Nutritional influences on biomass behaviour and metabolic products by Chlamydomonas reinhardtii

The recent works have shown the unicellular green alga Chlamydomonas reinhardtii is a relevant model for investigations of algal bioprocesses. In the current work, several media were evaluated in batch mode for a better understanding of C. reinhardtii metabolism. Nutrient-suppression using heterotrophic and mixotrophic conditions were performed. The findings showed C. reinhardtii metabolized lactose (from milk whey permeate)resulting in high biomass density (2.08 g/L)and total chlorophyll content (86.74 mg/m3). It was observed a specific growth rate of 0.023 h and 29 h for the doubling time. In sulfur-suppression, the algal growth (1.17 g/L)was reduced even though a carbon source (glucose)has been supplemented. Also, the specific growth rate (0.022 h)and the doubling time (31 h)was verified. The production of ethanol was slight and the acetic acid-suppression affected the C. reinhardtii performance providing slow cell growth (0.004 h)and high doubling time (154 h).