Effects of Drying Methods on the Proximate Composition and Antiproliferative and Antioxidant Properties of Extracts from the Sea Cucumber Stichopus japonicus

摘要

The study determined the effects of drying methods and various extracts/fractionation solvents on the proximate composition, cytotoxic activity and antioxidant property of sea cucumber (Stichopus japonicas Selenka, 1867). The two drying techniques employed were freeze drying (FD) and low temperature vacuum drying (LTVD). Dried and raw samples were extracted with acetone/methylene chloride (A+M) and methanol (MeOH) and the extracts were fractionated using n-hexane, 85% aq. methanol (MeOH), butanol (BuOH) and water. The extracts/fractions were concentrated to dryness and subsequently used in the various assays at concentrations of 0.1, 0.5, and 1.0 mg mL(-1). Cytotoxic activity against AGS human gastric and HT-29 human colon cancer cell lines was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, while antioxidant activity was measured using fluorescence sensitive dye 2'-7' dichlorofluorescein-diacetate (DCFH-DA).