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A thorough study of the fermentation broth of three strains of Botrytis cinerea which were grown on a modified Czapek-Dox medium supplemented with 5 ppm copper sulphate, yielded five undescribed metabolites. These metabolites possessed a sesquiterpenoid (+)-4-epi-eremophil-9-ene carbon skeleton which was enantiomeric to that of the phytoalexin, capsidiol. The isolation of these metabolites when the fungus was stressed, suggests that they may be potential effectors used by B. cinerea to circumvent plant chemical defences against phytopathogenic fungi. The biosynthesis of these compounds has been studied using 2 H and 13 C labelled acetate., (Copyright © 2018. Published by Elsevier Ltd.)

Background and Objectives: β-Lapachone is a drug candidate in phase II clinical trials for treatment of solid tumors. The therapeutic efficacy of β-lapachone is closely related to its metabolism, since this o-naphthoquinone produces cytotoxic effect after intracellular bioreduction by reactive oxygen species formation. The aim of this study was to produce β-lapachone human blood phase I metabolites to evaluate their cytotoxic activities., Methods: The biotransformation of β-lapachone was performed using Mucor rouxii NRRL 1894 and Papulaspora immersa SS13. The metabolites were isolated and their chemical structures determined from spectrometric and spectroscopic data. Cell cytotoxicity assays were carried out with β-lapachone and its metabolites using the neoplastic cell line SKBR-3 derived from human breast cancer and normal human fibroblast cell line GM07492-A., Results: Microbial transformation of β-lapachone by filamentous fungi resulted in the production of five metabolites identical to those found during human blood metabolism, a novel metabolite and a product stated before only in a synthetic procedure. The analysis of the results showed that β-lapachone metabolites were not cytotoxic for the neoplastic cell line SKBR-3 derived from human breast cancer and the normal human fibroblast cell line GM07492-A. The cytotoxic activity assay against the neoplastic cell line SKBR-3 revealed that the lowest half-maximal inhibitory concentration (IC 50 ) values of these β-lapachone metabolites were 33- to 52-fold greater than IC 50 values of β-lapachone., Conclusions: The cytotoxic activity of β-lapachone in vivo may be reduced due to its swift conversion in blood.

Due to the severity and high prevalence of allergic diseases, there is growing interest in the development of inhibitors of such conditions. 3-Arylcoumarin derivatives emerge as promising compounds for the treatment of allergic disorders, in particular due to their close structural similarity to flavonoids, whose anti-allergic activity has been extensively reported. The aim of this work was to perform a screening of a set of 3-arylcoumarins as potential inhibitors of mast cell degranulation, a key event for the development of allergic reactions. For that purpose, it was utilized a biosensor model based on mast cells, whose in vitro assay allows for such screening, in a high throughput fashion, and also permits bringing to attention some coumarin structural features that are important for their biological activity. The mast cell-based biosensor was shown to discriminate, with high sensitivity and reproducibility, between coumarins that did not affect or caused different degrees of inhibition of degranulation. Among active coumarins, some substituents could be accounted for their inhibitory activity, such as the hydroxylation of positions 6 and 2' of 3-phenylcoumarins, in addition to catechol, amino and thiophene moieties. In summary, 3-arylcoumarins could be suggested as potential candidates for the development of new anti-allergic drugs.

Mast cells (MCs) are bone-marrow-derived haematopoietic cells that are widely distributed in human tissues. When activated, they will release tryptase, histamine and other mediators that play major roles in a diverse array of diseases/disorders, including allergies, inflammation, cardiovascular diseases, autoimmune diseases, cancers and even death. The multiple pathological effects of MCs have made their stabilizers a research hotspot for the treatment of related diseases. To date, the clinically available MC stabilizers are limited. Considering the rapidly increasing incidence rate and widespread prevalence of MC-related diseases, a comprehensive reference is needed for the clinicians or researchers to identify and choose efficacious MC stabilizers. This review analyzes the mechanism of MC activation, and summarizes the progress made so far in the development of MC stabilizers. MC stabilizers are classified by the action mechanism here, including acting on cell surface receptors, disturbing signal transduction pathways and interfering exocytosis systems. Particular emphasis is placed on the clinical applications and the future development direction of MC stabilizers. [ABSTRACT FROM AUTHOR]

Covering: September 1964 to June 2023 Bacteria and fungi living in symbiosis with insects have been studied over the last sixty years and found to be important sources of bioactive natural products. Not only classic producers of secondary metabolites such as Streptomyces and other members of the phylum Actinobacteria but also numerous bacteria from the phyla Proteobacteria and Firmicutes and an impressive array of fungi (usually pathogenic) serve as the source of a structurally diverse number of small molecules with important biological activities including antimicrobial, cytotoxic, antiparasitic and specific enzyme inhibitors. The insect niche is often the exclusive provider of microbes producing unique types of biologically active compounds such as gerumycins, pederin, dinactin, and formicamycins. However, numerous insects still have not been described taxonomically, and in most cases, the study of their microbiota is completely unexplored. In this review, we present a comprehensive survey of 553 natural products produced by microorganisms isolated from insects by collating and classifying all the data according to the type of compound (rather than the insect or microbial source). The analysis of the correlations among the metadata related to insects, microbial partners, and their produced compounds provides valuable insights into the intricate dynamics between insects and their symbionts as well as the impact of their metabolites on these relationships. Herein, we focus on the chemical structure, biosynthesis, and biological activities of the most relevant compounds. [ABSTRACT FROM AUTHOR]

In this paper, the NO donor trans-(Cl,Cl)-[Ru(FT)Cl2(NO)]Cl (Ru–NO) was incorporated in a Pluronic F127 (PL)–chitosan (CS) biocompatible hydrogel. Two concentrations were achieved (520 and 13 μg g−1), resulting in hydrogels with sol–gel transition temperatures of around 36–38 °C, according to rheological studies. The presence of the Ru–NO complex did not significantly modify the thermal (DSC) and morphological (AFM) characteristics of the gels. For Ru–NO-embedded hydrogels, nitric oxide photorelease was evidenced at 400 nm. The quantum yield of photorelease was independent of the temperature at which the gel was maintained (25, 31, or 37 °C) and was found to be ca. 0.015. EPR as well as measurements using an electrochemical NO sensor also confirmed NO release upon light irradiation at 400 nm. [ABSTRACT FROM AUTHOR]

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Paeonia lactiflora Pall. is not only a traditional ornamental plant, but also an important medicinal plant. Currently, some P. lactiflora cultivars are used for ornamental purposes, but their potential medicinal value is ignored. To explore the medicinal potential of the ornamental varieties, the medicinal cultivar 'Hangbaishao' (HS) and the ornamental cultivar 'Zifengyu' (ZFY) were selected, and microbiome and metabolome analyses were performed to compare the composition of the endophytes and metabolites in the roots. The diversity and abundance of bacteria were not significantly different between HS and ZFY; however, the diversity and abundance of endophytic fungi in the ornamental cultivar ZFY were much higher than those in the medicinal cultivar HS. The flavonoids and phenolic acid contents of the ornamental cultivar ZFY were significantly higher than those of the medicinal cultivar HS, indicating that ZFY has medicinal value. The differences in root endophytes between HS and ZFY may lead to differences in phenolic acids and flavonoids. To explore the relationship between endophytes and the accumulation of phenolic acids and flavonoids, a joint analyses of the microbiome and metabolome were performed. The key bacterium, Ruminococcaceae bacterium GD7, led to the accumulation of phenolic acids and flavonoids in the ZFY. This study contributes to future research on the potential medicinal value of ornamental P. lactiflora and provides a new approach for realizing the 'dual use of medicine and appreciation' of P. lactiflora. [ABSTRACT FROM AUTHOR]

Endophytes, microorganisms that live in the internal tissues and organs of the plants, are known to produce numerous bioactive compounds, including, at times, some phytochemicals of their host plant. For such reason, endophytes have been quoted as a potential source for discovering bioactive compounds, particularly, of medical interest. Currently, many non-communicable diseases are threatening global human health, noticeably: diabetes, neurodegenerative diseases, cancer, and other ailment related to chronic inflammation and ageing. Intriguingly, the pathogenesis and development of these diseases have been linked to an excessive formation and accumulation of advanced glycation end products (AGEs). AGEs are a heterogeneous group of compounds that can alter the conformation, function, and lifetime of proteins. Therefore, compounds that prevent the formation and consequent accumulation of AGEs (AntiAGEs compounds) could be useful to delay the progress of some chronic diseases, and/or harmful effects of undue AGEs accumulation. Despite the remarkable ability of endophytes to produce bioactive compounds, most of the natural antiAGEs compounds reported in the literature are derived from plants. Accordingly, this work covers 26 plant antiAGEs compounds and some derivatives that have been reported as endophytic metabolites, and discusses the importance, possible advantages, and challenges of using endophytes as a potential source of antiAGEs compounds. [ABSTRACT FROM AUTHOR]

The biotransformation of mulin-11,13-dien-20-oic acid (1), a diterpene isolated from extracts of Azorella compacta was evaluated using Aspergillus alliaceus UI 315 and Mucor circinelloides ATCC 7941. Cultures of A. alliaceus containing 1 produced the known metabolite 16-hydroxy-mulin-11,13-dien-20-oic acid (2) in 19.5% yield; alternatively, biotransformation of 1 by cultures of M. circinelloides produced two new metabolites identified as mulin-11,13-dien-16,20-dioic acid (3) and 7α,13β-dihydroxy-mulin-11-en-20-oic acid (4) on the basis of their spectroscopic data. [ABSTRACT FROM AUTHOR]

Lapachol is a natural naphthoquinone with a range of biological effects, including anticancer activity. Microbial transformations of lapachol can lead to the formation of new biologically active compounds. In addition, fungi can produce secondary metabolites that are also important for drug discovery. The goal of this study was to evaluate the ability of filamentous fungi to biotransform lapachol into biologically active compounds and identify secondary metabolites produced in the presence of lapachol. Seven out of nine strains of filamentous fungi tested exhibited the ability to biotransform or biodegrade lapachol. The bioactive derivatives norlapachol and isolapachol were identified among biotransformation products. Moreover, lapachol stimulated the production of pyrrolo-[1,2-a] pyrazine-1,4-dione, hexahydro-3-(2-methylpropyl) and phenol-2,4-bis-(1,1-dimethylethyl), secondary metabolites already known to have antimicrobial and antioxidant activities. These results open the perspective of using these strains of filamentous fungi for lapachol biotransformation and efficient production of several biologically active compounds. [ABSTRACT FROM AUTHOR]

Hydrolysis of (±)-β-aryl-γ-ethylidene-γ-lactones by fungal strain Aspergillus ochraceus AM370 afforded (−)-(S)-γ-ethylidene-γ-lactones 2a–d and (+)-(R)-γ-ketoacids 3a–d. Enantiomeric purity of the unreacted lactones was strictly related to a size of an aryl substituent at C-4 of γ-lactone ring, with the highest ee (77%) obtained for the (−)-(S)-γ-ethylidene-γ-lactone possessing unsubstituted benzene ring (2a) and the lowest one (15%) determined for the (−)-(S)-γ-ethylidene-γ-lactone with bulky 1,3-benzodioxole system (2d). Lactones 2a–d, both racemic and enantiomerically enriched, as well as products of their hydrolysis showed varying degrees of feeding deterrent activity against lesser mealworm, Alphitobius diaperinus Panzer, which depended on the structure of the compound and the developmental stage of the lesser mealworm. In the case of adults, more active were γ-lactones 2a–d, compared with ketoacids 3a–d. Only in the case of lactone 2a was the effect of configuration of stereogenic center on the activity found. Particularly strong deterrents against this stage (T > 180) were racemic and (−)-(S)-γ-ethylidene-γ-lactone with p-methoxysubstituted phenyl ring (2c). [ABSTRACT FROM AUTHOR]

The aim of the project was to find new catalysts capable of chlorolactone biotransformation. Three bicyclic chlorolactones with structures possessing one or two methyl groups in their cyclohexane ring were subjected to screening biotransformation using seven bacterial strains and one fungal strain from a salt mine. Three strains of bacteria (Micrococcus luteus Pb10, Micrococcus luteus WSP45, Gordonia alkanivorans Pd25) and one fungal strain (Aspergillus sydowii KGJ10) were able to catalyse hydrolytic dehalogenation of one substrate. The classification of the strains that were effective biocatalysts was confirmed by 16S rDNA analysis. The best result (76%) was obtained using Aspergillus sydowii KGJ10. All strains catalysed hydrolytic dehalogenation without changing the conformation. The equatorial position of the chlorine atom in the substrate turned out to be warrant of the positive result of the biotransformation process. [ABSTRACT FROM AUTHOR]

Dehydration of yeast cells causes them to enter a state of anhydrobiosis in which their metabolism is temporarily and reversibly suspended. This unique state among organisms is currently used in the production of active dry yeasts, mainly used in baking and winemaking. In recent decades non-conventional applications of yeast dehydration have been proposed for various modern biotechnologies. This mini-review briefly summarises current information on the application of dry yeasts in traditional and innovative fields. It has been shown that dry yeast preparations can be used for the efficient protection, purification and bioremediation of the environment from heavy metals. The high sorption activity of dehydrated yeasts can be used as an interesting tool in winemaking due to their effects on quality and taste. Dry yeasts are also used in agricultural animal feed. Another interesting application of yeast dehydration is as an additional stage in new methods for the stable immobilisation of microorganisms, especially in cases when biotechnologically important strains have no affinity with the carrier. Such immobilisation methods also provide a new approach for the successful conservation of yeast strains that are very sensitive to dehydration. In addition, the application of dehydration procedures opens up new possibilities for the use of yeast as a model system. Separate sections of this review also discuss possible uses of dry yeasts in biocontrol, bioprotection and biotransformations, in analytical methods as well as in some other areas. [ABSTRACT FROM AUTHOR]

The rising consumer requests for natural flavors and fragrances have generated great interest in the aroma industry to seek new methods to obtain fragrance and flavor compounds naturally. An alternative and attractive route for these compounds is based on bio-transformations. In this review, the application of biocatalysis by Non Conventional Yeasts (NCYs) whole cells for the production of flavor and fragrances is illustrated by a discussion of the production of different class of compounds, namely Aldehydes, Ketones and related compounds, Alcohols, Lactones, Terpenes and Terpenoids, Alkenes, and Phenols. [ABSTRACT FROM AUTHOR]

As part of a program aiming at the selection of yeast strains which might be of interest as sources of natural flavours and fragrances, the bioreduction of (4R)-(-)-carvone and (1R)-(-)-myrtenal by whole-cells of non-conventional yeasts (NCYs) belonging to the genera Candida, Cryptococcus, Debaryomyces, Hanseniaspora, Kazachstania, Kluyveromyces, Lindnera, Nakaseomyces, Vanderwaltozyma and Wickerhamomyces was studied. Volatiles produced were sampled by means of headspace solid-phase microextraction (SPME) and the compounds were analysed and identified by gas chromatography-mass spectroscopy (GC-MS). Yields (expressed as % of biotransformation) varied in dependence of the strain. The reduction of both (4R)-(-)-carvone and (1R)-(-)-myrtenal were catalyzed by some ene-reductases (ERs) and/or carbonyl reductases (CRs), which determined the formation of (1R,4R)-dihydrocarvone and (1R)-myrtenol respectively, as main flavouring products. The potential of NCYs as novel whole-cell biocatalysts for selective biotransformation of electron-poor alkenes for producing flavours and fragrances of industrial interest is discussed. [ABSTRACT FROM AUTHOR]

Genetic variability of Phoma sorghina, a ubiquitous facultative phytopathogen, was investigated on 41 isolates cultivated from surface-sterilized sorghum grains originating from South Africa and Texas; pearl millet isolates from Namibia were also included. Most of the isolates from Texas produced intense red pigments, especially on Czapek-Dox agar plates. Many African isolates formed conspicuous dark radial substrate hyphae with intercalated chlamydospores on oatmeal plates. Conidial dimensions and shape were very variable (mean lengths 4.5–5.7 μm). Haplotypes were defined based on 53 markers from banding patterns obtained with rep-PCR (primers: M13core, ERIC IR). The shared geographic origin was partially reflected in the clades of the haplotype phylogram. The values of G ST were intermediate; 16–37 % of the variation was found between the populations. Nm values of gene flow were 0.84–1.15. Average gene diversity H E was moderate (0.256). Sequences of ITS-rDNA were obtained from 21 isolates. Allele 1 was found in 9 isolates scattered throughout the clades, allele 2 occurred in 6 isolates (5 of them from the same clade), alleles 3 and 4 were shared by two isolates each and two isolates were unique. Alleles 1 and 2 were also found among highly related sequences from GenBank. All shared an 8-bp deletion near the 5′ end of ITS2 that was not found in any other Phoma/ Didymella species and which may be a typical marker for P. sorghina. Among related species, members of legume-associated Ascochyta/ Didymella complex, Epicoccum spp., D. applanata and P. glomerata were found. [ABSTRACT FROM AUTHOR]

Steroid hormones play an essential role in a wide variety of actions in the body, such as in metabolism, inflammation, initiating and maintaining sexual differentiation and reproduction, immune functions, and stress response. Androgen, aromatase, and sulfatase pathway enzymes and nuclear receptors are responsible for steroid biosynthesis and sensing steroid hormones. Changes in steroid homeostasis are associated with many endocrine diseases. Thus, the discovery and development of novel drug candidates require a detailed understanding of the small molecule structure–activity relationship with enzymes and receptors participating in steroid hormone synthesis, signaling, and metabolism. Here, we show that simple coumarin derivatives can be employed to build cost-efficiently a set of molecules that derive essential features that enable easy discovery of selective and high-affinity molecules to target proteins. In addition, these compounds are also potent tool molecules to study the metabolism of any small molecule. [ABSTRACT FROM AUTHOR]