The Effect of Processing Variables on Antioxidative Capacity of Mangosteen Peel （Garcinia mangostana L.） Extract

Mangosteen peel （Garcinia mangostana L.） is well known as an excellent source of antioxidative compounds. The objective of this study was to determine the most suitable processing condition for ethanolic extraction of mangosteen peel. The experimental factors included raw material prepared as fresh and dried forms, material-to-solvent ratio varying at 1：3, 1：4, 1：5, 1：6, 1：9 and 1：12, and contacting time at 1, 3, 6, 9, 12 and 16 hours. Antioxidative capacity of all extracts were evaluated and compared according to DPPH radical scarvenging assay, trolox equivalent antioxidant capacity （TEAC assay） and total phenolic compounds. It was found that the extract from dried mangosteen peel had significantly stronger antioxidative capacity than that from fresh mangosteen peel （P 〈 0.05）. The suitable ethanolic extraction was found at the material-to-solvent ratio of 1：6 and 12 hours of contacting time. Mangosteen peel extracts prepared from fresh peel, dried peel, boiled and dried peel were also tested for oxidative r