Hydrogen sulfide production by Desulfovibrio and Desulfotomaculum SPP. grown on glucose, lactate and succinate

Two strains of Desulfovibrio spp., and two strains of Desulfotomaculum spp., as well as a mixture of these four were cultivated in-a basal medium containing as carbon source either lactate, succinate or glucose. Hydrogen sulfide was assayed by an iodometric titration every second day during a period of 3 weeks. Results showed lactate to be the most suitable carbon source, and 30 mg/l to be the maximum H₂S-S produced during 20 days of incubation. Desulfotomaculum spp. were more metabolically active than Desulfovibrio Spp.. In the mixed culture grown on glucose, synergism occurred increasing H₂S production over levels yielded by individual strains. Competition for substrate in mixed cultures grown on succinate and glucose reduced H₂S levels to an average value produced by individual strains.