A Novel Benzopyrone Derivative from Streptomyces chrestomyceticus ADP4 Inhibits Growth and Virulence Factors of Candida albicans.

Abstract

Antimicrobial resistance (AMR) poses a serious threat to human health globally. Expeditious discovery and development of new drugs has become indispensable for addressing this challenge. In this context, a novel benzopyrone derivative, designated as 82B1, has been isolated from S. chrestomyceticus strain ADP4. This compound exhibited significant inhibitory activity against different Candida species including C. albicans, C. tropicalis, C. krusei, C. parapsilosis and C. auris with minimum inhibitory concentration (MIC₉₀) values in the concentration range of 25-125 µg/mL. The structure of 82B1 was elucidated through analyses of the spectral data obtained using liquid chromatography-tandem mass spectrometry (LCMS/MS), Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared Spectroscopy (FTIR) and Ultraviolet (UV) spectroscopy, that led to its identity as 7, 13, 14-trihydroxy-6H-benzo-[c]-chromen-6-one8-[1'β-carboxycyclopentanyl]-2'β-[8'β-ethylcyclopentane]. It significantly inhibited the major virulence factors of C. albicans such as yeast to hyphae transition, biofilm formation, and secretion of hydrolytic enzymes at its subinhibitory concentrations. It did not display cytotoxicity on human hepatoblastoma cell line (HepG2 cells), signifying its potential as a candidate for anti-Candida drug development.