ĐÁNH GIÁ HOẠT TÍNH KHÁNG OXY HOÁ VÀ KHẢ NĂNG THAY THẾ PHỤ GIA KHÁNG OXY HOÁ TRONG THỰC PHẨM CỦA CAO CHIẾT MỘT SỐ LOẠI RONG NÂU

Tóm tắt

The study was conducted on four species of seaweeds, Sargassum feldmannii collected from Khanh
Hoa province and Sargassum gracile, Sargassum mcclurei, Sargassum polycystum collected from Ninh
Thuan province. Seaweeds were extracted in two different solvents which were water and ethanol. The
extracts obtained from water extraction at temperature of 50°C ranged from 10.68%-18.98% and
ethanol extraction at temperature of 40-50°C was 13.48%-17.86%. The total polyphenol content of
water extraction was lower than ethanol extraction, the highest in S. gracile (90.01 ± 1.01 mg/g). The
free radical scavenging activity of water extraction was lower than ethanol extraction, the highest in S.
gracile (71.23 ± 0.39%) and lowest in S. feldmannii (38.11 ± 0.12%). Comparing the antioxidant
capacity of the extracts with synthetic antioxidant additives: BHA, BHT, ascorbic acid and tocopherol,
the strongest resistance rate was 151.39% with BHT in S. gracile, All of water or ethanol extractions of
S. feldmannii, S. mcclurei and S. polycystum had resistance rate in the range of 40-90%.
Keywords: antioxidant activity, brown seaweed, Sargassum, total polyphenol content