Lactobacillaceae

Lactobacillaceae is a family of Gram-positive, non-spore-forming bacteria within the order Lactobacillales. Members are lactic acid bacteria that primarily ferment sugars to lactic acid, a trait that underpins their widespread use in food fermentation and preservation. They are typically anaerobic or aerotolerant, and exhibit a range of morphologies from rods to cocci.

Taxonomically, Lactobacillaceae has grown more diverse in recent years as the former broad genus Lactobacillus was split into multiple genera. Today the family includes Lactobacillus sensu stricto and several related genera such as Lacticaseibacillus, Lactiplantibacillus, Limosilactobacillus, Levilactobacillus, and Ligilactobacillus. These changes reflect advances in genomic analysis and phylogenetic classification, while many species retain the common lactic acid-producing lifestyle.

Ecology and roles. Lactobacillaceae species inhabit a wide range of environments, including dairy products, fermented vegetables and meats, plant surfaces, and the gastrointestinal and vaginal tracts of humans and animals. They are key contributors to food fermentation, providing flavor, texture, and improved preservation. Some species are used as starter cultures or probiotics, aiming to support gut health or modulate the microbiome. They can be homofermentative, producing lactic acid as the sole product, or heterofermentative, generating lactic acid along with other metabolites such as ethanol, acetate, or CO2.

Safety and applications. Most Lactobacillaceae strains are considered safe for use in foods and dietary supplements, though rare cases of opportunistic infection have been reported. The family remains central to industrial biotechnology, nutrition, and food science due to its diverse metabolic capabilities and ecological ubiquity.