The effects of UV-C and HNO2 mutagen, pH and the use of commercial fertilizers on the growth of microalgae Botryococcus braunii

Botryococcus braunii microalgae is a potential producer of biodiesel as an alternative fossil fuel because it has a high lipid content. This paper was conducted to determine the optimal mutation agent, microalgae resistance to changes in pH and, optimal nutrients from commercial fertilizers for the growth of Botryococcus Braunii . To find the best mutation agent, culture was planted in seawater media with Walne nutrient with UV-C and HNO 2 exposure. The results showed that the optimal mutation agent was a mutation with UV-C exposure expressed by lipid productivity values. Furthermore, to see microalgae resistance to changes in pH, B. braunii was cultured in seawater media with Walne nutrients at various pHs, namely 3-8 with mutations of UV-C rays and without mutation agents. The results show that natural and mutated B. braunii microalgae grow optimally at pH 8. This also shows that mutated microalgae have better adaptability compared to natural microalgae, as evidenced by the number of natural microalgae cells that continues to decrease with a decrease in pH. The final goal is to find the optimal nutrient for growth in B. Braunii from commercial fertilizer. Culture was planted in seawater media with various concentrations of commercial fertilizer, for 7 days of culture, the results showed that each nitrogen source had a different effect on the growth of microalgae