Shazly Ahmed Behdal, He Zhiyong, El-Aziz Mahmoud Abd, Zeng Maomao, Zhang Shuang, Qin Fang, Chen Jie
State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China; Dairy Science Department, National Research Centre, Dokki 12311, Giza, Egypt.
State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, China.
Food Chem. 2017 Oct 1;232:753-762. doi: 10.1016/j.foodchem.2017.04.071. Epub 2017 Apr 13.
Buffalo and bovine caseins were hydrolysed by alcalase and trypsin to produce novel antioxidant peptides. The casein hydrolysates were purified using ultrafiltration (UF) and further characterized by RP-HPLC. The fractions produced higher antioxidant activities were identified for their peptides using LC MS/MS. All UF-VI (MW<1kDa) fractions showed higher antioxidant activity. Hydrolysate produced by alcalase for buffalo casein (UF-VI with 54.84-fold purification) showed higher antioxidant activity than that obtained by trypsin. Trypsin hydrolysate contained high amount of hydrophobic amino acids while alcalase hydrolysate consisted mainly of Ser, Arg, Ala and Leu. The antioxidant peptides identified by LC MS/MS were RELEE, MEDNKQ and TVA, EQL in buffalo casein hydrolysates produced by trypsin and alcalase, respectively. Mechanism and reaction pathways of selected antioxidant peptides with ABTS were proposed. Conclusively, buffalo casein provided antioxidant peptides similar to bovine, suggesting that buffalo casein is a novel source of antioxidant.
水牛和牛酪蛋白经碱性蛋白酶和胰蛋白酶水解，以产生新型抗氧化肽。酪蛋白水解产物通过超滤（UF）进行纯化，并通过反相高效液相色谱（RP-HPLC）进一步表征。使用液相色谱-串联质谱（LC MS/MS）鉴定产生较高抗氧化活性的级分中的肽。所有超滤-VI（分子量<1 kDa）级分均显示出较高的抗氧化活性。碱性蛋白酶水解水牛酪蛋白产生的水解产物（纯化倍数为54.84倍的超滤-VI）显示出比胰蛋白酶获得的水解产物更高的抗氧化活性。胰蛋白酶水解产物含有大量疏水氨基酸，而碱性蛋白酶水解产物主要由丝氨酸、精氨酸、丙氨酸和亮氨酸组成。通过LC MS/MS鉴定出的水牛酪蛋白水解产物中，胰蛋白酶和碱性蛋白酶分别产生的抗氧化肽为RELEE、MEDNKQ以及TVA、EQL。提出了所选抗氧化肽与ABTS的作用机制和反应途径。总之，水牛酪蛋白提供了与牛酪蛋白类似的抗氧化肽，表明水牛酪蛋白是一种新型抗氧化剂来源。
