The effects of phloridzin and other substances on fermentations by yeast

Abstract

Phloridzin shows a much higher retarding action on the normal rate of zymin fermentation of glucose than salicin, aesculin or amygdalin, this being especially marked when relatively small quantities are used. Under the experimental conditions, 10-4 g.-mol. phloridzin effects a 31% retardation and 10-3 g.-mol. a 59% retardation in rate of fermentation due to zymin. Phloretin shows a similar but somewhat less vigorous action than phloridzin. The rate of fermentation after addition of phloridzin is linear. Of the polyhydric phenols, phloroglucinol (the phenol present in phlorid-zin) is most effective in retarding rate of fermentation of glucose by zymin. The retarding action of phloridzin is not exhibited in zymin fermentation of pyruvic acid, or in fermentations of glucose and pyruvic acid by live yeast. Allyl alcohol and acrylic acid retard fermentation of glucose by zymin and live yeast, retardation increasing with time. Neither allylamine nor allylacetic acid has such an action under the conditions of the experiments.