ฤทธิ์ต้านออกซิเดชันของสารสกัดบริสุทธิ์บางส่วน จากเปลือกมังคุด

Abstract

The objective of this study was to screen antioxidant activity of partial purified extracts from mangosteen pericarp. Dried mangosteen pericarps were refluxed in methanol at 60°C for 6 h. Methanol extract was then separated by partitioning between dichloromethane and water. The dichloromethane phase was dried and partial purified fractions were obtained by silica gel column chromatography eluting with dichloromethane-methanol gradient. Thin-layer chromatography was carried out. Antioxidant activity of the fractions were studied using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2-azinobis (3-ethyl-benzothiazoline-6-sulfonic acid) (ABTS) technique. Trolox was used as positive control. Twenty-eight fractions were obtained from the column chromatography. Only six fractions showed a spot of a-mangostin in TLC chromatograms. Concentrations of Trolox required to inhibit DPPH and ABTS radical formation by 50% (IC₅₀) were 258.8±0.47 mM and 182.9±0.54 mM, respectively.  It was found that fractions No.1, 3 and 4 had less antioxidant activity (IC₅₀ value > 1 mg/ml). There was no significant difference between fractions No.2, 5 and 6 in antioxidant activity (IC₅₀ values ranged from 200-300 mg/ml). The three fractions would be considered to be used for preparation of a health product.