A COMPARATIVE STUDY OF MEMBERS OF THE LACTOBACILLUS GENUS, WITH SPECIAL EMPHASIS ON LACTOBACILLI OF SOIL AND GRAIN

Abstract

36 strains of lactobacilli, representing strains isolated from soil, grain, fecal material, milk products and dental caries, are described. Media used and methods of isolation are detailed. Fermentation reactions on 20 carbohydrates and related substances; action in milk, broth and gelatin; and acid production at 4 incubation temp., are listed. Agglutination reactions and complement-fixation tests of the 36 strains with antisera of representative strains are also listed, and results compared with fermentation reactions. Lactobacilli isolated from soil and grain did not as a rule ferment lactose. This marks them as a group distinct from L. acidophilus, L. bulgaricus, and L. odonto-lyticus. Of the lactose non-fermenters, 4 types are more or less definitely indicated on the basis of fermentation reactions.