimental data increasingly suggests that MA exhibits diverse biological properties and therapeutic effects on various organ diseases, highlighting its significant potential for clinical applications due to its diverse potential pharmacological activities that promote health and resist various diseases, such as hypoglycemic, neuroprotective, anti-tumor, anti-inflammatory, antioxidant and multiple other biological activities. However, the undesirable pharmacokinetic properties of MA, such as high lipophilicity, pose a limitation to its application and development, impacting its bioavailability. Consequently, extensive research spanning decades has focused on structurally modifying MA to overcome these limitations and enhance its pharmacokinetic and therapeutic characteristics, leading to the identification of several potential lead compounds. In this review, we focus on the progress of research in recent years on MA with interest to its chemical and enzymatic modifications as well as the relationships between the modified structures or derivatives and their biological activities. [ABSTRACT FROM AUTHOR]

Aficamten, a cardiac myosin inhibitor, is being developed for the treatment of patients with symptomatic hypertrophic cardiomyopathy (HCM). The purpose of this study was to determine the absorption, metabolism, and excretion of aficamten. Eight healthy male participants received a single oral dose of 20 mg aficamten (containing approximately 100 μCi of radiocarbon). Blood, urine, and feces samples were collected up to a maximum of Day 26. The pharmacokinetics of aficamten were characterized by moderate absorption, with a median tmax of 2.0 h postdose. The median t1/2 of aficamten was 99.6 h with similar t1/2 observed for metabolites and total radioactivity in plasma and whole blood. The overall total recovery of administered total radioactivity was 89.7% with 57.7% of the dose recovered in feces and 32.0% in urine. The main circulating metabolites in plasma included monohydroxylated metabolites M1a (CK‐3834282) and M1b (CK‐3834283) accounting for 10.5% and 36.4% of the total radioactivity AUC both with a median tmax of 5 h. The other major plasma metabolite was M5 (an oxygen‐linked glucuronide conjugate of M1a), which accounted for 10.3% of the total plasma radioactivity exposure, with a tmax of 24 h. In urine, M5 was the most abundant metabolite with 8.02% total radioactive dose (TRD), followed by M1a and M1b with 6.16% and 2.85% TRD, respectively; however, there were no metabolites in urine observed at >10% of dose. The major metabolite in feces was M18 representing 44.1% of the radioactive dose. These findings indicated that aficamten was eliminated by metabolism, and to a minor extent, by fecal excretion of unchanged aficamten with renal excretion playing a minor role. Feces were the principal route of excretion of the radioactive dose. [ABSTRACT FROM AUTHOR]

Cytochrome P450 monooxygenases are recognized as versatile biocatalysts due to their broad reaction capabilities. One important reaction is the hydroxylation of non-activated C–H bonds. The subfamily CYP153A is known for terminal hydroxylation reactions, giving access to functionalized aliphatics. Whilst fatty derivatives may be converted by numerous enzyme classes, midchain aliphatics are seldomly accepted, a prime property of CYP153As. We report here on a new CYP153A member from the genome of the mesophilic actinobacterium Gordonia rubripertincta CWB2 as an efficient biocatalyst. The gene was overexpressed in Escherichia coli and fused with a surrogate electron transport system from Acinetobacter sp. OC4. This chimeric self-sufficient whole-cell system could perform hydroxylation and epoxidation reactions: conversions of C6–C14 alkanes, alkenes, alcohols and of cyclic compounds were observed, yielding production rates of, e.g., 2.69 mM h−1 for 1-hexanol and 4.97 mM h−1 for 1,2-epoxyhexane. Optimizing the linker compositions between the protein units led to significantly altered activity. Balancing linker length and flexibility with glycine-rich and helix-forming linker units increased 1-hexanol production activity to 350 % compared to the initial linker setup with entirely helical linkers. The study shows that strategic coupling of efficient electron supply and a selective enzyme enables previously challenging monooxygenation reactions of midchain aliphatics. [ABSTRACT FROM AUTHOR]

The quest for novel therapeutic agents has rekindled interest in natural products, particularly those derived from biotransformation processes. Dihydrochalcones, a class of plant secondary metabolites, exhibit a range of pharmacological properties. Chalcone and dihydrochalcone compounds with the characteristic 4'-hydroxy substitution are present in 'dragon's blood' resin, known for its traditional medicinal uses and complex composition, making the isolation of these compounds challenging. This study investigates the efficient production of 4′-hydroxydihydrochalcones using non-conventional yeast strains. We evaluated the biotransformation efficiency of various 4′-hydroxychalcone substrates utilizing yeast strains such as Yarrowia lipolytica KCh 71, Saccharomyces cerevisiae KCh 464, Rhodotorula rubra KCh 4 and KCh 82, and Rhodotorula glutinis KCh 242. Our findings revealed that Yarrowia lipolytica KCh 71, Rhodotorula rubra KCh 4 and KCh 82, and Rhodotorula glutinis KCh 242 exhibited the highest conversion efficiencies, exceeding 98% within one hour for most substrates. The position of methoxy substituents in the chalcone ring significantly influenced hydrogenation efficiency. Moreover, we observed isomerization of trans-4′-hydroxy-2-methoxychalcone to its cis isomer, catalyzed by light exposure. This study underscores the potential of using yeast strains for the sustainable and efficient production of dihydrochalcones, providing a foundation for developing new therapeutic agents and nutraceuticals. [ABSTRACT FROM AUTHOR]

Xanthohumol (1) is a major prenylated flavonoid in hops (Humulus lupulus L.) which exhibits a broad spectrum of health-promoting and therapeutic activities, including anti-inflammatory, antioxidant, antimicrobial, and anticancer effects. However, due to its lipophilic nature, it is poorly soluble in water and barely absorbed from the gastrointestinal tract, which greatly limits its therapeutic potential. One method of increasing the solubility of active compounds is their conjugation to polar molecules, such as sugars. Sugar moiety introduced into the flavonoid molecule significantly increases polarity, which results in better water solubility and often leads to greater bioavailability. Entomopathogenic fungi are well known for their ability to catalyze O-glycosylation reactions. Therefore, we investigated the ability of selected entomopathogenic filamentous fungi to biotransform xanthohumol (1). As a result of the experiments, one aglycone (2) and five glycosides (3–7) were obtained. The obtained (2″E)-4″-hydroxyxanthohumol 4′-O-β-D-(4‴-O-methyl)-glucopyranoside (5) has never been described in the literature so far. Interestingly, in addition to the expected glycosylation reactions, the tested fungi also catalyzed chalcone–flavanone cyclization reactions, which demonstrates chalcone isomerase-like activity, an enzyme typically found in plants. All these findings undoubtedly indicate that entomopathogenic filamentous fungi are still an underexploited pool of novel enzymes. [ABSTRACT FROM AUTHOR]

Propolis is a natural resinous compound produced by bees, mixed with their saliva and wax, and has a range of biological benefits, including antioxidant and anti-inflammatory effects. This article reviews the in vivo transformation of propolis flavonoids and their potential influence on drug efficacy. Despite propolis is widely used, there is little research on how the active ingredients of propolis change in the body and how they interact with drugs. Future research will focus on these interactions and the metabolic fate of propolis in vivo. [ABSTRACT FROM AUTHOR]

Green tea has garnered widespread interest in the past decades due to its content of health-beneficial polyphenols and catechins, besides reportedly exhibiting activities for the prevention, and possibly treatment, of many modern-life-associated afflictions. Hence, the functional food potential of health-beneficial beverages such as green tea is widely and commercially promoted. Biotransformation of green tea extract using enzymes such as tannase ostensibly enhances its beneficial well-being properties and disease-preventing functionalities. The tannase-treated green tea catechins may exhibit enhanced, amongst others, antioxidant, anti-tumour, anti-wrinkle, anti-inflammatory, anti-obesity and anti-sarcopenia properties compared to native green tea extract. Nonetheless, the health benefits and therapeutic and toxicological effects associated with these compounds, before and after tannase treatment, present a scientific gap for detailed studies. Accordingly, the review surveys the literature from the late twentieth century until the year 2023 related to the aforementioned important aspects. [ABSTRACT FROM AUTHOR]

Drug biotransformation studies emerges as an alternative to pharmacological investigations of metabolites, development of new drug candidates with reduced investment and most efficient production. The present study aims to evaluate the capacity of biotransformation of rifampicin by the filamentous fungus Aspergillus niger ATCC 9029. After incubation for 312 h, the drug was metabolized to two molecules: an isomer (m/z 455) and the rifampicin quinone (m/z 821). The monitoring of metabolite formation was performed by high‐performance liquid chromatography, followed by their identification through ultra‐high‐performance liquid chromatography coupled to tandem mass spectrometer. In vitro antimicrobial activity of the proposed metabolites was evaluated against Staphylococus aureus microorganism, resulting in the loss of inhibitory activity when compared with the standards, with minimum inhibitory concentration of 7.5 μg/ml. The significant biotransformation power of the ATCC 9029 strain of A. niger was confirmed in this study, making this strain a candidate for pilot studies in fermentation tanks for the enzymatic metabolization of the antimicrobial rifampicin. The unprecedented result allows us to conclude that the prospect of new biotransforming strains in species of anemophilic fungi is a promising choice. [ABSTRACT FROM AUTHOR]

The present study revealed the consequences of the interaction of a widely used bioinsecticide and endophyte Metarhizium anisopliae with the hazardous mycotoxin zearalenone (ZEN) as a pure substance and with ZEN as a native component of a crude Fusarium extract. In the environment, microorganisms encounter a mixture of metabolites secreted by other organisms living in the same area, not single substances. The obtained results suggest that M. anisopliae, exposed to a variety of active substances produced by Fusarium graminearum, is able to eliminate ZEN. Within 14 days, M. anisopliae biotransformed 90.8% and 85.8% of ZEN as a pure substance and ZEN as a native component of the F. graminearum extract from Rice Medium (E-Fg-RM), respectively, through reduction predominantly to α-epimers of zearalenols and zearalanols, considered more estrogenic than ZEN, which can raise concerns. Compared to pure ZEN, E-Fg-RM significantly affected the production of Metarhizium secondary metabolites by increasing the destruxins amount by approximately 20–25% and reducing the swainsonine content by 96.2%. All these findings provide a possible picture of the interaction of M. anisopliae with ZEN in the wild, mainly as a result of the use of crude extract from Fusarium, which contained a mixture of different metabolites. [ABSTRACT FROM AUTHOR]

AbstractThe structural modification of natural products using biotransformation is an effective way to produce organic compounds in a regioselective and/or stereoselective manner. O-methylation is a major modification in nature. The predicted data mining approach (PDMA) can efficiently screen out biotransformable precursor candidates to produce new (functional) compounds from thousands of derivatives. Herein, an O-methyltransferase (SpOMT2884) from Streptomyces peucetius (ATCC 27952 strain) was selected to biotransform eight precursors, screened from 4364 commercially available natural compounds via PDMA. Seven of the eight precursors (calceolarioside B, isomangiferin, mangiferin, methyl chlorogenate, plantagoside, protosappanin B, and wedelolactone) could be biotransformed from SpOMT2884. Fourteen biotransformed compounds were confirmed to be methyl products with a high-resolution mass analysis. Three methyl products from two precursors (plantagoside and protosappanin B) were selected for further production and identified using nucleic magnetic resonance spectral methods. One methyl product of protosappanin B was identified as 10-O-methyl protosappanin B (1), which gained potent anti-inflammatory activity (IC50 = 76.1 ± 4.7 μM) compared with its precursor, protosappanin B (IC50 = 157.7 ± 5.0 μM). In a case study, two methyl products of plantagoside were indeed identified as novel 4′-O-methyl plantagoside (3) and 5′-O-methyl plantagoside (4). This study demonstrates that PDMA is a good in silico approach for screening biotransformable precursor candidates for the in vitro production of new or bioactive compounds from numerous natural products. [ABSTRACT FROM AUTHOR]

Paraoxonase 1 (PON1) is an antioxidant enzyme that prevents lipid oxidation by hydrolysing lipid peroxides in the oxidised low‐density lipoprotein (LDL) structure, bound to high‐density lipoprotein (HDL) in serum, and exhibits esterase and lactonase activity. In this work, the hPON1 enzyme was purified from human serum using a hydrophobic gel with Sepharose 4B‐L‐tyrosine‐naphthylamine, and the affinity of some steroid derivatives previously isolated from fungal steroid biotransformations was examined on the pure hPON1 enzyme. The results indicate that all these derivaties activate the hPON1 enzyme to a different extent. Additionally, the binding potential of the most active five steroid derivatives to the PON1 enzyme to form a stable complex was explored through molecular docking and molecular dynamics (MD) simulation. The compounds with the highest potency in the enzymatic assay, S‐8 and S‐20, had the highest binding potential to the enzyme. The stability of the complexes formed by the two compounds was assessed and compared to the stability of the unbound enzyme structure. The enzyme‐compound complexes generally had similar stability to the unbound enzyme structure. Together with this, the MD simulation revealed that compound S‐8 would remain inside the enzyme's binding site during the simulation period, unlike compound S‐20. This situation varies according to the respective derivatives' functional groups and hydrophobic characteristics. [ABSTRACT FROM AUTHOR]

Methanotrophs are bacteria that consume methane (CH4) as their sole carbon and energy source. These microorganisms play a crucial role in the carbon cycle by metabolizing CH4 (the greenhouse gas), into cellular biomass and carbon dioxide (CO2). Polyhydroxyalkanoates (PHAs) are biopolymers produced by various microorganisms, including methanotrophs. PHA production using methanotrophs is a promising strategy to address growing concerns regarding plastic pollution and the need for sustainable, biodegradable materials. Various factors, including nutrient availability, environmental conditions, and metabolic engineering strategies, influence methanotrophic production. Nutrient limitations, particularly those of nitrogen or phosphorus, enhance PHA production by methanotrophs. Metabolic engineering approaches, such as the overexpression of key enzymes involved in PHA biosynthesis or the disruption of competing pathways, can also enhance PHA yields by methanotrophs. Overall, PHA production by methanotrophs represents a sustainable and versatile approach for developing biomedical materials with numerous potential applications. Additionally, alternative feedstocks, such as industrial waste streams or byproducts can be explored to improve the economic feasibility of PHA production. This review briefly describes the potential of methanotrophs to produce PHAs, with recent updates and perspectives. [ABSTRACT FROM AUTHOR]

Morocco's management of agri-food waste presents serious environmental problems that threaten natural environment and human health. It has become crucial to use more effective technologies, like composting or anaerobic digestion, for recycling food waste in order to address this problem. Such technologies must to not only provide solutions but also provide beneficial outcomes. Therefore, conducting comparative studies to identify the most effective technologies is crucial. The present study aims to examine the potential of converting this waste into a high-quality biofertilizer by comparing between the aerobic and anaerobic bioconversion with the use of a fungal inoculum in order to enhance the quality and time of the biological process. Additionally, the study examines the effect of using a single type of waste or a variety of wastes on the quality of the biofertilizer produced. A fungus known for its capacity to accelerate biotransformation, Aspergillus niger, was added to a mixture of fish, vegetable, and poultry wastes. In a 20-day process, the impact of waste formulation on nutritional and hygienic potential was assessed based on biofertilization standards. According to the results, a combination of all three waste types with a tiny excess of poultry waste was the best mixture for biofertilization. Regardless of the bioconversion mechanism employed, this mixture was proven to be effective and secure. Anaerobic digestion product had a higher potential for biofertilization than aerobic biotransformation product, according to fertilization tests on tomato crops. Therefore, choosing the most appropriate method of bioconversion is essential to produce a high-quality biofertilizer that can enhance plant growth. [ABSTRACT FROM AUTHOR]

Bioaromas can be produced by lipases either through their hydrolytic or (trans)esterifying activities. Therefore, this work reports the development of a lipase-catalyzed biotransformed licuri oil, forming volatile ethyl esters with odor notes resembling tropical fruits. Ethyl octanoate formation was promoted when 7.0 % (m/v) Lipozyme 435® was used to convert a grain alcohol:licuri oil mixture (51:49, v/v) at 58ºC and 70 rpm for 6 hours. The biotransformed oil has shown antimicrobial activity against Staphylococcus hominis , S. epidermidis, and Corynebacterium xerosis , bacteria associated with bad skin odor. Finally, this biotransformed oil was used without further treatments (e.g., recovery or purification procedures) to prepare two cosmetic formulations (in a dosage of 1.5 %), aiming for both fragrant and deodorant activity. • Odor-active ethyl esters were formed in lipase-biotransformed licuri oil. • 8.22 g/L ethyl octanoate was formed with 7 % lipase, 51:49 alcohol:oil ratio at 58°C. • Antibacterial activity of biotransformed oil could prevent bad skin odor. • Cosmetic formulations were prepared with 1.5 % biotransformed licuri oil. • No purification procedures were needed to use a natural fragrant mixture. [ABSTRACT FROM AUTHOR]

Zearalenone and radicicol are resorcylic acid lactones produced by numerous plant pathogenic fungi. Zearalenone is a non-steroidal estrogen mimic that can cause serious reproductive issues in livestock that consume contaminated feed. Radicicol is a potent inhibitor of the molecular chaperone Hsp90, which, in plants, has an important role in coordinating the host's immune response during infection. Here, we describe the identification and characterization of a soil-borne strain of the Gram-positive bacterium Aeromicrobium sp. capable of hydrolyzing the macrolide ring of resorcylic acid lactones, including zearalenone and radicicol. Proteomic analysis of biochemically enriched fractions from the isolated and cultured bacterium identified an α/β-hydrolase responsible for this activity. A recombinantly expressed and purified form of the hydrolase (termed RALH) was active against both zearalenone and radicicol. Interpretation of high-resolution mass spectrometry and NMR data confirmed the structures of the enzymatic products as the previously reported non-toxic metabolite hydrolyzed zearalenone and hydrolyzed radicicol. Hydrolyzed radicicol was demonstrated to no longer inhibit the ATPase activity of the Saccharomyces cerevisiae Hsp90 homolog in vitro. Enzymatic degradation of resorcylic acid lactones will enable insight into their biological functions. [ABSTRACT FROM AUTHOR]

SUMMARY: Improvement of photosynthesis requires a thorough understanding of electron partitioning under both natural and strong electron sink conditions. We applied a wide array of state‐of‐the‐art biophysical and biochemical techniques to thoroughly investigate the fate of photosynthetic electrons in the engineered cyanobacterium Synechocystis sp. PCC 6803, a blueprint for photosynthetic biotechnology, expressing the heterologous gene for ene‐reductase, YqjM. This recombinant enzyme catalyses the reduction of an exogenously added substrate into the desired product by utilising photosynthetically produced NAD(P)H, enabling whole‐cell biotransformation. Through coupling the biotransformation reaction with biophysical measurements, we demonstrated that the strong artificial electron sink, outcompetes the natural electron valves, the flavodiiron protein‐driven Mehler‐like reaction and cyclic electron transport. These results show that ferredoxin‐NAD(P)H‐oxidoreductase is the preferred route for delivering photosynthetic electrons from reduced ferredoxin and the cellular NADPH/NADP+ ratio as a key factor in orchestrating photosynthetic electron flux. These insights are crucial for understanding molecular mechanisms of photosynthetic electron transport and harnessing photosynthesis for sustainable bioproduction by engineering the cellular source/sink balance. Furthermore, we conclude that identifying the bioenergetic bottleneck of a heterologous electron sink is a crucial prerequisite for targeted engineering of photosynthetic biotransformation platforms. Significance Statement: We coupled the photosynthetic and biocatalytic (whole‐cell biotransformation) performance of model cyanobacteria. We employed a heterologous NAD(P)H utilising enzyme, as a strong artificial electron sink, allowing us to gain a comprehensive understanding of photosynthetic electron partitioning. We demonstrated that the strong electron sink outcompetes natural electron sinks and cyclic electron transport. [ABSTRACT FROM AUTHOR]

Gingerols are phenolic biomedical compounds found in ginger (Zingiber officinale) whose low aqueous solubility limits their medical application. To improve their solubility and produce novel glucosides, an α -glucosidase (glycoside hydrolase) from Agrobacterium radiobacter DSM 30147 (Ar G) was subcloned, expressed, purified, and then confirmed to have additional α -glycosyltransferase activity. After optimization, the Ar G could glycosylate gingerols into three mono-glucosides based on the length of their acyl side chains. Compound 1 yielded 63.0 %, compound 2 yielded 26.9 %, and compound 3 yielded 4.37 %. The production yield of the gingerol glucosides optimally increased in 50 mM phosphate buffer (pH 6) with 50 % (w/v) maltose and 1000 mM Li+ at 40 °C for an 24-h incubation. The structures of purified compound 1 and compound 2 were determined as 6-gingerol-5- O - α -glucoside (1) and novel 8-gingerol-5- O - α -glucoside (2), respectively, using nucleic magnetic resonance and mass spectral analyses. The aqueous solubility of the gingerol glucosides was greatly improved. Further assays showed that, unusually, 6-gingerol-5- O - α -glucoside had 10-fold higher anti-inflammatory activity (IC 50 value of 15.3 ± 0.5 μM) than 6-gingerol, while the novel 8-gingerol-5- O - α -glucoside retained 42.7 % activity (IC 50 value of 106 ± 4 μM) compared with 8-gingerol. The new α -glucosidase (Ar G) was confirmed to have acidic α -glycosyltransferase activity and could be applied in the production of α -glycosyl derivatives. The 6-gingerol-5- O - α -glucoside can be applied as a clinical drug for anti-inflammatory activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Structurally unique isopentenyl flavonoids are extremely low in natural plant species, and their cumbersome chemical pathways, scarcity of donors, and poor stability have severely hindered their application scenarios. Xanthohumol (XN), an isopentenyl chalcone, is a unique and abundant herbal efficacy substance in hops (Humulus upulus L.), which is an herb with a variety of clinical benefits. However, 90% of XN is left behind in the production of hop residue, resulting in a waste of natural resources. The poor water solubility and low bioavailability of XN also limit its wide application. Combined biotransformation strategies can greatly enhance the added value of resource materials and become one of the important means for the sustainable utilization of traditional Chinese medicine resources. In this study, an extreme microbial screening strategy for efficient bioconversion of phrenylflavonids is established to achieve Bacillus zanthoxyli GQ8 obtained from brewer's dregs and a non-aqueous biosynthesis system of xanthohumol glycosides (XNG, substrate concentration of 0.5 g/L, conversion rate of 73.2%) is constructed by GQ8. With HT22 cell model of H 2 O 2 -induced oxidative damage and BV2 cell model of LPS-induced neuroinflammation, XNG showed little cytotoxicity and exhibited better anti-inflammatory and antioxidant effects compared with the original compound. Our experimental results firstly provide a high-efficiency biotransformation strategy for glycosylation of XN with bacteria and provide a support that prenylflavonoid glycoside derivatives have remarkable biological activity and show better development potential. [Display omitted] • An extreme microbial screening strategy for efficient bioconversion of xanthohumol is established. • Xanthohumol is converted to xanthohumol glycoside by bacterial for the first time. • The product of Xanthohumol shows significant neuroprotective potential. • Bacillus zanthoxyli GQ8 has substrate hybridity so that realizes the transformation of various flavonoids. [ABSTRACT FROM AUTHOR]

Chalcone is a simple naturally occurring α,β-unsaturated ketone with biological importance, which can also be easily synthesized in laboratories by reaction between two aromatic scaffolds. In plants, chalcones occur as polyphenolic compounds of different frameworks which are bioactive molecules that have been in traditional medicinal practice for many years. Chalcone-based lead molecules have been developed, possessing varied potentials such as antimicrobial, antiviral, anti-inflammatory, anticancer, anti-oxidant, antidiabetic, antihyperurecemic, and anti-ulcer effects. Chalcones contribute considerable fragments to give important heterocyclic molecules with therapeutic utilities targeting various diseases. These characteristic features have made chalcone a topic of interest among researchers and have attracted investigations into this widely applicable structure. This review highlights the extensive exploration carried out on the synthesis, biotransformations, chemical reactions, hybridization, and pharmacological potentials of chalcones, and aims to provide an extensive, thorough, and critical review of their importance, with emphasis on their properties, chemistry, and biomedical applications to boost future investigations into this potential scaffold in medicinal chemistry. [ABSTRACT FROM AUTHOR]

Toxicokinetic (TK) assays and in vitro–in vivo extrapolation (IVIVE) models are New Approach Methods (NAMs) used to translate in vitro points of departure to exposure estimates required to reach equivalent blood concentrations. Per- and polyfluoroalkyl substances (PFAS) are a large chemical class with wide-ranging industrial applications for which only limited toxicity data are available for human health evaluation. To address the lack of TK data, a pooled primary human hepatocyte suspension model was used with targeted liquid chromatography–mass spectrometry to investigate substrate depletion for 54 PFAS. A median value of 4.52 μL/(min x million cells) was observed across those that showed significant clearance, with 35 displaying no substrate depletion. Bayesian modeling propagated uncertainty around clearance values for use in IVIVE models. Structural evaluations showed the fluorotelomer carboxylic acids were the only PFAS carboxylates showing appreciable clearance, and per- and polyfluorosulfonamides were more readily metabolized than other PFAS sulfonates. Biotransformation product prediction, using the chemical transformation simulator, suggested hydrolysis of PFAS sulfonamides to more stable sulfonic acids, which is an important consideration for exposure modeling. This effort greatly expands the PFAS in vitro toxicokinetic dataset, enabling refined TK modeling, in silico tool development, and NAM-based human health evaluations across this important set of emerging contaminants. [ABSTRACT FROM AUTHOR]

Ginsenoside F2 is a protopanaxadiol saponin compound with various biological activities, including antioxidant, anti-inflammatory, and anticancer properties. Ginsenoside F2 can be found in ginseng, but in low quantities. Therefore, ginsenoside F2 production predominantly relies on the biotransformation of various ginsenosides, such as ginsenosides Rb1 and Rd. In this study, we reported the production of ginsenoside F2 by gypenoside biotransformation with Aspergillus niger JGL8, isolated from Gynostemma pentaphyllum. Ginsenoside F2 could be produced by two different biotransformation pathways, namely Gyp-V–Rd–F2 and Gyp-XVII–F2. The product exhibited antioxidant activity against free radicals (DPPH) with IC50 value of 29.54 µg/mL. Optimal biotransformation conditions were a pH of 5.0, temperature of 40 °C, and 2 mg/mL of substrate. Enzyme kinetic parameters revealed that the hydrolysis rate of Gyp-V, Rd, and Gyp-XVII was 0.625, 0.588, and 0.417 mM/h, respectively. In conclusion, we demonstrated that gypenoside is a substitutable substrate for ginsenoside F2 biotransformation. [ABSTRACT FROM AUTHOR]

Biotransformation of 6:2 fluorotelomer sulfonate (6:2 FTS) by two species of white-rot fungi, Pleurotus ostreatus (P. ostreatus) and Trametopsis cervina (T. cervina), was investigated in a sulfur-rich medium designed to stimulate production of lignin-degrading enzymes. Degradation of 6:2 FTS was observed by T. cervina over the study period of 30 d, but not by P. ostreatus. Biotransformation rates were comparable to those found in other studies investigating mixed culture degradation in non-sulfur limiting media, with approximately 50 mol% of applied 6:2 FTS removed after 30 d. Stable transformation products were short-chain perfluorocarboxylic acids (PFCAs), including PFHxA (2.27 mol%), PFPeA (0.24 mol%), and PFBA (0.28 mol%). The main intermediate products include 5:2 sFTOH (16.3 mol%) and 5:3 FTCA (2.99 mol%), while 6:2 FTCA, 6:2 FTuCA, and 5:2 ketone were also identified at low levels. Approximately 60 mol% of detected products were assigned to the major pathway to 5:2 ketone, and 40 mol% were assigned to the minor pathway to 5:3 FTCA. The overall molar balance was found to decrease to 75 mol% by Day 30, however, was closed to near 95 mol% with a theoretical estimation for the volatile intermediates in the headspace, 5:2 ketone and 5:2 sFTOH. The different capabilities of the two white-rot fungal species for 6:2 FTS biotransformation in sulfur-rich media suggest that the enzyme processes of T. cervina to de-sulfonate 6:2 FTS may be unrelated to sulfur metabolism. [ABSTRACT FROM AUTHOR]

The discovery of natural products has been pivotal in drug development, providing a vast reservoir of bioactive compounds from various biological sources. This narrative review addresses a critical research gap: the largely underexplored role of gut microbiota in the mediation and biotransformation of medicinal herb-derived natural products for therapeutic use. By examining the interplay between gut microbiota and natural products, this review highlights the potential of microbiota-mediated biotransformation to unveil novel therapeutic agents. It delves into the mechanisms by which gut microbes modify and enhance the efficacy of natural products, with a focus on herbal medicines from Ayurveda and traditional Chinese medicine, known for their applications in treating metabolic and inflammatory diseases. The review also discusses recent advances in microbiota-derived natural product research, including innovative methodologies such as culturomics, metagenomics, and metabolomics. By exploring the intricate interactions between gut microorganisms and their substrates, this review uncovers new strategies for leveraging gut microbiota-mediated processes in the development of groundbreaking therapeutics. [ABSTRACT FROM AUTHOR]

Ciguatoxins (CTXs), potent neurotoxins produced by dinoflagellates of the genera Gambierdiscus and Fukuyoa, accumulate in commonly consumed fish species, causing human ciguatera poisoning. Field collections of Pacific reef fish reveal that consumed CTXs undergo oxidative biotransformations, resulting in numerous, often toxified analogs. Following our study showing rapid CTX accumulation in flesh of an herbivorous fish, we used the same laboratory model to examine the tissue distribution and metabolization of Pacific CTXs following long-term dietary exposure. Naso brevirostris consumed cells of Gambierdiscus polynesiensis in a gel food matrix over 16 weeks at a constant dose rate of 0.36 ng CTX3C equiv g-1 fish d-1. CTX toxicity determination of fish tissues showed CTX activity in all tissues of exposed fish (eight tissues plus the carcass), with the highest concentrations in the spleen. Muscle tissue retained the largest proportion of CTXs, with 44% of the total tissue burden. Moreover, relative to our previous study, we found that larger fish with slower growth rates assimilated a higher proportion of ingested toxin in their flesh (13% vs. 2%). Analysis of muscle extracts revealed the presence of CTX3C and CTX3B as well as a biotransformed product showing the m/z transitions of 2,3-dihydroxyCTX3C. This is the first experimental evidence of oxidative transformation of an algal CTX in a model consumer and known vector of CTX into the fish food web. These findings that the flesh intended for human consumption carries the majority of the toxin load, and that growth rates can influence the relationship between exposure and accumulation, have significant implications in risk assessment and the development of regulatory measures aimed at ensuring seafood safety.

Mitigation of the environment from hazardous pesticides is clamant for all living things. The behavior of the fungicide Fuberidazole was investigated toward biodegradation. Biotransformation experiments were conducted by bacterial strains isolated from soils including, Xanthomonas citri (XC), and Pseudomonas syringae (PS), and fungal strains including, Aspergillus flavus (AF), Aspergillus niger (AN) and Penicillium chrysogenum (PC). Analysis and quantification of Fuberidazole degradation and its metabolites were performed by gas chromatography mass spectrometry and UV-visible spectrophotometry. Pseudomonas syringae and Penicillium chrysogenum displayed great bioremedial potential and degraded 91 and 86% of Fuberidazole after 35 days. Significant metabolites such as Benzimidazole 2-carboxylic acid, Benzimidazole, and 1-(1H-benzimidazole-2-yl)ethanone were produced in the current experiment. The increasing order of half-life for all strains was obtained as, PS (10.3) < PC (10.6) < AN (11) < AF (11.9) = XC (11.9) days. Experimental results demonstrated the capability of bacterial cells to efficiently utilize Fuberidazole as a nutrition source and the significance of favorable environmental conditions for its dissipation.

Abstract Background Rapid utilization of natural resources and other anthropogenic activities intruded heavy metals into the food chain and raised alarming concern for all life forms. The available methods proved insufficient in handling waste and pollutants due to the high cost and generation of toxic residues. Bioremediation strategies have offered sustainable solutions for toxic pollutants. In the current study, cadmium and lead (Cd and Pb respectively) tolerant strains have been isolated from industrial effluent and characterized for tolerance towards target pollutants. The strain was identified by 16s rRNA gene and further used for metal removal from the industrial effluents. Results Bacterial isolates were obtained from industrial discharge and evaluated for their tolerance towards Cd and Pb. AS-1 bacterial isolate exhibited maximum tolerance towards both the metals and hence was selected for further study. The isolate was identified as Staphylococcus epidermidis. ICP-MS and energy dispersive X-ray (EDX) analysis of biomass revealed that a significant proportion of cadmium (90.89%) and lead (94.87%) available in effluent were sequestered within bacterial biomass. Characteristic peaks at 2Ɵ (31.8637 and 45.6247 for cadmium) and (21.0397, 27.0127, 46.0537, 54.2707 and 75.6547 for lead) confirmed the crystalline nature of the sequestered metals. The selected strain was characterized on biochemical and molecular basis and was found to be Staphylococcus epidermidis. Based on 16 S rDNA sequence analysis, a phylogenetic dendrogram was created for the maximum likelihood of the bacterial strain. The sequence was deposited in the NCBI repository (accession number PP587422). Conclusion The work has shown the possible way out of heavy metal pollution sustainably. To the best of the author’s knowledge, this is the first report on the sequestration and reduction of cadmium and lead by a nonpathogenic strain of Staphylococcus epidermidis AS-1 that may be useful for alleviating heavy metal contamination.

Since ancient times, humans have turned to medicinal plants for treating various ailments and curing specific diseases, as these natural plants serve as the primary source of a range of phytochemicals, including triterpenes. Maslinic acid (MA), also known as (2α,3β)-2,3-dihydroxyolean-12-en-28-oic acid, is a pentacyclic triterpene acid present in numerous plants including olive, known for its high safety profile in humans. Recent experimental data increasingly suggests that MA exhibits diverse biological properties and therapeutic effects on various organ diseases, highlighting its significant potential for clinical applications due to its diverse potential pharmacological activities that promote health and resist various diseases, such as hypoglycemic, neuroprotective, anti-tumor, anti-inflammatory, antioxidant and multiple other biological activities. However, the undesirable pharmacokinetic properties of MA, such as high lipophilicity, pose a limitation to its application and development, impacting its bioavailability. Consequently, extensive research spanning decades has focused on structurally modifying MA to overcome these limitations and enhance its pharmacokinetic and therapeutic characteristics, leading to the identification of several potential lead compounds. In this review, we focus on the progress of research in recent years on MA with interest to its chemical and enzymatic modifications as well as the relationships between the modified structures or derivatives and their biological activities.

The research deals with the isoflavone genistein production, followed by the β-glucosidase production from Aspergillus oryzae. The Cajanus cajan leaf extract was prepared and the optimized extraction parameters were leaf powder weight (1 g), agitation time (75 min), and temperature (60°C). The optimal conditions for β-glucosidase production by submerged fermentation were 0.4% (w/v) (NH4)2SO4 as nitrogen source, 0.05% (w/v) MgSO4 as magnesium source, 2 ml (v/v) size of inoculum, and 60 min incubation time. The Al2O3 nanocrystals (NCs) were synthesized by optimal volume of leaf extract (25 ml) and procurement period (50 min) along with Al2NO3 and NaOH. The β-glucosidase immobilization on Al2O3 NCs improved the specific activity from 2.38 ± 0.002 to 5.64 ± 0.07 U·mg−1. The maximum genistein production was achieved with the rate of biotransformation (48 h) and enzyme concentration (1% (v/v)) along with the substrate level. In fourier transform infrared spectroscopy analysis, the difference between both β-glucosidases free and Al2O3 immobilized was obtained with peaks at 1,120 and 2,150 cm−1. The X-ray diffraction analysis for the NCs was obtained from 10° to 80° with several intensities. and zeta potential size distribution was recorded at 16.2% of intensity with 206.4 d nm. After immobilization, the stability of the β-glucosidase was increased, thereby increasing its potential in the pharmaceutical, biofuel, food, and beverage industries.

Abstract The present study revealed the consequences of the interaction of a widely used bioinsecticide and endophyte Metarhizium anisopliae with the hazardous mycotoxin zearalenone (ZEN) as a pure substance and with ZEN as a native component of a crude Fusarium extract. In the environment, microorganisms encounter a mixture of metabolites secreted by other organisms living in the same area, not single substances. The obtained results suggest that M. anisopliae, exposed to a variety of active substances produced by Fusarium graminearum, is able to eliminate ZEN. Within 14 days, M. anisopliae biotransformed 90.8% and 85.8% of ZEN as a pure substance and ZEN as a native component of the F. graminearum extract from Rice Medium (E-Fg-RM), respectively, through reduction predominantly to α-epimers of zearalenols and zearalanols, considered more estrogenic than ZEN, which can raise concerns. Compared to pure ZEN, E-Fg-RM significantly affected the production of Metarhizium secondary metabolites by increasing the destruxins amount by approximately 20–25% and reducing the swainsonine content by 96.2%. All these findings provide a possible picture of the interaction of M. anisopliae with ZEN in the wild, mainly as a result of the use of crude extract from Fusarium, which contained a mixture of different metabolites.

Abstract Black soldier fly larvae (BSFL) could convert a variety of organic wastes, including spent mushroom substrate (SMS) and wet distiller’s grains (WDG). Nevertheless, little is known about the conversion of these wastes by BSFL. Thus, this study investigates the conversion of SMS and WDG in five different proportions by BSFL. This study demonstrates that BSFL can convert SMS, WDG, and their mixtures. It can also encourage the humification of the substrate, increasing the amount of element in the residues. It is evident that there were differences in the carbon and nitrogen element fractionation mode as well as the microbial community present in the residue. The microbial community of the substrate and the physiochemical parameters are intimately related to this. Although the mixture treated with BSFL helps to generate a residue with more humus, it might not be stable.

Paralytic shellfish toxins (PSTs) are a class of neurotoxic marine biotoxins that are widely distributed and cause more than 2, 000 poisoning events worldwide each year, with mortality rates of up to 15%. PSTs can accumulate through the food chain and are mainly distributed in marine organisms such as bivalve mollusks. Several countries and regions, including the European Union, China, and the United States, have established strict regulatory limits (400 MU/100 g or 800 μg STXeq/kg) for PSTs and implemented monitoring programs. As reported previously, factors such as filtration rate, selective feeding, and the efficiency of the organism in absorbing toxin-producing algae can significantly affect the accumulation of PSTs in bivalve mollusks. Mytilus unguiculatus is one of three major commercial mussel species in China, with important economic value and social impact. Due to its high nutritional value, it is extensively cultured as an important shellfish species in the Zhoushan archipelago of Zhejiang Province in China. Alexandrium spp. are the main toxin-producing algae in the area. PSTs have been detected in mussels between May and July after harmful algal blooms. Research into the elimination characteristics of PSTs accumulation in M. unguiculatus is urgently needed to establish a monitoring and control program.In this study, 760 mussels were randomly selected and fed A. catenella at different cell densities, with a high-density group (7.00×105 cells/d), a low-density group (2.80×105 cells/d), and a control group. The experimental period lasted for 30 d, during which the accumulation period approximately represented days 1–7 and the elimination period days 8–30 d. A total of 14 sampling points were set up on days 0.5, 1, 2, 4, 6, and 7 of the accumulation period and days 1, 3, 5, 7, 11, 15, 19, and 23 of the elimination period. Six mussels were randomly collected at each sampling point and dissected into soft tissues, hepatopancreas, and edible tissues. Liquid chromatography-tandem mass spectrometry was used to determine the content of PSTs. During the accumulation period, 5 mL culturing seawater was collected during or 1 h after feeding, and Ruge's solution was added. The filtration rate of the mussels was determined by counting the quantity of A. catenella cells in the water. The results showed that the toxins in M. unguiculatus were not equally distributed. The highest PST content in hepatopancreas tissues was 7, 458.2 μg STXeq/kg (high-density group) and 2, 555.9 μg STXeq/kg (low-density group). The highest PST content in edible tissues was 108.6 μg STXeq/kg (high-density group). The hepatopancreas was identified as a target organ for toxin accumulation. From day 3 to day 7, the filtration rate of mussels decreased, eventually reaching 30% of its initial value. The filtration rate of M. unguiculatus in the high-density group was not significantly different from that of the low-density group during days 1–5 and was significantly lower during days 5–7. During the elimination phase, the PST elimination rate in mussels was 18.4% (hepatopancreas), 18.1% (soft tissues), and 13.1% (edible tissues). At day 30, the residual content of PSTs in the hepatopancreas of mussels was approximately 1 400 μg STXeq/kg in the high-density group and 600.0 μg STXeq/kg in the low-density group. Changes in the proportion of each PST component were transferred from A. catenella to M. unguiculatus. The proportion of C2 was significantly reduced from 74.1% (A. catenella) to 22.6% (high-density group) and 17.1% (low-density group) (P < 0.05); the percentage of C1 increased from 10.6% (A. catenella) to 54.1% (high-density group) and 54.0% (low-density group) (P < 0.05). No significant difference was observed in the percentage of GTX5 between A. catenella and mussels in the different density groups (P > 0.05). No significant conversion was observed between the PST components in the hepatopancreas of mussels throughout the experiment.Our data indicate that the daily accumulation rate of PSTs in M. unguiculatus was lower than that in other mussels. Moreover, the toxin elimination rate was higher than that of other mussels. A negative correlation was observed between the filtration rate of M. unguiculatus and the PST content of each tissue type. These results show that M. unguiculatus is more sensitive to PSTs than other mussels. During the stage of PST transfer from A. catenella to M. unguiculatus, a high proportion of C2 toxin was converted to C1 toxin. After accumulating in the hepatopancreas, the PST profile exhibited relatively stable performance. In summary, we conclude that, due to higher susceptibility to toxins and lower conversion rates, a lower risk is associated with the consumption of M. unguiculatus than with that of other mussels. Our findings will contribute to improving our understanding of the mechanisms underlying the PST accumulation risk in M. unguiculatus and provide valuable scientific insights for developing prevention and risk management strategies concerning PSTs.

Subsurface treatment systems, such as constructed wetlands, riverbank filtration systems, and managed aquifer recharge systems, offer a low-cost means of removing trace organic contaminants from treated municipal wastewater. To assess the processes through which trace organic contaminants are removed in subsurface treatment systems, pharmaceuticals and several major metabolites were measured in porewater, sediment, and plants within a horizontal levee (i.e., a subsurface flow wetland that receives treated municipal wastewater). Concentrations of trace organic contaminants in each wetland compartment rapidly declined along the flow path. Mass balance calculations, analysis of transformation products, microcosm experiments, and one-dimensional transport modeling demonstrated that more than 60% of the contaminant removal could be attributed to transformation. Monitoring of the system with and without nitrate in the wetland inflow indicated that relatively biodegradable trace organic contaminants, such as acyclovir and metoprolol, were rapidly transformed under both operating conditions. Trace organic contaminants that are normally persistent in biological treatment systems (e.g., sulfamethoxazole and carbamazepine) were removed only when Fe(III)- and sulfate-reducing conditions were observed. Minor structural modifications to trace organic contaminants (e.g., hydroxylation) altered the pathways and extents of trace organic contaminant transformation under different redox conditions. These findings indicate that subsurface treatment systems can be designed to remove both labile and persistent trace organic contaminants via transformation if they are designed and operated in a manner that results in sulfate-and Fe(III)-reducing conditions.

Microbial biotransformation of argentatin A (1), isoargentatin A (2) and argentatin B (3), the cycloartane- and lanostane-type triterpenoid constituents of guayule (Parthenium argentatum) resin, with Cunninghamella elegans ATCC 9245-A0 afforded eight new metabolites 4–11. These were identified as products formed as a result of: (i) α- and β-hydroxylation at C-7 and C-11; (ii) sequential oxidation of these newly formed alcohols to their corresponding carbonyl analogues; and (iii) rearrangement of the 9(10)-cyclopropane ring. The observed regiospecific hydroxylation reactions are possibly catalyzed by cytochrome P450 enzymes known to be produced by C. elegans. It is interesting that among the biotransformation products 9–11 of argentatin B (3) with a carbonyl group at C-11, only 11 had resulted from the rearrangement of the 9(10)-cyclopropane ring under the conditions used for biotransformation. This constitutes the first report of biotransformation of argentatins by C. elegans. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to produce an engineered recombinant laccase from extremophilic Halalkalibacterium halodurans C-125 (Lac-HhC-125) with higher protein yield, into a more active conformation and with properties that meet the fundamental needs of biotechnological application. Results: The rLac-HhC125 was partially purified by size exclusion chromatography and concentrated by ultrafiltration (10 kDa) with a yield of 57.6%. Oxidation reactions showed that adding 2 mM CuSO4 to the assay solution led to activating the laccase. To increase its initial activity, the rLac-HhC125 was treated at 50 °C for 20 min before the assays, improving its performance by fourfold using the syringaldazine as a substrate. When treated with EDTA, methanol, ethanol, and DMSO, the rLac-HhC125 maintained more than 80% of its original activity. Interestingly, the acetonitrile induced a twofold activity of the rLac-HhC125. The putative rLac-HhC125 demonstrated a capability of efficient transformation of different organic compounds at pH 6, known as dye precursors, into coloured molecules. Conclusion: The rLac-HhC125 was active at high temperatures and alkaline pH, exhibited tolerance to organic solvents, and efficiently transformed different hydroxy derivatives into coloured compounds, which indicates that it can be used in various biotechnological processes. [ABSTRACT FROM AUTHOR]

Amides are an important type of synthetic intermediate used in the chemical, agrochemical, pharmaceutical, and nutraceutical industries. The traditional chemical process of converting nitriles into the corresponding amides is feasible but is restricted because of the harsh conditions required. In recent decades, nitrile hydratase (NHase, EC 4.2.1.84) has attracted considerable attention because of its application in nitrile transformation as a prominent biocatalyst. In this review, we provide a comprehensive survey of recent advances in NHase research in terms of natural distribution, enzyme screening, and molecular modification on the basis of its characteristics and catalytic mechanism. Additionally, industrial applications and recent significant biotechnology advances in NHase bioengineering and immobilization techniques are systematically summarized. Moreover, the current challenges and future perspectives for its further development in industrial applications for green chemistry were also discussed. This study contributes to the current state-of-the-art, providing important technical information for new NHase applications in manufacturing industries. [ABSTRACT FROM AUTHOR]

Abstract A biotransformation pair consisting of vinblastine: vincristine present in the Catharanthus roseus plant is of immense pharmacological significance. In this study, we successfully transformed vinblastine into vincristine outside the plant using Pseudomonas aeruginosa 8485 and Pseudomonas fluorescens 2421 and evaluated the antiangiogenic potential of thus produced vincristine through the CAM assay. The toxicity assay showed that both Pseudomonas spp. can tolerate varying concentrations (25–100 µl of 1 mg/ml) of vinblastine. The biotransformation was performed in a liquid nutrient broth medium containing vinblastine (25–100 µl), and Pseudomonas spp. inoculums (50–150 µl) by incubating at 30 °C and 37 °C, respectively for 8 days. The process was optimized for substrate and culture concentrations, pH, temperature, and rotation speed (rpm) for the highest conversion. Analysis using LC–MS/MS confirmed the presence of vincristine as a product of the vinblastine biotransformation by two Pseudomonas spp. P. fluorescens 2421 showed a faster conversion rate with 95% of vinblastine transformed within 24 h than P. aeruginosa 8485, which demonstrated a conversion rate of 92% on the 8th day. From LC–MS/MS analysis, the optimal conditions for the reaction were determined as vinblastine (25 µl), microbial inoculums (150 µl or 200 × 106 and 210 × 106 CFU/ml), pH 7.4, rotation speed of 180 rpm, and temperatures of 30 °C and 37 °C with incubation time of 8 days. The vincristine produced exhibited potent antiangiogenic activity in the CAM assay reducing the thickness and branching of blood vessels in a dose-dependent manner. The study concludes that both Pseudomonas spp. showed promise for vincristine production from vinblastine, without compromising its antiangiogenic properties.

Abstract Biotransformation is a process in which molecules are modified in the presence of a biocatalyst or enzymes, as well as the metabolic alterations that occur in organisms from exposure to the molecules. Microbial biotransformation is an important process in natural product drug discovery as novel compounds are biosynthesised. Additionally, biotransformation products offer compounds with improved efficacy, solubility, reduced cytotoxic and allows for the understanding of structure activity relationships. One of the driving forces for these impeccable findings are associated with the presence of cytochrome P450 monooxygenases that is present in all organisms such as mammals, bacteria, and fungi. Numerous fungal strains have been used and reported for their ability to biotransform different compounds. This review focused on studies using Alternaria species as biocatalysts in the biotransformation of natural product compounds. Alternaria species facilitates reactions that favour stereoselectivity, regioselectivity under mild conditions. Additionally, microbial biotransformation products, their application in food, pharmaceutical and agricultural sector is discussed in this review. Graphical Abstract