FEKMENTATION OF POLYSACCHARIDES 225 



Starch appears in plant tissues and plant cells in the form 

 of starch grains. These are insoluble in cold water. The 

 starch has the empirical formula (C G H 10 5 ) n . Inulin on 

 the other hand is soluble in cold water, does not form gran- 

 ules in plant tissues, but is widely distributed in the great 

 family of plants known as the composites. It is abundant, 

 for example, in the sunflower, the dahlia, the dandelion and 

 chicory. It has the same empirical formula as starch. 

 Upon hydrolysis starch breaks down through a series of 

 dextrins to maltose and finally to dextrose. Inulin, on the 

 other hand, breaks down through a series of intermediate 

 compounds to fructose (levulose). 



Starch and inulin may be fermented in two principal 

 ways. Some microorganisms hydrolyze the complex carbo- 

 hydrates into simpler compounds, finally forming sugar. 

 They may or may not utilize the sugar thus formed, though 

 usually they do. Other microorganisms break down starch 

 but utilize the intermediate products, changing them into 

 acids, gases, Acetone and other compounds. In this process 

 sugar apparently is never formed or at least, if formed, is 

 so evanescent that its presence is not detected. 



Microorganisms capable of bringing about hydrolysis of 

 starch are of considerable economic importance. It has 

 already been noted that certain fungi may be utilized com- 

 mercially in the transformation of starch into sugar pre- 

 liminary to the manufacture of alcohol in the so-called 

 amylomyces process. Apparently the first utilization of 

 fungi for saccharification of starch was in oriental coun- 

 tries, probably in China. The Chinese use this method in 

 the preparation of a medium for the growth of yeasts in the 

 manufacture of Chinese whisky. Rice is first softened by 

 boiling, mixed with chopped rice straw, and made into 

 cakes. These cakes are exposed to the air and allowed to 

 mold. The molds most frequently occurring are certain 

 species of Aspergillus, particularly Aspergillus oryzce, and 

 several species of Mucor and Rhizopus. When the mold is 



