Effects of temperature and its combination with high light intensity on lipid production of Monoraphidium dybowskii Y2 from semi-arid desert areas

Temperature and light intensity are important environmental factors influencing microalgae for biodiesel production. The aim of present work was to study the effects of temperature (15 degrees C, 25 degrees C, and 35 degrees C) and its combination with high light intensity (HL, 400 mu mol photon m(-2) s(-1)) on lipid production of Monoraphidium dybowskii Y2 which was isolated from desert. The results demonstrated that algal growth was only inhibited at 15 degrees C. Promoted lipid content and decreased Fv/Fm were observed in 15 degrees C and 35 degrees C. Cellular carbohydrate, protein conversion and membrane lipid (MGDG, DGDG and SQDG) remodeling contributes for lipid accumulation. Stress combined temperatures with HL are benefit for lipid production, especially desired neutral lipid productivity all exceed 40 mg L-1 d(-1). Fatty acids compositions of C16:0 and C18:1 were further promoted under 15 degrees C or 35 degrees C combined with HL. Thus, M. dybowskii Y2 will well-adapted to outdoors cultivation for biodiesel production.