热处理大豆球蛋白的体外消化稳定性In vitro digestion stability of soybean globulin after heating treatment

为了有效评估大豆球蛋白抗原性变化，对热处理后的大豆球蛋白进行体外模拟消化实验，考察其体外消化稳定性。首先采用碱溶酸沉法从脱脂大豆粉中提取大豆球蛋白，然后将其经400 MPa超高静压处理15 min后进行加热（70、90、110、130 ℃）处理20 min，然后进行体外模拟消化实验，采用SDS-PAGE、邻苯二甲醛（OPA）法和间接竞争酶联免疫（ELISA）法研究消化过程中大豆球蛋白的蛋白质分子质量、水解度和抗原性的变化。结果表明：经体外模拟消化实验后，与未处理样品相比，不同温度热处理后大豆球蛋白的蛋白质条带逐渐变浅，生成更多的小分子蛋白；在胃消化过程中，未处理和热处理大豆球蛋白的水解度逐渐增强，在肠消化过程中，经过90、110、130 ℃热处理的大豆球蛋白水解度总体先增加后降低；与未处理的大豆球蛋白相比，热处理大豆球蛋白经过胃肠消化后抗原抑制率显著下降，最低可从87%降至4%。大豆球蛋白经过热处理，通过胃肠消化后可显著降低其抗原性。 In order to effectively evaluate the changes of antigenicity of soybean globulin, in vitro simulated digestion experiments on heating treated soybean globulin were carried out and its in vitro digestion stability was investigated. Soybean globulin was extracted from defatted soybean powder by alkali-soluble and acid-precipitation method. It was treated with ultra-high static pressure of 400 MPa for 15 min and then heated (70, 90, 110, 130 ℃) for 20 min for in vitro simulated digestion experiment. The changes of molecular weight, degree of hydrolysis and antigenicity during digestion were studied by SDS-PAGE, o-phthalaldehyde(OPA) method and indirect competitive enzyme-linked immunosorbent assay (ELISA). The results showed that after the in vitro simulated digestion experiment, compared with the untreated samples, the protein bands treated at different temperatures gradually became shallower and more small molecule proteins were generated. In the process of gastric digestion, the degree of hydrolysis of protein before and after treatment gradually increased, and in the process of intestinal digestion, the degree of hydrolysis of protein treated at 90,110,130 ℃increased first and then decreased. Compared with the untreated protein, the antigen inhibition rate of heat treated soybean globulin decreased from 87% to 4% after digestion, which significantly reduced its antigenicity. After heating treatment of soybean globulin, its antigenicity was reduced significantly through gastrointestinal digestion.