Effect of ethanol on the metabolism of Euglena gracilis

Abstract The effect of ethanol on Euglena gracilis metabolism has been studied. It was found that ethanol greatly enhances the incorporation into paramylon of both the carboxyl and methyl carbon atoms of pyruvate. The respiration to CO 2 of glucose and pyruvate, as well as their incorporation into lipids and proteins were inhibited by ethanol. The glycolytic conversion of glucose into pyruvate was also inhibited, while a larger percent of glucose was incorporated into paramylon. Ethanol itself was rapidly oxidized to acetate, part of which is secreted into the medium and a significant part of the ethanol methyl carbon was incorporated into paramylon. It was concluded that the addition of ethanol to Euglena cultures diverts the metabolic utilization of all other endogenous and exogenous carbon sources towards gluconeogenesis and paramylon synthesis.