pH调节法提取牡蛎蛋白及氨基酸、蛋白组成分析

Extraction of Oyster Protein by Alkali Solution Acid Precipitation and Its Amino Acid and Protein Composition Analysis

以牡蛎全脏器为原料,采用pH调节法（pH-shifting）分离提取牡蛎分离蛋白并对其氨基酸组成及蛋白组成进行分析。试验结果表明,牡蛎分离蛋白提取最佳碱溶条件为pH 12~13,最佳酸沉条件为pH 4.5~5.1。在最佳提取条件下获得的牡蛎分离蛋白得率为66.7%,蛋白纯度达92.5%（干基计）。牡蛎分离蛋白各种必需氨基酸均高于FAO/WHO推荐值,约占总氨基酸的42.44%,风味氨基酸和支链氨基酸含量也较高。SDS-PAGE电泳图谱显示牡蛎分离蛋白在200,97,44 ku处均出现比较明显的蛋白条带。本研究结果将为进一步开发利用牡蛎蛋白资源提供理论依据。

This paper studied on the protein isolate extracted from the oyster meat by pH-shifting method,the amino acid and protein composition were investigated. The results showed： the best extracted alkali-soluble and acid precipitation conditions of the oyster protein isolate were pH 12-13 and pH 4.5-5.1, respectively. And the yield of the oyster protein isolate was 66.7%; the purity of protein was 92.5%（dry basis）. A variety of essential amino acids of the oyster protein isolate were higher than the FAO/WHO recommended value, representing approximately 42.44% of the total amino acid, and the flavor amino acids and branched chain amino acid content were also higher. SDS-PAGE pattern showed the oyster protein isolate contained three main bands 200,97,44 ku with higher proportion. These results will provide a theoretical basis data for the further development and utilization of the oyster protein resources.