USE OF SHAKEN CULTURES IN THE ASSIMILATION TEST FOR YEAST IDENTIFICATION

Abstract

The growth of isolates of yeasts, from Biscayne Bay, Florida, in various assimilatory media was examined in both standing and shake cultures. The use of agitation was found to reduce the incubation time from 3 weeks to approximately 1 week or less. Nonfermentative yeasts, particularly those of the genus Rhodotorula, which commonly assimilate carbohydrates by adaptive or slow growth, and often give indefinite results in standing culture, were found to increase their assimilation under agitation. The. methodology employed offers a rapid means of obtaining the assimilatory spectrum of yeasts as well as a more critical evaluation of the growth of slow and latent forms.