Inhibitory activity of Sargassum hystrix extract and its chloroform fractions on inhibiting the α-glucosidase activity

Seaweed is one of the marine biotas that has several benefits for health and cosmetics. The objective of this study was to isolate and test the activity of chloroform fraction of Sargassum hystrix seaweed extract in inhibiting the α-glucosidase and identification of the active fraction compounds. S. hystrix was extracted by maceration, then partitioned using chloroform and methanol. The chloroform fraction was further separated by column chromatography to obtain purer compounds. The extract of S. hystrix, chloroform fraction resulting from partitioning and chloroform fractions from column chromatography were tested for inhibitory activity against the α-glucosidase. The active chloroform fraction inhibits the α-glucosidase then identified its compounds using Gas Chromatography-Mass Spectrophotometry (GC-MS). The result showed that chloroform fraction (IC50 = 0.726 mg/mL) had a higher inhibitory activity of the α-glucosidase than acarbose (IC50 = 1.890 mg/mL). Column chromatography separation produced seven chloroform fractions. The highest inhibition activity was found in the second chloroform fraction (41.62), third (51.39), and fourth (30.49). Based on GC-MS analysis, several compounds were thought to be able to inhibit the α-glucosidase. The identified compounds were 2-Hexadecene-1-ol, 3,7,11,15-tetramethyl-; Hexadecanoic acid, methyl ester; 9-Octadecenoic acid, methyl ester; Phytol; Stigmasta-5,24(28)-dien-3-ol, (3.beta,24Z)- and 6-Hydroxy-4,4,7a-trimethyl-5,6,7,7a-tetrahydro benzofuran-2 (4H )-one.