Bacteria in the gut microbiota – and lactic acid bacterial function

Beneficial and less favourable bacteria in the gut microbiota

Bacteria long held a negative reputation, primarily associated with disease and infection. Today, however, it is established that the human body is inhabited by vast numbers of bacteria, the majority of which are beneficial. These populations exist on the skin, in the urogenital tract, and within the respiratory system. A significant proportion of the body’s bacteria is located in the gastrointestinal tract, housing approximately 100 trillion bacteria that collectively constitute the gut microbiota.

Bacteria are classified into various types, including different species and strains. It is common to distinguish between beneficial and less favourable bacteria, alongside neutral bacteria that, while neither beneficial nor harmful, play a role in digestion. Each bacterium possesses unique properties and functions, typically categorised across three levels: genus, species, and strain. Differences at the strain level are critical, as different strains within the same species can exhibit distinct biological properties and effects within the body. The highest level is the genus, such as Lactobacillus, which is frequently utilised in probiotic and synbiotic supplements.

The influence of gut microbiota on systemic inflammation

Neglecting gut health can allow less favourable bacteria to proliferate, potentially leading to dysbiosis—an imbalance in the gut microbiota. Dysbiosis can, in turn, influence inflammatory processes in the body. Over time, prolonged inflammation is linked to various health challenges. To mitigate and prevent chronic inflammation, it is necessary to balance and maintain a functional gut microbiota. This can be achieved through a nutrient-dense, high-fibre diet, physical activity, stress management, and the administration of lactic acid bacteria and fibres that support the microbiota.

In recent decades, research into the gut microbiota has identified specific bacterial strains that have been studied extensively in relation to the intestinal barrier, inflammation, and immune regulation.

Lactic acid bacteria and other beneficial microorganisms

Lactic acid bacteria are a type of beneficial bacteria common in probiotic supplements and fermented foods. Despite the name, lactic acid bacteria are unrelated to dairy; they are named for their ability to ferment sugars into lactic acid. In the intestines, these bacteria help inhibit less favourable bacteria by producing lactic acid, creating an inhospitable environment for transient or harmful microorganisms.

Lactic acid bacteria occur naturally in certain foods, such as fermented vegetables. However, many individuals choose to complement their intake with probiotic or synbiotic supplements. The combination of lactic acid bacteria and fibres is termed synbiotics, aiming to enhance the conditions for bacterial survival and activity in the gut. For individuals seeking to support their gut microbiota, a synbiotic supplement can serve as a valuable technical complement.

There are numerous strains of lactic acid bacteria, yet they do not all share the same properties. It is essential that manufacturers validate bacterial strains through clinical trials involving human subjects. Two strains frequently utilised in probiotic preparations are Lactobacillus plantarum and Lactobacillus paracasei, both of which are included in Synbiotic.

The composition of lactic acid bacteria

Certain probiotic supplements combine multiple bacterial strains without clinical evidence regarding how these strains interact. When combining strains, there is a risk of competitive inhibition, where bacteria counteract each other’s effects. Consequently, it is vital that clinical studies are conducted on the final formulation rather than solely on individual strains.

Furthermore, many supplements on the market contain identical bacterial strains. In some instances, the same bacteria are found in different products at varying price points. The specific combination of bacterial strains in Synbiotic is the result of years of research. These strains are patented and unique, and cannot be found in any other supplement.

This extensive research foundation is a distinguishing feature of Synbiotic. In 1999, a research group led by Professor Stig Bengmark began identifying an anti-inflammatory selection of lactic acid bacteria. They examined over 500 different lactic acid bacteria before selecting the most effective anti-inflammatory strains. These strains were chosen for their ability to interact synergistically. The selected strains were then combined with four types of dietary fibres designed to support bacterial growth and colonisation.

Synbiotic 2000

The composition was patented under the name Synbiotic 2000. Since then, this research preparation has been utilised in numerous studies at prestigious hospitals and universities worldwide. The results have demonstrated that Synbiotic 2000 is effective in modulating inflammation, reconditioning the gut microbiota, and strengthening the immune system.

In recent years, research has also identified correlations between gut health and neurological conditions, highlighting the gut-brain axis. Findings indicate psychological effects of lactic acid bacteria, showing they may support emotional regulation and contribute to cognitive improvements, including enhanced attention, focus, and reduced hyperactivity.

Synbiotic contains five strains across four genera: Bifidobacterium breve, Pediococcus pentosaceus, Lactobacillus casei ssp. paracasei, Lactobacillus plantarum, and Leuconostoc mesenteroides.

Is a higher number of bacterial strains preferable?

A higher number of strains is not necessarily superior. While preparations containing numerous strains may seem advantageous in theory—given the thousands of species in the human gut—the quantity of strains or the total bacterial count does not solely determine efficacy. The critical factor is which specific strains are used and whether their effects are documented in clinical trials.

Lactic acid bacteria are living organisms that interact with their environment. Different strains vary in their compatibility; some enhance each other’s properties, while others may compete. For a supplement to maintain high quality, both the individual effects of the strains and their synergy must be thoroughly researched. The clinical evidence supporting the entire combination of bacteria and ingredients is more significant than the total number of bacteria or strains.

Survival of lactic acid bacteria during gastrointestinal transit

The journey through the gastrointestinal tract is challenging, as bacteria must survive exposure to gastric acid and bile salts. Studies indicate that not all lactic acid bacteria survive this passage. The strains utilised in Synbiotic have demonstrated high resistance to both bile salts and low pH levels, ensuring their ability to reach the colon. An advantage of synbiotics is that the included fibres provide nutrition for the bacteria during transit. Independent studies have recovered the specific strains found in Synbiotic in the faecal matter of subjects, confirming successful passage through the digestive system.

Storage for bacterial viability

Supplements containing lactic acid bacteria should be stored in a refrigerator to ensure optimal survival. Storage at room temperature results in a decline of active bacteria over time. To ensure the bacterial concentration in our supplements, we conduct regular stability testing. We monitor our products continuously in both refrigerated and room-temperature conditions to ensure they withstand transit to the consumer. While we recommend refrigerated storage for Synbiotic, the product remains stable during shorter periods at room temperature, such as during delivery.

Key considerations when selecting a supplement

• Ensure that bacteria and fibres are combined (synbiotics) to optimise bacterial activity in the gut.

• Verify that the specific preparation has been evaluated in clinical trials.

• Confirm that the interaction of the combined bacteria is scientifically validated.