Quantitative analysis of secondary metabolites produced by Chaetomium globosum Krunze ex Fr.

Abstract

Chaetomium globosum Krunze ex Fr. (Cg) has been identified as a potential antagonist of Bipolaris sorokiniana and Ascochyta rabei . This biocontrol agent has been found to be producing antifungal metabolites. Six different isolates of Cg were characterized for the production of antifungal metabolites. The quantitative estimation of crude extracts showed maximum production by isolate Cg3 (47.2μg/mg mycelium) followed by Cg2 (44.2μg/mg). Isolate Cgl produced minimum quantity of metabolites (7.44μg/mg). Crude extracts of secondary metabolites from all the isolates of C. globosum when resolved by thin layer chromatography showed that the isolate of Cgl produced only two compounds of R r value 0.17 and 0.48, while isolate Cg2 produced thirteen compounds, followed by 11 compounds produced by isolate Cg3, The metabolite from spore germination fluid of isolate Cg2, when resolved on TLC plate along with crude extracts from culture filtrate of Cg2, showed production of about same number of compounds. One of the purified compounds from isolate Cg2 when used for bioassay against Bipolaris sorokiniana, Rhizoctonia solani, Fusarium udum and Macrophomina phaseolina pathogens proved effective in inhibiting the growth up to 70 percent.