Efficacy of chemical factors on production and extraction of biodiesel by microalgae

Abstract

Environmental concerning factors responsible for carbon dioxide emissions and depletion of petroleum based fuel are the driving factors for the search of alternative fuels like biodiesel. The growth of microalgal cells and their metabolic activity toward lipid production could be controlled by the nutrient factors employed in production media. The lipid accumulation ability of the microalgal strains could be influenced by the deprivation of vital chemicals like carbon, nitrogen, calcium and magnesium. In the part of commercializing microalgal based biodiesel, cost effective measures in oil extraction and downstream processes have to be considered. Huge varieties of microalgal cellular pretreatment methods are employed to enhance cellular disintegration so as to facilitate oil extraction by structural modification of carbohydrates present in cell wall. The diversified methods used for microalgal pretreatment encompass chemical, thermal, biological, mechanical or combinatorial approaches. Among all the pretreatment methods chemical methods are greatly advantageous while concerning the feasibility in energy and time consumption. Combinatorial approaches like thermochemical pretreatment or microwave assisted extraction methods are very successful in terms of feasible energy production under limited time consumption. Above all, genetic engineered microbes which could be able to withstand suitable pretreatment methods were developed. This present review tried to explore the activity of chemical parameters and also delineate the nutrient deprivation factors involving in the cellular metabolism of microalgal biomass for lipid production.