低分子质量核桃多肽抗氧化及抗肿瘤活性研究

The Antioxidant and Anti-Tumor Abilities of Low-Molecular-Weight Walnut Peptides

研究了核桃发酵多肽的抗氧化效果及抗肿瘤活性。结果表明，此多肽具有一定的抗氧化及抗肿瘤活性，当样品质量浓度为2mg／mL时其DPPH自由基清除率为91．7％，对人小肠癌细胞（Caco-2）的Ic50值为3．67mg／mL。对4组分发酵多肽（分子质量〉30、10～30、5～10ku及〈5ku）进行抗肿瘤活性的试验及筛选．发现〈5ku组分有较强的抗肿瘤活性，表明低分子质量多肽对Caco-2细胞增殖具有较强的抑制作用（IC50值为2．63mg／mL），且该样品不仅抑制Caco-2细胞生长，对人乳腺癌细胞（MCF-7）增殖也有显著的抑制作用（IC50值为3．76mg／mL），而对非肿瘤细胞大鼠小肠隐窝上皮细胞（IEC一6）未显示显著的抑制作用。以上结果表明，核桃粕发酵产生的小分子活性多肽有明显的抗氧化及抗肿瘤活性。

In the paper, the antioxidant and antineoplastic activity of walnut polypeptide after fermented has been researched. The results showed that the walnut polypeptide had an antioxidant activity and the clearance rate of its DPPH · free radical was 91.7% at 2 mg/mL also with an inhibition on proliferation of human colon cancer （ Caco -2） cells （IC50 value of 3.67 mg/mL）. The walnut polypeptide was separated into four fragments, including A1 （MW 〉30 ku）, Az（MW：10 -30 ku）, A3（MW：5 - 10 ku） and A4（MW： 〈5 ku）, to determine the different inhi- bition on tumor cells. The fragment An exhibited obvious inhibition （IC50value of 2.63 mg/mL）and a certain extent of inhibition on the proliferation of MCF - 7 tumor cells （ IC50 value of 3.76 mg/mL）. However, no significant inhib- itory effect of the fragment A4 was observed on IEC -6 cells. The results indicated that the polypeptide derived from walnut protein cake had antioxidant and antineoplastic activities.