Lactobacillus plantarum

Genus/species (aliases):  Lactobacillus plantarum

Gram Stain: Positive

Morphology:

Cell:  small (0.5 – 1.2 x 1.0 – 10μm), elongated rod-like bacilli assembled in pairs or in chains of variable length

Colony:  punctiform, convex, entire margin                 
Liquid Growth: dispersed 



Physiological Traits:

  • Facultative hetero-fermenters and facultative anaerobes
  • Substrates:  malic acid, tartaric acid, glucose, and some pentose sugars
  • Products:  mostly lactic acid, but also acetic acid, succinic acid, ethanol, carbon dioxide, biogenic amines, and precursors of ethyl carbamate


Ecological Traits:

  • Can be found in a variety of different plants (“plantarum” means species of the plants), and is used for fermentations in meat and cabage and in cheese and yogurt production
  • Present in the GI tract of humans and animals and considered a probiotic because of its ability to inhibit growth of harmful bacteria


Distinguishing Features:

  • (G+C)%:  36-47%
  • Catalase negative
  • DNA composition specific to organism and is not influenced by culture conditions, therefore genomic identification is highly reliable
  • API 50 CHL identification system can be used, as it is known to grow on 25 of the 49 substrates


Role in wine:

  • This organism is commonly present in grapes, plant material and musts, but is also found in wine.  It can also be present in a variety of winery surfaces.
  • Spoilage by this organism is common in musts and wine, and is caused by its hetero-fermentative property of converting malic acid into compounds other than lactic acid.  Of these, acetic acid is of concern and biogenic amines and ethyl carbamate may be produced.


Sensitivities: 

SO2: slight

Sorbate:

DMDC: yes

pH: slight

Acids:

Ethanol: Slight

Anaerobiosis:

Heat