TLC profiling and antioxidant activity of phenolic compound from Sterculia oblongata bark extract

Abstract

Abstract. Murningsih T, Praptiwi, Liana, Fathoni A. 2019. TLC profiling and antioxidant activity of phenolic compound from Sterculia oblongata bark extract. Nusantara Bioscience 11: 44-48. In the present study, we investigated the total phenolic content and in- vitro antioxidant activity of Sterculia oblongata. Total phenolic content (TPC) of the methanol extract was examined by Folin-Ciocalteu reagent and gallic acid as standard. The in-vitro antioxidant activity was performed by DPPH free radical scavenging activity and ?-carotene bleaching assay. The result showed that the TPC of methanol extract was the highest (P<0.05) compared to other extracts. There is a positive and significantly very high Pearson’s correlation between antioxidant activity index (AAI) and TPC (r = 0.996). A negative and significantly high Pearson’s correlation was obtained between IC₅₀ value and TPC (r = -0.885). The result of ?-carotene bleaching assay showed that the rate of the decreased antioxidant activity of S.oblongata extract was lower than that of ?-carotene/linoleic acid. The results suggest that the extract of S. oblongata can be used as a natural antioxidant. However, further investigation to isolate and identify the chemical compounds responsible for antioxidant was needed