GC-MS profile, total phenolic, and DPPH radical scavenging activity of Saurauia minahassae stembark ethyl acetate extract

Abstract

Several species of the genus Saurauia have been traditionally used as remedies. However, Saurauria minahassae, as an endemic plant, is still understudied. This study aims to reveal the total phenolics, GC-MS profile, and bioactivity as DPPH free radical scavengers of ethyl acetate extract of S.minahassae collected from Banggai Island, Indonesia. Determination of Total Phenolic Content (TPC) was conducted using the colorimetry method by spectrophotometer. Thin layer chromatography (TLC) and TLC-bioautography performed analysis of secondary metabolites and qualitative DPPH free radical scavenging activity, respectively. GC-MS analysis was conducted to identify the chemical compounds of the extract. The extract’s IC50 value and Antioxidant activity index (AAI) were performed by serial microdilution method on the 96-microwell plate. The results showed that TPC was 432.33 mg GAE/g extract. TLC analysis revealed several metabolites, and TLC-bioautography also revealed several compounds active as DPPH free radical scavengers. The ethyl acetate extract of S. minahassae is categorized as a very strong DPPH free radical scavenger or potent antioxidant with an IC50 value of 3.29 ug/ml and AAI of 9.32. GC-MS profile of the ethyl acetate extract of S.minahassae stembark contained several compounds with antioxidant activity. The potential antioxidant activity of S. minahassae stembark extract was contributed by phenolic content and several compounds with antioxidant activity in the extract. This extract could be a good source of natural antioxidants, and S. minahassae sustainability as an endemic plant should be maintained.