Pro Bio Tics

DEPARTMENT OF DAIRY SCIENCE MADRAS VETERINARY COLLEGE CHENNAI-07 LPT-311 ASSIGNMENT ON:

PROBIOTICS

SUBMITTED TO: Dr.C.NARESH KUMAR Ph.D, PROFESSOR AND HEAD DEPARTMENT OF DAIRY SCIENCE

SUBMITTED BY: THANIGAIVEL.P BVM-06128-D BATCH

III-B.V.Sc & A.H

PROBIOTICS Probiotics are dietary supplements of live bacteria or yeasts thought to be healthy for the host organism. According to the currently adopted definition by FAO/WHO, probiotics are: ‘Live microorganisms which when administered in adequate amounts confer a health benefit on the host’. Lactic acid bacteria (LAB) are the most common type of microbes used. LAB have been used in the food industry for many years, because they are able to convert sugars (including lactose) and other carbohydrates into lactic acid. This not only provides the characteristic sour taste of fermented dairy foods such as yogurt, but also, by lowering the pH, may create fewer opportunities for spoilage organisms to grow, hence creating possible health benefits by preventing gastrointestinal infections. Strains of the genera Lactobacillus and Bifidobacterium, are the most widely used probiotic bacteria. Probiotic bacterial cultures are intended to assist the body's naturally occurring gut flora, an ecology of microbes, to re-establish themselves. They are sometimes recommended by doctors, and, more frequently, by nutritionists, after a course of antibiotics, or as part of the treatment for gut related candidiasis. In these cases, the bacteria that work well with our bodies (see symbiosis) may decrease in number, an event which allows harmful competitors to thrive, to the detriment of our health. Claims are made that probiotics strengthen the immune system to combat allergies, excessive alcohol intake, stress, exposure to toxic substances, and other diseases. Maintenance of a healthy gut flora is, however, dependent on many factors, especially the quality of food intake.

HISTORY OF PROBIOTICS Probiotics, which means, "for life," have been used for centuries as natural components in health-promoting foods.The original observation of the positive role played by certain bacteria was first introduced by Russian scientist and Nobel laureate Eli Metchnikoff, who in the beginning of the 20th century suggested that it would be possible to modify the gut flora and to replace harmful microbes by useful microbes. Metchnikoff, at that time a professor at the Pasteur Institute in Paris, produced the notion that the ageing process results from the activity of putrefactive (proteolytic) microbes producing toxic substances in the large bowel. Proteolytic bacteria such as clostridia, which are part of the normal gut flora, produce toxic substances including phenols, indols and ammonia from the digestion of proteins. According to Metchnikoff these compounds were responsible for what he called "intestinal auto-intoxication", which caused the physical changes associated with old age. It was at that time known that milk fermented with lactic-acid bacteria inhibits the growth of proteolytic bacteria because of the low pH produced by the fermentation of lactose. Metchnikoff had also observed that certain rural populations in Europe, for example in Bulgaria and the Russian Steppes who lived largely on milk fermented by lactic-acid bacteria were exceptionally long lived. Based on these facts, Metchnikoff proposed that consumption of fermented milk would "seed" the intestine with harmless lactic-acid bacteria and decrease the intestinal pH and that this would suppress the growth of proteolytic bacteria. Metchnikoff himself introduced in his diet sour milk fermented with the bacteria he called "Bulgarian Bacillus" and found his health benefited. Friends in Paris soon followed his example and physicians began prescribing the sour milk diet for their patients. ADVERSE EFFECTS There is no published evidence that probiotic supplements are able to completely replace the body’s natural flora when these have been killed off; indeed bacterial levels in faeces disappear within days when supplementation ceases. While the oral use of probiotics is considered safe and even recommended by World Health Organization under specific guidelines, in some specific situations

(such as critically ill patients) they could be potentially harmful. In one therapeutic clinical trial, a probiotic cocktail increased the death rate of patients with acute pancreatitis Probiotics have been shown to be beneficial for other types of patients POTENTIAL BENEFITS Experiments into the benefits of probiotic therapies suggest a range of potentially beneficial medicinal uses for probiotics. For many of the potential benefits, research is limited and only preliminary results are available. It should be noted that the effects described are not general effects of probiotics. Recent research on the molecular biology and genomics of Lactobacillus has focused on the interaction with the immune system, anti-cancer potential, and potential as a biotherapeutic agent in cases of antibiotic-associated diarrhoea, travellers' diarrhoea, pediatric diarrhoea, inflammatory bowel disease and irritable bowel syndrome.[4] All effects can only be attributed to the strain(s) tested, not to the species, nor to the whole group of LAB (or other probiotics). MANAGING LACTOSE INTOLERANCE As lactic acid bacteria actively convert lactose into lactic acid, ingestion of certain active strains may help lactose intolerant individuals tolerate more lactose than what they would have otherwise. In practice probiotics are not specifically targeted for this purpose, as most are relatively low in lactase activity as compared to the normal yogurt bacteria. PREVENTION OF COLON CANCER In laboratory investigations, some strains of LAB have demonstrated anti-mutagenic effects thought to be due to their ability to bind with heterocyclic amines, which are carcinogenic substances formed in cooked meat.Animal studies have demonstrated that some LAB can protect against colon cancer in rodents, though human data is limited and conflicting. Most human trials have found that the strains tested may exert anti-carcinogenic effects by decreasing the activity of an enzyme called β-glucuronidase(which can generate carcinogens in the digestive system). Lower rates of colon cancer

among higher consumers of fermented dairy products have been observed in some population studies. LOWERING CHOLESTEROL Animal studies have demonstrated the efficacy of a range of LAB to be able to lower serum cholesterol levels, presumably by breaking down bile in the gut, thus inhibiting its reabsorption (which enters the blood as cholesterol). Some, but not all human trials have shown that dairy foods fermented with specific LAB can produce modest reductions in total and LDL cholesterol levels in those with normal levels to begin with, however trials in hyperlipidemic subjects are needed. LOWERING BLOOD PRESSURE Several small clinical trials have shown that consumption of milk fermented with various strains of LAB can result in modest reductions in blood pressure. It is thought that this is due to the ACE inhibitor-like peptides produced during fermentation. IMPROVING IMMUNE FUNCTION AND PREVENTING INFECTIONS LAB are thought to have several presumably beneficial effects on immune function. They may protect against pathogens by means of competitive inhibition (i.e., by competing for growth) and there is evidence to suggest that they may improve immune function by increasing the number of IgA-producing plasma cells, increasing or improving phagocytosis as well as increasing the proportion of T lymphocytes and Natural Killer cells.Clinical trials have demonstrated that probiotics may decrease the incidence of respiratory tract infections and dental caries in children. LAB foods and supplements have been shown to be effective in the treatment and prevention of acute diarrhea, and in decreasing the severity and duration of rotavirus infections in children and travelers' diarrhea in adults. Recently, clear immune enhancing effect of probiotics is demonstrated in the gut of healthy subjects. In a randomized, double blind, placebo controlled, crossover study, healthy volunteers ingested either live probiotic cells (Lactobacillus plantarum), inactivated cells of the same probiotic, or a placebo. Gene

expression analysis of biopsies from the duodenum has shown clearly the effect of the live probiotic on cellular processes. These processes activate the immune system enabling it to play its protective role (the immune response).

HELICOBACTER PYLORI LAB are also thought to aid in the treatment of Helicobacter pylori infections (which cause peptic ulcers) in adults when used in combination with standard medical treatments. ANTIBIOTIC-ASSOCIATED DIARRHEA A meta-analysis suggested probiotics may reduce antibioticassociated diarrhea. A subsequent randomized controlled trial also found benefit in elderly patients. In a randomized clinical trial, published in 2007, a University of Montreal team of pharmacologists demonstrated that lactobacillifermented solution can be effective in AAD prevention in hospitalized patients”. REDUCING INFLAMMATION LAB foods and supplements have been found to modulate inflammatory and hypersensitivity responses, an observation thought to be at least in part due to the regulation of cytokine function.Clinical studies suggest that they can prevent reoccurrences of inflammatory bowel disease in adults, as well as improve milk allergies.They are not effective for treating eczema, a persistent skin inflammation. Improving mineral absorption It is hypothesized that probiotic lactobacilli may help correct malabsorption of trace minerals, found particularly in those with diets high in phytate content from whole grains, nuts, and legumes. Prevents harmful bacterial growth under stress

In a study done to see the effects of stress on intestinal flora, rats that were fed probiotics had little occurrence of harmful bacteria latched onto their intestines compared to rats that were fed sterile water.

Irritable bowel syndrome and colitis B. infantis 35624, sold as Align, was found to improve some symptoms of irritable bowel syndrome in women in a recent study. Another probiotic bacterium, Lactobacillus plantarum 299v, was also found to be effective in reducing IBS symptoms.[Additionally, a probiotic formulation, VSL#3, was found to be safe in treating ulcerative colitis, though efficacy in the study was uncertain.Bifidobacterium animalis DN-173 010 may help. Synbiotics As probiotics are mainly active in the small intestine and prebiotics are only effective in the large intestine,the combination of the two may give a synergistic effect. Appropriate combinations of pre- and probiotics are synbiotics. Strains The most common form for probiotics are dairy products and probiotic fortified foods. However, tablets, capsules, powders and sachets containing the bacteria in freeze dried form are also available. Proven probiotic strains. Strain Brandname Lactobacillus Cultura casei F19

Producer Arla Foods

Proven effect in humans Improves digestive health, immune stimulation, reduces antibiotic-associated diarrhoea, induces satiety, metabolizes body fat, reduces weight gain

Lactococcus lactis L1A

Norrmejerier

GoodBelly / NextFoods ProViva/ Probi Ferring TuZen Lactobacillus BioGaia reuteri ATTC Biologics 55730 (Lactobacillus reuteri SD2112)

Immune stimulation, improves digestive health, reduces antibioticassociated diarrhoea

Lactobacillus plantarum 299V

Norrmejerier Verum Lactobacillus rhamnosus LB21 Saccharomyces cerevisiae (boulardii) lyo

DiarSafe and others

Wren Laboratories and others

Diarrhea prevention and mitigation in children, eradication of H. pylori infection,amelioration of gingivitis, general illness prevention i and adults Immune stimulation, improves digestive health, reduces antibioticassociated diarrhea against antibiotic-associated diarrhoea and [[Clostridium difficile]] infections; to treat acute diarrhoea in adults & children.

Some commonly used bacteria in products, but without probiotic effect (yoghurt bacteria): • •

Lactobacillus bulgaricus Streptococcus thermophilus

Some other bacteria mentioned in probiotic products: • •

Bacillus coagulans Lactobacillus bifidus - became new genus Bifidobacterium

Benefits of Probiotics The following is a list of some of the known benefits of probiotics:

Hydrocarbons are broken down by probiotic bacteria which means the food is being split into its most basic elements. This allows almost total absorption through the digestive system. In this way probiotics dramatically increase overall nutrition and enhance rapid cellular growth and development. The intestinal tract is cleaned by probiotics. They go under the layer of crud on the intestinal walls, attach themselves and dislodge the accumulated decay. This waste is then flushed out naturally. Probiotics also produce many important enzymes and increase the availability of vitamins and nutrients, especially Vitamin B, Vitamin K, lactase, fatty acids and calcium. Another one of the benefits of probiotics is that the bacteria strengthen the immune system. Because of this support to the immune system, they have been used in alleviating allergies, chronic fatigue syndrome and systemic candida. Constipation is quickly relieved by probiotics and the bowel movements become normalized, which means diarrhea is also reduced. These good bacteria produce specific proteins that act as antigens. The reservoirs of nonspecific antigens are then available for the immune system to use in battling all kinds of different disease conditions. Key points • •

•

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People use probiotic products as CAM to prevent and treat certain illnesses and support general wellness. There is limited evidence supporting some uses of probiotics. Much more scientific knowledge is needed about probiotics, including about their safety and appropriate use. Effects found from one species or strain of probiotics do not necessarily hold true for others, or even for different preparations of the same species or strain. Tell your health care providers about any CAM practices you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.

Uses for health purposes There are several reasons that people are interested in probiotics for health purposes. This bacterial "balancing act" can be thrown off in two major ways: 1. By antibiotics, when they kill friendly bacteria in the gut along with unfriendly bacteria. Some people use probiotics to try to offset side effects from antibiotics like gas, cramping, or diarrhea. Similarly, some use them to ease symptoms of lactose intolerance—a condition in which the gut lacks the enzyme needed to digest significant amounts of the major sugar in milk, and which also causesgastrointestinalsymptoms. 2. "Unfriendly" microorganisms such as bacteria, yeasts, fungi, and parasites can balance. Researchers are exploring whether halt these unfriendly agents in the first place their growth and activity in conditions like: o o o o

o o o o

disease-causing also upset the probiotics could and/or suppress

Infectious diarrhea Irritable bowel syndrome Inflammatory bowel disease (e.g., ulcerative colitis and Crohn's disease) Infection with Helicobacter pylori (H. pylori), a bacterium that causes most ulcers and many types of chronic stomach inflammation Tooth decay and periodontal disease Vaginal infections Stomach and respiratory infections that children acquire in daycare Skin infections

References 1. FAO/WHO (2001) Health and Nutritional Properties of Probiotics in Food including Powder Milk with Live Lactic Acid Bacteria. Report of a Joint FAO/WHO Expert Consultation on Evaluation of Health and Nutritional Properties of Probiotics in Food Including Powder Milk with Live Lactic Acid Bacteria.

2. Nichols,

Andrew W. (2007). "Probiotics and athletic performance: A systematic review". Current Sports Medicine Reports (Current Medicine Group LLC) 6 (4): 269–273. doi:10.1007/s11932-007-0044-5. http://www.springerlink.com/content/x363q11g7878m4tj/. Retrieved on 6 November.

3. Tannock G (editor). (2005). Probiotics and Prebiotics: Scientific

Aspects (1st ed. ed.). Caister Academic Press. ISBN 978-1904455-01-8 . http://www.horizonpress.com/pro3.