Production of galactooligosaccharides and biosurfactants by Pseudozyma tsukubaensis using cassava wastewater as an alternative pre-inoculum medium

摘要

Yeasts from Pseudozyma genus are well known producers of important bioproducts, includingbiosurfactants and galactooligosaccharides. The objective of this study was to synthesizegalactooligosaccharides, from lactose, by Pseudozyma tsukubaensis using cassava wastewater as the preinoculummedium to produce biosurfactants and β-galactosidase. P. tsukubaensis was able to grow and toproduce biosurfactant on cassava wastewater, reducing the surface tension of medium to 26,09 mN/m after36 hours in 30°C/150 rpm. Biomass production increase rapidly within 36 h of growth, and reached themaximum biomass weight in culture (2.55 g/L) at 48 h. The transgalactosylation activity of the yeast cellsfrom 40% (w/w) lactose resulted in a maximum galactooligosaccharides production of 71,1 g/L and a yieldof 17,78% (w/w) at pH 8,0 and 30°C in 24 hours. The results obtained in this study demonstrate for the firsttime the potential of P. tsukubaensis to produce galactooligosaccharides from lactose and its ability to growthin cassava wastewater producing biosurfactants in this medium. More research has been done to evaluate andoptimize this process.