Total Phenolics, Flavonoids, and Anthocyanin Contents of Six Vireya Rhododendron from Indonesia and Evaluation of their Antioxidant ActivitiesMohamad Rafi, Salina Febriany, Puji Wulandari, Irma Herawati Suparto, Taopik Ridwan, Sri Rahayu, Dyan Meiningsasi Siswoyo.
Six species of Vireya Rhododendron from Indonesia i.e. Rhododendron javanicum, R. jasminiflorum, R. konori, R. malayanum, R. retusumandR. seranicum were analysed for total phenols, flavonoids, anthocyanin and antioxidant activity for its ethanolic extract from leaves and twigs. Total phenols, flavonoids and anthocyanin were varied between 11.98-48.11 mg equivalent gallic acid/g dried powder, 0.78-8.92 mg equivalent quercetin/g dried powder and 0.12-0.29 mg equivalent cyanidin-3-glucoside/g dried powder, respectively. Antioxidant activity was investigated by using 2,2-diphenyl-1-picrylhidrazyl (DPPH), ferric reducing antioxidant power (FRAP), and cupric ion reducing antioxidant capacity (CUPRAC). R. retusum twig bark extract has the highest antioxidants capacity using DPPH method about 36.68 µmol trolox/g dry weight. R. konori leaves has the highest antioxidant capacity about 941.76 and 1793.62 µmoltrolox/g dried powder by FRAP and CUPRAC method, respectively. From the result obtained, only total phenols content correlated with the antioxidant measured by DPPH, FRAP and CUPRAC. So the antioxidant activity not only attributed from the flavonoids and anthocyanin but from other phenols compounds.
antioxidant activity, Rhododendron, anthocyanin, flavonoids, phenols