College of Light Industry and Food Sciences, South China University of Technology , Guangzhou, Guangdong 510640, People's Republic of China.
J Agric Food Chem. 2015 Nov 4;63(43):9513-9. doi: 10.1021/acs.jafc.5b03337. Epub 2015 Oct 26.
Phytohemagglutin (PHA), purified from red kidney beans (Phaseolus vulgaris) by Affi-Gel blue affinity chromatography, was subjected to ultrahigh-pressure (UHP) treatment (150, 250, 350, and 450 MPa). The purified PHA lost its hemagglutination activity after 450 MPa treatment and showed less pressure tolerance than crude PHA. However, the saccharide specificity and α-glucosidase inhibition activity of the purified PHA did not change much after UHP treatment. Electrophoresis staining by periodic acid-Schiff (PAS) manifested that the glycone structure of purified PHA remained stable even after 450 MPa pressure treatment. However, electrophoresis staining by Coomassie Blue as well as circular dichroism (CD) and differential scanning calorimetry (DSC) assay proved that the protein unit structure of purified PHA unfolded when treated at 0-250 MPa but reaggregates at 250-450 MPa. Therefore, the hemagglutination activity tends to be affected by the protein unit structure, while the stability of the glycone structure contributed to the remaining α-glucosidase inhibition activity.
植物血球凝集素（PHA）经 Affi-Gel 蓝亲和层析从红芸豆（Phaseolus vulgaris）中纯化，经超高压（UHP）处理（150、250、350 和 450 MPa）。450 MPa 处理后，纯化的 PHA 失去了血凝活性，比粗 PHA 更不耐压。然而，UHP 处理后，纯化的 PHA 的糖特异性和α-葡萄糖苷酶抑制活性变化不大。过碘酸-Schiff（PAS）电泳染色表明，即使在 450 MPa 压力处理后，纯化的 PHA 的糖苷结构仍然稳定。然而，考马斯亮蓝电泳染色以及圆二色性（CD）和差示扫描量热法（DSC）分析证明，当在 0-250 MPa 下处理时，纯化的 PHA 的蛋白质单元结构展开，但在 250-450 MPa 下重新聚集。因此，血凝活性容易受到蛋白质单元结构的影响，而糖苷结构的稳定性有助于保持剩余的α-葡萄糖苷酶抑制活性。
