Abstract
Ochoa isolated from Lactobacillus arabinosus an enzyme capable of bringing about the transformation of malic acid into lactic acid and carbonic acid gas, so that the problem of biological acid degradation appears in a new light. These researches are of course to be made also for acid degrading (malo-lactic) bacteria, yet certain base lines are established for them. Likewise, there is known from the work of Charpentie, Ribereau-Gayon and Peynaud, the probable mechanism of citric acid fermentation by the same bacteria. The method, derived from that of Langueron-Guerra allows more observations in relation to the importance of various factors for the acid degradation. For control of the biological fermentation paper chromatography is of great importance, as the experiments by J. and P. Ribereau-Gayon show.