Bioorg Chem
December 2024
Promoting endogenous neurogenesis for brain repair is emerging as a promising strategy to mitigate the functional impairments associated with various neurological disorders characterized by neuronal death. Diterpenes featuring tigliane, ingenane, jatrophane and lathyrane skeletons, frequently found in Euphorbia plant species, are known protein kinase C (PKC) activators and exhibit a wide variety of pharmacological properties, including the stimulation of neurogenesis. Microbial transformation of these diterpenes represents a green and sustainable methodology that offers a hitherto little explored approach to obtaining novel derivatives and exploring structure-activity relationships.
View Article and Find Full Text PDFPremyrsinane-type diterpenoids have been considered to originate from the cyclization of a suitable 5,6- or 6,17-epoxylathyrane precursor. Their biological activities have not been sufficiently explored to date, so the development of synthetic or microbial approaches for the preparation of new derivatives would be desirable. Epoxyboetirane A () is an 6,17-epoxylathyrane isolated from in a large enough amount to be used in semi-synthesis.
View Article and Find Full Text PDFLathyrane-type diterpenes have a wide range of biological activities. Among them, euphoboetirane A () exerts neurogenesis-promoting activity. In order to increase the structural diversity of this type of lathyrane and explore its potential use in neurodegenerative disorders, the biotransformation of by BC-5GB.
View Article and Find Full Text PDFThe fungal strain BC17 was isolated from sediments collected in the intertidal zone of the inner Bay of Cadiz and characterized as . On the basis of the one strain-many compounds (OSMAC) approach, four new eremophilane-type sesquiterpenes (-), together with thirteen known derivatives (-) and two reported diketopiperazines (, ), were isolated from this strain. The chemical structures and absolute configurations of the new compounds were determined through extensive NMR and HRESIMS spectroscopic studies and ECD calculation.
View Article and Find Full Text PDFMarine microorganisms account for over 90% of ocean biomass and their diversity is believed to be the result of their ability to adapt to extreme conditions of the marine environment. Biotransformations are used to produce a wide range of high-added value materials, and marine-derived fungi have proven to be a source of new enzymes, even for activities not previously discovered. This review focuses on biotransformations by fungi from marine environments, including bioremediation, from the standpoint of the chemical structure of the substrate, and covers up to September 2022.
View Article and Find Full Text PDFChemical epigenetic manipulation of Botrytis cinerea strain B05.10 with the histone deacetylase inhibitor SAHA led to the isolation of a new cryptic metabolite, botrycinereic acid (22a). This compound was also overproduced by inactivating the stc2 gene, which encodes an unknown sesquiterpene cyclase.
View Article and Find Full Text PDFMarine microorganisms have proven to be a source of new natural products with a wide spectrum of biological activities relevant in different industrial sectors. The ever-increasing number of sequenced microbial genomes has highlighted a discrepancy between the number of gene clusters potentially encoding the production of natural products and the actual number of chemically characterized metabolites for a given microorganism. Homologous and heterologous expression of these biosynthetic genes, which are often silent under experimental laboratory culture conditions, may lead to the discovery of new cryptic natural products of medical and biotechnological interest.
View Article and Find Full Text PDFClovane and isocaryolane derivatives have been proven to show several levels of activity against the phytopathogenic fungus . Both classes of sesquiterpenes are reminiscent of biosynthetic intermediates of botrydial, a virulence factor of . Further development of both classes of antifungal agent requires exploration of the structure-activity relationships for the antifungal effects on and phytotoxic effects on a model crop.
View Article and Find Full Text PDFBotrytis cinerea has high potential for the production of specialized metabolites. The recent resequencing of the genome of the B05.10 strain using PacBio technology and the resulting update of the Ensembl Fungi (2017) database in the genome sequence have been instrumental in identifying new genes that could be involved in secondary metabolism.
View Article and Find Full Text PDFA small library of phorbol 12,13-diesters bearing low lipophilicity ester chains was prepared as potential neurogenic agents in the adult brain. They were also used in a targeted UHPLC-HRMS screening of the latex of . Two new 12-deoxy-16-hydroxyphorbol 13,16-diesters were isolated, and their structures were deduced using two-dimensional NMR spectroscopy and NOE experiments.
View Article and Find Full Text PDFLathyrane-type diterpenes previously have been proven to promote proliferation of neural precursor cells (NPCs) by targeting and activating one or more protein kinase C (PKC) isozymes. Aiming to find new drug candidates with a lathyrane skeleton to modulate adult neurogenesis through PKC activation, a phytochemical study of a methanol extract of the aerial parts of was carried out. Seven new diterpenes, representing the premyrsinane (-), myrsinane (, ), and cyclomyrsinane types (, ), along with three known diterpenes, belonging to the cyclomyrsinane () and lathyrane types (, ), were isolated.
View Article and Find Full Text PDFPatulin (1) is a mycotoxin contaminant in fruit and vegetable products worldwide. Biocontrol agents, such as the yeast Rhodotorula kratochvilovae strain LS11, can reduce patulin (1) contamination in food. R.
View Article and Find Full Text PDFA 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.
View Article and Find Full Text PDFThe sequencing of the genomes of the B05.10 and T4 strains of the fungus Botrytis cinerea revealed an abundance of novel biosynthetic gene clusters, the majority of which were unexpected on the basis of the previous analyses of the fermentation of these and closely related species. By systematic alteration of easy accessible cultivation parameters, using chemical induction with copper sulfate, we have found a cryptic sesquiterpenoid family with new structures related to eremophil-9-ene, which had the basic structure of the sesquiterpene (+)-5-epiaristolochene ((+)-4-epieremophil-9-ene).
View Article and Find Full Text PDFResearch has been conducted on the biotransformation of (8S,9R)-isocaryolan-9-ol (4a) and (1S,2S,5R,8S)-8-methylene-1,4,4-trimethyltricyclo[6.2.1.
View Article and Find Full Text PDFIsotopic labelling experiments and the study of mutants with disrupted genes encoding botcinic acid have revealed a common link in the biosynthesis of the polyketide toxins excreted by Botrytis cinerea: botcinins and botrylactones. Furthermore, the results reported here shed light on the origin of the starter unit, thereby solving a long-standing mystery in the biosynthesis of botcinins.
View Article and Find Full Text PDFThe infection of stored apples by the fungus Penicillium expansum causes the contamination of fruits and fruit-derived products with the mycotoxin patulin, which is a major issue in food safety. Fungal attack can be prevented by beneficial microorganisms, so-called biocontrol agents. Previous time-course thin layer chromatography analyses showed that the aerobic incubation of patulin with the biocontrol yeast Rhodosporidium kratochvilovae strain LS11 leads to the disappearance of the mycotoxin spot and the parallel emergence of two new spots, one of which disappears over time.
View Article and Find Full Text PDFThe metabolism of the fungistatic agent (8R,9R)-8-methoxyisocaryolan-9-ol (4) by the fungus Botrytis cinerea has been investigated. Biotransformation of compound 4 yielded compounds 5 and 6-9. No dihydrobotrydial is observed after 4 days of incubation of compound 4.
View Article and Find Full Text PDFSix new azaphilones, 5'-epichaetoviridin A (7), 4'-epichaetoviridin F (9), 12β-hydroxychaetoviridin C (10), and chaetoviridins G-I (11-13), and six known azaphilones, chaetoviridins A-E (1-5) and 4'-epichaetoviridin A (8), were isolated from the endophytic fungus Chaetomium globosum cultivated in PDB medium for 21 days. The structure elucidation and the assignment of the relative configurations of the new natural products were based on detailed NMR and MS spectroscopic analyses. The structure of compound 1 was confirmed by single-crystal X-ray diffraction analysis.
View Article and Find Full Text PDFGroup 4 and 5 metallocenes, Cp(2)TiCl(2), Cp(2)ZrCl(2) and Cp(2)VCl(2), have been evaluated as catalyst in the solvent free, room temperature, preparation of vicinal aminoalcohols. The regioselectivity of the reaction and the fungistatic activity of the prepared compounds against Botrytis cinerea and Colletotrichum gloeosporioides are discussed.
View Article and Find Full Text PDFDiketopiperazine (DKP) derivatives, named colletopiperazine, fusaperazine C and E as well as four known DKPs were isolated from cultures of Colletotrichum gloeosporioides, Penicillium crustosum, both endophytic fungi isolated from Viguiera robusta, and a Fusarium spp., an endophyte of Viguiera arenaria, respectively. Their structures were established on the basis of their spectroscopic data.
View Article and Find Full Text PDF[reaction: see text] The biosynthetic origin of the botcinolide skeleton was investigated by means of feeding 13C- and 2H-labeled precursors to Botrytis cinerea. Three new compounds, two homobotcinolide derivatives, 3-O-acetylhomobotcinolide (5) and 8-methylhomobotcinolide (6), and a new 11-membered lactone (7), were isolated. Their structures were elucidated on the basis of spectroscopic data, including one-bond and long-range 1H-13C correlations.
View Article and Find Full Text PDF