Metabolite Profiles and Antioxidant Activity of Garut Arabica Green Coffee Beans

The metabolite profiles of Arabica green coffee beans from four Garut regions (Cikuray, Kamojang, Patrol, and Papandayan) were evaluated by ¹H NMR-based metabolomics. The antioxidant activity of the green coffee beans was examined with the DPPH and FRAP test methods. The OPLSDA model successfully categorized the green coffee beans based on their regional origin. The S-plot generated by the two-class OPLSDA model successfully showed the typical metabolites of green coffee beans from each region. Citric acid was found as a discriminant metabolite of Kamojang coffee beans. Whereas Patrol coffee was characterized with sucrose and 5-CQA. Asparagine and trigonelline were the distinguishing metabolites of Papandayan coffee. Meanwhile, Cikuray coffee was characterized by GABA and caffeine when compared to the coffee samples of Kamojang and Patrol. The assay results indicated that all Garut coffees had strong antioxidant activity, with Patrol coffee being the most potent sample. The IC₅₀ and EC₅₀ values resulted from DPPH and FRAP tests for Patrol coffee beans were 44.25 ± 0.77 µg/mL and 27.01 ± 0.44 µg/mL, respectively. These results suggested that Garut Arabica green coffee beans (especially Patrol coffee) could be employed as a functional food or beverage ingredient supplying the need for antioxidants. To the best of our knowledge, this is the first report concerning metabolomics of Garut Arabica coffees, one of the interesting coffees from Indonesia.