title: Intracellular mechanisms of solar water disinfection.
abstract: Solar water disinfection (SODIS) is a zero-cost intervention measure to disinfect drinking water in areas of poor access to improved water sources, used by more than 6 million people in the world. The bactericidal action of solar radiation in water has been widely proven, nevertheless the causes for this remain still unclear. Scientific literature points out that generation of reactive oxygen species (ROS) inside microorganisms promoted by solar light absorption is the main reason. For the first time, this work reports on the experimental measurement of accumulated intracellular ROS in E. coli during solar irradiation. For this experimental achievement, a modified protocol based on the fluorescent probe dichlorodihydrofluorescein diacetate (DCFH-DA), widely used for oxidative stress in eukaryotic cells, has been tested and validated for E. coli. Our results demonstrate that ROS and their accumulated oxidative damages at intracellular level are key in solar water disinfection.
authors.affiliation: Plataforma Solar de Almería - CIEMAT, P.O. Box 22, 04200 Tabernas (Almería), Spain.|CIESOL, Joint Centre of the University of Almería-CIEMAT, 04120 Almería, Spain.
authors.forename: María
authors.initials: M
authors.lastname: Castro-Alférez
authors.affiliation: Plataforma Solar de Almería - CIEMAT, P.O. Box 22, 04200 Tabernas (Almería), Spain.|CIESOL, Joint Centre of the University of Almería-CIEMAT, 04120 Almería, Spain.
authors.forename: María Inmaculada
authors.initials: MI
authors.lastname: Polo-López
authors.affiliation: Plataforma Solar de Almería - CIEMAT, P.O. Box 22, 04200 Tabernas (Almería), Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Fernández-Ibáñez
mesh_terms: D004203:Disinfection / Q000379:methods*; D048168:Escherichia coli K12 / Q000378:metabolism / Q000528:radiation effects; D005452:Fluoresceins; D005456:Fluorescent Dyes; D006801:Humans; D017382:Reactive Oxygen Species / Q000378:metabolism; D012993:Solar Energy; D013472:Sunlight; D014871:Water Microbiology; D018508:Water Purification / Q000379:methods*; D014881:Water Supply
chemical_list: D005452:Fluoresceins; D005456:Fluorescent Dyes; D017382:Reactive Oxygen Species; C029569:diacetyldichlorofluorescein