陕北野生枸杞多糖的体外抗氧化活性

目的：测定陕北野生枸杞中总糖含量、糖醛酸含量以及体外抗氧化活性。方法：采用苯酚- 硫酸法，测定枸杞提取物的总糖含量；用硫酸- 咔唑法，测定枸杞多糖的糖醛酸含量；通过红外光谱技术初步分析枸杞多糖基团的构成；并以VC 为对照，比较枸杞多糖对二苯代苦味酰基(DPPH)自由基、超氧阴离子自由基、羟自由基的 体外抗氧化活性及还原力。结果：陕北枸杞提取物中的总糖含量为58.31%，糖醛酸含量为32.17%。 当枸杞多糖的质量浓度为1mg/mL 时，对DPPH 自由基、超氧阴离子自由基、羟自由基清除率分别为81.30%、50.33% 和60.57%，还原能力比VC 稍低。结论：陕北野生枸杞多糖有很强的抗氧化活性。

in vitro Antioxidant Activities of Polysaccharides from Wild Lycium barbarum in North Shaanxi

Objective: To determine the content of total polysaccharides (LBP) and uronic acid from wild Lycium barbarum, as well as their in vitro antioxidant activities. Methods: phenol-sulfuric acid and sulfuric acid-carbazole method were used to evaluate the total contents of LBP and uronic acid, respectively. LBP structural composition was detected by IR spectra. DPPH, superoxide anion radicals, hydroxyl radical scavenging and reducing power of LBP were analyzed for antioxidant activity in vitro, with VC as control. Results: The polysaccharides and uronic acid content was 58.31% and 32.17%, respectively, in the extract of wild plants. At 1 mg/mL of polysaccharide, the DPPH, superoxide radical and hydroxyl radicals-scavenging activities was 81.30%, 50.33% and 60.57%, respectively, while the reducing power was slightly lower than that of VC. These results suggested that polysaccharides in extract from wild plants show potent antioxidant activities, which might provide a scientific basis for further exploitation and the significance of protecting Lycium barbarum in north Shaanxi province.