Levilactobacillus brevis

Levilactobacillus brevis is a gram-positive, rod shaped species of lactic acid bacteria which is heterofermentative, creating CO₂, lactic acid and acetic acid or ethanol during fermentation. L. brevis is the type species of the genus Levilactobacillus (previously L. brevis group), which comprises 24 species. It can be found in many different environments, such as fermented foods, and as normal microbiota. L. brevis is found in food such as sauerkraut and pickles. It is also one of the most common causes of beer spoilage. Ingestion has been shown to improve human immune function, and it has been patented several times. Normal gut microbiota L. brevis is found in human intestines, vagina, and feces.

L. brevis is one of the major lactobacilli found in tibicos grains, used to make kefir, but Lentilactobacillus species are responsible for the production of the polysaccharide (dextran and kefiran) that forms the grains. Major metabolites of L. brevis include lactic acid and ethanol. Strains of L. brevis and L. hilgardii have been found to produce the biogenic amines tyramine and phenylethylamine.