title: Photodynamic effect of curcumin on Vibrio parahaemolyticus.
abstract: Vibrio parahaemolyticus (V. parahaemolyticus) is currently a major cause of bacterial diarrhoea associated with seafood consumption. The objective of this study was to determine the inactivation effect of curcumin-mediated photodynamic action on V. parahaemolyticus. First of all, V. parahaemolyticus suspended in PBS buffer was irradiated by a visible light from a LED light source with an energy density of 3.6J/cm(2). Colony forming units (CFU) were counted and the viability of V. parahaemolyticus cells was calculated after treatment. Singlet oxygen ((1)O2) production after photodynamic action of curcumin was evaluated using 9,10-Anthracenediyl-bis (methylene) dimalonic acid (ADMA). Bacterial outer membrane protein was extracted and analyzed using electrophoresis SDS-PAGE. DNA and RNA of V. parahaemolyticus were also extracted and analyzed using agarose gel electrophoresis after photodynamic treatment. Finally, the efficacy of photodynamic action of curcumin was preliminarily evaluated in the decontamination of V. parahaemolyticus in oyster. Results showed that the viability of V. parahaemolyticus was significantly decreased to non-detectable levels over 6.5-log reductions with the curcumin concentration of 10 and 20μM. Photodynamic action of curcumin significantly increased the singlet oxygen level with the curcumin concentration of 10μM. Notable damage was found to bacterial outer membrane proteins and genetic materials after photodynamic treatment. Photodynamic action of curcumin reduced the number of V. parahaemolyticus contaminating in oyster to non-detectable level. Our findings demonstrated that photodynamic action of curcumin could be a potentially good method to inactivate Vibrio parahaemolyticus contaminating in oyster.
authors.affiliation: Laboratory of Food Science and Human Health, College of Food Science and Engineering, Ocean University of China, Qingdao, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Wu
authors.affiliation: Key Laboratory of Mariculture, Ministry of Education, College of Food Science and Engineering, Ocean University of China, Qingdao, China.
authors.forename: Haijin
authors.initials: H
authors.lastname: Mou
authors.affiliation: Laboratory of Food Science and Human Health, College of Food Science and Engineering, Ocean University of China, Qingdao, China.
authors.forename: Changhu
authors.initials: C
authors.lastname: Xue
authors.affiliation: School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, China.
authors.forename: Albert Wingnang
authors.initials: AW
authors.lastname: Leung
authors.affiliation: School of Chinese Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong, China. Electronic address: xcshan@163.com.
authors.forename: Chuanshan
authors.initials: C
authors.lastname: Xu
authors.affiliation: Laboratory of Food Science and Human Health, College of Food Science and Engineering, Ocean University of China, Qingdao, China. Electronic address: tangqingjuan@ouc.edu.cn.
authors.forename: Qing-Juan
authors.initials: QJ
authors.lastname: Tang
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D003474:Curcumin / Q000008:administration & dosage*; D003666:Decontamination / Q000379:methods; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D005506:Food Contamination / Q000517:prevention & control*; D005511:Food Handling / Q000379:methods; D006801:Humans; D008027:Light; D010125:Ostreidae / Q000187:drug effects / Q000382:microbiology* / Q000528:radiation effects; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000008:administration & dosage; D014736:Vibrio parahaemolyticus / Q000187:drug effects* / Q000502:physiology / Q000528:radiation effects*
chemical_list: D000900:Anti-Bacterial Agents; D017319:Photosensitizing Agents; D003474:Curcumin
keywords: Curcumin-mediated photodynamic action; Inactivation; Oyster; Singlet oxygen