Jung Kyung-Hun, Choi Ye-Chul, Chun Ji-Yeon, Min Sang-Gi, Hong Geun-Pyo
Department of Bio-Industrial Technologies, Konkuk University, Seoul 143-701, Korea.
Department of Food Bioengineering, Jeju National University, Jeju 690-756, Korea.
Korean J Food Sci Anim Resour. 2014;34(2):151-7. doi: 10.5851/kosfa.2014.34.2.151. Epub 2014 Apr 30.
This study investigated the effects of three proteases (trypsin, pepsin and chymotrypsin) on the hydrolysis efficiency of porcine placenta and the molecular weight (Mw) distributions of the placental hydrolysates. Because placenta was made up of insoluble collagen, the placenta was gelatinized by applying thermal treatment at 90 ℃ for 1 h and used as the sample. The placental hydrolyzing activities of the enzymes at varying concentrations and incubation times were determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and gel permeation chromatography (GPC). Based on the SDS-PAGE, the best placental hydrolysis efficiency was observed in trypsin treatments where all peptide bands disappeared after 1 h of incubation as compared to 6 h of chymotrypsin. Pepsin hardly hydrolyzed the placenta as compared to the other two enzymes. The Mw distribution revealed that the trypsin produced placental peptides with Mw of 106 and 500 Da. Peptides produced by chymotrypsin exhibited broad ranges of Mw distribution (1-20 kDa), while the pepsin treatment showed Mw greater than 7 kDa. For comparisons of pre-treatments, the subcritical water processing (37.5 MPa and 200 ℃ of raw placenta improved the efficiency of tryptic digestions to a greater level than that of a preheating treatment (90 ℃ for 1 h). Consequently, subcritical water processing followed by enzymatic digestions has the potential of an advanced collagen hydrolysis technique.
本研究考察了三种蛋白酶（胰蛋白酶、胃蛋白酶和糜蛋白酶）对猪胎盘水解效率及胎盘水解产物分子量（Mw）分布的影响。由于胎盘由不溶性胶原蛋白组成，因此将胎盘在90℃热处理1小时使其胶化，并用作样品。通过十二烷基硫酸钠聚丙烯酰胺凝胶电泳（SDS-PAGE）和凝胶渗透色谱法（GPC）测定不同浓度和孵育时间下酶的胎盘水解活性。基于SDS-PAGE，在胰蛋白酶处理中观察到最佳的胎盘水解效率，与糜蛋白酶处理6小时相比，孵育1小时后所有肽带均消失。与其他两种酶相比，胃蛋白酶几乎不水解胎盘。Mw分布显示，胰蛋白酶产生的胎盘肽Mw为106和500 Da。糜蛋白酶产生的肽表现出较宽的Mw分布范围（1-20 kDa），而胃蛋白酶处理显示Mw大于7 kDa。为了比较预处理方法，亚临界水处理（37.5 MPa和200℃）对生胎盘进行处理，与预热处理（90℃1小时）相比，能将胰蛋白酶消化效率提高到更高水平。因此，亚临界水处理后进行酶消化具有成为一种先进的胶原蛋白水解技术的潜力。
