European Journal of Biomedical and Pharmaceutical Sciences

ISOLATION, SCREENING AND CHARACTERIZATION OF CADMIUM TOLERANT BACTERIA FROM INDUSTRIAL EFFLUENT

Amritha G. Kulkarni, A.B. Vedamurthy*, Maheknaz K. Shaikh, Deepali T. Naik, Bhuvana Jadhav, Basanagouda M. Patil, Rashmi Pujar, Vidyashree Ilkal, Divya Rachagoudar

ABSTRACT

Soil and water contamination with cadmium (Cd) is a severe concern for the developing world due to its non
biodegradability and significant potential to damage th e ecosystem and associated services. Industries such as
mining, manufacturing, building, etc., rapidly produce a substantial amount of Cd, posing environmental risks.
Microremediation generally relies on the metabolic potential of microorganisms such as b acteria, fungi and algae,
that have been reported to have a high tolerance for metals. Bacteria are reported to have a significant
bioremediation capability in which hazardous pollutants act as a source of energy for cellular development and
growth. The pr esent study is therefor e aimed at isolation, screening and characterization of cadmium tolerant
bacterial strains from the effluent of West coast paper mill, Dandeli. Samples were collected asceptically and
subjected to elemental analysis to detect the presence of cadmium. Physi ochemical parameters, including
Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), CO 2 and Total Dissolved Solids (TDS),
were assessed. Four cadmium resistant bacterial strains (C1, C2, C3, and C4) were isolated, screened and
identified upto the genus level by cultural, microscopic and biochemical characteristics to assess their metal
tolerance potential. Among them, C2 strain exhibited significant cadmium tolerance and was subjected to
molecular characterization and identified as Klebsiella pneu moniae . Klebsiella pneumoniae was subjected to MIC
with various concentrations of cadmium (0.005, 0.010, 0.015, 0.020, 0.025, and 0.030 mg/mL) and was observed
that 0.025 mg/mL showed optimum growth which was explored for further analysis. Antibiotic susce ptibility test
revealed that Klebsiella pneumoniae was sensitive to cefixime and ciprofloxacin, indicating potential safety in
environmental applications. The results highlight the promising use of Klebsiella pneumoniae in the
bioremediation of cadmium con taminated aquatic environments.

Keywords: Cadmium tolerance, Klebsiella pneumonia , industrial