399 



Chemical Action of Bacillus lactis aerogenes (Escherich) on 

 Glucose and Mannitol : Production of 2 : 3-Butyleneglycol 

 and Acetylmethylcarbi nol . 



By Arthur Harden, D.Sc, Ph.D., and George Stanley "Walpole, B.Sc. 



(Melbourne). 



(Communicated by Dr. C. J. Martin, F.R.S. Received December 5, 1905, — 

 Read February 1, 1906.) 



(From the Chemical Laboratory, Lister Institute.) 



I. Action of B. lactis aerogenes on Glucose. 



In the course of an investigation on the chemical action on glucose of the 

 lactose-fermenting bacteria of faeces* it was found that, whereas B. coli 

 communis yields, with glucose, acetic acid and alcohol in approximately 

 equal molecular proportions, B. lactis aerogenes produces a much smaller 

 amount of acetic acid, relatively both to the alcohol and to the sugar 

 fermented. It was, moreover, previously known that B. lactis aerogenes 

 produces a greater volume of gas, containing a larger proportion of carbon 

 dioxide than does B. coli communis.] These facts indicate that the fermen- 

 tation of glucose by this organism is of a different type from that brought 

 about by the B. coli communis.% A detailed examination of the products 

 was therefore made. For this purpose the organism was grown anaerobically 

 in a medium containing 1 per cent, of Witte peptone and 2 per cent, of pure 

 glucose in the presence of chalk, the method of collecting the gases evolved 

 and of examining the products being the same as that previously employed 

 in the investigation of the action of B. coli communis on glucose.§ 



All the substances produced by B. coli communis from glucose were 

 again found, viz., lactic acid, acetic acid, succinic acid, formic acid, ethyl 

 alcohol, carbon dioxide, and hydrogen. A quantitative estimation, however, 

 revealed the fact that only about two-thirds of the carbon of the glucose was 

 thus accounted for. This is shown in the following tables, which embody 

 the results of three separate estimations (Cols. 1, 2, 3),- Table I giving the 

 actual percentages by weight on the sugar fermented of the various 

 substances produced, and Table II the number of carbon atoms per molecule 

 of sugar decomposed represented by each product. The results of a typical 

 * Harden, ' Journ. of Hygiene,' 1905, vol. 5, p. 488. 



+ Theobald Smith, 'Centralbl. f. Bakteriol.,' 1895, vol. 18, pp. 1, 494, 589. 

 % Harden, 'Trans. Cheni. Soe.,' 1901, p. 601. 

 § Harden, loc. cit. 



VOL. LXXVII. — B. 2 G 



