Ranjitha Jambulingam
Using the Nile red staining method, fifteen colonies of microalgae were recovered from agro-industrial waste water and evaluated for their high lipid content. Based on the findings, three green microalgal species with significant lipid content were identified as Chlorococcum sphacosum, Chlorella vulgaris, and Volvox carteri, which will be studied further. The selected three green microalgal strains were cultured in two different cultivation methods (Mixotrophic and Heterotrophic) to enhance the biomass and lipid production. In mixotrophic cultivation method, Chlorococcum sphacosum showed significant increase in the total lipid content (81%) and biomass concentration (810 mg L-1) were grown in 10g L-1 of sugar molasses than in heterotrophic condition. Chlorococcum sphacosum was cultured in modified BBM media, high biomass and lipid content were achieved and compared with BBM media. Among the three microalgal species, the lipid content was high in Chlorococcum sphacosum (81.6%) and further used for the production of biodiesel. Chlorococcum sphacosum was cultured in both sewage water (SW) and treated effluent water from septic tank (TEW). The physiochemical parameters of SW and TEW were quantified before and after culturing of Chlorococcum sphacosum. It was found that all the physiochemical parameters were found to be reduced after culturing the microalgae which indicates that Chlorococcum sphacosum can be used for the treatment of wastewaters.