

THE EFFECT OF CARBON DIOXIDE ON BACTERIA 



By GEORGE VALLEY 



Sterling Research Fellow, Laboratory of General Bacteriology, Yale University 



IN 1848 Bethell patented a process for 

 preserving milk by carbonation, 

 which consisted in first boiling the 

 milk to expel all the air contained 

 in it and then saturating it with carbon 

 dioxide. The milk, it was claimed, 

 remained fresh for a long time after being 

 exposed to the air. This process is more 

 or less of prehistoric interest, since no 

 evidence has survived to show how suc- 

 cessful it was in its application. 



DESTRUCTIVE EFFECTS OF CARBON DIOXIDE 



Pasteur and Joubert (1877) observed 

 that B. anthracis is killed in carbon 

 dioxide. No mention is made of the 

 media that were used in their experiment, 

 nor is it stated how long the exposure to 

 the gas continued, or how much carbon 

 dioxide was required to react fatally to 

 B. anthracis. Szpilman (j88o) suggests 

 that the above claim should be qualified 

 somewhat, since he, Szpilman, showed 

 definitely that from five to eight hours' 

 exposure to an almost pure atmosphere of 

 carbon dioxide did not kill B. anthracis, or 

 even alter the pathogenicity. Grossmann 

 and Mayerhausen report (1881) that C0 2 

 does not kill bacteria, but that it inhibits 

 motility. Small amounts of C0 2 increased 

 motility. Buchner (1885) has shown 

 that the effect of carbon dioxide gas is 

 variable. It inhibited Koch's Vibrio, 

 but development was obtained with 

 Fitch's Aethylbacillus, the Napel cholera 

 bacillus and Bact. typhosum. 



In 1885 and 1886 a series of papers by 



Pfuhl, Sohnke, SchafFer and Freudenreich, 

 and Kolbe appeared. The investigations 

 of Pfuhl and Sohnke dealt with the 

 microorganisms found in carbonated wa- 

 ters. SchafFer and Freudenreich reported 

 that typhoid and anthrax bacilli were 

 unaffected in broth cultures under seven 

 atmospheres of carbon dioxide pressure. 

 Kolbe's work was an attempt to preserve 

 meat and fruit in an atmosphere of carbon 

 dioxide. Beef could be preserved for 

 eighteen days, while mutton showed 

 spoilage in a very short time. 



Liborius (1886) failed in his attempts to 

 initiate growth of CI. foetidmn, CI. polyp- 

 ifonnis, CI. oedematis-maligni and B. 

 psettdo-oedematis when carbon dioxide was 

 passed through the medium. However, 

 when it was passed over the surface of the 

 medium some growth was obtained. 

 Bolton (1886) reported a limited number 

 of experiments with M. aqiiatilis and B. 

 erythosporus . The results were erratic; 

 inhibition was obtained in some cases 

 but not in others. The duration of C0 2 

 treatment is not given. These experi- 

 ments were carried out in water con- 

 taining only traces of organic matter. 

 Destruction of bacteria was also evident 

 under hydrogen. 



Leone's work appeared in a German 

 translation in 1886, and concerned itself 

 with the reduction of bacterial numbers 

 in the city water of Munich. Reduction 

 was obtained, but complete sterilization 

 was never reported. The statement was 

 made that pressure was not a factor in 



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