Investigation Into The Growth Phase Dependent Sensitivity Of Mycobacterium Aurum To Chlorine And Quantification Of Reactive Oxygen Species

Abstract Chlorination is one of the best known disinfectant methods for treating drinking water. Mycobacterium aurum and Escherichia coli are common waterborne organisms and as mycobacterial species are much resistant to reactive oxygen species the initial effect H2O2 and HOCl was quantified in Escherichia coli and Mycobacterium aurum with the concentrations ranging from 0 to 0.16mM.The influence of reactive oxygen radicals with all the three growth phases like early log 3rd day in M.aurum and 3rd hour in E.coli mid log 9th day and 9th hour and early stationary phase 12th day and 12th hour was checked and a correlation between the intracellular superoxide and hydroxyl with normalized change in CFU was expressed. The organisms susceptibility to H2O2 and HOCl was observed to be dependent on its growth phase. The possible reasons for their difference in resistance were analysed.