ANTIOXIDANT ACTIVITIES OF GREEN BEAN AND ROASTED BEAN ARABICA COFFEE FROM GAYO, JURIA, AND WAMENA USING DPPH AND FRAP METHODS

• Main Author: Salam Juarna, Kartika
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/45816
• Institution: Institut Teknologi Bandung

Background and purpose: Free radicals are one of the risk factors for degenerative diseases in human body. Excessive free radicals exposure makes the body need an exogenous antioxidants that can be obtained through food or drink. Coffee has antioxidant activity. The objectives of the study were to determine the antioxidant activity of Arabica green coffee and roasted coffee by DPPH and FRAP methods, determine total phenol and flavonoid, analyze the correlation of total phenol and flavonoid with IC50 DPPH and EC50 FRAP, and also correlation between IC50 DPPH and EC50 FRAP. Methods: Extraction was carried out by reflux using three solvents with increasing polarity, namely n- hexane, ethyl acetate and ethanol. Determination of IC50 DPPH and EC50 FRAP capacity, total phenolic and flavonoid content were done by uv - visible spectrophotometric method. Correlation of total phenolic and flavonoid with IC50 DPPH and EC50 FRAP, and correlation between IC50 DPPH and EC50 FRAP were analyzed by Pearson’s method. Results: Ethanolic extract of GGB (Gayo Green bean) showed the highest antioxidant activity by DPPH method with IC50 1.35 ?g/mL, while by FRAP method was shown by WGB ethanol extract (Wamena Green bean). IC50 DPPH and EC50 FRAP show a positive and significant correlation on all extracts except the Juria Green bean extract. IC50 DPPH and EC50 FRAP gave positive and significant correlation in Gayo green bean (GGB), Gayo roasted bean (GRB), Wamena green bean (WGB), Wamena roasted bean (WRB), and Juria roasted bean (JRB) extracts. Ethanolic extracts of green bean and roasted bean from Gayo, Juria and Wamena are very powerful antioxidants. Flavonoid compounds are the main contributors to the antioxidant activity of GGB, GRB, JRB, WGB, WRB extracts. The DPPH and FRAP methods provide a linear result on the antioxidant activity of GGB, GRB, JRB, WGB, WRB extracts.