甘薯活性多糖抗突变作用的体外实验研究

为了探讨甘薯的保健作用，本文利用鼠伤寒沙门氏菌营养缺陷型回复突变试验（Ames试验）对甘薯活性多糖进行了体外抗突变作用的研究。结果表明：甘薯活性多糖具有显著的抗突变作用，当其剂量为20mg/平皿时对2－AF、Ba]p和AFB1的致突变性抑制率均达到70％以上，并且呈明显的剂量－效应关系；甘薯活性多糖的抗突变作用主要是通过阻断致突变物使正常细胞变为突变细胞而实现的，也包括部分去突变作用，但促进突变细胞修复的作用不明显；随着121℃高温处理时间和紫外光（30W，25cm)照射时间的增加，甘薯活性多糖的抗突变作用有所减小，而在pH3．5－pH7．5下处理30min后对其抗突变作用影响不大，超过这个pH范围，抗突变作用都有所减小。

Antimutagenic Activities of Active Polysaccharide Ext ract from Sweet Potato Based on Ames Test

Antimutagenicities in vitro of active polysaccharide is olatedfrom sweet potato were studied by Ames test,probing into health function of sweet potato.The results indicated that sweet potato polysaccharide showed st rong antimutagenic activities with inhibition rates of more than 70% to B〔a〕p, 2-AF and AFB1 at dose of 20mg/plate.The results on mechanism suggested that de smutagenicities and bio-antimutagenicities coexisted,while the latter was the ma in way that sweet potato polysaccharide inhibited mutagens.The antimutagenic eff ects of polysaccharide decreased.When treat the times of 121℃ heating and ultro violet (30W,25cm)treatment were prolonged.The antimutagenic activities of polysa ccharide remained stable at pH3.5 to 7.5 treating for 30min,but decreased at pH out of this range.