| Popis: |
Yeast killer factor, an unstable protein-containing macromolecule, was found to be markedly stabilized by ammonium sulfate and polyhydric alcohols such as glycerol, erythritol and mannitol. Quantitative studies on the effects of glycerol were further conducted under various conditions. The killer activity was retained unchanged in 30 % glycerol solution, for instance, for at least 10 days at 25°C while it disappeared within 12 hr in the solution without glycerol. However, the killer factor was still unstable at the temperatures above 35°C or beside the pH ranges 4.5~5.0 even in the presence of 20% glycerol. Glycerol was also found to be effective for the production of the killer factor. Availability of glycerol for purifying the killer factor is discussed. |
