Probiotics are live microorganisms that when consumed in adequate amounts may provide health benefits. They include bacteria like Lactobacillus and Bifidobacterium. Probiotics can affect the intestinal flora, are promoted as food supplements, and have potential health claims, though many remain unproven. Prebiotics are nondigestible fibers that promote the growth of probiotic bacteria. Together, probiotics and prebiotics can modify the gut microflora and are thought to protect against pathogens and stimulate immune function, though their effects depend on the specific strains and more research is still needed to substantiate all claims.

1. PROBIOTICSDR SANGEETHA P

2. Functional foodsFunctional foods – substances or supplements administered to obtain a specific result in addition to basic nutrition. Also called “nutriceuticals” or “biotherapeutics”Examples:PrebioticsProbiotics

3. The concept of probioticsProbiotics (Greek) – “for life”WHO definition:Live microorganisms which, when administered in adequate amounts, confer a health benefit on the host

4. KEY POINTSLive micro organismsCan affect the intestinal floraPromoted as food supplementsHuge market potentialMany health claims…

5. History Fermented foods rich in probiotics are popular since prehistoric era eg: yoghurt,pickled vegetables..Metchnikoff – 1907 – yogurt with Lactobacilli prolongs lifeParker – 1974 – 1st to use the term probioticsFuller – 1989 – defined probiotics

6. Common organismsLactobacillusBifidobacillusSaccharomycescerevaciae..

7. Criteria for probiotics.Bacteria of human origin

8. Resist secretions of the upper GI tract

9. Survive passage through the GI tract

10. Adhere to human intestinal cells Criteria for probiotics.Able to colonize the intestine

11. Protect the cells against invasion by pathogens

12. Antagonize carcinogenic and pathogenic floraA few words about the gut microflora..Intesine is a main component of immune systemThe gut microflora is an important constituent in the intestine's defence barrier.Their number is 10 times the human cells..Have collective metabolic activity equal to a virtual extra organ !

13. The gut microflora

14. Symbiosis of gut floraSpecially adapted commensals..Beneficial to the hostStimulates immune functionProduces antimicrobial substancesTrophic effect on intestinal epitheliumMaintains the enterohepatic circulation Involved in metabolic processes (i.e., fermentation) in the colon

15. Factors affecting normal floraAny action taken to kill ‘bad’ bacteria essentially kills ‘good’ bacteria as well.

16. Antibiotics

17. Infections

18. Diet (highly processed, low-fiber foods)

19. Chronic diarrhea

20. Stress ..

21. Actions of probioticsRestore the balance b/w ‘Good’ and ‘bad’ bacteria in gutsecrete bactericidal proteins ↓ses the pHBlock the attachment & invasion of epithelium by pathogens

22. Improve epithelial barrier function ↑ mucus production ↑ barrier integrity