An application of pulsed electric field for intracellular extraction from Chlorella vulgaris TISTR8580

This study aimed to apply Pulsed Electric Field (PEF) for Chlorella vulgaris TISTR8580 intracellular extraction.  Twenty-five g/L of algal cell samples were treated with PEF at 5 kV/cm under different pulses (1,500 2,500 3,500 and 4,500 pulses) with the initial temperature of 7 degree Celsius. Temperature, pH and conductivity were measured before and after treatments. Total carbohydrate and protein contents in the crude extracts were determined by the Phenol sulfuric acid method and the Bradford assay, respectively. Subsequently, carbohydrate composition was analyzed by Thin Layer Chromatography (TLC). In addition, the morphology of PEF-treated cells was observed under light microscope and cell survival was examined by re-culture in BG-11. The results showed an increased number of PEF pulses raised the temperature and conductivity of the algal extract. The highest total carbohydrate (23.19 ± 1.47 mg/L) and protein (144.48 ± 1.41 mg/L) contents were obtained from the crude extract treated with 2,500 pulses. TLC revealed that disaccharides and oligosaccharides were the major carbohydrate composition in the extract. PEF-treated algal cells exhibited color fading without any cell lysis. However, PEF treatment at 2,500 pulses led to cell death. This study clearly suggested that PEF is a potential technology for C. vulgaris TISTR8580 carbohydrate and protein extraction. Further optimization to enhance PEF extraction efficiency are still needed to achieve high yield of algal intracellular extract. Keywords : microalgae, Pulsed Electric Field, extraction