Unlocking the Health Magic: The Remarkable Benefits of Non-Digestible Compounds

What Are Non-Digestible Compounds?

• Non-digestible compounds from plants comprise mainly complex carbohydrates such as pectin and hemicellulose. These compounds show variations in structure and composition, which exhibit both physicochemical properties and biological effects.

• The intestinal microbiota readily metabolizes the dietary fibers extracted from prebiotics. It mainly consists of a wide variety of bacteria, fungi, viruses, and other microorganisms present in the human digestive tract. These metabolized compounds lead to the formation of short-chain fatty acids (SCFAs). These SCFAs are the primary metabolites formulated by the large intestine’s microbiota through the anaerobic fermentation process involving indigestible polysaccharides such as dietary fiber and resistant starch. These non-digestible compounds provide anti-inflammatory and immunomodulatory properties to treat multiple pathological disorders.

What Are the Sources of Non-Digestible Compounds?

Natural Sources: Non-digestible carbohydrates are found in many natural sources like asparagus, sugar beet, garlic, grains, and onion.

Synthetic Methods: Commonly, non-digestible carbohydrates are synthesized by the following reactions:

1. Hydrolysis.
2. Isomerization.
3. Fructosyltransferase.

What Are the Uses of Non-Digestible Compounds?

1. The non-digestible compounds help in reducing blood cholesterol.

2. These compounds also improve the function of the large bowel.

3. The non-digestible carbohydrates are utilized as an energy source for the growth of probiotics established in the process of fermentation to facilitate the actions of the microbiota present. Thus it keeps the individual nourishing and healthy.

4. Prebiotics (non-digestible carbohydrates) also control obesity by the presentation of intestinal anorectic hormones (which control anorexic activities).

What Are the Health Benefits of Non-Digestible Compounds?

1. Effect on Hindgut Bacteria Composition: There are many beneficial properties of bacteria belonging to this genera.

2. Lactobacilli: It is responsible for downregulating mucosal inflammation in the gastrointestinal tract (downregulation is the process by which a cell reduces the quantity of a cellular component, like RNA (ribonucleic acid) or protein, in response to an outer stimulus). The following are the functions of lactobacilli:

• It helps in the digestion of lactose for lactose-intolerant individuals.
• Lactobacilli reduces constipation.
• It enhances irritable bowel syndrome (IBS) symptoms, like abdominal pain, bloating, diarrhea, and constipation.
• It helps in the prevention of traveler's diarrhea (a disorder of the digestive tract that commonly causes loose stools and abdominal cramps).

3. Bifidobacteria: It is found naturally in the gastrointestinal tract of healthy human adults and carries a vigorous affinity to ferment oligosaccharides (oligosaccharides represent carbohydrates that contain single sugar residues, such as raffinose, stachyose, and verbascose).

4. Metabolite Production: A primary metabolite is the one that is directly involved in normal growth, development, and reproduction. Secondary metabolites are organic compounds stimulated by any lifeform, such as bacteria, fungi, animals, or plants. These are not directly involved in the normal growth, development, and reproduction of the organism. These metabolites are known for providing health benefits in humans. Small-chain fatty acids having less than six carbons are formed by the gut microbiota by the fermentation of amino acids, carbohydrates, and other nutrients. These small-chain fatty acids are acetate, propionate, and butyrate formed mainly in the colon. Acetate helps in metabolizing energy for muscles. The fermentation of inulin-type fructans (a group of water-soluble, non-digestible, and fermentable carbohydrates belonging to prebiotics) boosts urinary hippurate concentrations. Hippurate is a co-metabolite found in lower concentrations in obese and diabetic individuals.

5. Effect on Mineral Absorption: For maintaining healthy bone structure in infants and elders, the main requirement is increased bioavailability and absorption of calcium along with sufficient intake of non-digestible compounds like prebiotics. The primary site of calcium absorption is the distal intestine. The chemical changes and increased acid fermentation promotes the absorption of calcium. Various clinical studies have been conducted to estimate mineral absorption in contrasting populations. Several factors such as the age and physiology of the individuals during puberty and after menopause show an increased affinity and need for calcium uptake.

6. Effect on Protein Fermentation: Protein fermentation usually takes place in the absence of fermentable carbohydrates directing to the formation and accumulation of potentially toxic metabolites like sulfides, amines, ammonia, and phenols. When there is an absence of fermentable carbohydrates, small-chain fatty acid concentration diminishes, and the pH of the habitat increases, which results in adequate conditions in the distal colon for protein fermentation, leading to the generation of branched-chain fatty acids and various phenols and indoles.

7. Change in Pathogenic Bacterial Populations: The fundamental components to function against pathogens (such as E. coli, Salmonella spp, Campylobacter, and other pathogenic bacteria) within the gastrointestinal tract are the gut mucosa and microbiota. The main five potential mechanisms are as follows:

• Acidic metabolic end products decrease the colonic pH below the thresholds of pathogenic bacteria.
• Competitive impacts due to restrictions in the number of colonization zones.
• Antagonism by inhibitory peptides created by lactic acid bacteria.
• Fixed nutrients.
• Boost the immune system.

8. Effect on Allergy Risk: The reduction in the levels of Bifidobacteria and Lactobacilli is accountable for the development of allergic infections in the initial five years of life. There are considerable mechanisms that demonstrate the significance of dietary oligosaccharides and their immune-modulating impacts. Fructo-oligosaccharides and gluco-oligosaccharides supplementation provide anti-allergic effects against the growth of eczema and rhinoconjunctivitis.

9. Effects on Gut Barrier Permeability: The gut barrier is formed by epithelial cells that line the mucosal surfaces in the body and provide protection against the outer surroundings. There are intestinal goblet cells that release mucin. Mucins form a hydrated gel that stops considerable particles from reaching the layer of epithelial cells. Small chain fatty acids induced by the fermentation of prebiotic dietary fiber help in improving intestinal barrier function. There are tight junctions that enable the barrier mechanisms present in the epithelial lining of the gastrointestinal tract. The tight junctions show convergence that leads to the formation of a ‘leaky gut’. These tight junctions are made up of several proteins, such as claudins, zonula occludens-1, and occludin get suppressed by high-fat accumulation in the body. Oligofructose stimulates particular microbiota change showing an increase in endogenous glucagon-like peptide-2 (GLP-2) production, therefore enhancing gut barrier functions and supplying tighter junctions.

10. Effects on Immune System Defense: There are many cells found in the gastrointestinal tract that play a crucial role in immune system response and signaling. TREG cells (regulatory T cells), effector T cells, natural killer cells, and B cells are all affected by prebiotics and the metabolites that are formed by their fermentation.

Conclusion

The non-digestible carbohydrates such as cereals, legumes, fruits, and vegetables are basically dietary fibers that can neither be digested nor absorbed by the small intestine of humans. The article reviews the various benefits of non-digestible compounds on gut bacteria production, gut barrier metabolism, allergic reactions, mineral absorption, protein fermentation, and the immune system.