A Study on the Potential of Moringa Leaf and Bark Extract in Bioremediation of Heavy Metals from Water Collected from Various Lakes in Bangalore

Many industrial water bodies are polluted with organic and inorganic contaminants discharged into them as effluents. Bioremediation is a waste water management technique that facilitates removal or neutralization of pollutants from a contaminated site. Many plants and their extracts have been used for bioremediation of heavy metals in the process of phytoremediation. Moringa olifera, also known as drumstick is a fast growing, drought resistant plant that belongs to the family of Moringaceae. Its fruit and leaf are consumed as diet and the bark has healing properties as recorded in ancient medicine. Moringa olifera seeds have been reported to have bioremedial property which can be enhanced on chemical modification. Data optimization studies have been performed for various heavy metals and their adsorption on to the chemically modified biosorbent. Our study aims at identifying major polluted lakes in and around Urban Bangalore and their phytoremediation using dried and chemically modified leaf and bark powders. Contaminated water samples were collected from Bellandur, Varthur and Hebbal lakes and were subjected to biosorption by the modified leaf and bark powders according to the parameters optimized for seed powders. The reduction in heavy metal content was observed by Thin Layer Chromatography (TLC) and Atomic Absorption Spectroscopy (AAS) methods. Other physico chemical parameters like turbidity, BOD, COD, DO, Nitrate and Phosphate content were examined to emphasize the bioremedial property of chemically modified Moringa olifera leaf and bark extracts. Biosorption of heavy metals was found for the bark and leaf treated water samples and also reduction in the BOD, COD, nitrate and phosphate content and turbidity were observed for both the biosorbents. These results showed the enhancement of potability of these treated water samples and their applications in a larger scale. Further recovery and reusability of the biosorbents for enhanced recovery of the pollutants has to be studied for their commercialization.