【摘要】 利用海藻多糖(SA)良好的成膜保水性和L-半胱氨酸(L-cys)良好的抑菌、抗氧化性,通过化学改性法制备了巯基含量高达328.27μmol/g的L-cys改性SA(SA-cys)。采用稀释平板计数法的研究表明:在被测试范围内,L-cys对革兰氏阴性大肠杆菌、蜡样芽孢杆菌、革兰氏阳性金黄色葡萄球菌均有很好的抑菌性;SA-cys对革兰氏阴性大肠杆菌、蜡样芽孢杆菌均有较好的抑菌效果,最大抑菌率分别为100.00%,77.24%,对革兰氏阳性金黄色葡萄球菌的最大抑菌率只有61.26%;而SA对3种菌株的最大抑菌率均在40.75%以下,抑菌效果最差。因此,SA-cys在很大程度上综合了L-cys和SA的优势,拓展了SA在果蔬保鲜领域的应用范围。更多还原

【Abstract】 L-sodium alginate-cysteine(SA-cys)derivative is synthesized by chemical modification based on the film-forming and water retention of sodium alginate(SA)as well as the antibacterial and antioxidant properties of L-cysteine(L-cys),whose sulfhydryl content can reach 328.27 μmol/g. The results of dilution plate counting method show that: within the testing L-cys performs antibacterial effect on Bacillus Cereus, Escherichia coli(Gram-negative),and Staphylococcus aureus(Gram-positive);the maximum inhibition rate of SA-cys for Escherichia coli(Gram-negative)and Bacillus Cereus are 100.00% and 77.24% respectively, while that of Gram-positive Staphylococcus aureus is only 61.26%;the maximum inhibition rate of SA on three strains are below 40.75%, indicating worst antibacterial effect. Therefore, SA-sys integrates the superiority of L-cys and SA to expand the application range of SA in fresh keeping for fruits and vegetables.更多还原