Effect of antioxidant protection against ultraviolet radiation and antibiotic susceptibility of Escherichia coli

Abstract

Antioxidants possess both biological and physiological properties for preventing damage to cells induced by ultraviolet radiation. The  study was conducted to observe the effect of some antioxidants on the survival rate of non-pathogenic and pathogenic strains of  Escherichia coli. Solutions of Vitamin A, Vitamin C, and Vitamin E were incorporated into sterile Petri dishes containing a fixed amount of  the inoculums, the population of the bacterium was determined, and then exposed to ultraviolet light at varying degrees of time. After  exposure, Vitamin A reduced cell number at every exposure time, with the highest reduction observed after 20 minutes of exposure time,  from 68 cfu/ml to 57 cfu/ml for clinical E. coli (E1), while environmental E. coli (E2) isolate cell reduction was 41 cfu/ml at 20 minutes  observed at concentrations 100 mg/100 ml. For vitamin C at a concentration 100 mg/100 ml, E1 reduced to 8 cfu/ml at 20 minutes. At  100mg/100ml, Vitamin E reduced E2 colonies to 11 cfu/ml at 20 minutes. The antibiotic susceptibility of the isolates showed that E1  showed resistance to 62.5% of the antibiotics tested against, while E2 was resistant to 50% of the antibiotics. This study revealed that at  higher antioxidant concentrations, bacterial cells tend to be protected against the effects of UV radiation at a shorter exposure time.