OTHER BACTERIA 



107 



The antagonistic effects of lactic acid bacteria of the L. bulgarkus and 

 L. acidophilus groups have received considerable attention, especially 

 in regard to their action against intestinal bacteria. This was believed 

 to be due to the production of acid by the bacteria rather than to the 

 formation of specific antagonistic substances. This phenomenon aroused 

 particular interest because of the function of some of these organisms in 

 replacing bacterial inhabitants of the human digestive system (526). 



Various bacteria also have a marked destructive effect upon plant 

 pathogenic fungi, as will be shown later. Some produce stable, heat- 

 resistant, antifungal substances (731 ). 



