[Biomass accumulation by polyploid forms of Candida guilliermondii yeasts]

Under the action of a mitotic poison (acenaphthene), the haploid culture of Candida guilliermondii assimilating n-alkanes yielded a polyploid form whose cells were four times larger, on the average, than in the haploid culture. When the pure culture was grown under stationary conditions in media with glucose, the economical coefficient, i. e. the ratio between the assimilated glucose and the accumulated biomass, was by 16, 47 and 157% higher in the polyploid culture than in the haploid one after 24, 48 and 72 hours, respectively. The amount of biomass and the content of protein in it were the same in the haploid and diploid cultures grown in liquid nutrient media with n-alkanes. Cells of the polyploid culture were always larger in media containing n-alkanes, which facilitated separation; no cells were found after it in the cultural fluid. Not all cells of the haploid culture could be separated; therefore, the polyploid culture had the advantage over it. The polyploid cultures of C. guilliermondii were very stable when stored in the lyophilized state. Their morphological and physiological properties did not change within two years.