Growth and biochemical composition of filamentous microalgae Tribonema sp. as potential biofuel feedstock

Filamentous oleaginous microalgae Tribonema minus have advantages in relatively easy harvesting and grazers resistance in mass cultivation due to its filaments in previous study. To evaluate whether the genus Tribonema is a valuable candidate for use in biofuel production, the morphology, growth, biochemical composition and fatty acid profile of six filamentous microalgae strains Tribonema sp. were investigated. All the strains are unbranched filament in single row of elongated cylinder, attaining 0.5-3 mm in length. The growth rates of tested strains were 0.35-0.42 g L(-1) d(-1). Generally, for all strains, decrease in protein content was followed by a slight increase in lipid and significant increase in carbohydrate in early phase, afterwards, lipid increased constantly inversely to decrease in carbohydrate content. After 15-day cultivation, total lipid contents of tested strains ranged from 38-61 %, of which TAG were the majority and palmitic acid (C16:0) and palmitoleic acid (C16:1) were the dominant components. The study confirmed that the genus Tribonema is the potential for biodiesel and bioethanol production upon culture time.