DNA-protection and antioxidant properties of fermentates from Bacillus amyloliquefaciens B-1895 and Bacillus subtilis KATMIRA1933.

UNLABELLED: DNA protective and antioxidant activity of Bacillus amyloliquefaciens B-1895 and Bacillus subtilis KATMIRA1933 were evaluated by Escherichia coli-based Lux biosensors. Two biosensor strains of E. coli, MG1655 (pColD-lux) and MG1655 (pSoxS-lux), which react on DNA damage and superoxide-anion radical activity, were used. SOS-response and Sox-response were stimulated by addition of dioxidine (2,3-Quinoxalinedimethanol,1,4-dioxide) and paraquat (N,N'-dimethyl-4,4'-bipyridinium dichloride) respectively. Preparations of both Bacillus fermentates demonstrated DNA protective and antioxidant (superoxide scavenging) activity (up to 60·19%). The strain К1933 is, in general, characterized by higher DNA protective activity (28·85%), with parameters of antioxidant activity of both bacilli strains being statistically not significantly different. Sporogenous potential probiotic micro-organisms with antioxidant and DNA protective activities can become an effective tool for compensation of various negative oxidative stress processes in humans. SIGNIFICANCE AND IMPACT OF THE STUDY: In humans, oxidative stress is a cause or an important component of many serious diseases, as well as being one of the age influencing factors. Environmental stresses lead to the increase in levels of reactive oxygen species (ROS). Oxidative DNA damage is a side effect of nonspecific inflammation. These human health challenging factors trigger the search for health-promoting bacteria capable of production of antioxidants and DNA-protectors. In this study, two Bacillus strains of interest were shown to produce noticeable DNA protective and antioxidant activities.