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 Grdm's method. 



Growth. — ^Abundant, though somewhat slow. 



Qelatin plates. — Colonies are small, round, elevated, moist and 

 pink-colored and coarsely granular. 



Stab cultiire. —Growth, absent from the lower part of the tube. It 

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

 covering. 



Streak cultv/re. — 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, S. 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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