PRELIMINARY DESIGN OF LIPID PRODUCTION SYSTEM FROM CULTURED SPIROGYRA SP. ON ALGAL TURF SCRUBBER AND PRODUCTION OF OTHER BIOPRODUCTS BY APPLYING BIOREFINERY CONCEPT

• Main Author: Panigori Simanjuntak, Daniel
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/80457
• Institution: Institut Teknologi Bandung

Spirogyra sp. is a macroalgae that contains relatively high lipid content. In order to enhance lipid content, Spirogyra sp. was cultured under different concentration of nitrogen as nitrogen deficiency can enhance lipid production. The objective of this study was to determine the effect of nitrogen concentration to biomass growth and lipid accumulation on Spirogyra sp. with kinetic modelling approach. Spirogyra sp. was grown in modified Bold Basal Medium (BBM) for 8 days, with concentrations of nitrogen as much as 6.25 mg/L (control); 3.125 mg/L; 1.25 mg/L; and 0.625 mg/L; respectively. Results indicated that biomass accumulation on Spirogyra sp. that grown in nitrogen in sufficient amount was higher than that grown on nitrogen deficiency condition, with the highest biomass was 335.8 mg/L at 6.25 mg/L of N. Spirogyra sp. growth was modelled with logistic equation. Results indicated that the higher the nitrogen concentration, the lower the maximum specific growth rate (?max) value, and the higher the maximum biomass concentration (Xmax) value. Lipid yield on Spirogyra sp. that was grown in nitrogen sufficient condition was lower than that grown in nitrogen deficiency condition, with the highest lipid yield as much as 84.4 mg/g at 0.625 mg/L N. Lipid production was modelled with Luedeking-Piret equation, and the result indicated that the higher the nitrogen concentration, the lower the lipid formation coefficient (?) value, the higher the non-growth correlation coefficient (?) value. The obtained modeling parameters were used to estimate lipid productivity, and the highest lipid productivity obtained in this study was 16.92 mg g-1 day-1 at 0.625 mg/L nitrogen.