The industrial distillery yeast Saccharomyces cerevisiae was determined for its capacity to ferment monosaccharide lactose derivatives. Analyses were carried out to examine their natural predisposition for fermentation of media with lactose hydrolysates (12%) and in addition, the rate of saccharides utilization in the experimental fermentation medium (6% glu/6% gal) was monitored as affected by the method of preliminary propagation of yeast: on standard medium with glucose or on adaptive media with galactose or mannose. It was demonstrated that the level of lactose derivatives attenuation by the yeast examined did not exceed 4% v:v alcohol. A chromatographic analysis of the saccharides enabled determining the rate of their utilization in the fermenting mixture. The effect of delayed utilization of galactose by the yeast was found to be evoked by the phenomenon of glucose repression. The preliminary propagations of the analyzed yeast on adaptive media before the fermentation process caused the acceleration of galactose assimilation, resulting in increased alcohol content in fermented media to 4.2-4.4% v:v.

Yarrowia lipolytica Wratislavia AWG7 yeast strain was immobilized in different kind of chitosane and PVA gels and used for biosynthesis of citric acid from glycerol. The yeast strain produced citric acid in the range from 0 to 17,5 gl^-1 in 7-days shake flask. Chitosane biocatalyst type of CH+TP+AG and polivinylalcohol biocatalyst type PVA+A produced citric acid with the highest production rate and the yield; 2,5 gl^-1d^-1, 0,54 gg^-1 and 2,5 gl^-1d^-1, 0,52 gg^-1, respectively.

Abstract: An utilization of the oily waste from the food and automotive industry is both one of the most important and hard challenge for the environment protection. In this work the attempt to select the microorganisms able to biological assimilation of atypical carbon source has been introduced. The development of prowess enzymatic abilities in these microorganisms can be induced by stressogenic environment of live and enables the utilization of harmful wastes. To isolate the microorganisms a special niche was chosen, into which few different, strong detergents that inhibits the growth of microorganisms were applied. As a result of the multiphase isolation 22 strains were obtained, 18 yeasts from Candida, Trichosporon, Geotrichum and Pichia type, and 4 bacterias. Every of the microorganisms surveyed had a high ability to the oily waste assimilation. A culture with a complex carbon source, like oils from the food and automotive industry, gasoline and air-fuel was made. In the result high biomass growth was observed. Selected activities of the hydrolase were evaluated and they showed high enzymatic abilities of the tested isolates. As a model organisms, which the abilities of growth on the hard – degradation compounds were compared with, microorganisms with utilization of petroleum derivatives abilities were chosen : Yarrowia lipolytica and high-capable of lipid-degradation Geotrichum candidum.