Efeito da luz solar sobre a sobrevivência de Escherichia coli, em areia de praia

Abstract

This research work was aimed at appraising the survival of a Escherichia coli’s strain as resistant to the nalidixic acid, through inoculation into sand samples exposed to sun light. The experimental layout was designed in six microcosmos, namely: (a) working experiment – sterilized sand plus sterile saline plus E. coli; (b) control experiment – non-sterilized sand plus sterile saline plus E. coli; (c) blank control – sterilized sand + sterile saline, with three of them being exposed to sun light and three kept in the dark, protected against sun light’s influence. Considering the experimental microcosmos and after a 48-hour period of sun light exposition had elapsed, no E. coli strain was recovered what bears out the fact that the ultraviolet irradiation is lethal to a viable cell. The samples from inoculated sand were not found to be favorable to the growth of E. coli cultivation broth when exposed to sun light.