Contribution of specific impurities in crude glycerol towards improved lipid production by Rhodosporidium toruloides ATCC 10788

The use of crude glycerol doubled the biomass and tripled the lipid concentration obtained using Rhodosporidium toruloides ATCC 10788, compared to pure glycerol. Methanol in crude glycerol severely affected the biomass and lipid obtained from this strain. However, it was tolerant to salt levels of 1.5% (w/v) in the media. Soap and FAME present in crude glycerol had a positive influence on biomass and lipid production. This strain also has the unique capacity to consume soap as a carbon source. While growing on 3.5% (w/v) of soap as the sole carbon substrate, 12.87 g/L of biomass and 5.40 g/L of lipid were obtained at the end of 168 h. This study also helped us ascertain the reason for such a large improvement in biomass and lipid when crude glycerol containing large quantities of soap (32.97 wt%) was used.