Saccharomyces Glutinis. 



RED YEAST. 



ORIGIN. Very common in the air, from which several 

 distinct kinds of red yeast have been obtained. 



COLOR. Red or pink. 



FORM. Round or oval cells with granular protoplasm 

 which stains irregularly. Cells single or in pairs, budding-. 

 MOTILITY. None. 

 SPORULATION. None. 



ANILIN DYES. It stains readily, also by Gram's method. 

 GROWTH. Abundant, though somewhat slow. 



Gelatin plates. Colonies are small, round, elevated, moist and 

 pink-colored and coarsely granular. 



Stab culture. Growth absent from the lower part of the tube. It 

 spreads slowly over the surface, forming- a thick, moist, bright red 

 covering. 



Streak culture. On agar, it develops in a few days as a thick, 

 slimy, spreading, pink-colored growth. On potato, it forms the same 

 pigment. 



TEMPERATURE. Grows best at ordinary temperature. 

 BEHAVIOR TO GELATIN. Does not liquefy. 

 AEROGENESIS. Does not change glucose to alcohol. 

 PATHOGENESIS. No effect on animals. 



A white yeast is frequently deposited from the air. 

 The cells are usually smaller than those of the red yeast. 



A black yeast, 8. niger, forms a brownish or black 

 growth. The size of the cell is about the same as that of 



the red yeast. It grows very slowly. 



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