酶水解猪血红蛋白过程蛋白质降解和氨基酸释放

Protein degradation and amino acid release in the processing of hydrolysis of porcine hemoglobin concentrate

采用商业酶(Pancreatin,Protamex,Pancreatin/Protamex)水解肉品加工业的副产品猪血血红蛋白。水解后的血红蛋白产物采用凝胶过滤色谱(GPC)及HPLC分析水解过程蛋白质降解及氨基酸释放规律。Protamex水解产物具有宽泛的分子量分布且含有大量的大分子肽(>15kDa);Pancreatin水解产物同样具有宽泛的分子量分布,但含有大量的小分子肽(<5kDa)。氨基酸组成分析结果表明,Pancreatin酶和Protamex酶均对疏水性氨基酸有较强的作用能力,而且这两种酶的作用位点有互补效应。Pancreatin/Protamex水解产物具有最为复杂的分子量分布图谱,在酶解24h后,水解得到最高的蛋白质回收率为92·34%。在Pancreatin/Protamex水解后期,产物中的肽尤其是大分子肽(>15kDa)和含有较多疏水性氨基酸的肽容易聚集沉降,导致蛋白质回收率的降低。

Porcine blood hemoglobin, a by- product from meat process industry, was hydrolyzed by using commercial enzymes （Pancreatin, Protamex and Pancreatin/Protamex ）.After the enzymic procedure the hydrolysates were determined by gel filtration chromatography and HPLC to characterize for protein degradation, amino acid release.Protamex hydrolysates had broad molecular mass distribution and highest proportion big peptides（ 〉 15kDa） ;Pancreatin hydrolysates had broad molecular mass distribution and high proportion small peptides（ 〈5kDa）.Amino acid composition analysis demonstrated that two enzymes had specificity for terminal a variety of hydrophobic amino acids and that terminal domain of Protamex was complementary that of Pancreatin.Pancreatin/Protamex hydrolysates had the most complicated molecular mass profile and highest protein recovery 92.34% after 24h hydrolysis.During Pancreatin/Protamex extensive hydrolysis later time, peptides especially for high molecular weight（ 〉 15kDa） and for containing more hydrophobic amino acids, aggregated becoming to insoluble,decreased protein recovery（PR）.