Endophytic Fungi from Asparagus Racemosus: A New Source of Antimicrobial and Antioxidant Compounds

Abstract

The current study explores endophytic fungi isolated from Asparagus racemosus roots, focusing on its antimicrobial and antioxidant activity. A total of twenty four fungal strains were isolated and screened against seven pathogenic microbes (Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Streptococcus entericus, Escherichia coli, Candida albicans, and Aspergillus niger). The endophytic fungus, S-32 exhibited the highest antimicrobial activity, against all tested pathogens. The DPPH assay revealed that endophytic fungus S-5, had the strongest effect with an IC50 value of 4.4 (µg/µl) and the highest antioxidant activity index (AAI) of 1.7. High-performance liquid chromatography (HPLC) was used to analyze the saponin concentration in the extracts of endophytic fungi S-32 (2174.95 ng/mg) and S-5 (1244.558 ng/mg). The analysis of 18S rRNA sequencing revealed that S-32 and S-5 were identified as Aspergillus terreus and Aspergillus oryzae respectively.