Determination 01 some optimum conditions for produetion of a killer toxin AY from the yeast saccharomyces cerevisiae

الملخص EN

Four samples of commercial br^d of ready powdered Saccharomyces cerevisiae were collected from local market (Town and Angel/ China , Saf/ France and Pakmaya/ Turkey) for detection their ability to produce killer toxin against eleven isolates of microorganisms: Lactobacillus acidophilus , Pseudomonas aeruginosaو Pseudomonas fluorescens, Staphylococcus aureus , Serratia marcescens , Cladosporium spp., Fusarium spp., Aspergillus spp.

and three isolates of Candida albicans , as well as s.

cerevisiae isolates.

Results showed that Angel yeast was the best one for production of killer toxin ,no production of killer toxin was observed by other isolates of ،S', cerevisiae.

Also some optimum conditions for production of killer toxin was determined and the results showed that cultivation of yeast in glucose yeast extract peptone broth(GYE?B),adjusted at pH 5 and incubated at 25°c for 48 hours was the best to produce it.