Detection results of lead resistant bacteria from soil and water in Ulaanbaatar city / Эрүүл мэндийн лаборатори

ABSTRACT

Background@#Soil pollution in Ulaanbaatar has increased in recent years, causing infectious and non-communicable diseases, both benign and malignant. </br> Therefore, in order to reduce soil pollution, it is necessary to isolate strains resistant to heavy metals and use these microorganisms capable to degrade or accumulate heavy metals for bioremediation purposes.@*Methods@#Bacterial pure cultures were isolated from soil and water samples and incubated in a Nutrient Broth medium with a lead concentration of 1000 mg/L in a thermostat with a shaker at 37°C. The growth rate was determined at a wavelength of 600 nm using a Spectrophotometer.@*Results@#In total 69 pure cultures were isolated from the soil samples and 65 pure cultures from them were able to grow at the concentration of lead of 1 mmol/L. 4 pure cultures (UBLF1, UBLF3, UBMF2, and SUBZ4) were able tolerate lead concentrations up to 8 mM. These cultures were determined by semi-automatic VITEK®2 analyzers and identified as Bacillus sp. (83%) and UBMF2 identified as Bacillus thuringiensis (93%) respectively.@*Conclusion@#The lead content in water samples were found to be acceptable, and isolated pure cultures were not able to withstand the lead concentrations.</br> Pure culture UBLF3 isolated from the soil capable to reduce lead concentration (500 mg/L) up to 302 mg/L and 230 mg/L in the medium, and pure culture UBMF2 up to 340 mg/L and 279 mg/L respectively