Mass culture of Botryococcus braunii Kutz. under open raceway pond for biofuel production

Three different strains of colonial green alga Botryococcus bruanii Kutz. AP103, AP104 and AP105 were isolated from the freshwater lake Kolleru, Andhra Pradesh, India. The morphological features of these three isolates were studied under laboratory conditions. Molecular identification of the strains was carried out using 18S rRNA analysis and their systematic position was confirmed to species level as B. braunii. Among these isolates, B. braunii AP103 recorded highest biomass concentration of 1.7 ± 0.12 g L−1, 17% lipids, 17% proteins, 32% carbohydrates and 13% hydrocarbons under laboratory condition. Under open raceway pond AP103 produced a biomass concentration of 1.8 ± 0.13 g L−1, 19% lipids, 33% carbohydrates, 18% proteins and 11% hydrocarbons. The hydrocarbons profile showed the presence of heptadecane (34%) and hexadecane (12.5%). Oleic (25.7%), linolenic (34.26%) and palmitic (9.42%) acids were the major fatty acids present in the lipids extracted from AP103.