Perbandingan Kapasitas Antioksidan Dan Kadar Asam Klorogenat Ekstrak Biji Kopi Robusta (Coffea Canephora) Terfermentasi Kombucha Dan Non Fermentasi

Abstract

Free radicals refer to highly reactive molecular species that may induce cellular damage and contribute to degenerative diseases. Antioxidants play an important role in neutralizing free radicals and preventing oxidative stress. Robusta coffee (Coffea canephora) contains bioactive compounds, particularly chlorogenic acid and caffeine, which contribute to its antioxidant activity. Kombucha fermentation is a processing method that has the potential to modify the bioactive compound profile and alter the functional properties of coffee. This study aimed to compare the antioxidant capacity as well as chlorogenic acid and caffeine contents of kombucha fermented and non fermented robusta coffee beans. Fermentation was carried out using a kombucha starter for 14 days under controlled conditions. The coffee beans were subsequently extracted using ultrasonic-assisted extraction with 96% ethanol. Antioxidant capacity was evaluated using the DPPH method based on IC₅₀ values, while chlorogenic acid and caffeine contents were determined by TLC densitometry. The results demonstrated that kombucha fermentation resulted in a statistically significant difference in antioxidant capacity, indicated by a decrease in IC₅₀ value of 7.755 µg/mL compared to the non-fermented extract. In contrast, no statistically significant differences were observed in chlorogenic acid and caffeine contents, despite numerical decreases of 0.09% and 0.14%, respectively. These findings indicate that kombucha fermentation significantly improves antioxidant capacity based on statistical analysis, while changes in chlorogenic acid and caffeine contents are not statistically significant.