PDF(Pubmed)
Abstract：
Staphylococcus aureus and Staphylococcus epidermidis stand as notorious threats to human beings owing to the myriad of infections they cause. The bacteria readily form biofilms that help in withstanding the effects of antibiotics and the immune system. Intending to combat the biofilm formation and reduce the virulence of the pathogens, we investigated the effects of carotenoids, crocetin, and crocin, on four Staphylococcal strains. Crocetin was found to be the most effective as it diminished the biofilm formation of S. aureus ATCC 6538 significantly at 50 µg/mL without exhibiting bactericidal effect (MIC >800 µg/mL) and also inhibited the formation of biofilm by MSSA 25923 and S. epidermidis at a concentration as low as 2 µg/mL, and that by methicillin-resistant S. aureus MW2 at 100 µg/mL. It displayed minimal to no antibiofilm efficacy on the Gram-negative strains Escherichia coli O157:H7 and Pseudomonas aeruginosa as well as a fungal strain of Candida albicans. It could also curb the formation of fibrils, which partly contributes to the biofilm formation in S. epidermidis. Additionally, the ADME analysis of crocetin proclaims how relatively non-toxic the chemical is. Also, crocetin displayed synergistic antibiofilm characteristics in combination with tobramycin. The presence of a polyene chain with carboxylic acid groups at its ends is hypothesized to contribute to the strong antibiofilm characteristics of crocetin. These findings suggest that using apocarotenoids, particularly crocetin might help curb the biofilm formation by S. aureus and S. epidermidis.
摘要：
金黄色葡萄球菌和表皮葡萄球菌由于它们引起的无数感染而对人类构成臭名昭著的威胁。细菌容易形成生物膜，有助于抵抗抗生素和免疫系统的影响。旨在对抗生物膜的形成并降低病原体的毒力，我们研究了类胡萝卜素的作用，番红花素,和Crocin,四种葡萄球菌菌株。西红花素被发现是最有效的，因为它在50µg/mL时显著减少了金黄色葡萄球菌ATCC6538的生物膜形成，而不表现出杀菌作用（MIC>800µg/mL），并且还抑制了MSSA25923和表皮葡萄球菌在低至2µg/mL的浓度下的生物膜形成。和耐甲氧西林金黄色葡萄球菌MW2在100µg/mL。它对革兰氏阴性菌株大肠杆菌O157：H7和铜绿假单胞菌以及白色念珠菌的真菌菌株显示出最小的抗生物膜功效。它还可以抑制原纤维的形成，这在一定程度上有助于表皮葡萄球菌的生物膜形成。此外,对番红花酸的ADME分析表明，这种化学物质是如何相对无毒的。此外，藏红花素与妥布霉素联合应用具有协同抗生物膜特性。假设在其末端具有羧酸基团的多烯链的存在有助于番红花酸的强抗生物膜特性。这些发现表明，使用载脂蛋白类胡萝卜素，特别是番红花素可能有助于抑制金黄色葡萄球菌和表皮葡萄球菌的生物膜形成。
