柠檬酸提取海带渣中多糖及其抗氧化活性与结构的研究

以海带渣为原料,采用柠檬酸提取法提取海带渣中多糖,并与直接柠檬酸提取的海带多糖进行抗氧化活性与结构比较。研究表明,海带渣多糖的提取率为7.00%±0.03%,其抗氧化活性与直接酸提的海带多糖相当,具有较好的氧自由基清除能力(ORAC值为130.13μmol Trolox/g)、DPPH自由基清除能力(18.89μmol Trolox/g)、ABTS自由基清除能力(53.58μmol Trolox/g)和还原力(37.56μmol Trolox/g),其中ORAC值比抗氧剂BHT高2倍。所得海带渣多糖的主要组分分子量为310182u(2.73%)和30515u(97.27%)。红外光谱图分析表明海带渣多糖与直接酸提的海带多糖结构相似。 

The extraction of polysaccharide from Laminaria japonica residue by citric acid and study on antioxidant activities and structural characteristics

Laminaria japonica residue was used as the material to obtain polysaccharide by the citric acid extraction, and the antioxidant activities and structural characteristics of the polysaccharide had been compared with those of polysaccharide obtained by direct citric acid extraction. The results showed that the yield of the polysaccharide was 7. 00%±0. 03%, and the antioxidant activities were similar with those of polysaccharide obtained by direct citric acid extraction, with the values of oxygen radical absorbance capacity, DPPH radical scavenging activity, ABTS radical scavenging activity and reducing power of 130. 13μmol Trolox/g, 18. 89μmol Trolox/g, 53. 58μmol Trolox/g and 37. 56μmol Trolox/g, respectively. Moreover, the value of ORAC was 2 times higher than that of BHT. Gel permeation chromatography analysis indicated that the polysaccharide comprised two components, the molecular weights were 310182u (2. 73%) and 30515u (97. 27%) separately. The infrared (IR) spectra analysis demonstrated that the polysaccharide had resemblant structure with that obtained by direct citric acid extraction.