149 
The Oxidation of Phenol by Certain Bacteria in Pure Culture. 
By GILBERT J. FOWLER, EDWARD ARDERN, and WILLIAM T. LOCKETT. 
(Communicated by Dr. A. Harden, F.R.S. Received September 30,— 
Read November 17, 1910.) 
In the course of investigations on the effect of various antiseptic substances 
on bacterial sewage filters, it was found that solutions of pure phenol could 
be oxidised on filters of this description. It was further found that the 
phenol apparently exerted a selective action on the bacteria present in the 
filter, only three or four types of organism appearing in the filtrates. 
Of these about half were liquefying organisms, identified as B. liquefaciens 
jluorescens. At first it was thought that the main non-liquefying, or 
extremely slowly liquefying, organism was 5. fluorescens non-liquefaciens, on 
account of the apparently fluorescent yellow colonies it produced ; subse- 
quent investigation showed that this was not the case (see note at end of 
paper). It is therefore referred to in the paper simply as the chromogenic 
organism. 
On passing a current of filtered air through the liquid containing a mixture 
of these organisms, together with small quantities of phenol, the latter was 
slowly oxidised, which was not the case in a control experiment where 
organisms were absent. 
Preparation of Pure Cultures. 
The survival of the particular organisms—B. liquefaciens fluorescens and 
the chromogenic organism—in the experiments referred to, and their 
constant presence in filtrates from other filters dealing with pure phenol 
solutions, led to experiments being made on the separate effect of each of 
these organisms on phenol in solution. 
Colonies of the organisms in question were separated; the Tauern 
variety was usually grown on gelatine, the chromogenic organism in broth. 
Cultures were obtained from different sources—from the plates made in 
connection with the previous experiment, and from plates made from filtrates 
from different filters. Later, further cultures were obtained from plates 
showing colonies of only one organism. 
The culture medium used had the following composition :— 
Broth.— Per litre of water. 
BE DEOME Maron sateicosananvoes 10 grammes. 
Meat extract ............ Sor LO. 
