376 Microbes and You 



ing agent, as a solvent, as a compound of anti-freeze, and as a con- 

 stituent of medicines, inks, adhesives, and gunpowder. 



The high fat content of some strains of yeasts provides a source 

 of this substance for certain commercial applications. During 

 World War I when the Germans were faced with a shortage of gun- 

 powder, it is reported that they employed the false yeast Torula 

 lipofera, which is exceptionally well suited to converting simple 

 compounds into fat, for the manufacture of fat which in turn was 

 converted into nitroglycerine. As much as 20% dry weight of these 

 yeast cells may be composed of fat. 



SPOILAGE 

 The principal yeast offenders in the spoilage of food are mem- 

 bers of the family Torulaceae, which produce pigments and un- 

 desirable chemical end products during their metabolism. So- 

 called "bloody sauerkraut" may be caused by pigmented yeasts, and 

 the colors sometimes found in milk and dairy products are fre- 

 quentlv traced to the growth of false yeasts. Many foods not 

 usually attacked by bacteria because of the low pH are readily em- 

 ployed as a substrate by yeasts which can tolerate and thrive at pH 

 levels not conducive to bacterial growth. Members of the Rhodo- 

 tondaceae (red false yeasts) may be particularly troublesome in 

 places where oysters are shucked, and in butcher shops. 



DISEASE 



A few yeasts are pathogenic for man and for lower animals. 

 One such disease is caused by Candida albicans which affects the 

 throat, mouth, and other parts of the body. This veast, according 

 to Diddens and Loder, has eighty-eight synonyms. The disease 

 is called moniliasis, and when it causes ulceration of the mouth 

 and throat, it is tenned "thrush." If the organisms invade the 

 stomach and intestines, they may cause an ulcerative condition 

 accompanied by diarrhea; this disease is "sprue." 



In cases of thrush characteristic patches of creamy, membranous- 

 like material are found, and stained smears prepared from material 

 taken directly from the lesions reveal an abundance of the causative 



