研究了3种不同脱乙酰度蚕蛹壳聚糖对9种供试菌的抑菌效果。结果表明:3种壳聚糖对蜡状芽孢杆菌、鼠伤寒杆菌、枯草芽孢杆菌、白色念珠球菌、绿脓假单胞菌、大肠杆菌和金黄色葡萄球菌有明显的抑制作用,对巨大芽孢杆菌和嗜热脂肪芽孢杆菌的抑制作用不明显。随着壳聚糖溶液浓度的增大,其抑菌能力也增强。3种壳聚糖的抑菌活性为:脱乙酰度为95.96%的壳聚糖>脱乙酰度为86.45%的壳聚糖>脱乙酰度为78.12%的壳聚糖。壳聚糖的抑菌活性呈现随pH降低而增加的趋势,当pH值在pH 4.0～5.0,壳聚糖对所有供试菌均能完全抑制。高脱乙酰度蚕蛹壳聚糖作为热加工食品的防腐剂,可稳定保持其抑菌防腐性能。

In this paper,three chitosans whose deacetylated degree are different were examined against nine bacteria at different conditions by oxford cup method.The results showed that three chitosans had obvious antimicrobial activities on Bacillus cereus,Bacillus typhi murium,Bacillus subtilis,candida albillus,Bacillus pyocyaneus,Escherichia coli and Staphylococcus aureus,and unconspicuous antimicrobial activities on Bacillus megaterium de Bary and Bacillus stearothermophilus Donk.Antimicrobial activities of chitosans enhanced with the solution concentration at the high concentrations.The orders of of antimicrobial activities of different deacetylated degree chitosan were chitosan whose deacetylated degree is 95.96%> chitosan whose deacetylated degree is 86.45%> chitosan whose deacetylated degree is 78.12%.Chitosans showed stronger antimicrobial activities at low pH value.Chitosans can suppress the bacteria completely when the pH was 3.0-5.0.High deacetylated degree chitosan from silkworm chrysalis can keep its antimicrobial activity steadily as preservative in hot-working foods.