GASTROINTESTINAL ECOLOGY: Probiotics and its Potential Benefits

1. GASTROINTESTINAL ECOLOGY:Probiotics and its Potential Benefits Manoj Kumar Food Technology

2. CONTENTS • Gastrointestinal Ecology • Probiotics • Prebiotics • Nutritional Aspects • Therapeutic Aspects

3. Gastrointestinal Tract Biologically Important Functions of Large Intestine • Storage • Excretion • Absorption • Secretion

4. Acquisition of gut flora in human infants Sterile FOETUS NEWBORN Predominating facultative anaerobes e.g. E.coli, Streptococci, Enterococci Highly reduced environment Dominated growth of obligatory anaerobes Established Gut microbial balance Inoculated by environment during birth Bifidobacterium, Bacteroides, Closteridium, Ruminococcus After weaning≥02 years of age

5. Composition of Gut Microflora • We have 10 times the amount of microbial cells than total other cells, with 500 types of microorganisms which mostly reside in our gut. Eukaryotic Cells≈1013 Human Body Prokaryotic Cells≈1014 Microorganisms ≈500 Genera with several hundred species of Bacteria

6. Intestinal Microflora: Location & Prevalence • Rare in the esophagus • Uncommon in the stomach • primarily Gram (+) • 102 – 104 • 105 in the jejunum – primarily aerobes • 1010 – 1012 in the colon • primarily anerobes • 1000x more anerobes than aerobes

7. There are up to 400-500 different bacterial species in the colon and the vast majority (99.9%) are strict anaerobes. Genus Non-sporing anaerobes Bacteriodes spp. Bifidobacterium spp. Eubacterium spp. Propionibacterium spp. Veillonella spp. Sporing anaerobes Clostridium spp. Sporing aerobes Bacillus spp. • Microaerophiles • Lactobacillus spp. • Streptococcus spp. • Enterococci • Facultative organisms • Coliforms • other Enterobacteria

8. FACTORS AFFECTING GUT MICROBIAL BALANCE • Abusive & improper dietary habits • Starvation • Alcohol consumption • Stress • Diseases of Intestinal Tract • Oral antibiotic therapy • Surgical Operations

9. Substrates for colonic bacterial growth • Resistant starch • Polysaccharides • Unabsorbed sugar-Lactose, Raffinose, Stachyose • Oligosaccharides-Fructo-oligosaccharides ( oligofructose, inulin) • Dietary and endogenous proteins (e.g. pancreatic enzymes) • Sugar alcohol- Sorbitol, Xylitol • Endogenous carbohydrates-Glycoproteins (e.g. mucin) • Other food additives

10. Major types of Metabolic Reactions • Synthesis of vitamins and amino acids. • Degradation of starch to simple sugars. • Fermentation of undigested polysaccharide to SCFA. • Degradation of proteins to AAs, amins & ammonia. • Hydrogenation of unsaturated fatty acids. • Transformation of primary to secondary bile acids. • Transformation of cholesterol to other sterols. • Reduction of nitrate to nitrite. • Detoxification e.g. bilirubin to urobilins. • Toxin production e.g. glycolysis of cycasin. • Carcinogen formation e.g. synthesis of N-nitroso compounds.

11. Generalized scheme of fermentation by human colonic microflora Dietary and Host produced substrates Polysaccharides Proteins and Peptides Monosaccharides Amino acids Bacterial Fermentation End Products Bacterial Mass H2S CH4 H2 CO2 SCFA Succinate Ethanol NH3 Amines BCFA Phenols/Indophenols Others Absorption and metabolism by the host or excretion in breath, feces & urine

12. PROBIOTICS: History and Concept 1907: Russian noble prize winner and father of modern immunology, Elie Metchnikoff, a scientist at the Pasteur institute, was the first conceptualize “probiotics”. • 1953: The term "probiotics" was first introduced by Werner Kollath to describe organic and inorganic food supplements applied to restore health to patients suffering from manlnutrition. (Hamilton-Miller et al., 2003)

13. 1965: Probiotic term was coined by Lilly and Stillwell. “Substances secreted by one organism which stimulate the growth of other’s”. • 1971: “Organisms and substances which contribute to intestinal microbial balance.” (Spriti,1971) • 1974: Parker defined the concept as, “Organisms and substances that have a beneficial effect on the host animal by contributing to its intestinal microbial balance”. • 1989: “Live microbial supplements which beneficially affects the host animal by improving microbial balance.” ( Fuller,1989)

14. 2001: “Live microorganisms which, when consumed in adequate amounts, confer a health benefit on the host”. (Food and Agricultural Organization / United Nations Organization / World Health Organization)

15. Characteristics of Effective Probiotics • Able to survive the passage through the digestive system. • Able to attach to the intestinal epithelia and colonize. • Able to maintain good viability. • Able to utilize the nutrients and substrates in a normal diet. • Non pathogenic and non toxic. • Capable of exerting a beneficial effect on the host. • Stability of desired characteristics during processing, storage and transportation. • Anti-inflammatory, antimutagenic, immunostimulatory.

16. Composition of Probiotics

17. More Probiotics… • Propionibacteriumfreudenreichii • Pediococcusacidilactici • Saccharomyces boulardii

18. PREBIOTICS • A prebiotic is a nondigestible food ingredient which beneficially affects the host by selectively stimulating the growth and/or activity of one or a limited number of colonic bacteria, thereby improving the health of the host .

19. Characteristics of Prebiotics • Should not be hydrolyzed or absorbed in the upper part of G.I tract. • Should be a selective substrate for one or a limited number of beneficial bacterial in colon. • Should be able to alter the colonic microflora in favour of healthier composition. • Should be able to induce beneficial systemic effects after absorption in the blood.

20. PROBIOTICS

21. Nutritional Aspects Synthesis of B-Vitamins Some bacteria including probiotics found in the gut produce vitamins. For example, they produce vitamin K (Cooke, 2006)folic acid, (Strozzi, 2008) and vitamin B12 (Molina, 2009).

22. Improved Digestibility Food Components Protein/Fat/Sugar Partial hydrolysis by enzymes elaborated by Probiotics Improved Digestibility

23. Anticholesterolaemic Effect • Endogenous/Synthesized • Exogenous/Absorbed Source of cholesterol Cholesterol Metabolism CH synthesis + Dietary CH = Faecal excretion of CH + Bile acids Cholesterol reduction Mechanism • Impaired CH synthesis • Reduced absorption of dietary CH • Stimulated catabolism of CH

24. Improved Lactose Utilization Lactose Malabsorption/Lactose Intolerance /Lactose Maldigestion Inability of a person to digest lactose adequately Flatulence Diarrhoea stomachae Production of H2 Lactose Fermentation by colon microflora Intestinal beta-galactosidase Absorption Glucose + Galactose Extra/intra cellular beta-galactosidase Lactic Acid + ETOH + CO2 Homolactic/Heterolactic fermentation

25. Therapeutic Aspects Antagonism • Growth inhibition of contaminating flora during fermentation process • Growth inhibition of harmful intestinal microflora after consumption of fermented products Metabolites Organic acids: Lactic acid, acetic acid, propionic acid Broad spectrum antagonists Hydrogen peroxide Diacetyle Bacteriocins

26. Antutimour Activities Bacteria in fermented milk Cancer: Set of Diseases, in which uncontrolled growth of cells takes place Digestion or autolysis Living Bacteria Bacterial cell components Stimulation or enhancement of immune system Inhibition of tumour cell Destruction of carcinogens Inhibition of microorganisms that may convert pro-carcinogens into carcinogens

27. Thank You A habit that can really benefits our overall health- “TAKING PROBIOTICS” Probiotics Revolution Begins