PERBANDINGAN AKTIVITAS ANTIOKSIDAN EKSTRAK ETANOL BIJI KOPI ARABIKA (Coffea arabica L.) DAN KOPI ROBUSTA (Coffea canephora L.) SEMENDE DARAT LAUT SUMATERA SELATAN

Abstract

This research was conducted to determine and compare the antioxidant capacity of 70% ethanolic extracts of Arabica (Coffea arabica L.) and Robusta (Coffea canephora L.) coffee beans collected from Semende Darat Laut, South Sumatra, Indonesia. The coffee beans were extracted by maceration using 70% ethanol, while free-radical scavenging activity was examined by the DPPH (1,1-diphenyl-2-picrylhydrazyl) assay and read at 517 nm using UV-Vis spectrophotometry. The Arabica bean extract produced an IC₅₀ of 38.879 µg/mL and was classified as having very strong antioxidant activity. In comparison, the Robusta extract yielded an IC₅₀ of 52.402 µg/mL, which falls into the strong category. As the positive control, vitamin C showed an IC₅₀ of 29.636 µg/mL. Qualitative phytochemical tests detected phenolic compounds, saponins, and steroids in both extracts. These results suggest that Arabica coffee beans from Semende Darat Laut exhibit stronger antioxidant potential than Robusta beans, presumably due to differences in phenolic constituents, including chlorogenic acid. Thus, both local coffee varieties may be considered prospective natural antioxidant sources for health-related product development.