克氏螯虾壳聚糖的荧光标记及其抗菌活性的研究

The Study on Labeling Chitosan from Redswamp Crayfish with Fluorescence and Its Antibacterial Activity

目的建立克氏螯虾壳聚糖的荧光标记方法并研究其抗菌活性。方法利用荧光物质5(6)-羧-四甲基罗丹明-5-马来酰亚胺按不同比例标记克氏螯虾壳聚糖,检测标记后克氏螯虾壳聚糖对大肠埃希菌及金黄色葡萄球菌的抗菌效果,并用激光共聚焦显微镜观察壳聚糖对试验菌的作用靶位。结果克氏螯虾壳聚糖与荧光物质(v/v)9∶1混合时,所得的荧光标记克氏螯虾壳聚糖对两种试验菌的抗菌活性保留50%。荧光标记克氏螯虾壳聚糖已进入细菌内部。结论控制荧光标记克氏螯虾壳聚糖抗菌活性基团的比例,不影响其抗菌的活性,可作为一种荧光探针,用于克氏螯虾壳聚糖抗菌作用靶位的研究。

Objective To establish the method to label chitosan from redswamp crayfish with fluorescence and to study its antibacterial activity. Methods The chitosan from redswamp crayfish was marked by flourescent reagent 5 （ 6 ） -Carboxy-tetramethylrhodamine-5-maleimide [ 5 （6）-TAMRA-5-maleimide] according to different ratios. Its antibacterial activity towards Escherichia. coli（ E. coll） and Staphylococcus. aureus （S. aureus） was then investigated. Laser scanning confocal microscope （LSCM） was used to determine the effective target site on tested bacteria exerted by chitoan. Results When mixed with fluorescence according to 9 ： 1 （ v/v ）, the antibacterial activity of chitosan fromredswamp crayfish marked by flourescent reagent towards both tested bacteria remained 50%, Chitosan from redswamp crayfish marked by flourescent reagent could enter the bacteria interia. Conclusion If the ratio of active group from chitosan from redswamp crayfish labeled by fluorescence could be controlled ,its antibacterial activity would not diminish. It could be used as a kind of fluorescent probe to invetigate the antibacterial target site of chitosan from redswamp crayfish.