Efficiency of synthesis of extracellular polysaccharides strains of Lipomyces yeast

Abstract

The formation of extracellular polysaccharides is a fairly well-studied property of bacteria that is used for the industrial production of such extracellular bacterial as xanthan, dextran, gellan, hyaluronan, etc.. Polysaccharides synthesized by fungi are also widely used, such as schizophillan and scleroglucan. However, polysaccharides synthesized by yeast and yeast-like fungi have not yet found wide industrial application, with the exception of pullulan produced by Aureobasidium pullulans yeast, although there are a number of promising developments in the use of yeast polysaccharides in medicine. Yeast synthesizes polymers that contain mannans, glucans, phosphomannans, galactomannans, and glucuronoxylmannans. Polysaccharides produced by different species, and sometimes even by different strains of the same species, may differ in chemical composition and structure. Such a variety of composition and properties opens up great prospects for their use in various fields: medicine, chemical, food and cosmetic industries, as well as feed additives. In this regard, the search for new producers of polysaccharides is very relevant. Yeast of the genus Lipomyces is found in the soils of the southern and northern hemispheres of the Earth, except in the high-mountainous regions and tundra soils, where soil formation processes are in early stages of development, but the soils are rich in steppe and forest zones. As a result of the research, it turns out that from the point of view of biomass growth on the presented nutrient medium at the temperatures studied, the strains of the Lipomyces lipofer yeast КБП Y-6267 and КБП Y-6265 attract the most attention, especially at low temperatures. With an increase in temperature, the increase in biomass in these yeasts decreases markedly. As producers of extracellular polysaccharide, it is worth noting the КБП Y-6267 and КБП Y-6264 strains at 20 °C and the КБП Y-6268 strains and the КБП Y-6234 at 30 °C, which indicates the possibility of using for these purposes different species of the genus Lipomyces. At 30 °C, Lipomyces lipofer strains of the КБП Y-6268 and Lipomyces kononenkoae КБП Y-6234 had the highest enzyme activities, however, there was no relationship between enzyme activities, biomass gains and polysaccharide yields at low temperatures.