Bioactive compounds content and antioxidant activity of Phyllanthus emblica fruit extracts from different varieties cultivated in Thailand

Abstract

The fruit of Phyllanthus emblica L. have been used for expectorant, laxative and antiscobutic [1]. This fruit is also an important component in Thai traditional medicines, dietary supplements and cosmetics. In Thailand, there are many varieties of P. emblica. The purpose of this research was to analyze and compare the amounts of bioactive compounds and antioxidant activity of the extracts of P. emblica from different varieties in Thailand. Five varieties of P. emblica fruit, including Pan Siam, Thong Siam, Petch Siam, Tavai and Mae Look Dok, were collected and separately macerated with 95% ethanol. The content of total phenolic compounds, total tannins and total flavonoids of each extract was evaluated using Folin-Ciocalteu procedure, protein precipitation method and aluminium chloride colorimetric method, respectively [2]. Moreover, the antioxidant activity of the extract were performed using DPPH and FRAP assays [2 – 3]. The results showed that Tavai contained the highest amount of total phenolic compounds (25.71 ± 1.69 mg gallic acid equivalent per 100 mg extract) and total tannin (20.92 ± 1.39 mg of tannic acid per 100 mg extract), while Pan Siam give the highest amount of flavonoid compounds (4.66 ± 0.15 mg of quercetin per 100 mg extract). For antioxidant activity, the extract of Tavai also promote a good antioxidant activity (DPPH assay: EC50= 3.87 ± 0.11 µg/mL and FRAP assay: FRAP value = 49.76 ± 2.40µmol of FeSO4 per 100 mg extract). This information can be used to select the appropriate variety of P. emblica fruit for pharmaceutical production in Thailand.