Research Scholar, Deparment of Biotechnology, IIT Guwahati. 2009-ongoing
Water is referred to be polluted whenit is rendered unfit for human use as drinking water or it becomes unfit for supporting the aquatic biotic communities as fishes. Water pollution is a major global problem and has been suggested as the leading worldwide cause of deaths and diseases. Water pollution are mainly due to anthropogenic contaminants which may be organic (e.g. Detergents, herbicides, petroleum hydrocarbons, industrial solvents e.t.c.), inorganic (heavy metals, nitrates, phosphates) and macroscopic (e.g. plastics, paper, food wastes). Phenol is a hazardous organic pollutant that is released in wastewaters of industrial processes of petrochemical, textile, coal processing, paint, plastic industries e.t.c. Due to toxic effects of phenol on aquatic organisms, human beings as well as microorganisms it is utmost necessary to remove phenol from industrial wastewater to the emission standards set by environmental protection agencies. Phenol is reported to be biodegraded by bacteria, fungi as well as microalgae. The phenol biodegradation capabilities of bacteria and fungi have been well elucidated, whereas the role of microalgae in biodegradation of organic pollutants as phenol has been much less studied. Microalgae is predominantly found in all aquatic ecosystems and it is the most important primary producer in the aquatic ecosystem. Thus understanding the role of algae in biodegradation generates interest. Other attractive feature leading to interest in studying the biodegradation capabilities of microalgae include cost effective nature of the process as it does not need supply of additional carbon source to maintain biomass growth during the biodegradation process. It can grow phototrophically utilizing environmental CO2 as carbon source. Microalgae while degrading organic pollutants can concomitantly remove ammonium nitrate and phosphate the major contributor to eutrophication in water bodies. Microalgae produces oxygen photosynthetically so it can eliminate the necessity of mechanical aeration in bioreactors which is costly and is limited by poor aqueous solubility of oxygen as well as chances of volatilization of toxic organic compounds during mechanical aeration. The conventional wastewater treatment plants are major contributor to green house gases. Algae based wastewater treatment also releases CO2 but algae consumes more CO2 while growing than that is being released by the plant. This makes the entire system carbon negative.
My research focuses on elucidating the phenol degradation capability of microalgae and to understand the enzymatic mechanism involved in phenol degradation in microalgae. My research work also focuses on isolation, purification, characterization and over expression of the phenol metabolizing enzyme from microalgae.