ANTIFUNGAL ACTIVITY PROFILE OF PIPER LONGUM FRUIT EXTRACT AGAINST PLANT PATHOGENIC FUNGI

Abstract

A series of five-step experiments was conducted to construct the antifungal activity profile of P. longum extracts against plant pathogenic fungi in vitro. The ethanol crude extract exhibited potent activity against all tested fungi using disc diffusion method. The crude extract was then partially fractionated in order by column chromatography using six organic solvents, and evaluated for their antifungal activity. The results revealed that the fractions eluted with diethyl ether (DE) and ethyl acetate (EtOAc) exhibited potent antifungal activity against tested plant pathogens including Colletotrichum capsici, C. gloeosporioides and Fusarium oxysporum f.sp. cubense. This crude extract was also further fractionated with fifty-one mixed solvents with a gradient system, which were also evaluated for their antifungal activity. The fractions obtained from eluting with the combination of DE: EtOAc and petroleum ether (PE): chloroform (CHCl3) showed zone of inhibition towards tested plant pathogenic fungi ranged from 0.65 to 2.00 mm. The results suggested that the active compounds contained in DE and EtOAc fractions as well as micro-fractions from eluting with the mixture of PE: CHCl3 (F5- F8) and DE: EtOAc (F22-F30). The TLC chromatograms and antifungal activity of the macro- and micro-fractions were analyzed for construction the antifungal activity profile of P. longum.