Microalgal biomass generation by phycoremediation of sewage water: an integrated approach for production of antioxidant and value added products

Abstract

Sewage water from an urban township in India has been used as a growth media for cultivation of a green alga Chlorella ellipsoidea in relation to phycoremediation and integrated approach for production of antioxidant and value added products. The concentration level of nitrate, phosphate, ammonia and total dissolved solid got significantly reduced in the sewage water media at post-stationary phase. An increased level of dissolved oxygen was observed on 30th day of incubation. The alga was efficient in the uptake of nutrients from sewage water. Most notably, complete removal of total dissolved solid was observed. Phaeopigment and physiological stress indices were virtually unaltered in most cases indicating facile adaptability. The stationary phase of the algal species was stable for 40 days as against only 22 days in BG11(N+) medium. Dry cell weight of the sewage water grown alga has been found to be about five times higher than that grown in BG11(N+) medium. The biomass accrued from sewage water as growth medium showed around 25% carbohydrate, 35% lipid and 56% protein and relatively higher amount of enzymatic and non-enzymatic antioxidants.