The 'Nomadic' Nature of Lactobacillus plantarum
Lactobacillus plantarum (now often referred to as Lactiplantibacillus plantarum following a taxonomic reclassification in 2020) is renowned for its hardiness and adaptability. This facultative anaerobic bacterium can thrive in both oxygen-rich and oxygen-poor environments and tolerate a wide range of temperatures and pH levels, from the acidity of the stomach to the bile-rich environment of the gut. This resilience allows it to colonize many different ecological niches, earning it the nickname of a 'nomadic' organism.
This robust nature is critical for its function as a probiotic, enabling it to survive the journey through the digestive system and colonize the intestinal tract. Its metabolic flexibility, which allows it to ferment a vast array of carbohydrates, further contributes to its ability to inhabit and adapt to diverse habitats, including many plant and food sources.
Fermented Foods: A Primary Source
One of the most common and accessible sources of Lactobacillus plantarum for humans is through the consumption of fermented foods. Its ability to produce lactic acid and other antimicrobial substances makes it a key player in many fermentation processes, helping to preserve foods and develop their characteristic flavors. These foods are often rich in live, active cultures of L. plantarum.
Fermented Vegetables
Fermented vegetables are a rich source of L. plantarum, where it helps create the sour, tangy taste and preserve the food. Examples include:
- Sauerkraut: Fermented cabbage where L. plantarum is a major species in the later stages of fermentation.
- Kimchi: A staple of Korean cuisine, this fermented cabbage dish is a well-documented source of L. plantarum strains.
- Pickles: Brined pickles rely on L. plantarum and other lactic acid bacteria to create a stable, acidic environment.
- Brined Olives: A traditional fermented food, particularly in the Mediterranean, with high concentrations of L. plantarum.
Fermented Dairy and Meats
While some Lactobacillus species are more common in dairy, L. plantarum can be found in some fermented animal products.
- Cheeses: Certain types of cheese contain L. plantarum, which can serve as a starter culture.
- Fermented Sausages: Specific strains are used as starter cultures in fermented sausages to aid preservation and flavor development.
- Dadiah: A traditional fermented buffalo milk product from Sumatra also hosts L. plantarum.
Grains and Sourdough
L. plantarum plays a vital role in the fermentation of many grain products, especially in traditional sourdoughs, where it interacts with other microbes to enhance flavor and texture. Recent studies even suggest that some L. plantarum strains can survive the baking process and become re-activated when stored.
Plants, Soil, and the Environment
Beyond fermented foods, Lactobacillus plantarum exists more broadly in nature. As its name suggests (plantarum is Latin for 'of the plants'), it is naturally present on raw plant matter. It can also be found in soil and on the surface of many plants where it contributes to their natural microbiome. This environmental presence means that it is often introduced into food products during the initial stages of fermentation.
The Human and Animal Microbiome
Lactobacillus plantarum is also a normal resident of the human and animal gastrointestinal tracts and other mucous membranes, such as the mouth. It is part of the transient microbiota, meaning it passes through and interacts with the native gut flora, but doesn't necessarily take up permanent residence. In this role, it helps maintain gut barrier function, competes with harmful bacteria, and can influence the immune system.
Natural vs. Supplement Sources
When considering your intake of Lactobacillus plantarum, it's important to understand the differences between consuming it through natural food sources versus probiotic supplements. Both can provide beneficial bacteria, but they differ in standardization and dosage.
| Feature | Natural Food Sources | Probiotic Supplements |
|---|---|---|
| Standardization | Not standardized; live culture counts and strains vary greatly depending on the product and preparation. | Standardized with a specific, guaranteed number of Colony-Forming Units (CFUs) and a defined strain(s). |
| Diversity | Often includes a complex mix of many different bacterial species and strains, creating a more diverse microbial input. | Typically contains one or a select few strains of L. plantarum specifically chosen for targeted health benefits. |
| Nutritional Matrix | The bacteria are delivered within a food matrix (e.g., fiber, vitamins) which provides additional nutritional benefits and can help protect the bacteria. | Delivered in capsules or powders, without the accompanying nutritional benefits of whole foods. |
| Preparation | Requires careful sourcing and sometimes specific storage conditions (e.g., unpasteurized and refrigerated) to ensure live cultures. | Shelf-stable preparations are common, but refrigeration may be required for some products. |
Conclusion
In summary, the sources of Lactobacillus plantarum are incredibly diverse, spanning from fermented foods that have been a part of human diets for millennia to the natural microbiomes of plants and animals. This versatile and hardy bacterium is widely available through a variety of vegetable, dairy, and grain fermentations, as well as in probiotic supplements. Its ability to tolerate harsh environments and ferment a wide array of carbohydrates has allowed it to become a prominent and beneficial inhabitant of many different ecological niches, including the human gut. Whether obtained through dietary choices or targeted supplements, the widespread presence of this organism is a testament to its important role in both food production and human health. For further reading on the science behind this bacterium, exploring academic resources like the NIH's PubMed database can provide more detail.
Key Takeaways
- Widespread Probiotic: Lactobacillus plantarum is a highly adaptable, 'nomadic' lactic acid bacterium with many different natural habitats.
- Fermented Food Staple: It is a core component of many fermented foods, including sauerkraut, kimchi, pickles, and sourdough bread.
- Natural Plant Colonizer: The bacterium is also found naturally on raw plant matter, contributing to fermentation when conditions are right.
- Human Microbiome Resident: L. plantarum is a part of the normal, though transient, flora of the human and animal gastrointestinal tracts.
- Resilient and Hardy: This species is known for its ability to survive a wide range of temperatures, pH levels, and bile salts, making it an effective probiotic.
FAQs
Question: Is Lactobacillus plantarum still called Lactobacillus? Answer: Following a taxonomic reclassification in 2020, Lactobacillus plantarum was renamed Lactiplantibacillus plantarum. However, many products and labels still use the older, more familiar name.
Question: What are the best food sources of Lactobacillus plantarum? Answer: Some of the best food sources include fermented vegetables like sauerkraut, kimchi, and pickles, as well as certain brined olives and sourdough products.
Question: Does Lactobacillus plantarum survive in sourdough bread after baking? Answer: Research suggests that while the heat of baking can inactivate L. plantarum, some strains may survive and become active again when the bread is stored. Baking does create beneficial postbiotic compounds.
Question: Can you get Lactobacillus plantarum from soil? Answer: Yes, the bacterium is present in soil and on raw plant matter. This environmental presence is often how it is introduced to foods during natural fermentation processes.
Question: Is there a difference between the L. plantarum in food and supplements? Answer: Yes. Food sources offer a non-standardized mix of bacteria in a whole-food matrix. Supplements provide specific, quantified strains often selected for particular health effects, but lack the whole-food benefits.
Question: Why is Lactobacillus plantarum so widely found? Answer: Its hardiness and metabolic flexibility allow it to tolerate a wide range of environmental conditions, including varying temperatures and acidity, enabling it to colonize many diverse ecological niches.
Question: Is L. plantarum always a probiotic? Answer: Not every strain of L. plantarum is considered a probiotic. For a strain to be classified as such, it must demonstrate a proven health benefit in adequate amounts, requiring specific testing and clinical validation.
