Ustisorbicillinols G and H, Two New Antibacterial Sorbicillinoids from the Albino Strain LN02 of Rice False Smut Fungus <i>Villosiclava virens</i>

<i>Villosiclava virens</i> (anamorph: <i>Ustilaginoidea virens</i>), the causal fungal pathogen of rice false smut, has been found to produce various secondary metabolites. The albino strain LN02 is a natural albino phenotype mutant of <i>V. virens</i> due to its...

Full description

Saved in:
Bibliographic Details
Main Authors: Xuwen Hou, Mengyao Xue, Gan Gu, Dan Xu, Daowan Lai, Ligang Zhou
Format: Article
Language:English
Published: MDPI AG 2025-07-01
Series:Molecules
Subjects:
Online Access:https://www.mdpi.com/1420-3049/30/14/3039
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:<i>Villosiclava virens</i> (anamorph: <i>Ustilaginoidea virens</i>), the causal fungal pathogen of rice false smut, has been found to produce various secondary metabolites. The albino strain LN02 is a natural albino phenotype mutant of <i>V. virens</i> due to its inability to produce ustilaginoidins. The fermentation of <i>V. virens</i> LN02 was performed in solid rice medium to obtain fungal cultures, which were chemically investigated. After removing the known metabolites, two new dimeric sorbicillinoids, namely ustisorbicillinols G (<b>1</b>) and H (<b>2</b>), were isolated from the ethyl acetate extract. Their structures were elucidated using spectroscopic data analyses and quantum chemical calculations. Compounds <b>1</b> and <b>2</b> displayed antibacterial activity towards <i>Ralstonia solanacearum</i>, <i>Agrobacterium tumefaciens</i> and <i>Bacillus subtilis</i>, with median inhibitory concentration (IC<sub>50</sub>) values of 19.76–25.43 μg/mL for <b>1</b> and 25.35–45.48 μg/mL for <b>2</b>. The discovery of new sorbicillinoids will increase the diversity of the secondary metabolites of <i>V. virens</i> and provide candidates for the creation of new antimicrobials as well.
ISSN:1420-3049