Probiotics are live microorganisms which provide health benefits when consumed, generally by improving or restoring the gut flora. Probiotics can be formulated into many different types of products like foods, drugs, and dietary supplements. Species of Lactobacillus and Bifidobacterium are most commonly used as Probiotics, but the yeast Saccharomyces Cerevisiae and some E. coli and Bacillus species are also used as Probiotics. In order to provide health benefits in host, the quantity of microorganisms present in probiotic products should be around 105 to 107 cfu/ml (colony forming units per milligram).
Human gut (small intestine + large intestine) contains enumerous amount of bacteria which helps in digesting food, absorption of nutrients from foods and also acts against several harmful environmental factors by improving immunity. About 80% of our immune system is found in the gut. Much like genetic imprint of an individual has a unique microbiota, though approximately one-third of the species are common across most humans. Many factors influence intestinal microbiota including hygiene, diet, geographical location and host genotype.
The World Health Organization defines Probiotics as
“Live microorganisms which, when administered in adequate amounts, confer a health benefit on the host”
It is a condition where there is an imbalance between the types of organisms present in a person’s natural microbiota, especially in gut, thought to contribute to a range of conditions of ill health. The main symptoms of Dysbiosis are digestive disturbances and may also experience bloating, abdominal crampings, diarrhea, and constipation. common causes of Dysbiosis is antibiotic therapy, Autoimmune conditions , IBD and others are fast paced lifestyle, stress, food habits, Alcohol intake and cigarette smoking. Prebiotics are known to restore that balance of good bacteria and improve gut health.
The concept of Probiotics was first introduced by Elie Metchnikoff (father of probiotics). He hypothesised that consuming large amounts of fermented milk products that contained lactobacillus bacteria could prolong and improve the quality of life. He suggested that “intestinal auto-intoxication” could be suppressed by modifying the gut microbiota and replacing proteolytic microbes such as Clostridium—which produce toxic substances including phenols, indoles, and ammonia from the digestion of proteins—with useful microbes. He developed a diet with milk fermented with the bacterium he called “Bulgarian bacillus”.
The term “Probiotics” was first introduced in 1965 by Lilly and Stillwell; in contrast to antibiotics, Probiotics were defined as microbially derived factors that stimulate the growth of other organisms. The word “probiotic” comes from the Greek word pro meaning “promoting” and biotic, meaning “life”.
EXAMPLES OF FOODS CONTAINING PROBIOTICS
Yogurt - lactobacillus bulgaricus and streptococcus thermophilus.
Curd - lactobacillus acidophilus, lactococcus lactis etc.
Kefir - lactobacillus kefiranofaciens, lactobacillus helveticus, lactobacillus bulgaricus and streptococcus thermophilus.
Kombucha – acetic acid bacteria and osmophilic yeast.
Sauerkraut - leuconostoc mesenteroids, lactobacillus brevis, pediococcus pentosaceus and lactobacillus plantarum.
Kimchi – leuconostoc mesenteroids, leuconostoc pseudomesenteroides, lactococcus lactis, lactobacillus bravis and lactobacillus plantarum.
Tempeh – rhizopus oligosporus or rhizopus oryzae and firmicutes.
Acidophilus milk – lactobacillus acidophillus.
Sake – aspergillus oryzae and saccharomyces cerevisiae.
HEALTH BENEFITS OF PROBIOTICS
- Diarrhea: Increase in the frequency of bowel movements can be cured and prevented by consuming Probiotics.
- Irritable Bowel Syndrome(IBS): Reason for this disease is still unknown. a diagnosis is made based on symptoms(stomach bloating and pain). IBS can be prevented by the Lactobacillus plantarum 299V.
- Helicobacteriosis: It is a bacterial infection caused by Helicobacter pylori that causes inflammation of the lining of the stomach. Probiotic has an in vitro inhibitory effect in reducing gastric inflammation.
- Necrotizing enterocolitis: It is a serious intestinal disease among premature babies. It happens when tissue in the intestine is injured or inflamated. Treating with Bacillus infantis and Lactobacillus acidophilus to new born result in reduction of NEC.
- Urogential infection: An infection in any part of the urinary systems, the kidneys, bladder or urethra can be prevented by taking Lactobacillus fermentum and Lactobacillus rhamnosus.
- Colon cancer: Lactic bacteria may act against cancer of the colon or rectum, located at the digestive tracts lower end.
- Blood pressure: Milk fermented by lactic acid bacteria may result in the reduction of this sickness.
MECHANISM OF ACTION
- Bioconversion - It is the process of converting complex compounds into simpler ones, which helps in easy digestion and facilitates nutrition absorption for example, sugars into fermentation products
- Production of growth substrates - Probiotics produces growth substrates like vitamins B and K, which help other useful bacteria in its growth and activity.
- Direct antagonism - Probiotics produces antimicrobial substances like hydrogen peroxide, organic acids, Bacteriocin, acidophilin etc which is responsible for the death of harmful bacteria.
- Competitive exclusion - Probiotics binds itselves to the binding sites exerting competition to harmful bacteria for binding sites
- Improved barrier function - It makes intestinal walls impermeable for harmful bacteria and the toxins produced by them
- Production of β- D- galactosidase enzymes - In case of lactose intolerant people who are incapable to digest lactose because of the absence of lactase enzymes, these probiotics produces β- D- galactosidase enzymes that act as alternative and helps in breaking down lactose.
- Reduction of inflammation - By altering intestinal properties, probiotics help in reducing inflammation
- Stimulation of innate immune response
PROPERTIES OF PROBIOTICS
- It should be safe to the host.
- It should not produce any pathogenic or toxic effect.
- It must be resistance to hydrochloric acid, bile and pancreatic juice.
- It should have anti-carcinogenic activity.
- It should retain viability during storage and use.
- It should stimulate the immune system of the body.
- It should have the ability to colonize the gastrointestinal tract.
COMMON STRAINS OF PROBIOTICS
- Lactobacillus species
- Bifidobacterium species
- Bacillus cereus
- Non pathogenic Escherichia coli
- Saccharomyces cerevisiae (yeast)
- Enterococcus faecalis
- Streptococcus thermophilus etc
INSTITUTES ENGAGED IN PROBIOTIC RESEARCH IN INDIA
- Central Food Technology And Research Institute, Mysore, India
- National dairy research institute, Karnal, Haryana, India
- Institute of microbial technology, Chandigarh, India
- National dairy development board, Anand, Gujarat,India
- Nestle Pvt Ltd, Panipat, Haryana, India
ARE PROBIOTICS SUPPLEMENTS NECESSARY?
Probiotics supplements are not necessary for normal, healthy individuals. In healthy individuals, daily consumption of Probiotics rich foods, particularly fermented dairy products like yoghurt and Curd adequately supplies the amount of Probiotics required to maintain a healthy digestive system and overall wellbeing. Whereas in people who are suffering from different kind of diseases like irritable bowel syndrome, diarrhea etc, they might need additional supplements. It is required to take prescription from doctors before going for any additional supplements. Diet high in starches and fibre provide Prebiotics, which keep a healthy population of Probiotics in our intestines. Due to the multitude of strains, the FDA has not approved any specific health claims for Probiotics. The varying strains also make it impossible to establish an RDA for a Probiotic. Probiotic effects should be considered dose specific. Dose listed on the label are based on studies that show a beneficial health effect in humans.