GC-MS composition of leaf extract of Piper cf. arcuatum blume and their antioxidant activity and toxicity studies

Abstract

In order to study the chemical characteristic and bioactivity of red betel (Piper cf. arcuatum Blume) leaf extracts, a simple and reliable GC-MS method was developed to identify the chemical components from the extract, followed by antioxidant activity assay using DPPH (1,1-Diphenyl-2-picrylhydrazyl) method and toxicity studiy using Brine Shrimp Lethality Test (BSLT) study. Purification step was carried by column chromatography, containing silica gel as stationary phase, and mixture of n-hexane, ethyl acetate and methanol as mobile phase. The DPPH assay showed that methanolic extract has the highest antioxidant activity, compared to n-hexane and ethyl acetate extract, and fraction B has the highest antioxidant activity, compared to fraction A and C. GC-MS analysis of fraction B revealed that the fraction was mainly composed of 6,7-dimethoxy-2,2-dimethyl-1-benzopyran. Fragmentation and the most probable biosynthetic route were also proposed in this study. Brine Shrimp Lethality Test (BSLT) study showed that methanolic extract has the highest toxicity with LC50 value of 16.15 ppm. The main compound in this extract was a derivative of benzopyran, which has high antioxidant capacity and self-defence capability against predator. The results demonstrated that GC-MS method was proven to be an excellent tool to identify chemical constituens in the red betel (Piper cf. arcuatum Blume) leaf extract.