【摘要】 溶菌酶活性易受食品组分和环境因素影响。研究了3种取代度的羧甲基纤维素与溶菌酶之间的静电相互作用,考察在不同温度、pH值和离子强度条件下,羧甲基纤维素对溶菌酶抑菌活性的影响。结果表明:取代度为0.7和0.9的羧甲基纤维素可提高溶菌酶活性,取代度为1.2的可降低溶菌酶活性。由于取代度越高,与溶菌酶的静电相互作用越强,溶菌酶的抑菌性随着羧甲基纤维素取代度的增加而逐渐降低。由于溶菌酶与羧甲基纤维素相互作用形成较大粒子,复合物中溶菌酶的热稳定性、pH稳定性均有所降低。Na~+会抑制溶菌酶的酶活且会使溶菌酶/羧甲基纤维素复合物解离,酶活逐渐恢复至单独溶菌酶酶活。并且进一步通过对2种革兰氏阳性菌(金黄色葡萄球菌、枯草芽孢杆菌)和2种革兰氏阴性菌(大肠杆菌、阴沟肠杆菌)的抑菌圈实验证明,羧甲基纤维素与溶菌酶复合后,低取代度的羧甲基纤维素能提高对革兰氏阳性菌的抑制作用;而且,和游离溶菌酶比较,羧甲基纤维素/溶菌酶复合物对大肠杆菌抑制作用增强。更多还原

【Abstract】 Lysozyme activity was easily affected by food composition and environmental factors. The electrostatic interaction between three degree of substitution carboxymethyl cellulose and lysozyme was studied in this paper. The effects of carboxymethyl cellulose on the bacteriostatic activity of lysozyme were investigated under different temperature pH and ionic strength. The results showed that carboxymethyl cellulose with a degree of substitution of 0.7 and 0.9 could increase lysozyme activity and decrease the activity of lysozyme when the degree of substitution was 1.2. The higher the degree of substitution, the stronger the electrostatic interaction between lysozyme and lysozyme. The bacteriostasis of lysozyme decreased with the increase of the degree of substitution of carboxymethyl cellulose. Because lysozyme interacts with carboxymethyl cellulose to form larger particles, the thermal stability and pH stability of lysozyme in the complex decrease. Na can inhibit lysozyme activity and dissociate lysozyme/carboxymethyl cellulose complex. Enzyme activity gradually recovered to lysozyme activity alone. Furthermore, the inhibition circle experiments of two Gram-positive bacteria(Staphylococcus aureus, Bacillus subtilis) and two Gram-negative bacteria(Escherichia coli, Enterobacter cloacae) proved that carboxymethyl cellulose was combined with lysozyme. The low degree of substitution of carboxymethyl cellulose could increase the inhibitory effect on Gram-positive bacteria, and the inhibitory effect of carboxymethyl cellulose/lysozyme complexes on Escherichia coli was stronger than that of free lysozyme.更多还原