'Penerbit Universiti Kebangsaan Malaysia (UKM Press)'
Abstract
This research was conducted to determine the monosaccharide profile and antioxidant activities of the sulphated
polysaccharide fucoidan, extracted from Sargassum sp. harvested in Batam, Indonesia. Crude fucoidan (Fsar) was
extracted using low pH (pH 2) acid method, obtaining a yield of 5.5% (w/w), and the chemical properties of Fsar were
subsequently compared to commercial fucoidan (Fcomm), obtained from Japan. Sulphate contents were determined
using spectrophotometric analysis, where Fsar (5.21±0.35%) and Fcomm (8.80±0.19%) differed significantly (p<0.05).
Monosaccharide profiling was performed using methanolysis and gas chromatography-flame ionisation detector
(GC-FID). Fsar contained fucose (138.34 µg/g), 4-O-methyl-glucuronic acid (105.39 µg/g), galactose (70.49 µg/g)
and glucuronic acid (30.60 µg/g) while Fcomm contained fucose (520 µg/g) and glucuronic acid (62.93 µg/g) as its
main composition. Antioxidant activities were analysed through 2,2-diphenyl-1-picrylhydrazyl (DPPH), superoxide
anion (SOA) and hydroxyl radical (·OH) scavenging activities. DPPH scavenging activity of Fsar (40.67±4.0%) was
significantly higher (p<0.05) than Fcomm (10.11±1.0%), while SOA and ·OH scavenging activities showed no significant
difference (p>0.05) between Fsar and Fcomm. Fsar showed significant differences (p<0.05) in chemical properties and DPPH
scavenging activities compared to that of Fcomm. Fucoidan from Southeast Asia waters has the potential for application
as functional ingredients