ISOLATION OF LIPID FROM TROPICAL MARINE MICROALGAE NANNOCHLOROPSIS OCEANICA GSI IN EXPONENTIAL AND STATIONARY GROWTH PHASES

• Main Author: Sofianti, Pradina
• Format: Final Project
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/51973
• Institution: Institut Teknologi Bandung

The level of world energy consumption is expected to increase while the supply of raw materials for fossil energy is running low, so it is necessary to seek renewable energy sources. Several studies have reported that microalgae have a high lipid content and can be an alternative source for biodiesel production. One of the microalgae that has been reported to have a high lipid content is the Nannochloropsis oceanica. Previous research has been carried out on the analysis RNA content of N. oceanica GSI to determine gene expression in the exponential and stationary growth phases. To show that there is the regulation of lipid biosynthesis by gene expression, it is necessary to check the lipid content. The objective of this study is to analyze the total lipid content and fatty acid composition of N. oceanica GSI in the exponential and stationary growth phases. The method used in this study is to first cultivate microalgae cells which are then harvested in the exponential and stationary growth phases. Secondly, isolation of lipid from microalgae cells. The lipids of microalgae are then hydrolyzed, and the fatty acids obtained are converted through a transesterification reaction into biodiesel in the form of fatty acid methyl-esters (FAME). Fatty acids in the form of FAME have been characterized by GC-MS. The results have shown that the fraction of cell biomass harvested in the stationary phase is greater than the exponential phase, namely 1.9 for wet biomass and 2 for dry biomass. The total lipid content per weight of dry biomass in the stationary phase was higher than that in the exponential phase with the ratio of about 8: 7, namely 81.27% and 71.88%. The hydrolysis and transesterification of fatty acids have been carried out on 37.2 mg of lipids from the exponential phase and 7 mL FAME has been produced.