The Use of Adenylate Kinase Measurement to Determine Causes of Lysis in Lager Yeast

摘要

The measurement of adenylate kinase activity in the supernatants of yeast suspensions was used as an indicator of yeast lysis. Activity was measured in the supernatants of aerobically propagated yeast suspensions, grown in wort or malt extract-yeast extract-glucose-peptone (MYGP) broth with and without various supplements. It was determined that the number of adenylate kinase units released by three production lager strains were similar under similar conditions, although variants of one strain displayed significant differences. Osmotic stress proved to have no effect on the number of adenylate kinase units released, whereas a substantial increase was observed when yeast was grown in the presence of ethanol. Ethanol addition to stationary-phase yeast resulted in small increases in the number of adenylate kinase units released.