Division of Biology, Faculty of Science, University of Zagreb
Abstract
The proteolytic sulphide-producing bacteria (PSPB) are widely distributed in water and sediment and are a good indicator of the ecological status of ecosystems. From the ecological point of view it is important to distinguish the physiological group of PSPB from other bacteria producing H2S from sulphate, sulphite or thiosulphate. A new medium named peptone-cysteine-ammonium iron citrate agar (PCA) was developed and tested. The medium regularly gave a higher number of colony forming units than the control media for detection of sulphide formation, indole production and motility (Merck) and iron sulphite agar (Oxoid). For the enumeration of PSPB from the environment, the simultaneous incubation of samples in aerobic and anaerobic conditions is recommended and a higher number should be taken for interpretation
