Photosynthetic Microorganisms Consortium as Bioindicators for Heavy Metals

Heavy metals that are discharged through industrial and agricultural activities cause contamination, especially to the water sources, and bring about negative impacts on the flora and fauna in the ecosystem. The monitoring of heavy metals in the environment requires high technical skills with sophisticated equipment and is also time-consuming. In this study, the potential of using natural photosynthetic microorganism consortiums collected from natural water bodies as bioindicators for the screening of heavy metals was explored. The photosynthetic microorganism consortiums were first cultured in lab, immobilized, and then exposed to different heavy metals (Cd, Cu, Ni and Co) at different concentrations (0.01 mg.L-1, 0.05 mg.L-1, 0.10 mg.L-1, 0.50 mg.L-1, 1.00 mg.L-1 and 5.00 mg.L-1). The fluorometric responses before and after the exposure to heavy metals were measured. The results revealed that consortium cells responded to a wide range of heavy metals within a short period of exposure. The responses showed that the consortium cells can detect the presence of Cd, Cu, Ni, and Co within the range of 0.05-5.00 mg.L-1. The study confirmed that the photosynthetic microorganism consortiums collected from natural water bodies could be used as bioindicators for the screening of heavy metals.