RT journal article
T1 Inactivation efficacy and reactivation of fecal bacteria with a flow-through LED ultraviolet reactor: Intraspecific response prevails over interspecific differences
A1 Romero Martínez, Leonardo
A1 Duque-Sarago, Paola
A1 González-Martín, Claudia
A1 Moreno Andrés, Javier
A1 Acevedo Merino, Asunción
A1 Nebot Sanz, Enrique
A2 Tecnologías del Medio Ambiente
K1 Water disinfection
K1 Ultraviolet inactivation
K1 Light emitting diodes (LEDs)
K1 Photoreactivation
K1 Fecal bacteria
AB Treatment with ultraviolet (UV) light is a common option for inactivating waterborne organisms. The mercury vapor lamps conventionally used as a source of UV-C light for water disinfection are eventually replaced by light emitter diodes (LEDs) in the middle term due to their higher efficiency and lack of hazardous materials. Nonetheless, biological mechanisms for repairing UV damage caused by the UV treatment are some of its significant undesirable features. The objective of this study is to evaluate and compare the UV-resistance and the reactivation degree in different strains of E. coli and E. faecalis treated with a flow-through reactor equipped with LEDs with an emission range between 265 and 285 nm. The treated organisms were subjected to various illumination regimes after the UV irradiation. The results obtained indicated that intraspecific differences between the strains of E. coli were greater than the interspecific differences with respect to E. faecalis in terms of UV-resistance and repairing potential. The UV doses necessary to achieve four log-reductions ranged from 10.2 to 16.3 mJ cm−2 for E. coli and from 11.1 to 11.4 for mJ cm−2 for E. faecalis. Dark repair was not observed within 24 h after the UV irradiation whereas the degree of photorepair depended on both the bacteria strain and the applied UV dose. The exposure of the irradiated organisms to an illuminated environment entailed and increasing between the 18 % and the 160 % of the UV dose required to achieve four log-reductions. © 2023 The Author(s)
PB ELSEVIER
SN 2214-7144
YR 2023
FD 2023-04
LK http://hdl.handle.net/10498/27946
UL http://hdl.handle.net/10498/27946
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 06-nov-2026