title: Cinnamon bark oil and its components inhibit biofilm formation and toxin production.
abstract: The long-term usage of antibiotics has resulted in the evolution of multidrug resistant bacteria, and pathogenic biofilms contribute to reduced susceptibility to antibiotics. In this study, 83 essential oils were initially screened for biofilm inhibition against Pseudomonas aeruginosa. Cinnamon bark oil and its main constituent cinnamaldehyde at 0.05% (v/v) markedly inhibited P. aeruginosa biofilm formation. Furthermore, cinnamon bark oil and eugenol decreased the production of pyocyanin and 2-heptyl-3-hydroxy-4(1H)-quinolone, the swarming motility, and the hemolytic activity of P. aeruginosa. Also, cinnamon bark oil, cinnamaldehyde, and eugenol at 0.01% (v/v) significantly decreased biofilm formation of enterohemorrhagic Escherichia coli O157:H7 (EHEC). Transcriptional analysis showed that cinnamon bark oil down-regulated curli genes and Shiga-like toxin gene stx2 in EHEC. In addition, biodegradable poly(lactic-co-glycolic acid) film incorporating biofilm inhibitors was fabricated and shown to provide efficient biofilm control on solid surfaces. This is the first report that cinnamon bark oil and its components, cinnamaldehyde and eugenol, reduce the production of pyocyanin and PQS, the swarming motility, and the hemolytic activity of P. aeruginosa, and inhibit EHEC biofilm formation.
authors.affiliation: School of Chemical Engineering, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Yong-Guy
authors.initials: YG
authors.lastname: Kim
authors.affiliation: School of Chemical Engineering, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Jin-Hyung
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Nareso Research Center, Seoho-ro 89, Suwon 441-853, Republic of Korea.
authors.forename: Soon-Il
authors.initials: SI
authors.lastname: Kim
authors.affiliation: School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Republic of Korea.
authors.forename: Kwang-Hyun
authors.initials: KH
authors.lastname: Baek
authors.affiliation: School of Chemical Engineering, Yeungnam University, Gyeongsan 712-749, Republic of Korea. Electronic address: jtlee@ynu.ac.kr.
authors.forename: Jintae
authors.initials: J
authors.lastname: Lee
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001427:Bacterial Toxins / Q000235:genetics*; D018441:Biofilms / Q000187:drug effects*; D019453:Escherichia coli O157 / Q000187:drug effects*; D005054:Eugenol / Q000494:pharmacology; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects*; D009822:Oils, Volatile / Q000737:chemistry / Q000494:pharmacology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects*
chemical_list: D000900:Anti-Bacterial Agents; D001427:Bacterial Toxins; D009822:Oils, Volatile; C510046:cinnamon oil, bark; D005054:Eugenol
keywords: Biofilm formation; Cinnamaldehyde; Cinnamon bark oil; Eugenol; Hemolysis; Toxin production