Dichlorofluoromethane inactivates Saccharomyces cerevisiae

Area of Science:

• Microbiology
• Biochemistry
• Food Science

Background:

• Saccharomyces cerevisiae is a key yeast species used in various industrial applications.
• Understanding microbial inactivation is crucial for food preservation and sterilization processes.

Purpose of the Study:

• To investigate the inactivation kinetics of Saccharomyces cerevisiae by dichlorofluoromethane (f-21).
• To identify factors influencing the efficacy of f-21 as a yeast inactivating agent.

Main Methods:

• Incubation of Saccharomyces cerevisiae in aerosol cans with YM broth and dichlorofluoromethane (f-21).
• Determination of viable cell counts using broth inoculation and plate count methods.
• Assessment of inactivation under varying f-21 concentrations, broth volumes, temperatures, and agitation levels.

Main Results:

• Yeast inactivation was enhanced by increased f-21 concentration, larger broth volumes, higher temperatures (7-47°C), and agitation.
• Younger yeast cells (8h) and those grown without glucose exhibited greater susceptibility to f-21.
• Adjusting pH, pre-treating with f-21, or distilling f-21 did not affect yeast viability.
• Inactivated yeast cells showed increased resistance to sonic disruption compared to viable cells.

Conclusions:

• Dichlorofluoromethane (f-21) demonstrates significant potential for inactivating Saccharomyces cerevisiae.
• Factors such as chemical concentration, temperature, cell age, and growth medium composition critically influence inactivation efficiency.
• Further research into f-21's application in sterilization and preservation may be warranted.