Study on transglutaminase used as a milk coagulating agent and a blood hemostat

• Main Authors: Tai-Li Hsueh, 薛台莉
• Other Authors: Ming-Tsao Chen
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/37410461326899040031

碩士 === 國立中興大學 === 畜產學系 === 89 === Transglutaminase（TGase, FXIIIa）has been applied in food to improve the functional ability of food protein and the nutrition of products. No much information about application of TGase on milk products was published in the paper reviews. FXIIIa and fibrinogen are important blood clotting factors during the blood coagulating procedure. The purpose of this research was to evaluate the efficiency of pig plasma TGase and TGase from Streptoverticillium kentuckense CCRC 12429 as a milk coagulating agent and a blood hemostat, respectively. The results showed that pig plasma TGase（PTG）after precipitation with 40﹪ammonium sulfate and lyophilization had 2.14 units/mg specific activity, 7.38 purified multiples folds and 49.84﹪of yield, individually. The crude TGase from Streptoverticillium kentuckense CCRC 12429（MTG）had 0.48 units/mg specific activity, after precipitation with 55~75﹪ammonium sulfate, the TGase specific activity increased up to 1.42 units/mg, the purified multiples was 2.96 folds, and the yield was 43.23%. Furthermore, the sample after dialysis, the specific activity was 1.10 units/mg, the purified multiple was 2.29 folds, and the yield was 31.26%. A 17 gram fibrinogen powders can be extracted from 5 liter fresh pig plasma and its powder was light brown The aspect of milk coagulating test, TGase from S. kentuckense CCRC 12429 did not induce milk coagulation. Skim milk and fresh milk with 100 units PTG as well as milk protein solution（Sentosa）with 80 units PTG, incubated at 37℃ for 3 hours had the best rheological properties of milk curd. With the increasing of skim milk solid, incubation time and PTG level, the rheological properties of milk curd significantly increased（p＜0.05）. In electrophoresis, a lower mono-milk protein content and higher oligomer content level was observed in milk protein solution（Sentosa）. These content were changed by PTG level, incubation time and milk solid content. The observation of scanning electron microscopy（SEM）, with the increase of the PTG additions, the microstructure of milk curd was firmer and the holes of the microstructure was smaller. The aspect of blood coagulating experiment, the blood coagulating time for MTG, pig plasma fibrinogen (PF), mixture of MTG and PF, PTG and mixture of PTG and PF as a blood hemostat was 206.25, 181.60, 170.00, 167.83 and 149.50 sec., individually. This result indicated that mixture of PTG and PF had the best hemostatic effect in all blood hemostats and combination of PTG and PF had better hemostatic effect than single in this study. The microstructure of blood clot maybe can be used to explain this phenomenon. The microstructure of blood clot with PTG and PF as a blood hemostat was firmer than that of single MTG, PF or mixture. And some fiber-like structure was also found by observation of SEM. In conclusion, PTG used as a milk coagulating agent or a blood hemostat was better than MTG due to a higher specificity on milk and blood.