MANNITOL-PRODUCING ORGANISMS IN SIL.\GE 439 



It seems then that only fructose, or materials giving fructose 

 on hydrolysis were capable of yielding mannitol when acted on 

 by the mannitol-producing organisms studied. The small 

 amount of mannitol produced in the inulin stover silo, as well 

 as in many of the sucrose stover silos, was undoubtedly due 

 to the inability of the organisms to hydrolyze these materials 

 and to the small amount of hydrolysis which occurred during the 

 process of sterilization. The variations in the amounts of 

 mannitol produced in the sucrose stover silos were very likely 

 due to differences in the amount of hydrolysis, and this was 

 materially influenced by the amount of acid present and by the 

 extent of the heating. Gayon and Dubourg (1894; 1901) 

 found that only fructose or its moiety yielded mannitol and 

 Brown has shown how the configuration of fructose is such that 

 it alone can be changed to mannitol by organisms. 



It is entirely possible that certain organisms may be able to 

 produce mannitol from such materials as sucrose and some 

 results have been secured which indicate that one of the cultures 

 isolated is able to do this. It seems quite certain, however, 

 from results secured with the use of bouillon to which sucrose 

 was added, that most of the cultures isolated are unable to 

 change sucrose to mannitol. 



Distribution of the mannitol-producing organisms 



Since mannitol is a normal silage constituent and is produced 

 by the action of microorganisms, it would be expected that 

 mannitol-producing organisms would be rather widely distrib- 

 uted about barns where silage is used, due to the scattering of 

 silage and of manure from animals consuming silage. A number 

 of materials have been tested for mannitol-producing organisms 

 by inoculating them into sterile corn juice, flooding the juice with 

 sterile oil in order to keep down the growth of molds and then 

 determining the presence or absence of mannitol after a suitable 

 incubation period at room temperature. The production of 

 mannitol has been secured with soil from a farm yard and also 

 with milk, but the trials made are too few in number to allow 

 of any conclusions regarding the extent of the contamination 

 of these materials. 



