Scandorieiro Sara, Teixeira Franciele Maira M B, Nogueira Mara C L, Panagio Luciano A, de Oliveira Admilton G, Durán Nelson, Nakazato Gerson, Kobayashi Renata K T
Laboratory of Basic and Applied Bacteriology, Department of Microbiology, Center of Biological Sciences, Universidade Estadual de Londrina, Londrina 86057-970, Brazil.
Laboratory of Innovation and Cosmeceutical Technology, Department of Pharmaceutical Sciences, Center of Health Sciences, Hospital Universitário de Londrina, Londrina 86038-350, Brazil.
Antibiotics (Basel). 2023 Apr 14;12(4):756. doi: 10.3390/antibiotics12040756.
Resistant bacteria may kill more people than COVID-19, so the development of new antibacterials is essential, especially against microbial biofilms that are reservoirs of resistant cells. Silver nanoparticles (bioAgNP), biogenically synthesized using , combined with oregano derivatives, present a strategic antibacterial mechanism and prevent the emergence of resistance against planktonic microorganisms. Antibiofilm activity of four binary combinations was tested against enteroaggregative (EAEC) and carbapenemase-producing (KPC): oregano essential oil (OEO) plus bioAgNP, carvacrol (Car) plus bioAgNP, thymol (Thy) plus bioAgNP, and Car plus Thy. The antibiofilm effect was accessed using crystal violet, MTT, scanning electron microscopy, and anti-quorum-sensing assays. All binary combinations acted against preformed biofilm and prevented its formation; they showed improved antibiofilm activity compared to antimicrobials individually by reducing sessile minimal inhibitory concentration up to 87.5% or further decreasing biofilm metabolic activity and total biomass. Thy plus bioAgNP extensively inhibited the growth of biofilm in polystyrene and glass surfaces, disrupted three-dimensional biofilm structure, and quorum-sensing inhibition may be involved in its antibiofilm activity. For the first time, it is shown that bioAgNP combined with oregano has antibiofilm effect against bacteria for which antimicrobials are urgently needed, such as KPC.
耐药细菌可能比新冠病毒杀死更多人，因此开发新型抗菌药物至关重要，尤其是针对作为耐药菌储存库的微生物生物膜。利用生物合成法制备的银纳米颗粒（bioAgNP）与牛至衍生物相结合，呈现出一种具有战略意义的抗菌机制，并可防止对浮游微生物产生耐药性。测试了四种二元组合对聚集性大肠杆菌（EAEC）和产碳青霉烯酶菌（KPC）的抗生物膜活性：牛至精油（OEO）加bioAgNP、香芹酚（Car）加bioAgNP、百里香酚（Thy）加bioAgNP以及Car加Thy。使用结晶紫、MTT、扫描电子显微镜和抗群体感应测定法评估抗生物膜效果。所有二元组合均对预先形成的生物膜起作用并阻止其形成；与单独使用抗菌药物相比，它们通过将固着态最小抑菌浓度降低高达87.5%，或进一步降低生物膜代谢活性和总生物量，显示出增强的抗生物膜活性。Thy加bioAgNP广泛抑制聚苯乙烯和玻璃表面生物膜的生长，破坏三维生物膜结构，群体感应抑制可能参与其抗生物膜活性。首次表明，bioAgNP与牛至组合对迫切需要抗菌药物的细菌（如KPC）具有抗生物膜作用。
