Background and objective: The content of polyphenols in cacao beans can be modified during the processing of cacao. This study aimed to obtain the fraction of cacao bean extract polyphenols with the highest antioxidant activity and bioactive compounds profile of extracts and their fractions on cacao beans.
Materials and methods: The cacao beans (fermented for 5 days and unfermented) were blanched (5 min; 95°C), followed with defatted, freeze-dried and extracted uses 80% ethanol solvent. The extract obtained was then fractionated using n-hexane, chloroform, ethyl acetate, n-butanol and aqueous. Extracts and fractions obtained are calculated for yield, total polyphenol uses Folin-ciocalteu reagent, total flavonoid uses AlCl3, antioxidant activity uses DPPH and FRAP methods, functional group uses fourier transform infrared spectroscopy (FTIR) and polyphenol compound profiles uses UHPLC-MS/MS.
Results: The results showed that the aqueous fraction had the highest yield but lowest chemical content and antioxidant activity. The unfermented cacao beans extract undergoing fractionation using ethyl acetate showed polyphenol content, flavonoids, DPPH free radical scavenging activity and highest ferric reducing activity. The FTIR analysis showed that the cacao bean extract and its fractions had O-H, C-H, C=O, C=C and C-O-C functional groups. Cacao beans extracts and ethyl acetate fractions were dominated by procyanidin compounds, especially dimer B2. Cacao bean fermentation caused a decrease in procyanidin compounds (monomer to nonamer) and alkaloids (theobromine and caffeine).
Conclusion: Unfermented cacao bean extraction is then followed by fractionation with ethyl acetate solvent, obtained the fraction with highest chemical and antioxidant activity.
Keywords: Cacao beans; UHPLC-MS/MS; antioxidant activity; ethyl acetate solvent; polyphenol; procyanidin compounds; unfermented.