ingredient information
L Brevis
AAA
Lactobacilli are characterized as Gram-positive, nonsporeforming rods. They are catalase-negative when grown without blood and are nonmotile. They do not usually reduce nitrate and they utilize glucose fermentatively (Kandler and Weiss, 1986). The genus Lactobacillus presently comprises more than 50 recognized species of non pathogenic bacteria which are useful to human in several respects: they are indispensable agents for the fermentation of foods and feed, and they exert probiotic effects in human and animals. Lactobacillus brevis is an heterofermentative bacterium that utilizes hexoses by the 6-phosphogluconate pathway, producing lactic acid, CO2 and ethanol and/or acetic acid in equimolar amounts (Kandler, 1983). It can be isolated from many different environments and it is frequently used as starter culture in silage fermentation, sourdough and lactic-acid-fermented types of beer. In beverages obtained by alcoholic fermentation, lactobacilli may contribute to the quality of the product but may also cause spoilage. Certain L. brevis strains are resistant to hop bittering substances such as isohumulone and are able to grow in beer. Their growth changes the turbidity, flavor and aroma of the beer (Richards and Macrae, 1964). L. brevis strains involved in wine fermentation may produce biogenic amines by decarboxylation of the precursor amino acids through the action of substrate-specific enzymes. The ingestion of foods containing high levels of such amines, particularly histamine and tyramine, can lead to several toxicological disturbances (ten Brink et al., 1990; Mariné-Font et al., 1995). http://genome.jgi-psf.org/lacbr/lacbr.home.html