Microbiological and chemical properties of shungite water

. Abstract. Shungite is used in water filters that remove Escherichia coli from water. The mechanism and spectrum of the antibacterial activity of shungite are not precisely known. In this study, shungite and its dried water extract were characterized by means of X-ray diffraction, X-ray fluorescence and iodometry. The dried residue of the water extract of shungite was relatively poor in carbon (28.1% in the rock vs 0.5% in the residue), silica (23.9% in the rock vs 0.3% in the residue) and potassium (1.14% vs 0.05%), but rich in sulfur (1.6% vs 21.6%) and some metals, including iron (1.4% vs 10%), aluminum (2.1% vs 5%) and nickel (0.02% vs 1.14%). The survival of Escherichia coli , Pseudomonas aeruginosa , Staphylococcus aureus , Candida albicans , Streptococcus uberis and Saccharomyces cerevisiae in shungite water was measured. Escherichia coli , Pseudomonas aeruginosa and Streptococcus uberis did not survive for 24 hours in 3:7 shungite water extract, while Staphylococcus aureus , Candida albicans and Saccharomyces cerevisiae survived as well as in distilled water. Neutralization of pH did not abolish the bactericidal effect. However, in the presence of nutrients, shungite water did not show bacteriostatic or bactericidal effects.