1910. | Oxidation of Phenol by Certain Bacteria. Je 
IL. Action of the Chromogenic Organism on Phenol. 
(a) Broth Cultwres—Experiments were first conducted with broth 
cultures of this organism. A few cubic centimetres of a broth culture were 
added to a pure phenol solution. 
For two or three days no change was noted in the solutions ; subsequently, 
however, the disappearance of phenol was rapid, the whole being completely 
oxidised in five or six days from the commencement of the experiments. 
Typical example :— 
Oxygen absorbed from acid 
permanganate solution in 3 minutes. 
Parts per 100,000. 
April 9. Experiment commenced ......... 25°20* 
Ml ess ae a ogee 25°80 
CA naw acsmeaaasdesicnc taeee mee skies anes ae 2°00 
Pre 1D Sodsm csi enisijasmearousense esas nseecaseoe 1°57 
* Equivalent to 16°5 parts of phenol per 100,000. 
The 3 minutes oxygen absorption test was chosen as the most convenient 
for the detection of phenol and its approximate estimation. The accurate 
determination of phenol in such dilute solutions would be a long and tedious 
process, while the amount of oxygen absorbed by the constituents of the 
broth or its products of decomposition bears a very small proportion to the 
amount taken up by the phenol. 
(b) Diluted Broth—An experiment was made using about 30 c.c. of a 
diluted broth culture in place of ordinary broth. Again it was noticed that 
no change took place for a few days, followed by rapid disappearance of phenol. 
The time taken to complete the experiment was eight days, or rather longer 
than with ordinary strength of broth. 
Two experiments were afterwards made with diluted broth cultures 
(35 cc.) with the addition of a few cubic centimetres of ordinary sterile broth. 
As before, no change was noted in the earlier stage of the experiment, but 
after four days only, complete. oxidation was rapidly brought about in 
24 hours. The air passing through these solutions was previously sterilised 
by bubbling through mercuric chloride solution. 
Example :— 
| Oxygen absorbed from acid 
permanganate in 3 minutes. 
Parts per 100,000. 
June 27. Experiment commenced ......... 24°8* 
MMO ee Aree sels tel aac susuoceses 24'8 
PMs Ore eee rel tane ea ticslor cidiehe sles nie cleuleids/pianoitielene 24°8 
St ae Bh 8 os cogtsezcseaetes 29:8 
POM Pee ese se cite eiclleis'sininic: ds oamsiaisieis va warsiae 1°2 
* Equivalent to 16°2 parts of phenol per 100,000. 
