FAMILY X. LACTOBACILLACEAE 



551 



Habitat: Widel}' distributed in fermenting 

 substances. 



14. Lactobacillus brevis (Orla-Jensen, 

 1919) Bergey et al., 1934. (Bacillus y, von 

 Freudenreich, Landw. Jahrb. d. Schweiz, 

 1891, 22; Bacillus casei y, von Freudenreich 

 and Thoni, Landw. Jahrb. d. Schweiz, 1904, 

 526; Beiabacterium breve Orla-Jensen, The 

 Lactic Acid Bacteria, 1919, 175; Bergey et 

 aL, Manual, 4th ed., 1934, 312.) 



bre'vis. L. adj. brevis short. 



Description supplemented by material 

 fromPederson (Jour, of Bact.,S5, 1938, 105). 



Rods, 0.7 to 1.0 by 2.0 to 4.0 microns, with 

 rounded ends, occurring singly, in short 

 chains and occasionally in long filaments 

 which may show granulation. Non-motile. 

 Gram-positive. 



Gelatin: No liquefaction. 



Agar slant: Growth, if any, faint. 



Broth: Turbid, clearing after a few daj^s. 



Milk: Acid produced but no clot except 

 with some freshly isolated strains. 



Does not attack casein as a rule. 



Utilizes calcium lactate as a source of 

 carbon. 



Acid from arabinose, xylose, glucose, 

 fructose, galactose and maltose. Strains 

 vary in fermentation of lactose, sucrose, 

 mannose and raffinose. Salicin, mannitol, 

 glycerol, rhamnose, dextrin, inulin and 

 starch seldom fermented. Usually shows a 

 particularly^ vigorous fermentation of arabi- 

 nose. 



Lactic acid produced usually optically 

 inactive; acetic acid, ethyl alcohol and 

 carbon dioxide formed in fermentation of 

 aldohexoses. Mannitol produced from fruc- 

 tose. Acetic and lactic acids produced from 

 the pentoses. 



Temperature relations: Optimum, 30° C. 

 Growth poor below 15° and above 37° C. 

 Maximum, 38° C. 



This species includes the large group of 

 gas-producing lactic acid rods ordinarily 

 characterized by a marked fermentation of 

 pentoses, particularly arabinose. Thej^ usu- 

 ally also ferment fructose more readily 

 than glucose. 



Comment: A chromogenic variety which 

 causes the production of rusty spot in cheese 

 has been described by Davis and Mattick 



(Proc. Soc. Agr. Bact., 1936, 3) and by Breed 

 and Pederson (Jour. Bact., S6, 1938, 667; 

 also see New York Agr. Exp. Sta. Tech. 

 Bull. 259, 1941, 15 pp.). 



Source: Isolated from milk, kefir, cheese, 

 feces, fermenting sauerkraut, ensilage, 

 manure, soils, sour dough and spoiled to- 

 mato products. 



Habitat: Widely distributed in nature, 

 particularly in plant and animal products. 



15. Lactobacillus fermenti Beijerinck, 

 1901. (Arch, n^erl. d. sci. exact, et nat., 

 Ser. 2, 7, 1901, 212.) 



fer.men'ti. L. neut.n. fermentum ferment 

 yeast; L. gen. noun fermenti of yeast. 



Description supplemented by material 

 from Smit (Ztschr. f. Garungsphysiol., 5, 

 1916, 273) and Pederson (Jour. Bact., 35, 

 1938, 106). 



Rods, variable in size, usually short (Bei- 

 jerinck), 0.5 to 1.0 by 3.0 to 15.0 microns 

 (Smit), sometimes in pairs or chains. Non- 

 motile. Gram-positive (Smit). 



Yeast extract-glucose-gelatin: Filiform, 

 no liquefaction (Pederson). 



Agar colonies: Flat, circular, small, trans- 

 lucent like droplets of water. 



Agar slant: Growth, if any, scant. 



Broth: Turbid, clearing after a few days. 



Milk: Unchanged or slightly acid. 



Reduction of litmus, methylene blue, 

 indigo carmine, sodium thiosulfate. NaoSOs 

 is reduced to H2S (Smit). 



Acid usually from glucose, fructose, malt- 

 ose, sucrose and lactose (Beijerinck) and 

 mannose, galactose and raffinose; some 

 strains ferment xylose; usually does not 

 ferment arabinose, rhamnose, sorbitol, 

 mannitol, inulin, dextrin, starch or salicin 

 (Pederson). 



Lactic acid produced usually optically 

 inactive; acetic acid, ethyl alcohol and 

 carbon dioxide are formed in the fermenta- 

 tion of aldohexoses (Smit), (Pederson). 

 Mannitol is formed in the fermentation of 

 fructose (Beijerinck), (Smit). Acetic acid 

 and lactic acid are produced from pentoses 

 if they are fermented (Pederson). 



These are the higher temperature gas- 



