OPTIMASI PRODUKSI BIOMASSA DAN LIPID MIKROALGA CHLORELLA VULGARIS MENGGUNAKAN TWO STAGE CULTIVATION METHOD DENGAN VARIASI KONSENTRASI SALINITAS

• Main Author: Gita Arumsari, Aluna
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/84635
• Institution: Institut Teknologi Bandung

Chlorella vulgaris is one of the microalgae species known for lipid production due to its high adaptability and growth rate. Research on microalgal lipids increased at the end of the 20th century, revealing that microalgal lipids can be used as an alternative raw material in various industrial sectors such as health, food, energy, and feed. The productivity of microalgal lipids depends on the cultivation conditions of the microalgae itself. Several studies have shown that inducing stress during microalgal cultivation can optimize lipid production, one of which is salinity stress. Salinity stress is known to cause osmotic and oxidative stress in microalgal cells, resulting in higher lipid accumulation (21.40% w/w - 56.42% w/w). Therefore, strategies to increase microalgal lipid production can be implemented with salinity stress through singlestage cultivation followed by nutritional stress in the second stage. This study began with a 10% v/v initial inoculum of Chlorella vulgaris with a cell density of 107 cells/mL cultured using 1 L culture bottles with a total culture volume of 800 mL. The cultivation conditions included an aeration rate of 1.5 vvm, a photoperiod of 16:8 hours (light), and an initial pH of 8.5. Two-stage cultivation started with salinity stress by adding various NaCl concentrations of 2.5% w/v, 5% w/v, and 7.5% w/v to the Nutri-Comp D and SP-36 fertilizer medium (0.72 g/L). The highest lipid fraction was 48.52 ± 0.29% w/w, the highest total lipid was 603.03 ± 0.004 mg/L, the highest biomass productivity was 56.49 ± mg/L, and the highest lipid productivity was 27.41 ± 0.0001 mg/L/day, obtained with a 2.5% NaCl concentration