锌离子结合类蛋白反应修饰肽的稳定性研究

Stability of Modified Peptide Using Zinc Binding and Plastein Reaction

以牡蛎为原料制备锌离子结合类蛋白反应修饰肽,重点以锌保留率为指标,研究了p H,胃肠道消化酶,热处理,储存时间等因素对锌离子结合类蛋白反应修饰肽的稳定性的影响,并与锌离子结合多肽和锌离子结合谷氨酸的稳定性进行了比较。结果表明,红外光谱分析发现类蛋白反应后有新的物质生成;锌离子结合物在p H 2.0下都易于解离,在p H 9.0下都比较稳定,且锌离子结合肽类的稳定性明显强于锌离子结合谷氨酸的稳定性(P<0.05);锌离子结合物对消化酶都具有一定的抗消化性,且锌离子结合肽类的稳定性明显强于锌离子结合谷氨酸的稳定性(P<0.05);锌离子结合类蛋白反应修饰肽和锌离子结合多肽对热处理较为敏感,其稳定性明显低于锌离子结合谷氨酸的稳定性(P<0.05);随着储存时间的延长,锌离子结合物都保持较高的稳定性,锌保留率可达95.50%左右。

Modified peptide was prepared from oysters by zinc binding and plastein reaction. The effects of p H, digestive enzymes, heat treatment, storage time, and other factors on the stability of the modified peptide were studied. Additionally, the stability of the new modified peptide was compared with that of zinc-binding polypeptide and zinc-binding glutamic acid. Fourier transform infrared(FT-IR) spectroscopy indicated that new substances were generated after plastein reactions; zinc-binding complexes were easily degraded at p H = 2.0, while they were relatively stable at p H = 9.0; and the stability of zinc-binding glutamic acid was significantly lower than that of zinc-binding peptides(p < 0.05). All zinc-binding complexes exhibited resistance to digestive enzymes and the stability of zinc-binding glutamic acid was significantly lower than that of other zinc-binding peptides(P < 0.05). The modified peptide and zinc-binding polypeptides were sensitive to heat treatment and their stability was significantly lower than that of zinc-binding glutamic acid(p < 0.05). Zinc-binding complexes exhibited good stability and zinc retention rate reached up to 95.50% as storage time increased.