Chapter V 



9B 



Metabolism 



diluted with water and fish (trout) were placed in it for 1 hour, they 

 absorbed sufficient odor to become markedly tainted and unpalatable 

 (418). 



IssATCHENKO (182) emphasized the importance of the odor imparted 

 to river waters by the actinomycetes in rendering such water unpalat- 

 able. In view of the fact that actinomycetes are able to develop at a 



I^QUS o/^ lncu6ation 



Fig. 21.— Decomposition of hemicelluloses by actinomycetes, as measured by CO2 

 evolution Qfrom Waksman and Diehm, 462). 



much more reduced oxygen pressure than that of the atmosphere (1/ 

 25), the large numbers found in the surface layers of the bottom de- 

 posits are able to grow rapidly and produce an intense odor. If the 

 bottom is sandy, most of the odor will dissolve in the water; if the bot- 

 tom is clay, the odoriferous substance will be retained and will accumu- 

 late. 



Odoriferous substances may also be produced by actinomycetes on 

 caqao beans (55), milk (120), and other foodstuffs, rendering them 

 inferior in quality or totally unsuitable for human consumption. 



