EFFECT OF CARBON DIOXIDE ON BACTERIA 



tial. It is, nevertheless, interesting to 

 note that the acid-sensitive micro- 

 organisms, such as V. cholerae, B. ant bra- 

 cts, etc., were most easily inhibited. 



Frankland (1889) reported his experi- 

 ments with V. cbokrae, the Finkler- 

 Prior vibrio and the organism of blue- 

 green pus. His results are on the whole 

 in accord with Frankel's findings. He 

 pointed out that certain differences in 

 their results may be explained by varia- 

 bility in resistance of strains used. He 

 confirmed Frankel's observation that the 

 majority of the organisms succumb readily. 

 However, a small per cent remained alive 

 and even multiplied to a certain extent. 



Scala and Sanfelice (1891) investigated 

 the effect of dissolved carbon dioxide in 

 natural waters. It appeared that the 

 pathogenic organisms, V. chokrae, B. 

 anthracis, Staph, aureus and albus, Bact. 

 typhosum and Bact. lepisepticum were not 

 affected by the quantities of C0 2 naturally 

 dissolved in water at i5°C. When the 

 water was saturated with C0 2 , V. chokrae 

 and B. anthracis were injured, while others 

 remained apparently indifferent. Carbon 

 dioxide under pressure in soda-water was 

 injurious to B. subtilis, while Proteus 

 vulgaris remained unaffected. Spores of 

 B. subtilis and B. anthracis did not ger- 

 minate. 



BACTERIA REQUIRING CARBON DIOXIDE 



During the years 1890 to 1899 a very 

 interesting observation was made and 

 proven to be a fact, namely that though 

 carbon dioxide exerts injurious effects on 

 certain bacterial species, it is actually 

 required by others. Vinogradsky (1890) 

 and Vinogradsky and Omeliansky (1899) 

 in a series of articles showed that the 

 nitrifying organisms require carbon diox- 

 ide, utilizing it as a source of carbon. 

 Godlewsky (i89x) confirmed the original 



observation of Vinogradsky. These find- 

 ings have been confirmed more recently 

 by Meyerhof (191 6-17) and Bonazzi 

 (19x1). 



Considerable controversy developed be- 

 tween d'Arsonval and Charrin (1893) an( ^ 

 Sabrazes and Bazin (1893). The former 

 had recommended for the sterilization of 

 organic filtrates an application of carbon 

 dioxide under pressure of 50 to 60 atmos- 

 pheres. They also reported, however, 

 that Ps. pyocyanea cultures in broth were 

 not killed under the given pressure of 

 carbon dioxide during six hours' exposure. 

 Sabrazes and Bazin repeated the work of 

 d'Arsonval, but could not confirm his 

 claims, even at higher pressures than those 

 indicated by d'Arsonval, who suggested 

 that certain organic liquids, such as blood, 

 milk and urine, could be preserved in this 

 manner. Sabrazes and Bazin experi- 

 mented with Staph, aureus, Bact. coli, B. 

 anthracis and Bact. typhosum, arriving at the 

 conclusion that pressures of 90 atmos- 

 pheres and beyond do not injure B. 

 anthracis or Staph, aureus. 



It would be of doubtful value to employ 

 C0 2 for sterilization of organic liquids 

 within the time limits fixed by d'Arsonval. 

 In his reply to Sabrazes' criticism, d'Arson- 

 val claimed that the differences in results 

 were obviously due to differences in 

 experimental technic. The sterilization 

 in his experiments was effected with 

 filtrates made up with glycerine to 15 or 

 zo° Baume. It was, therefore, the com- 

 bined action of glycerin and of C0 2 

 under pressure which was responsible. 

 He states very judiciously that "quant 

 aux conditions de pression, de duree, de 

 temperature, de composition chimique et 

 de milieu necessaires pour tuer les 

 differents microbes pathogenes, c'est la 

 une determination pour laquelle je ne me 

 suis pas send une competence suffisante." 





