Evaluation of Bioactive Metabolites Isolated from Endophytic Fungus Chaetomium cupreum of the Plant Mussaenda luteola

Abstract

Abstract: Background: Endophytic fungi are one of the most promising resources of natural bioactive products. In the present study, secondary metabolites were isolated from the endophytic fungus Chaetomium cupreum and evaluated in vitro for pharmaceutical potentials. Objective: To characterize the secondary metabolites obtained from the endophytic fungus Chaetomium cupreum from the plant Mussaenda luteola and to determine its antioxidant, cytotoxicity and anti-mycobacterial activities. Methods: Three secondary metabolites were isolated by column chromatography and solvent-solvent fractionation method from the ethyl acetate and methanol extract of C. cupreum. The structures were elucidated by spectroscopic studies includes FT-IR, NMR, MS analysis. Anti-mycobacterial activity of metabolites was determined by Microtitre Plate Alamar Blue Assay (MABA) against Mycobacterium tuberculosis H37Rv (ATCC27294) and also evaluated the antioxidant potentials using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging assay. The cytotoxicity test was performed against breast cancer cell line MCF-7 using MTT assay. Results: Three secondary metabolites were characterized as 6- (heptacosa- 18ˈ Z enyl)- 2- (- 18ˈˈ hydroxyl- 1ˈˈ enyl- 19ˈˈ oxy)- 3 hydroxy benzoquinone (1), (3β –5α– dihydroxy –6β– phenyl acetyloxy – ergosta –7, 22 – diene) (2) and 2- dodecanol (3). The results of bio-assays revealed that the compound (1) and (2) exhibit significant inhibition of mycobacterium with MIC of 6.25μg/ml and 25μg/ml respectively, which is similar to the standard streptomycin drug. It also exhibit good DPPH scavenging potential of 72.07±1.95 and 71.63±1.40 % respectively. The cytotoxicity was tested against breast cancer cell line MCF-7 and found compound 1 and 2 had cytotoxicity of 52% and 49% respectively at 100μg/mL. Conclusion: The present study indicated that the isolated secondary metabolites from the endophytic fungus C. cupreum could be a potential lead molecule of antimicrobial agents. Key words: Endophytic fungi, Chaetomium cupreum, Secondary metabolites, Antimycobacterial, Antioxidant.