Lactobacillus plantarum

''Lactiplantibacillus plantarum'' (formerly ''Lactobacillus arabinosus'' and ''Lactobacillus plantarum'') is a widespread member of the genus ''Lactiplantibacillus'' and commonly found in many fermented food products as well as anaerobic plant matter. ''L. plantarum'' was first isolated from saliva. Based on its ability to temporarily persist in plants, the insect intestine and in the intestinal tract of vertebrate animals, it was designated as a nomadic organism. ''L. plantarum'' is Gram positive, bacilli shaped bacterium. ''L. plantarum'' cells are rods with rounded ends, straight, generally 0.9–1.2 μm wide and 3–8 μm long, occurring singly, in pairs or in short chains. ''L. plantarum'' has one of the largest genomes known among the lactic acid bacteria and is a very flexible and versatile species. It is estimated to grow between pH 3.4 and 8.8. ''Lactiplantibacillus plantarum'' can grow in the temperature range 12 °C to 40 °C. The viable counts of the "L. plantarum" stored at refrigerated condition (4 °C) remained high, while a considerable reduction in the counts was observed stored at room temperature (25 ± 1 °C).

Metabolism

''Lactiplantibacillus plantarum'' are homofermentative, aerotolerant Gram-positive bacteria that grow at , but not at , and produce both isomers of lactic acid ( D and L). Many lactobacilli including ''L. plantarum'' are unusual in that they can respire oxygen and express cytochromes if heme and menaquinone are present in the growth medium. In the absence of heme and menaquinone, oxygen is consumed by NADH-peroxidase with hydrogen peroxide as intermediate and water as end product. The peroxide, it is presumed, acts as a weapon to exclude competing bacteria from the food source. In place of the protective enzyme superoxide dismutase present in almost all other oxygen-tolerant cells, this organism accumulates millimolar quantities of manganese polyphosphate. Manganese is also used by ''L. plantarum'' in a pseudo-catalase to lower reactive oxygen levels. Because the chemistry by which manganese complexes protect the cells from oxygen damage is subverted by iron, these cells contain virtually no iron atoms; in contrast, a cell of ''Escherichia coli'' of comparable volume contains over one-million iron atoms. Because of this, ''L. plantarum'' cannot be used to create active enzymes that require a heme complex, such as true catalases.

''Lactiplantibacillus plantarum'', like many lactobacilli, can be cultured using MRS media.

Genomes

The genome sequencing of the lactic acid bacterium ''L. plantarum'' WCFS1 shows more molecular details. The chromosome contains 3,308,274 base pairs. The GC content of ''L. plantarum'' is 44.45% with the average protein count 3063. According to the experiment from Wageningen Centre for Food Sciences, the rRNA number of ''L. plantarum'' WCFS1 is 15, and the number or tRNA is 70.

Products

Silage

''Lactiplantibacillus plantarum'' is the most common bacterium used in silage inoculants. During the anaerobic conditions of ensilage, these organisms quickly dominate the microbial population, and, within 48 hours, they begin to produce lactic and acetic acids via the Embden-Meyerhof Pathway, further diminishing their competition. Under these conditions, ''L. plantarum'' strains producing high levels of heterologous proteins have been found to remain highly competitive. This quality could allow this species to be utilized as an effective biological pretreatment for lignocellulosic biomass.

Food products

''Lactiplantibacillus plantarum'' is commonly found in milk products, meat and a lot of vegetable fermentations including sauerkraut, pickles, brined olives, Korean kimchi, Nigerian Ogi, sourdough, and other fermented plant material, and also some cheeses, fermented sausages, and stockfish. The high levels of this organism in food also makes it an ideal candidate for the development of probiotics. In a 2008 study by Juana Frias et al., ''L. plantarum'' was applied to reduce the allergenicity of soy flour. The result showed that, compared to other microbes, ''L. plantarum''-fermented soy flour showed the highest reduction in IgE immunoreactivity (96–99%), depending upon the sensitivity of the plasma used. ''L. plantarum'' is also found in dadiah, a traditional fermented buffalo milk of the Minangkabau tribe, Indonesia.

''Lactobacillus plantarum'' strain K21 is a gram-positive bacteria isolated from fermented vegetables. It has the ability to hydrolyze bile salt when it is provided as a supplement. K21 also reduces the levels of cholesterol and triglyceride, and inhibits the accumulation of lipid in 3T3-L1 preadipocytes.
Furthermore, it reduces the level of plasma leptin, mitigates liver damage and alleviates glucose intolerance. Finally K21 inhibits body weight gain and fat mass accumulation.

Therapeutics

Because it is abundant, of human origin, and easy to grow, ''L. plantarum'' has been tested for health effects. It has been identified as a probiotic, which suggests its value for further research and application. ''L. plantarum'' has significant antioxidant activities and also helps to maintain intestinal permeability. It is able to suppress the growth of gas-producing bacteria in the intestines and may benefit some patients who suffer from IBS. It helps to create microbe balance and stabilize digestive enzyme patterns. ''Lactiplantibacillus plantarum'' has been found in experiments to increase hippocampal brain derived neurotrophic factor, which means ''L. plantarum'' may have a beneficial role in the treatment of depression. The ability of ''L. plantarum'' to survive in the human gastro-intestinal tract makes it a possible ''in vivo'' delivery vehicle for therapeutic compounds or proteins.

''Lactiplantibacillus plantarum'' is a constituent in VSL#3. This proprietary, standardized formulation of live bacteria may be used in combination with conventional therapies to treat ulcerative colitis and requires a prescription.

Antimicrobial property

The ability of ''L. plantarum'' to produce antimicrobial substances helps them survive in the gastrointestinal tract of humans. The antimicrobial substances produced have shown significant effect on Gram-positive and Gram-negative bacteria.

Activity against AIDS-defining illnesses

As a result of initial HIV infection, the gut has been found to be a prime center of immune activity.
* The immune systems' Paneth cells of the gut attack HIV by producing Interleukin 1 beta (IL-1β), which results in extensive collateral damage — sloughing of tight intestinal lining, witnessed as severe diarrhea. This destruction of the gut lining allows fungal pathogens to invade, e.g., ''Cryptococcus'' species, resulting in an AIDS-defining illness such as cryptococcosis, representing 60% to 70% of all AIDS-defining cases, but not necessarily only the gut. In rhesus macaques, ''L. plantarum'' is able to reduce (destroy) IL-1β, resolving inflammation, and accelerating gut repair within hours.

Biochemistry

The entire genome has recently been sequenced, and promoter libraries have been developed for both conditional and constitutive gene expression, adding to the utility of ''L. plantarum''. It is also commonly employed as the indicative organism in niacin bioassay experiments, in particular, AOAC International Official Method 944.13, as it is a niacin auxotroph.

See also

* Microbial food cultures
* ''Lactiplantibacillus plantarum'' strain PS128

References

Further reading

*

External links

*
www.DocGuide.com
another reference about IBS
Type strain of ''Lactobacillus plantarum'' at Bac''Dive'' - the Bacterial Diversity Metadatabase

{{Taxonbar, from=Q1756682

Digestive system
Probiotics
Lactobacillaceae
Bacteria used in dairy products
Bacteria described in 1923
Gram-positive bacteria