Produção de Single Cell Protein (SCP) por leveduras utilizando o glicerol bruto como fonte de carbono

Abstract

Crude glycerol, generated at the rate of 10% (v/v) during biodiesel production, can be used by microorganisms for their bioconversion in several industrial products, such as biomass or Single Cell Protein (SCP). The objective of this work was to evaluate the production of yeast SCP using crude glycerol as a carbon source, and select the most promising yeast and optimize the production of biomass and crude protein. The yeasts used in this study were Aureobasidium pullulans EBJ31, Candida (Metschnikowia) pseudointermedia CAC01, Rhodotorula mucilaginosa CCC31, Wickerhamomyces anomalus CCC32 and Trichosporon asahii EPB13. W. anomalus CCC32 was the most promising strain for SCP production and was selected for the optimization studies of biomass and crude protein production by Rotational Central Compound Design (DCCR). A factorial planning matrix of type DCCR 23 was used and the studied variables were crude glycerol, NaNO3 and urea. After optimization, the maximum biomass production was about 20 g/L and the crude protein concentration was 33% at 84 h, using crude glycerol 25 g/L, NaNO3 3.5 g/L and 6.5 g/L urea, at 30 ° C and 150 rpm. The results indicated that the crude glycerol can be used as a substrate for the production of SCP by yeasts, being an alternative to add value to this residue. W. anomalus CCC32 presented favorable characteristics for SCP production as fast growth, high biomass production with high crude protein content.