Determination of sulphide produced by Desulfovibrio species of sulphate-reducing bacteria

Abstract

Orion, Model 94–16A, ion-selective electrodes have been used in indirect and direct modes for determining the sulphide produced by various Desulfovibrio species of sulphate-reducing bacteria, namely, D. desulfuricans, D. gigas and D. vulgaris. The sulphide determined by both modes matched the amounts expected from the nutrient sulphate present in the culture media and also matched the sulphide determined gravimetrically (lead sulphide) for the indirect mode.

All three species of bacteria also thrived on sulphite, thiosulphate and metabisulphite metabolic intermediates, but would not grow in the stable dithionate, or in the absence of inorganic sulphur species.

Indirect monitoring with the sulphide ion-selective electrode and with daily renewal of the trapping 1 M sodium hydroxide and 2% ascorbic acid solutions in the monitoring flask, permits the resolution of lag, growth and stationary and death phases of the various bacteria.