Total phenolic content and antioxidant activity of some Malaysian herbs

Herbs have drawn much attention of people worldwide, not only because of their economic value as food products, but also for their antioxidant compounds. Thus, this study was conducted to investigate the total phenolic content and antioxidant activities on three Malaysian herbs by using Soxhlet extraction method. The herbs were Eugenia polyantha (Serai kayu), Euodia redlevi (Tenggek burung) and Limnocharis flava (Sudu itik). The total phenolic content and antioxidant compounds were extracted using distilled water at three different extraction time (4, 8 and 12 hour). The extracts were then evaluated using Folin-Ciocalteu reagent for their total phenolic content and 2, 2-Diphenyl-1-picrylhydrazyl hydrate (DPPH) assay for their antioxidant compounds. Further analyzed was done using High Performance Liquid Chromatography (HPLC) to further verifying the ascorbic acid existence in the extracts. It was found L. flava showed the highest content of total phenolic compounds (15.01 mg gallic acid equivalent (GAE) per 1 g of sample) with the antioxidant capacity standing at 20.42 mg ascorbic acid equivalent (AAE) per 1 g of sample after 8 hour extraction. While, E. polyantha showed the highest value of antioxidant capacity (21.19 mg AAE/g) with total phenolic content of 9.99 mg GAE/g. In HPLC analysis, it was found that E. polyantha and L. flava after 8 hour extraction contained 0.7625 and 0.9745 mg AAE/g of ascorbic acid respectively