Biofilm Biology Laboratory, Centre for Research on Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed University, Tirumalaisamudram, Thanjavur, 613 401, Tamil Nadu, India.
School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur, 613 401, Tamil Nadu, India.
Food Chem Toxicol. 2018 Aug;118:733-744. doi: 10.1016/j.fct.2018.06.017. Epub 2018 Jun 13.
Multidrug-resistant (MDR) Staphylococcus aureus is a major cause of biofilm-associated and indwelling device related infections. The present study explores the anti-virulent and antibiofilm potency of chitosan extracted from the shells of the marine crab Portunus sanguinolentus against Methicillin Resistant Staphylococcus aureus (MRSA). The chemical characterization results revealed that the extracted chitosan (EC) has structural analogy to that of a commercial chitosan (CC). The extracted chitosan was found to be effective in reducing the staphyloxanthin pigment, a characteristic virulence feature of MRSA that promotes resistance to reactive oxygen species. Furthermore, Confocal laser scanning microscope (CLSM) revealed that EC exhibited a phenomenal dose dependent antibiofilm efficacy against mature biofilms of the standard as well as clinical MRSA strains and Scanning Electron Microscopy (SEM) confirmed EC had a higher efficacy in disrupting the thick Exopolysaccharide (EPS) layer than CC. Additionally, EC and CC did not have any cytotoxic effects when tested on lung epithelial cell lines. Thus, the study exemplifies the anti-virulent properties of a marine bioresource which is till date discarded as a biowaste.
耐多药金黄色葡萄球菌是生物膜相关和留置装置相关感染的主要原因。本研究探讨了从海洋蟹 Portunus sanguinolentus 的壳中提取的壳聚糖对耐甲氧西林金黄色葡萄球菌 (MRSA) 的抗毒力和抗生物膜功效。化学特性分析结果表明，提取的壳聚糖 (EC) 在结构上与商业壳聚糖 (CC) 相似。研究发现，提取的壳聚糖可有效减少金黄色葡萄球菌色素，这是 MRSA 的一个特征性毒力特征，可促进其对活性氧的抗性。此外，共聚焦激光扫描显微镜 (CLSM) 显示，EC 对标准和临床 MRSA 菌株的成熟生物膜具有显著的剂量依赖性抗生物膜功效，扫描电子显微镜 (SEM) 证实 EC 比 CC 更有效地破坏厚胞外多糖 (EPS) 层。此外，EC 和 CC 在测试肺上皮细胞系时均没有细胞毒性作用。因此，该研究例示了海洋生物资源的抗毒力特性，这些资源目前仍被当作生物废物丢弃。
