Studying culture media for improving growth of Green Algae, Botryococcus braunii

Microalgae are a potential resource for biofuel production based on their higher photosynthetic efficiency and production of triacylglycerol lipids. Botryococcuss braunii has the ability to accumulate a dry weight of 30-70% of hydrocarbons, making it a promising candidate for biofuel production. While B. braunii is an excellent candidate for biofuel, the slow growth rate of this particular species creates a barrier for its commercial development. The goal of this study was to determine the optimum concentration of nutrients for obtaining rapid growth of B. braunii. Cultures of B. braunii were initially grown on Chu No. 10 medium. Four different media types, Chu No. 13, BG-11, and Jaworski's (JM) media were compared with Chu No. 10 as a control. Media treatments were sterilized by autoclaving and 30 ml liquid medium was transferred to each 125 ml Erlenmeyer flasks. Algal cultures growing on Chu No. 10 medium were pelleted by centrifugation at 6000 rpm for 10 minutes. A pea sized pellet was then transferred to various media treatment in 125 ml flasks. There were three replicate flasks for each treatment. Flasks were placed under light (65 m. s-1.m-1) and 16 h photoperiod on a rotary shaker at 110 rpm. Changes in growth rates of algal cultures will be recorded at 3 and 6 week intervals using the packed cell volume (PCV) technique and optical density (OD). We hypothesize that significant differences will be observed in algal cultures grown on different media. Results will be determined at a future date.