DWI ARYANTI NUR’UTAMI, LIESBETINI HADITJAROKO AND KHASWAR SYAMSU
Abstract
The aim of this study was to assess the tolerance of two genetically modified Saccharomyces cerevisiae, Pro1(I150T) and Mpr1(K63R) in hyperosmotic stress and to measure the kinetic parameters of them in the production of bioethanol in high sugar concentration media. The results show that all genetically modified yeast could grow in media up to 70% sucrose and 13% ethanol. The values of all kinetic parameters (except Yp/x value) of the yeast strains were not different significantly. Mpr1(K63R) had the highest value of Yp/x. It was about 4.84±0.07 g ethanol/g biomass. All genetically modified yeast strains produced high amount of ethanol which were higher than those in industry, it was about 139.55±5.59 g/ L for Pro1 (I150T) and 147.75±3.61 g/L for Mpr1(K63R). These two genetically modified yeast strains are recommended to be used in bioethanol industry to increase the ethanol production.