The potential of electron transport system (ETS) activity measurement
method with regard to two anaerobic bacteria namely Desulfovibrio desu
lfuricans and Desulfovibrio vulgaris was studied. Both the species red
uced 2-(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyl tetrazolium chloride
(INT) to INT formazon. Laboratory experiments indicated that 20 minute
s treatment of INT was adequate to give optimum ETS values. The study
showed that ETS activity varied from species to species and age of the
culture. ETS activity was found to be varying in media with different
composition.