Microorganisms which adhere to the surfaces of indwelling medical implants develop into a sessile microbial community to form monomicrobial or polymicrobial biofilms. Staphylococcus epidermidis and Candida albicans are the most common pathogens co-isolated from device mediated infections. Hence development of catheters coated with anti-fouling substances is of great interest. In this current study, chitosan, extracted from the shells of marine crab Portunus sanguinolentus was coated over the surface of the urinary catheters and checked for its efficacy to inhibit the adherence of both mono and mixed species biofilms. The Extracted Chitosan (EC) coated catheters showed profound activity in reducing the preformed biofilms and the other virulence factors of the pathogens like slime production in S. epidermidis and yeast to hyphal swtich in C. albicans. Furthermore, qPCR analysis showed that EC could downregulate the virulence genes in both the pathogens when grown as monospecies and mixed species biofilms.

附着在留置医疗植入物表面上的微生物发展成无柄微生物群落，从而形成单微生物或多微生物生物膜。表皮葡萄球菌和白色念珠菌是从设备介导的感染中共分离出的最常见病原体。因此，非常需要开发涂覆有防污物质的导管。在本研究中，壳聚糖是从海生螃蟹Portunus sanguinolentus的壳中提取的将其涂覆在导尿管的表面上，并检查其抑制单种和混合物种生物膜粘附的功效。提取的脱乙酰壳多糖（EC）涂层导管在减少预先形成的生物膜和病原体的其他毒力因子（如表皮葡萄球菌的粘液产生和酵母到白色念珠菌的菌丝菌丝）中显示出深远的活性。此外，qPCR分析表明，当以单物种和混合物种生物膜形式生长时，EC可以下调两种病原体中的毒力基因。