虾夷扇贝生殖腺凝胶状酶解物的流变特性

Rheological properties of protein hydrolysates with gel properties from scallop(Patinopecten yessoensis) male gonads

本文对虾夷扇贝生殖腺凝胶状酶解物的流变特性进行了研究,为虾夷扇贝的综合利用奠定研究基础。以虾夷扇贝雄性生殖腺为原料,选用木瓜蛋白酶作为工具酶,通过SDS-PAGE分析酶解过程中蛋白质分子量的变化,利用流变仪考察酶解液的流变特性;利用脱氧核糖核酸酶(DNaseⅠ)在前期对样品进行孵育,探讨DNA分子对于其流变特性的作用影响。结果显示,虾夷扇贝雄性生殖腺经木瓜蛋白酶(30000 U/g蛋白)酶解15~180 min后,蛋白质发生显著降解。在不同流变仪扫描模式下,酶解液的储存模量G'、损耗模量G″、黏度η、复数黏度η*均明显高于未酶解样品。酶解3 h时,应变扫描中,应变为1%时,G'、G″分别达到了188.9 Pa和17.9 Pa;频率扫描中,频率为0.1 Hz时,η*达到230.9 Pa·s。经DNaseⅠ处理后,酶解液流变参数(G'、G″及η*)显著降低,但略高于未酶解样品。上述结果说明,虾夷扇贝生殖腺凝胶状酶解物以弹性占主导,具有明显的剪切稀化现象,且其流变特性可能与肽分子和DNA分子有关。

In order to provide a foundation for comprehensive utilization of scallop （ Patinopecten yessoensis ）, the rheological properties of hydrolysates from scallop （Patinopecten yessoensi~ ） gonad （ SMGHs ） were studied. The hydrolysates were obtained from scallop male gonads（SMGs） by using papain as a tool enzyme.The changes in molecular mass of proteins were investigated by sodium dodecyl sulfate- polyaerylamide gel electrophoresis （SDS- PAGE ）. The rheological properties of SMGHs were determined by rheometer.The effect of DNA on rheologieal properties of SMGHs was also investigated by incubated with DNase I. The results showed that the proteins of SMGs were significantly degraded after hydrolysis with papain at a dosage of 30000 U/g protein for 15-180 min.Under various sweep models, the values of storage modulus G＇, loss modulus G″, viscosity η^＊ , complex viscosity η^＊ of SMGHs were obvious higher than those of SMGs. After hydrolysis for 3 h, the initial values of G′,G″during oscillation strain scanning were up to 188.9,17.9 Pa at oscillation strain of 1%, respectively.The value of η^＊ was 230.9 Pa-s at frequency of 0.1 Hz.The rheological properties（ G′、G″η^＊ ）of SMGHs decreased significantly, but slightly higher than those of SMGs, by treatment with DNase I . These results suggest that the elastic property is dominant in SMGHs exhibiting obvious shear thinning effect.Moreover,the rheological properties of SMGHs might be related to peptides and DNA molecule.