Lactobacillus Taxonomy

Lactobacillus Taxonomy

NEW name for some probiotics! What you need to know.

In April 2020, the International Journal of Systematic and Evolutionary Microbiology (IJSEM) published a change in how Lactobacillus is classified. Lactobacillus is a very common and popular “friendly” bacteria used as a live microbial dietary ingredient (LMDI) and probiotic that is often found in fermented foods, like yogurt, and in dietary supplements. Prior to the IJSEM announcement, Lactobacillus was comprised of 261 species that have now been reclassified into 25 genera. When reading the name of a LMDI and probiotic, the genus comes first followed by species and strain. For example, Lactobacillus (genus) rhamnosus (species) GG(strain) is a popular strain of bacteria used in dietary supplements.

The choice to make this change was due to the genetic sequence data that suggested the genus Lactobacillus was too broad genetically. The change helps keep the LMDI and probiotic groups more accurate and organized. Only the genus name “Lactobacillus” has changed, not species or strains that are found in the LMDI and probiotic name.

What is changing? The microorganisms used as food cultures and probiotics in your food or dietary supplement will not change, but the label might. This is dependent on the U.S. Food and Drug Administration (FDA) deciding to mandate changes.

Old NameNew NameAbbreviated Name
Lactobacillus caseiLacticaseibacillus caseiL. casei
Lactobacillus paracaseiLacticaseibacillus paracaseiL. paracasei
Lactobacillus rhamnosusLacticaseibacillus rhamnosusL. rhamnosus
Lactobacillus plantarumLactiplantibacillus plantarumL. plantarum
Lactobacillus brevisLevilactobacillus brevisL. brevis
Lactobacillus salivariusLigilactobacillus salivariusL. salivarius
Lactobacillus fermentumLimosilactobacillus fermentumL. fermentum
Lactobacillus reuteriLimosilactobacillus reuteriL. reuteri

What is not changing? The following Lactobacillus names will not change:

  • Lactobacillus acidophilus
  • Lactobacillus gasseri
  • Lactobacillus helveticus
  • Lactobacillus bulgaricus

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