Lactobacillus delbrueckii subsp. bulgaricus

(Redirected from Lactobacillus bulgaricus)
Jump to: navigation, search
Lactobacillus bulgaricus
Scientific classification
Kingdom: Bacteria
Division: Firmicutes
Class: Bacilli
Order: Lactobacillales
Family: Lactobacillaceae
Genus: Lactobacillus
Species: L. delbrueckii
Subspecies: bulgaricus
Binomial name
Lactobacillus delbrueckii subsp. bulgaricus
(Orla-Jensen 1919)
Rogosa & Hansen 1971
Weiss et al. 1984 (subspecies status)


Lactobacillus bulgaricus (binomial name Lactobacillus delbrueckii subsp. bulgaricus) is one of several bacteria used for the production of yogurt. First identified in 1905 by the Bulgarian doctor Stamen Grigorov, it is named after Bulgaria. Morphologically, it is a Gram-positive rod that may appear long and filamentous. It is also non-motile, and it does not form spores. It has complex nutritional requirements, including the inability to ferment any sugar except for lactose. This bacterium is also regarded as aciduric or acidphilic, due to the fact that it requires a relatively low pH (around 5.4-4.6) in order to grow effectively.

The bacterium feeds on milk and produces lactic acid which also helps to preserve the milk. It breaks down lactose and is often helpful to sufferers of lactose intolerance, whose digestive systems lack the enzymes to break down lactose to simpler sugars. While fermenting milk, Lactobacillus bulgaricus produces acetaldehyde, which perfumes yogurt. Some of the biggest importers of the bacterium are Japan, USA and the EU.


  • A. Balows, H.G.Truper, M. Dworkin, W. Harder, K.H.Schleifer (1991). The Prokaryotes, 2nd Edition, A Handbook on the Biology of Bacteria, Chapter 70, pg 1547.

External links

bg:Lactobacillus bulgaricus de:Lactobacillus delbrueckii subspecies bulgaricus hu:Lactobacillus bulgaricus fi:Lactobacillus bulgaricus