Porcine myofibrillar protein

Saiga, A.,Tanabe, S.,and Nishimura, T. 2003. Antioxidant activity of peptides obtained from porcine myofibrillar proteins by protease treatment. I. Agric. Food Chem.,51, 3661-3667. 

Meat Porcine myofibrillar proteins Hydrolysis with papain Acidic peptides DSGVT, lEAEGE, DAQEKLE, EELDNALN, VPSIDDQEELM Saiga et al. (2003)... 

Antioxidative Peptides in Porcine Myofibrillar Protein Hydrolysates by Protease Treatment... 

In present study, we investigated antioxidant activity of porcine myofibrillar protein hydrolysates obtained enzymatic treatment in the peroxidation system of linolenic aqueous induced by Fe. Furthermore, antioxidant peptides are isolated from its hydrolysate. 

A proteolytic hydrolysate of porcine myofibrillar proteins was hydrolyzed in 6 N HCl at 110 C for 24h. Amino acid composition of peptides in the hydrolysate was analyzed with an amino acid analyzer (Shimazu Co, Kyoto Japan). 

Antioxidative activities of the hydrolysates from porcine myofibrillar protein were measured in a linolenic acid oxidation system The hydrolysates at the concentration of 0.02, 0.2 and 2% exhibited antioxidative activities. All hydrolysates exhibited stronger antioxidative activity, as the concentration was higher in the production of hydroperoxides. On the other hand, the addition of 0.2% hydrolysate suppressed the production of TEARS most strongly, and the antioxidative activity in the addition of 2% hydrolysate was lower than that of 0.2% in the method of TEARS. It is well known that 2-thiobarbituric acid (TEA) reacts with aldehyde compounds including malondialdehyde (MDA) formed by Upid peroxidation. Two percent hydrolysates contained a lot of amino confounds including free amino acids and peptides. Therefore, the production of aldehyde compounds seems to be accelerated by amino-carbonyl reaction between hydrolysate and lipid in lipid peroxidation system including 2% hydrolysate. This might be the reason why the antioxidative activity of 2% hydrolysate was lower than that of 0.2 % hydrolysate in the method of TEARS. 

Dayton, W., Goll, D., Zeece, M., Robson, R., Reville, W., 1976, A Ca2+-activated protease possibly involved in myofibrillar protein turnover. Purification from porcine muscle, Biochemistry, 15, 2150-2158... 

Kim (94) has demonstrated the degradation of myofibrillar proteins purified from porcine semimembranosus muscle by porcine leukocyte lysosomal proteinases. Troponin treated with leukocyte lysosomal pro-teinases mixed with tropomyosin did not result in the normal increase in viscosity of this system. The emulsifying capacity of aetomyosin treated with lysosomal proteinases at 37 °C and pH 7 for 12 hr was higher than that of aetomyosin incubated without enzymes. On the other hand, aetomyosin treated with papain had low emulsifying capacity because of extensive degradation. Control aetomyosin incubated at 37 °C, pH 7 for 12 hr formed a gel after removal of KC1, but aetomyosin treated with lysosomal proteinases or papain did not gel. 

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