Laboratory of Biotechnology, Institute of Animal Nutrition, Northeast Agricultural University, Harbin 150030, China.
Biomed Res Int. 2013;2013:278927. doi: 10.1155/2013/278927. Epub 2012 Dec 27.
For utilizing the blood cells (BCs) effectively, enzymatic hydrolysis was applied to produce the enzymatically hydrolyzed blood cells (EHBCs) by using a neutral protease as a catalyst. The results of the single-factor experiments showed optimal substrate concentration, enzyme to substrate ratio (E/S), pH, temperature, and incubation period were 1.00%, 0.10, 7.00, 50.00°C, and 12.00 h, respectively. The optimized hydrolysis conditions from response surface methodology (RSM) were pH 6.50, E/S 0.11, temperature 45.00°C, and incubation period 12.00 h. Under these conditions (substrate concentration 1.00%), the degree of hydrolysis (DH) was 35.06%. The free amino acids (FAAs) content of the EHBCs (35.24%) was 40.46 times higher than BCs while the total amino acids (TAAs) content was lower than BCs. The scores of lysine (human 0.87; pig 0.97), valine (human 1.42; pig 1.38), leucine (human 1.50; pig 1.90), tyrosine (human 0.84; pig 1.09), and histidine (human 2.17; pig 2.50) indicated that the EHBCs basically fulfilled the adult human and pig nutritional requirements. The calculated protein efficiency ratios (C-PERs) of the EHBCs were 3.94, 6.19, 21.73, and 2.04. In summary, the EHBCs were produced successfully with optimized conditions and could be a novel protein source for humans and pigs.
为了有效利用血细胞 (BCs)，采用中性蛋白酶作为催化剂进行酶解，制备酶解血细胞 (EHBCs)。单因素实验结果表明，最佳的底物浓度、酶与底物比 (E/S)、pH 值、温度和孵育时间分别为 1.00%、0.10、7.00、50.00°C 和 12.00 h。响应面法 (RSM) 的优化水解条件为 pH 6.50、E/S 0.11、温度 45.00°C 和孵育时间 12.00 h。在这些条件下 (底物浓度 1.00%)，水解度 (DH) 为 35.06%。EHBCs 的游离氨基酸 (FAA) 含量 (35.24%)比 BCs 高 40.46 倍，而总氨基酸 (TAA) 含量则低于 BCs。赖氨酸 (人 0.87；猪 0.97)、缬氨酸 (人 1.42；猪 1.38)、亮氨酸 (人 1.50；猪 1.90)、酪氨酸 (人 0.84；猪 1.09)和组氨酸 (人 2.17；猪 2.50)的得分表明，EHBCs 基本满足成人和猪的营养需求。EHBCs 的计算蛋白质效率比 (C-PERs) 分别为 3.94、6.19、21.73 和 2.04。总之，EHBCs 的制备条件得到了优化，可以作为人类和猪的一种新型蛋白质来源。
