Optimization of total phenolic extraction of Chromolaena odorata leaf for antifungal activity against plant pathogens

Phenolic compounds are secondary metabolites mainly responsible for different pharmacological activities of the plant extracts. In this study, microwave-assisted extraction (MAE) variables were optimized for the extraction of the phenolic compounds from Chromolaena odorata (C. odorata) by using a central composite design (CCD) of response surface methodology (RSM). The optimized conditions were at 62oC for 3 min with solvent to feed ratio of 14:1 (mL/g) and ethanol concentration of 50% (v/v). The highest yield of total phenolic compounds was 75.76 mgGAE/g. Ethanol extract clearly showed antifungal activity through antifungal index. The antifungal effect Phytophthora capsici, Fusarium oxysporum and Colletotrichum siamese were 79.07%, 78.66% and 78.42%, in 0.5% of ethanol extract, respectively