Carbohydrate, protein and lipid production of microalgae in a raceway pond system: use of fertilizer combinations of ZA-NaNO3 and SP36-K2HPO4as N and P nutrient source

Abstract

Microalgae is a photosyinthetic unicellular microbe which able to convert sunlight, water, carbon dioxide and nutrients to biomass. Since its biomass contains high grade of carbohydrate and lipid, microalgae is a potential source of biofuel. The objectives of this research were to identify 4 selected microalgae strains, to determine the optimum combination of technical grade ZA-NaNO 3 and SP36-K2HPO4 as the N and P nutrient source for cultivation of the strains at laboratory scale, and to evaluate the effects of the optimum combination of the N and P nutrient source on carbohydrate, protein and lipid production of each strain at field scale in a raceway pond system. The results showed that microalgae ICBB 9111 strain is Synechococcus sp., while ICBB 9112, ICBB 9113, and ICBB 9114 are Chlamydomonas sp. The highest carbohydrate was produced by Synechococcus sp. ICBB 9111 (43.90 % dry weight, DW) at 50 % ZA, 50 % NaNO3 and 100 % SP36, 0% K2HPO4 treatment. The highest protein was produced by Chlamydomonas sp. ICBB 9114 (29.09 % DW) at 50 % ZA, 50 % NaNO3 and 100 % SP36, 0 % K2HPO4 treatment. The highest lipid was produced by Chlamydomonas sp. ICBB 9113 (32 % DW) at 50 % ZA, 50% NaNO3 and 50 % SP36, 50% K2HPO4treatment.