Antioxidant activity of endophytic bacteria origin from endocarp of cocoa pod husk

Abstract

Cocoa (Theobroma cacao L.) is one of the leading commodities in Indonesia. Cocoa pod husk is part of the mesocarp or part of the cacao pod husk that wraps the cocoa beans. Endophytic bacteria are microbes that live in host plant tissues and do not interfere with host plant growth. This study aimed to determine characteristics of endophytic bacterial isolates contained in endocarp cocoa pod husk and to determine the antioxidant power of endophytic bacterial isolates contained in cocoa pod husk. Isolation of endophytic bacteria from the inner pod of cocoa which be expected to produce antioxidants has been carried out. Isolation of bacteria using surface sterilization method. Antioxidant test using DPPH method (1,1-diphenyl-2-picrylhydrazyl) with UV-Vis spectrophotometer at 600 nm. Two isolates out of four endophytic bacteria were obtained from the results of the preliminary test of phenolic tests, namely isolates of bacteria KK2 and KK3 which had different colony morphology. The results of the secondary metabolite test showed that the bacterial isolates KK2 and KK3 contained flavonoids and phenolics. Based on the test results, the value of IC₅₀ of bacterial isolate KK2 was 2104.58 ppm and KK3 bacterial isolate was 1123.04 ppm. The highest antioxidant activity was possessed by bacterial isolate KK3 and was classified as a very weak antioxidant.