CULTURAL CHARACTERISTICS OF LIPID ASSIMILATING YEAST, MEYEROZYMA GUILLIERMONDII TY-89

Microbial utilization of lipid will be significant in supplying protein for animal and fish consumption from safe and cheap raw material, and in resolving the treatment of waste lipid. We carried out study on cultural condition of lipid assimilating yeast, Meyerozyma guilliermondii TY-89 using vegetable oil. The medium contained commercial vegetable oil ( the mixture of soybean oil and rapeseed oil ) as a sole carbon source, ammonium sulfate as a nitrogen source, and some minerals. One hundred ml of the medium in a 500 ml Erlenmeyer flask was inoculated with 4 ml of precultured broth and incubated at 30 degree celsius. When cultivating this strain in Erlenmeyer flasks with buffles on a rotatory shaker (120 rpm), cell growth was better than that in Erlenmeyer flasks without buffles. The buffles can change large droplets of the vegetable oil to small ones. It seems that small droplets of the vegetable oil were assimilated more rapidly than large ones. The ammonium group was effective as nitrogen source, nitrogen of the nitrate group was hard to assimilate. This strain can grow below pH 2.0 and the addition of ammonia water was effective cell growth. These results suggests that this strain is suitable for making yeast biomass from lipid.