The Effect of Potassium Phosphate in Static Culture of Scenedesmus dimorphus

Scenedesmus dimorphus is a green microalga which can grow rapidly in wastewater and contains of lipid 16-40% on dry matter which makes it to be one of the most viable source of third generation biofuels feedstock. In this study, two types of water sample were collected and modified. The water was filtered to be modified with adding of amendment materials which isdipotassium phosphate (K2HPO4). The two different types of modified water which are Modified Tap Water (MTW) and Modified Sea Water (MSW) were used as the medium to conduct static culture of Scenedesmus dimorphus. Filtered Tap Water (FTW) and Filtered Sea Water (FSW) were used as negative control. While the proteose medium being the best medium for the growth of Scenedesmus dimorphus as reported in the literature was used as positive control to compare the effectiveness of modified water as a culture medium. The cultures were analysed for cell biomass by dry cell weight (DCW) and OD. The cultures were carried out during 2-3 weeks and samples were withdrawn every four days for analysis. The lipid was extracted by using enzymatic hydrolysis after cultivation days done. The highest lipid content obtained after weeks of cultivation observed was the FTW medium with 31% while in proteose medium and FSW with 17% and 28.5% respectively. Study on the effect of potassium phosphate on the biomass content of Scenedesmus dimorphus achieve with the highest cell productivity of 7g/L after 18 days of cultivation in MSW and 4g/L MTW. The products were then being process to produce lipid by using chemical extraction. This indicates that the best cultivation medium is FTW with the highest lipid content without addition of amendment materials