COST EFFECTIVE CULTIVATION AND BIOMASS PRODUCTION OF GREEN MICROALGA DESMODESMUS SUBSPICATUS MB. 23 IN NPK FERTILIZER MEDIUM

Abstract

Microalgal biomass has emerged as a promising alternative to replace plant-based biofuel feedstock due to its higher lipid productivity. But cultivation of microalgae in expensive analytical grade culture media is a major obstacle in feasible algal biofuel production. Hence the present investigation was carried out to find an alternative, low-cost culture medium for the increased biomass yield and biochemical production of microalga, Desmodesmus subspicatus MB. 23. The strain was cultivated in different concentrations of 19: 19: 19 NPK media and checked for the algal biomass production and biochemical accumulation. Maximum algal cell density (5290 ×104 cells/ ml), biomass yield and productivity (2.72 g/L, 60.87 mg/L/d) was attained in 2 g/ L NPK fertilizer medium, whereas 1g/L medium exhibited increased chlorophyll production (chl-a, 4.7 mg/g d wt, chl-b 1.7 mg/g d wt). High level of carotenoid accumulation (4.6 mg/g d wt) as well as lipid accumulation (29.5%) was found in 0.5g/L fertilizer media and Fatty acid methyl ester analysis of the strain showed abundant production of C16 and C18 fatty acids. Findings of the current study proved that, lower concentration of 19:19:19 NPK fertilizer can be used for the enhanced production of green microalgae. Other than cost effective biofuel production, NPK fertilizer grown D. subspicatus can also be used for the production of a wide range of metabolites such as food and feed additives, pharmaceuticals and cosmetics.