Optimization and characterization of n-hexane extracts of arabica coffee ground (Coffea arabica L.) fromgayo plateau as source of natural antioxidant

Abstract

Arabica coffee is a major commodity crop in the Gayo Plateau, Aceh Province. Utilization of coffee in the area only as a raw material for making coffee drinks and produce waste that is not utilized. The aim of this study is optimization and characterization of n-hexane extract of Arabica Gayo coffee ground (Coffeaarabica L.) as a source of natural antioxidant. The extraction process used soxhlet method with n-hexane solvent. Characterization of arabica coffee ground oil consist ofanalysis of functional group using FTIR, component analysis using GC-MS and antioxidant analysis using DPPH method. The optimum time of the soxhletprocess of Arabica coffee is 180 minutes with rendement of 9,54%, analysis of functional group shows CH2 asymmetric stretch at 2922 cm−1, CH2 symmetric stretch at 2853 cm−1, C=O asymmetric stretch at 1741 cm−1, CH2 bending at 1458 cm−1, C-CH3 vibration at 1159 cm−1 and CH vibration at 718 cm−1. The main component of Arabica Gayo coffee ground oil is 1,2-benzenedicarboxylic acid, bis(2-ethylhexyl) ester with an area of 18.09%, antioxidant activitiy of Arabica Gayo coffee ground oil is very weak with IC50 value = 1222,31 ppm.