Oil cake extract as low-cost alternative media for increasing lipid and biomass productivity in Scenedesmus quadricauda for biofuel applications

In tropical countries, the oil mill industry releases a large amount of wastage. From this wastage, extracts can serve as an economical nutrient source or substrate that can support the cultivation of microalgae. This study is aimed to employ green microalgae, Scenedesmus quadricauda potentially existing in the oil mill industrial wastage for digestion. Because of the existence of bioactive substances with advantageous qualities in producing high lipids from microalgae as a biofuel substrate, oil mill cake extract was chosen as the primary source of nutrients. This study accentuated the effectiveness of oil mill cake wastage extract as the main carbon source to maintain the growth of microalgae and simultaneously increase the lipid content. This study determined the total lipid, protein, carbohydrate, and chlorophyll content of Scenedesmus quadricauda . High lipid biomass was discovered utilizing the Nile red lipid detection technique after the conditions were optimized. To quantify the lipids produced by this microalgae, thin layer chromatography (TLC) and gas chromatography (GC-FID) were used. The oil cake extract was found to be an alternative and cost-effective medium of the Scenedesmus quadricauda, which is more suitable in the lipid yield and biomass productivity for biofuel application. The biomass content of S. quadricauda in groundnut oil cake was 80% higher than the control (331 mg/L) which is 0.79-fold higher. On the 20th day, the maximum total protein and carbohydrate contents were 330 and 96 mg/L, respectively, among the varied concentrations of coconut oil cake extract tested. This implies that the Scenedesmus quadricauda grown using coconut oil cake extract can be suitable for biofuel production.