Antioxidant Activities of Baccaurea sp.
Nurul Shafiqah Hashim a, Kheng Leong Ooi a, Ahmad Rosma b & Shaida Fariza Sulaiman a
a School of Biological Sciences, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia.b School of Industrial Technology, Universiti Sains Malaysia, 11800 USM, Pulau Pinang, Malaysia.
Ethyl acetate and methanol extracts of different parts of Baccaurea motleyana (Rambai), Baccaurea polyneura (Jentik) and Baccaurea macrocarpa (Tampoi), as well as their juice and freeze dried juice were then evaluated for their antioxidant activities using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, ferric reducing antioxidant potential (FRAP), and metal chelating assays. For DPPH, FRAP and metal chelating, methanol extracts of B. polyneura’s branches, seeds and peels showed the highest activity with the lowest EC50 values of 16.32±0.39 µg/mL, 4.28±0.02 µg/mL, 101.46±14.04 µg/mL, respectively. The methanol extracts of B. polyneura’s seeds and branches with 92.08±2.80 µg GAE/mg extracts and 97.89±0.60 µg GAE/ mg extracts of total phenolic content were selected for fractionation process by using paper chromatography. All fractions were then tested for their DPPH and FRAP activities. Fraction 1 and fraction 2 of B. polyneura’s seeds, together with fraction 2 of B. polyneura’s branches showed the best activities for both DPPH and FRAP. Their EC50 for DPPH test were 85.64±5.05 µg/mL, 50.10±3.01 µg/mL and 78.48±12.78 µg/mL, while their EC50 for FRAP were 12.01±0.75 µg/mL, 10.96±0.06 µg/mL, 14.76±0.17 µg/mL, respectively. Based on the chemical profiling, the antioxidant activities of these fractions were found to be mainly contributed by quercetin derivatives.
Keywords: Baccaurea motleyana, Baccaurea polyneura and Baccaurea macrocarpa