Distribution of bacteria in the mineral waters of the Polish Lowlands

The paper presents the results of research into the distribution of microorganisms in brines with the total dissolved solids of 40–80 g/dm3, found in the Paleozoic platform of the Polish Lowlands. Water samples were collected from boreholes extracting water from the Jurassic and Triassic aquifers. The total number of microorganisms in the examined water samples ranged from 10 to 30 x 103 cells per 1 cm3, while their viability ranged from 14 to 58%. The samples contained heterotrophic, chemoautotrophic, aerobic and anaerobic bacteria as well as bacteria participating in the transformation of iron and sulphur compounds. Molecular identification of culturable bacteria isolated from water samples revealed that they belong to six genera: Bacillus and Staphylococcus within phylum Firmicutes, Micrococcus and Kocuria within phylum Actinobacteria, and Marinobacter and Pseudoalteromonas within phylum Proteobacteria (class Gammaproteobacteria). The most abundant were Bacillus and Micrococcus isolates related to six different species: B. amyloliquefaciens, B. pumilus, B. methylotrophicus, B. licheniformis, M. luteus and M. yunnanensis.