Optimization of biomass production with copper bioaccumulation by yeasts in submerged fermentation

Abstract

The objective of this work was to study the production of biomass with copper bioaccumulation in submerged fermentation using sugarcane molasses. Candida pelliculosa BARU 05 isolated from Baru (Dipteryx alata) was selected for its good capacity to accumulate the copper. Fermentation was carried out using the medium composed by sugarcane molasses at 5 °Brix enriched with (g/L) CuSO4.5H2O 0.1; yeast extract, 10.0; (NH4)2SO4, 5.0 ; KH2PO4, 5.0 MgSO4, 0.5, inoculum 10 % of total volume (100 ml), pH 6.0, and incubation at 30 °C, 120 rpm for 120 h. After three steps of optimization an uptake of 95.04% and 13.397 g/L biomass were obtained. The kinetics of copper bioaccumulation and biomass production was followed in a 10- liter bioreactor in a batch and fed-batch fermentation which showed copper accumulation of 91.98 and 100 %, respectively, and biomass production of 38.85 g/L (24 h) and 57.54 g/L (48 h), respectively.

Keywords

• Bioaccumulation
• baru
• yeast
• copper
• sugarcane molasses