红凤菜多肽的制备及其美拉德反应产物的抗氧化性能研究

Study on the preparation of polypeptides from Gynura bicolor and the antioxidant properties of Maillard reaction products

中文关键词:  红凤菜  蛋白  酶解  多肽  抗氧化  美拉德反应

英文关键词:Gynura bicolor  protein  enzymolysis  polypeptide  antioxidant  Maillard reaction

中文摘要:

      目的 优化红凤菜蛋白提取工艺并制备活性多肽, 对多肽进行改性, 探讨产物的抗氧化性能, 深入开发其蛋白资源。方法 结合超声和高剪切技术, 用响应面法优化提取红凤菜中的蛋白质, 采用酶解法制备多肽并进行糖基化改性, 且研究其抗氧化性能。结果 最优条件为料液比1:47 (g:mL), 300 W超声波处理20 min, 高剪切6次, 提取温度为46.7℃, 提取时间2.5 h, 提取液pH 8.40时, 此时蛋白提取率为79.64%, 接近响应面预测值。用蛋白酶水解红凤菜蛋白制备活性肽, 以抗氧化性能为指标筛选合适的酶并优化酶解条件。用超滤膜加压过滤对水解产物进行分级, 分级产物中, Mw<1 kDa的多肽抗氧化性能最佳。红凤菜多肽与木糖进行美拉德反应后, 对1,1二苯基-2-三硝基苯肼自由基和2,2-联氮-双-3-乙基苯并噻唑啉-6-磺酸自由基的清除率分别为87.65%、80.65%, 比改性前提高了7.99%和11.37%。结论 本方法的红凤菜蛋白提取率高, 糖基化产物的抗氧化效果好。

英文摘要:

      Objective To optimize the extraction process of Gynura bicoloi protein, prepare active peptides, and then modify the peptides, explore the antioxidant properties of the products, and further develop its protein resources. Methods Combined with ultrasonic and high shear technology, response surface methodology was used to optimize the extraction of protein from Gynura bicolor. Peptides were prepared by enzymatic hydrolysis, and then was modified by glycosylation, and the antioxidant properties of the products were studied. Results The protein extraction rate was the highest when the solid-liquid ratio was 1:47 (g:mL), ultrasonic 300 W treatment for 20 min, high shear treatment for 6 times, the extraction temperature was 46.7℃, the extraction time was 2.5 h, and the pH of extraction solution was 8.40. Under the optimum conditions, the protein extraction rate was 79.64%, which was close to the predicted value of response surface experiment. The active peptides were prepared by hydrolyzing Gynura bicolor protein with protease. Taking antioxidant activity as index, the appropriate enzymes were screened and the enzymatic hydrolysis conditions were optimized. The hydrolysates were graded by pressure filtration with ultrafiltration membrane. Among the graded products, the polypeptide with Mw<1 kDa had the best antioxidant performance. After Maillard reaction of polypeptide with xylose, the clearance and 2,2-azo-bis-3-ethylbenzothiazoline 6-sulfonic acid radical were 87.65% and 80.65%, respectively, which were 7.99% and 11.37% higher than those before modification. Conclusion This method has high protein extraction rate and good antioxidant effect of glycosylated products.