- Literally milk bacteria, normally found in the mouth, intestinal tract, and vagina. Lactobacillus can also live in fermenting products, such as yogurt. Humans appear to have a symbiotic relationship with this bacteria: it’s been with us so long that some types have become an important part of food digestion, although it can also contribute to cavities in the teeth if allowed to remain too long within the mouth.
* * *A genus of microaerophilic or anaerobic, nonsporeforming, ordinarily nonmotile bacteria (family Lactobacillaceae) containing Gram-positive curved or straight rods that vary from long and slender cells to short coccobacilli; chains are commonly produced especially in the later part of the logarithmic phase of growth. These organisms possess complex nutritional requirements, generally characteristic for each species; metabolism is fermentative and at least half of the end product is lactic acid. They are found in dairy products, effluents of grain and meat products, water, sewage, beer, wine, fruits and fruit juices, pickled vegetables, and in sourdough and mash, and are part of the normal flora of the mouth, intestinal tract, and vagina of many warm-blooded animals, including humans; as normal flora, they produce bacterocidins protective against pathogenic bacteria; rarely are they pathogenic. The type species is L. delbrueckii. [lacto- + bacillus]- L. acidophilus a bacterial species found in the feces of milk-fed infants and also in the feces of older persons on a high milk-, lactose-, or dextrin-containing diet.- L. brevis a bacterial species widely distributed in nature, especially in plant and animal products; it is also found in the mouth and intestinal tract of humans and rats.- L. catenaformis an anaerobic bacterial species found in the intestines and pulmonary cavities of humans.- L. curvatus a bacterial species found in cow dung, dairy barn air, silage, milk, and in a case of endocarditis.- L. delbrueckii a bacterial species found in fermenting vegetables and grain mashes; it is the type species of the genus L..- L. fermentum a bacterial species found widely distributed in nature, especially in fermenting plant and animal products. Also found in the mouth of human beings.- L. jensenii a bacterial species isolated from human sources such as vaginal discharge and blood clot.- L. plantarum a bacterial species found in dairy products and environments, fermenting plants, silage, sauerkraut, pickled vegetables, spoiled tomato products, sour dough, cow dung, and the human mouth, intestinal tract, and stools.- L. salivarius a bacterial species found in the mouth and intestinal tract of the hamster, the mouth of humans, and the intestinal tract of the hen.- L. trichodes a bacterial species found in wines containing 20% ethanol and in lees in California, Australia, France, and Spain; in California this organism is commonly referred to as the hair bacillus, cottony bacillus, cottony mold, or Fresno mold.
* * *lac·to·ba·cil·lus .lak-tō-bə-'sil-əs n1) cap a genus of gram-positive nonmotile lactic-acid-forming bacteria of the family Lactobacillaceae including various commercially important lactic acid bacteria2) pl -li -.īalso -.ē any bacterium of the genus Lactobacillus
* * *n.a genus of Gram-positive nonmotile rodlike bacteria capable of growth in acid media and of producing lactic acid from the fermentation of carbohydrates. They are found in fermenting animal and plant products, especially dairy products, and in the alimentary tract and vagina. They are responsible for the souring of milk. The species L. acidophilus is found in milk and is associated with dental caries. It occurs in very high numbers in the faeces of breast- or bottle-fed infants.
* * *Lac·to·bac·il·lus (lak″to-bə-silґəs) [lacto- + L. bacillus small rod] a genus of bacteria of the family Lactobacillaceae, occurring as large, gram-positive, asporogenous, rod-shaped organisms. They are anaerobic or microaerophilic and occur widely in nature and in the human mouth, vagina, and intestinal tract. In the oral cavity, they are found associated with dental caries but have no known etiologic role. They are separable into two groups, the homofermentative group producing only lactic acid, and the heterofermentative group producing other end products of fermentation.
Medical dictionary. 2011.