The effect of Zn, Mn and Cu ions on erythritol production from glycerol by Yarrowialipolytica yeast

DOI: 10.5176/2251-2489_BioTech13.61

Authors: Ludwika Tomaszewska, Anita Rywińska, Waldemar Rymowicz

Abstract:

Erythritol is very low caloric value sweetener. Its production in chemical processes is not effective,hence it is produced in microbiological processes. The aim of the study was to examine the impact of zinc, copper and manganese ions on the production of erythritol from glycerol and their impact on the activity of erythrosereductaseinY.lipolyticaWratislaviaK1.

In the shake-flasks experiment glycerol medium was supplemented with ions:Zn2+(1050mg/L), Mn2+(2.5200mg/L) and Cu2+(2.515mg/L). The highest concentration of erythritol(27.2g/L) was obtained in the culture with 20mg/LofZn2+. The doses of ions:20mg/LofZn2+, 25mg/LofMn2+ and 2.5mg/LCu2+ were chosen for further studies in bioreact or cultures. In the bioreactor cultivations the highest erythritol concentration was obtained with Mn2+ and Zn2+ ions addition and reached 46.9 and 40.3g/L, respectively. The yield of the biosynthesis was the highest (0.46g/g) in the culture with Mn2+ ions, whereas the best results of productivity (0.77g/Lh) and specific production rate (0.052g/gh) was observed with Cu2+ ions addition. The erythrose reductase activity was measured in the samples taken fromb io reactor cultures in 24-hour of the cultivation.It was observed that ions addition increased the activity of the enzyme. The highest activity of erythrosereductase (24.814U/gofDW) was obtained in the culture with Mn2+.It is probably the first study concerning the enzymes activity during the erythriol biosynthes is from glycerolbyY.lipolytica.