AntioxidantsAntioxidants are substances, which retard or prevent deterioration, damage or destruction caused by oxidation. Fortunately, the body has an army of antioxidants for damage limitation. Antioxidant form an integral part of the nutraceutical market. During the last few years’ research has confirmed that many have the common disease and ailments of 21st century (CVS, diabetes, cataracts, high blood pressure, infertilities, respiratory infection, and rheumatoid arthritis) are associated with tissue deficiency and/or low dietary levels of compounds called antioxidants. The oxygen is consumed in the body during metabolism by process called oxidation. During oxidation free radicals are generated. These free radicals at a molecular level burn everything they touch24. Antioxidants are power full electron donors and react with free radical damage the biomolecules. The formed antioxidant radical is stable and unreactive1. Antioxidants are quite large in
number and diverse in nature which oppose the process of oxidation largely by neutralizing free radicals at relatively small concentrations have the potential to inhibit to inhibit the oxidants chain reactions 25. Dietary antioxidants and some accessory molecules, such as zinc and certain vitamins are important in maintaining free radical scavenging systems, biosynthetic capacity, membranes, enzymes and DNA26. Antioxidants are found in the vegetable oils. e.g. Soybean oil, canola oil, corn oil, oat oil, wheat germ oil, palm oil, evening prime rose oil 27.
A free radical has defined as any species capable of independent existence that contain one more unpaired electron. Unpaired electron makes the molecule unstable and highly reactive. They are mainly derived from oxygen and nitrogen28. Free radicals are short lived. Most of the free radicals are formed in the body from oxygen are super oxide, hydroxyl radical, nitric oxide, singlet oxygen, peroxyl radical, hydrogen peroxide and alkoxyl. The sources of free radicals are both endogenous and exogenous.
The free radicals disrupt the equilibrium of biological systems by damaging their major constituents’ molecules (lipids, proteins, carbohydrates and DNA) that eventually lead to cell death.
Action of antioxidants
Antioxidants are used to prevent the damage at the cellular level by using the following mechanisms: § They may reduce the energy of the free radical § Preventive (suppress radical formation) § Repair (repair damage and reconstitute membranes)
Probiotics are live microbial food ingredients, which are beneficial to health. The prerequisite for probiotic action include survival in and adhesion to specific areas of the gastrointestinal tract and competitive exclusion of pathogens or harmful antigens. Probiotics are situated as health or functional foods whereby they are ingested for their purported positive advantages in the digested tract and/or systemic area like the liver, brain, vagina or blood stream29. Colon is the most densely populated region of the gastrointestinal tract and harbors an estimated 500 different bacterial species.
Probiotic bacterial speciesThe various types of bacteria that are having the probiotics characteristics are- · Lactobacilli· Lactobacillus rhamnosus· Lactobacillus reuteri· Lactobacillus case· Bifidobacterium· Bifidobacterium lactis· Bifidobacterium longum· Bifidobacterium breve· Bifidobacterium infantis· Streptococcus· Lactococcus· Lactococcus platinum· Lactococcus reuteri· Lactococcus agilis· Enterococcus· Saccharomyces· Bacillus· Pediococcus
Characteristics of probiotic bacteriaBacteria should have the following features: 1. GRAS (generally recognized as safe) 2. In vitro resistance to hydrochloric acid and pancreatic juice 3. Produce antimicrobial substances 4. Compete with bad bacteria to adhere on the gut wall. 5. Compete for the nutrients and stimulate immunity and 6. Alter the intestinal micro flora balance, inhibit growth of harmful bacteria, promote good digestion, boost immune function and increase resistance to infection30.
Prebiotics are the substances, which reach to colon in intact form i.e. without getting depleted by the gastric pH and digestive acids. These prebiotics also selectively promote the growth of colonel probiotic bacteria; hence they act as fertilizers for these bacteria23. These are collective term for non-digestive but a fermentable dietary carbohydrate that may selectively stimulates growth of certain bacterial groups’ resident in the colon, such as Bifidobacteria, Lactobacilli considered to be beneficial for the human host31. e.g. –inulin, which is soluble dietary fibres and resistant to digestive enzyme and thus reaches to large intestine or colon essentially intact, where it is fermented by resistant bacteria, Lactobacilli. A range of oligosaccharides have been tested using various in vitro methods, animal models and human clinical trials are – 1. Fructo oligosaccharides 2. Inulins 3. Lactilol 4. Lactulose 5. Galacto-oligosaccharides 6. Soybean oligosaccharides 7. Lactosucrose 8. Isomalto-oligosaccharides 9. Gluco-oligosaccharides 10.Xylo-oligosaccharides
The food components or ingredients (prebiotics)
A prebiotic nature has been attributed to many food components that the food or food components29- 1. Resists host digestion, absorption and absorption processes. 2. Fermented by the microflora colonizing the gastrointestinal system. 3. Selectively stimulates the growth and/or the activity of one or a limited number of bacteria with the gastrointestinal system.
Polyunsaturated fatty acids
Essential fatty acids are needed for normal growth and development but cannot be synthesized by our body. Omega-3 fatty acids belong to this class. Long chain omega-3 fatty acids such as eicosapentaoic acid and docosagexanoic acids are built up in algae and plankton and the fish living on them. The natural vegetable oils and marine animal oils containing polyunsaturated fatty acid belong to Linoleic group (omega 6-type and omega 3-fatty acid) help to reduce cholesterol formation/deposition and prevent thromboxane formation. e.g. safflower oil, corn oil, soybean oil, mustard oil and marine fishes32. Evening primrose oil, flax oil, hemp seed, borage seede33. The following are diseases for which polyunsaturated fatty acids are preferred. · Heart disease and stroke · Rheumatoid arthritis · Inflammatory arthritis · Inflammatory bowel disease · Asthma · Cancer · Chronic lung failure · Kidney transplant
Dietary FibresDietary fibres are used in health food products for normalization of intestinal transit time. They have dual effect on intestinal transit. First effect is on the bulk faeces, which are often increased, in substantial proportion (127% after ingestion of 20 g of wheat bran, this action with insoluble fibres. The other effect if dietary fibres are upon the duration of transit, which gets normalized around in 48 hrs. Long transit time gets shortened and short transit get longer. Dietary fibres are categorized into two groups
Water soluble fibresSoluble fibres dissolve in water and form a gel that binds the stool and inhibit the non-propulsive colon contractions, helps in bulking of stool and their quick passage through digestive tract. Oats, dried beans, legumes, chicory.
Water insoluble fibresInsoluble fibres are present in brown rice, banana, vegetables and whole grains. Source of dietary fibres are –
- Fresh fruit: Apple, orange, apricot, plum, pineapple with fibres 18-30%
- Vegetables:Cabbage, carrot, lettuce, onion, tomato with fibres 9 to 12 %
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