PERTANIKA JOURNAL OF SCIENCE AND TECHNOLOGY

The feasibility study on Chlorella sp. lipid extraction using an electrolysis treatment (ET) as pre-treatment was investigated. Stainless steel was used as the anode and cathode material. The ET method was conducted in a batch or continuous system with or without air aeration and recycling flow. The total lipid in Chlorella sp. A_WET and A_WET were not analysed due to small sample volume. Approximately same amount of lipids were attained from Chlorella sp. B_WOET (7.97 ± 0.43% g_lipid/g_{dry wt}) and B_WET (7.95 ± 0.37% g_lipid/g_{dry wt}) if treated at 5 V/cm and aerated at 16.7 µm³/s for 1800s. Whereas, if Chlorella sp. was treated at 13 V/cm and aerated at 16.7 µm³/s for 1800 s, the total lipid obtained in Chlorella sp. C_WOET (8.18 ± 0.49% g_lipid/g_{dry wt}) was 1.13-fold higher than C_WET (7.22 ± 0.47% g_lipid/g_{dry wt}). Meanwhile under semi-continuous system, similar pattern of result was achieved in Chlorella sp. D_WOET (8.58 ± 0.49% g_lipid/g_{dry wt}) with 1.11-fold higher than DWET (7.72 ± 0.54% g_lipid/g_{dry wt}), if treated at 14 V/cm and recycled at 2.3 µm³/s for 3000s. This corresponded to lipid oxidation that might have occurred during the ET method. The fatty acid methyl ester (FAME) composition of Chlorella sp. D_WOET and D_WET contained predominantly methyl linolenate (C18:3) and methyl palmitate (C16:0). The concentrations of methyl palmitate attained in Chlorella sp. D_WOET and D_WET were 0.049 ± 0.005 g/m³ and 0.045 ± 0.005 g/m³, respectively.