Abstract
Biological characterisitcs of Saccharomyces cerevisiae and Candida robusta, including haploid and diploid strains, were investigated by the colonial dissociation method aand variation rate in sugar fermentation and sugar assimilation was surveyed. Results were as follows : 1) By adding yeast extract to the basal medium for the sugar assimilation test, the inoculum could be reduced as much as 1/2 to 1/4 of the usual method. 2) Using the improved half slant medium, accuracy of the sugar fermentation test was increased, Moreover, by this method, many of the non fermentor were proved to be formentable of the used sugar. i.e. in the non fermenter, many latent fermentters were recognized. 3) Variation rate of both fermentation and assimilation reaction were so high that these charateristics did not seem to be controled genetically by so called mitosis of the chromosomes. 4) Referring to the results of the previous report, it comcluded that the nuclear substance of the yeasts did not exist as chromosomes.
