Optimizing of lipid production in Cryptococcus heimaeyensis through M32 array of Taguchi design

Critical problems such as high price of fossil fuel and climate change have stirred up growing interest in providing suitable alternatives such as biodiesel and ethanol, although these alternatives have presented us with problems as a result of global competition in human food supply. Environmental problems, depletion of fossil fuel and industrialization inevitably highlight the demand for substituting a viable and renewable energy resource. Accordingly, isolation of oleaginous yeasts and optimization of lipid production proves to be invaluable. A total of 67 yeasts, from which 9 were oleaginous yeasts, were isolated for the purpose of this study. After lipid extraction, the best strain was selected and then identified through PCR. Optimization was done using M32 design by Qualitek-4 (W32b) software for analyzing the experiments. The results showed that Cryptococcus heimaeyensis proved to comprise lipid, dry biomass and lipid productivity of 6.75 g L −1, 12.71 g L−1and 53.10% in optimized conditions. The extracted lipid was analyzed by FTIR spectroscopy and gas chromatography-mass spectrometry (GC-MS). The study revealed considerable potential of oleaginous yeasts as biodiesel feedstock and also the efficiency of Taguchi design in the optimization process.