A prebiotic is a substrate that is selectively utilised by host microorganisms conferring a health benefit. In other words – prebiotic is a food source for beneficial microbes. 

Prebiotics positively influence the growth of beneficial bacteria like Lactobacilli and Bifidobacteria. Some examples include Inulin, Fructo-Oligosaccharide and Galacto-Oligosaccharide. 

Foods high in prebiotic fibre are garlic, chicory root, artichoke, leeks, asparagus and onions.

There is no consensus for a daily prebiotic recommendation however 3-8 grams per day is a common suggested dose. Some prebiotic fibres can cause side effects such as gas, bloating and abdominal cramping if used in high doses. The best way to minimise this is to start at the lowest dose and try introducing new prebiotic foods in small amounts; halve your prebiotic supplement dose or take it on alternate days.

We can think of plants as medicines – why? The potential medicinal effects of plant compounds isn’t new – several anti-cancer agents that are established therapies in the clinical setting are from botanicals. For example the Vinca alkaloids (vincristine, vinblastine) and the taxanes (paclitaxel) are two classes of compounds that are used as anti-cancer agents.

Polyphenols are secondary metabolites of plants which have evolved their own form of defence against environmental stressors like ultraviolet radiation, drought, salinity or aggression by plant pathogens. These polyphenols are abundant micronutrients in our plant-based diet and are present in fruits, vegetables, cereals, tea, coffee, dark chocolate and wine. There are several thousand different types of polyphenols with a structure of a phenol ring(s) with hydroxyl groups.

They are classified into different categories depending on the number of phenol rings and the different binding elements. They can also be associated with carbohydrates and or acids and with one another which increases the complexity of the group.

Polyphenols interact with the gut microbiota and influence human health through immunity, appetite, mood and energy metabolism. Polyphenols were originally thought to simply have antioxidant properties but further research suggests that they have both antibacterial and prebiotic properties.

The proposed prebiotic effects of polyphenols are believed to be through increasing nutrient processing, increasing gut mucus production and antimicrobial activities against pathogenic gut microbes. Polyphenols feed gut microbes.

Possible mechanisms for the health benefits of dietary polyphenols

• More favourable gut microbiota composition, e.g. an increase in beneficial keystone species like Akkermansia muciniphila and Faecalibacterium prauznitzii
• Increased production of gut microbiota metabolites like SCFA
• Inhibition of pathogenic bacterial cell growth through cell membrane interference
• Biotransformation of polyphenols by gut microbes results in increased bioavailability

Bio-availability of polyphenols remains low. They are generally not free floating are often bound to protein and fibre. The variability of polyphenol content in foods is influenced by a multitude of factors like the microclimate, method of harvest, storage and culinary preparation. The concentrations of these compounds in the plasma are extremely low. The total polyphenol intake probably commonly reaches 1 g/day in people who eat several servings of fruit and vegetables per day. 

Postbiotics can be described as a preparation that can include 

• Inanimate or non-viable microbes (they have been deactivated) and/or
• Microbial cell components like cell walls and cell surface proteins with or without
• Microbial metabolites or by-products – these include enzymes, peptides, polysaccharides, cell surface proteins and may be used to promote health directly or indirectly.

The postbiotic B. lactis is a deactivated form of the probiotic B. lactis. This is done by a precise heat-inactivation process, resulting in retention of the integrity of the microbe and its metabolites.

The postbiotic components include B.lactis, L.plantarum and short chain fatty acids (SCFA). Examples of SCFA are lactate, acetate, butyrate, propionate. These important molecules are emerging as health compounds in their own right. They generally result from fibre fermentation by the gut microbiota, and play a significant role in maintaining gut barrier health and modifying inflammation. 

Bifidobacterium species fulfill important functions within the human colon. They interact with other colon bacteria such as butyrate producing bacteria by cross-feeding interactions. Both Bifidobacteria and butyrate producers are needed and the most prevalent approach to cause bifidogenic and butyrogenic effects involve the consumption of probiotics and prebiotics.

Butyrate – is an essential metabolite in the colon and

• is the preferred energy source for colon epithelial cells
• contributes to the maintenance of the gut barrier
• has immunomodulatory and anti-inflammatory properties

We use active fluorescent units (AFUs) and total fluorescent units (TFUs) to measure the number of viable and non-viable bacterial cells in the product including the probiotic species and postbiotics. This quantification method utilises image cytometry to separate a microbial population into live, damaged and dead cells. Fluorescently labelled cells are interrogated by a laser to excite the dyes that stain live or dead cells, advanced software is used to differentiate viable and non-viable cells in seconds to provide accurate counts in contrast to traditional microbial counting methods.