Acetic acid Bacteria Ethanol utilization

Propionic acid bacteria can use citrate as a carbon source. In the presence of lactate the utilization of citrate is suppressed (Hietaranta and Antila, 1954). Propionibacteria can oxidize acetate and propionate. The oxidation is intensified in the presence of thiamine, Mg and ions displaying synergistic actions (Quastel and Webley, 1942). In the absence of thiamine Mg and stimulate the oxidation of succinate, fumarate, lactate, ethanol, propanol, and glucose. It has been suggested (Quastel and Webley, 1942) that enhanced the effect of Mg by increasing the permeability to the latter. 

Chemical hydrolysis or solvolysis is the only method available at present to remove sulfate groups from bile acids. It is known that some colonic bacteria possess a sulfatase which can utilize sulfated bile acids as substrate (H24), but this enzyme has not yet been purified. The position of the sulfate moiety in monosulfated bile acids is nearly always at C-3 and this group is easily removed by acid hydrolysis in ethereal solution after removal of glycine or taurine (VI). This method, however, does not remove sulfate groups from C-7 or C-12 (PI). For complete removal, other methods have been described, including solvolysis in acidified methanol-acetone for 18 hours at 37°C (P6), acidified ethyl acetate-ethanol for 16 hours at 39 C (A6), or acidified 2,2-dimethoxypropane for 12 hours at room temperature (C3). 

---