Inhibition of biofilm formation in Mycobacterium smegmatis by extracts of endophytic fungi from Poikilospermum suaveolens (Blume) Merr)

Abstract

Abstract Tuberculosis (TB) is the most common and lethal infectious illness on the planet, and it is still a global epidemic. Despite treatment options, this condition, caused by Mycobacterium tuberculosis. Surrogate organism Mycobacterium smegmatis is employed in antimycobacterial drug development tests. Mycobacteria, particularly Mycobacterium smegmatis, have been found to proliferate in biofilms. The goal of this study was to explore how a bioactive component from endophytic fungi affects M. smegmatis, specifically its growth and biofilm habits, to establish a scientific foundation for its medicinal use. After identification of endophytic fungi, the bioactive fraction were tested for antimycobacterial properties, MIC, IC50, and inhibition of biofilm. Screening for effective inhibitors of M. smegmatis growth and biofilm assembly was conducted using the micro-broth dilution technique. After measuring biofilm density with crystal violet stain and a spectrophotometer, the study examined the combined impact of the top-performing extract and rifampicin. DNA analysis identified the endophytic fungus 04BhSi1-1 as Fusarium oxysporum. Out of the three purified fractions, fraction 1 exhibited the most potent antimycobacterial properties with a minimum inhibitory concentration of 12.5 µg/mL and was uniquely effective at preventing biofilm growth. The synergy between this extract and rifampicin enhanced the inhibition, indicating that F. oxysporum derived from Poikilospermum suaveolens is a promising candidate for future drug discovery.