EFFECTS OF DIFFERENT NITROGEN AND PHOSPHORUS NUTRIENTS AND STRESS CONDITIONS ON THE GROWTH AND LIPID ACCUMULATION OF THE MICROALGA PICOCHLORUM SP.

Abstract

Picochlorum sp. microalgae is able to accumulate large amount of lipid content in cells which are potential for biofuel production, function food and pharmaceutical applications. Picochlorum sp. reached the highest cell density after 6 days of culture under the nitrogen (NO₃^-) and phosphorus (H₂PO₄^-) supplemented MD4 medium. Lipid accumulation of Picochlorum sp. in MD4 medium supplemented with nitrogen (NO₃^-) and phosphorus (H₂PO₄^-) was lower than that of Picochlorum sp. in a separate medium of either nitrogen or phosphorus. The MD4 medium containing 0.1-0.15 g/L of NPK fertilizer stimulated growth of Picochlorum sp. Under stress conditions, the growth of Picochlorum sp. decreased; however, lipid content increased under the combination of 1.0 M salinity and NPK starved conditions.