IDENTIFIKASI SENYAWA DALAM FRAKSI AKTIF EKSTRAK RUMPUT LAUT COKLAT Sargassum hystrix SEBAGAI INHIBITOR ENZIM -GLUKOSIDASE; IDENTIFICATION OF COMPOUNDS IN THE ACTIVE FRACTIONS OF BROWN SEAWEED Sargassum hystrix EXTRACT AS -GLUCOSIDASE ENZYME INHIBITOR

LIS FITRAMADAN, Respati Tri Swasono

2013 | Disertasi | PROGRAM STUDI S2 ILMU KIMIA

This research aims to identify the compounds of the active fractions from the brown seaweed Sargassum hystrix extract as -glucosidase enzyme inhibitor. The study includes sampling, identification of the seaweed, extraction, separation by column chromatography, identification by Liquid Chromatography-Electrospray Ionization Mass Spectrometry (LC-ESIMS) and activity test. The weight of fractions I, II and III are 0.03%, 0.05%, and 0.03%, respectively. Identification by ESI-MS fractions I and II showed the precent of loliolide. Fraction I also contained halogenated furanone, whereas fraction III 4,4’-dihydroxybiphenyl compound. The activity test of each fractions carried out in vitro using -glucosidase enzyme and the substrate of p-nitrophenyl- -D-glucopiranoside. The product of reaction was measured its absorbance using the Elisa microplate reader at 405 nm. At the concentration of 40 ?g/mL, fraksi I, II and III inhibits the -glucosidase enzyme activity by 89.8%, 95.0%, and 96.1%, respectively. IC50 values of fractions I, II and III, were 8.9, 6.3, and 7.6 ?g/mL, respectively. While IC50 value of an antidiabetic drugs of akarbose was only 2.1 mg/mL. Statistical tests-one way ANOVA with 95% confidence level was carried out to distinguish between the IC50 values of each fraction and fraction against of acarbose, with the results differ significantly (P < 0.05).

Kata Kunci : Sargassum hystrix; Metabolit Sekunder; Inhibitor -glukosidase