Prebiotics and probiotics: choosing the right ingredient

The health of the gut microbiome has established itself as one of the most active pillars of nutraceutical research. And with this, the demand for pre- and probiotic ingredients has grown steadily in all markets.

But not all prebiotics and probiotics are the same. Choosing the right ingredient for a formula requires understanding their differences, their mechanisms of action and the criteria that determine their quality.

Definitions: probiotics, prebiotics and synbiotics

• Probioticslive micro-organisms which, when administered in adequate amounts, confer a health benefit to the host (WHO/FAO definition). These are mainly bacteria of the genera Lactobacillus, Bifidobacterium and Streptococcus, but also include yeasts such as Saccharomyces boulardii.
• Prebioticssubstrates used selectively by host micro-organisms that confer a health benefit (ISAPP definition 2017). They are mainly fermentable fibres such as inulin, FOS (fructooligosaccharides), GOS (galactooligosaccharides), pectins and resistant starch.
• Symbiotics: combinations of pre and probiotics that act synergistically, either because the prebiotic promotes the growth of the specific probiotic («synergistic symbiotic») or because the two act independently on the microbiome («complementary symbiotic»).

Key criteria for selecting a probiotic

• Specific strainThe efficacy of a probiotic is strain-specific, not genus-specific. Lactobacillus rhamnosus GG has very different evidence than generic Lactobacillus rhamnosus. It is essential to work with identified strains and associated clinical studies.
• CFU (Colony Forming Units)Effective dose varies per strain and per indication. CFU counts should be ensured at the end of the shelf life of the product, not only at the time of manufacture.
• Viability and stabilityProbiotics are living organisms and are sensitive to heat, moisture and acidity. Microencapsulation and freeze-drying technologies significantly improve survival during storage and gastrointestinal transit.
• Gastric resistanceto reach the large intestine alive, the micro-organisms must resist the acid pH of the stomach and bile salts. This parameter must be validated for each strain.

Key criteria for selecting a prebiotic

• SelectivityA good prebiotic should promote the growth of beneficial micro-organisms without indiscriminately stimulating the entire microbiota.
• Digestive toleranceat high doses, some prebiotics (especially FOS and inulin) may cause flatulence and discomfort. The choice of type and dose must balance efficacy and tolerance.
• Fermentation profileDifferent prebiotics produce different short-chain fatty acids (SCFA) when fermented. Butyrate, for example, is particularly relevant for colonocyte health.

Formulation applications

• Digestive and intestinal healthBifidobacterium + FOS/GOS, Lactobacillus acidophilus + inulin combinations.
• Immunity: strains such as Lactobacillus rhamnosus GG, Bifidobacterium longum, yeast beta-glucans.
• Mental health (gut-brain axis)Rapidly expanding line; strains such as Lactobacillus helveticus R0052 + Bifidobacterium longum R0175 with evidence on anxiety and mood.
• Child nutritionGOS, HMO (human milk oligosaccharides), Bifidobacterium breve.

In a nutshell

In today's market, the quality of pre- and probiotic ingredients is driven by strain specificity, guaranteed viability over the life of the product, and clinical evidence linked to the particular extract or strain. Making the right choice here is what differentiates a microbiome formula with real impact from one with marketing impact only.

At Sanmart we have a wide range of ingredients in this category, with GMP and ISO certifications and full traceability. Consult our catalogue or contact our technical team for more information.