Such as Spirulina and Arthrospira. In addition, there are polysaccharides (such as Coriolus versicolor polysaccharide and carrot nitrogen-containing polysaccharide) and protein hydrolysates (such as casein hydrolysate and α -lactalbumin). Vegetables, Chinese herbal medicines and wild plants in natural plants can also be used as prebiotics.
Extended data:
As a dietary supplement, prebiotics have beneficial effects on the host by selectively stimulating the growth and activity of bacteria in one or several colonies, thus improving the health of the host.
Successful prebiotics should be fermented by intestinal flora and not digested when passing through the upper digestive tract. Most importantly, it only stimulates the growth of beneficial bacteria, not harmful bacteria with potential pathogenicity or corruption activity.
At present, there are 10 kinds of functional oligosaccharides, including fructooligosaccharides, soybean oligosaccharides, galactooligosaccharides, isomaltooligosaccharides, xylooligosaccharides, mannooligosaccharides, chitosan oligosaccharides and lactitol. ?
Soybean oligosaccharides
Soybean oligosaccharide refers to the general name of oligosaccharides contained in soybean, which is mainly composed of stachyose (3.8%), raffinose (1. 1%) and sucrose (5%), and also contains glucose, fructose, galactose-inositol methyl ether, D- inositol methyl ether and so on. ?
The sweetness of soybean oligosaccharides is 70% of sucrose, and the energy is only 1/2 of sucrose. It is not easy to be digested and absorbed by animals, and has a proliferation effect on intestinal beneficial bacteria. ?
iso malto oligosaccharide
Isomalt α -glucose oligosaccharide (α-GOS), also known as α -oligosaccharide or branched oligosaccharide, contains at least one isomaltose bound by α- 1, 6- glycoside bond, and other glucose molecules can be bound by α- 1, 2- glycoside bond and α- 1. It mainly contains isomaltose, panose, isomaltose, isomaltose and so on.
Isomaltooligosaccharide products include solid powder and liquid syrup. Isomaltooligosaccharide can improve the structure of intestinal flora and promote the proliferation of beneficial bacteria. Long-term feeding experiment proved that isomaltooligosaccharide is a kind of sweetener with high safety. ?
Xylooligosaccharides
Xylo-oligosaccharide is a linear sugar formed by combining 2- 10 D- xylose with β- 1 4- glycoside bond, which mainly contains xylobiose, xylotriose, xylotetraose and a small amount of xylose, xylopentose, xylohexose and xyloheptaose. There are two kinds of products: powdery solid and slurry liquid. At present, the main application is the oligomer formed by the combination of 2-7 D- xylose through β- 1, 4- glycoside bond. ? [4]?
The sweetness of xylooligosaccharide is lower than sucrose and glucose, similar to maltose, about 40% of sucrose. Its energy value is almost zero, which neither affects the blood sugar concentration nor increases the insulin level in blood sugar. And does not form fat deposits, so it can play a role in low-energy foods;
Xylo-oligosaccharides have good stability to pH and heat, and are basically not decomposed even when heated under acidic conditions (pH 2.5-7). Xylo-oligosaccharides are extremely difficult to be digested and absorbed by animals, with high intestinal residue rate and excellent proliferation of Bifidobacterium. It is an oligosaccharide with the strongest function of multiplying Bifidobacterium, and its efficacy is 15-20 times that of other oligosaccharides. Its selective utilization rate is also higher than other functional oligosaccharides. ?
At present, the physiological functions of xylooligosaccharides confirmed by research mainly include the following aspects: ① providing lower energy; (2) activating intestinal Bifidobacterium, promoting its proliferation, inhibiting pathogenic bacteria and preventing diarrhea; ③ Enhance immunity and fight cancer; ④ Prevent animals from biting their ears and pecking their anus; (5) can promote the body to produce various nutrients,
Comprise vitamin B 1, vitamin B2, vitamin B6, vitamin B 12, nicotinic acid and folic acid; ⑥ Prevent and protect dental caries and inhibit the growth of oral bacteria. ?
Microalgae (invisible to the naked eye)
Microalgae are widely distributed in soil, swamps, fresh water and hot springs, and can also grow in some extreme environments that are not suitable for other organisms, such as lakes with high salinity. There are many kinds of microalgae. Edible microalgae such as Chlorella and Spirulina are rich in protein, carotene, vitamins, seaweed polysaccharides, polyunsaturated fatty acids and chlorophyll.
The protein content of microalgae is very high, and the algal polysaccharide complex contained in microalgae can be used as an immune adjuvant to enhance antigenicity and immune function, play an anti-tumor role and increase its value as a prebiotic. The content of carotenoids in microalgae is very high, which has the functions of coloring and nutrition. Microalgae can also be used as raw materials to produce food additives such as vitamins and food pigments, or to extract food pigments such as phycocyanin, chlorophyll, astaxanthin, carotene-like I and carotenoids from microalgae.
In recent years, food additives with health care functions, such as EPA, DHA and other polyunsaturated fatty acids and polysaccharides, have been developed from microalgae. Some microalgae prebiotics such as spirulina can be selectively absorbed after entering the body, increasing the number of bifidobacteria and enhancing the immune ability of the body. Because of this, it was recommended by FAO as "the most ideal health food for human beings in 2 1 century". ?
In the past 30 years, the industrialized spirulina biotechnology industry at home and abroad has developed rapidly, with many products and high output value, and has sprung up in the field of microalgae industry, attracting worldwide attention. The large-scale industrial production of spirulina has great economic potential. Developing spirulina resources is not only conducive to developing new nutritional sources, alleviating the energy and food crisis, but also conducive to promoting the transformation from traditional agriculture to modern agriculture. ?
Natural plant
China is rich in Chinese herbal medicine and natural plant resources. In recent years, there has been an upsurge of using natural herbs to prevent and treat various diseases all over the world. Chinese herbal medicine is a substance with both nutritional and medicinal functions, which can adjust the balance of intestinal flora and improve the morphological structure of intestinal tract. Extracts of effective components from Chinese herbal medicines and natural plants can be used as important prebiotic products. ?
efficacy
Physiological efficacy
Prebiotics can promote the growth and reproduction of intestinal beneficial bacteria in the body, form microecological competitive advantage, optimize intestinal microecological balance, and then improve immunity to maintain the health of the body. Meanwhile, it can improve intestinal microecology. For example, oligosaccharides can promote the proliferation of intestinal beneficial bacteria Bifidobacterium and Lactobacillus, while some antibacterial substances produced by short-chain fatty acids and beneficial bacteria metabolism can directly inhibit the growth and reproduction of exogenous pathogenic bacteria and intestinal spoilage bacteria such as Bacteroides, Clostridium and Escherichia coli.
Bifurcation of prebiotics;
Most prebiotics identified so far can promote the proliferation of Bifidobacterium, and its mechanism is that prebiotics selectively stimulate the proliferation of Bifidobacterium in many intestinal flora. This may be because the growth efficiency of Bifidobacterium is relatively higher than other microorganisms, and it can tolerate short-chain fatty acids (SCFA) and acidification microenvironment caused by fermentation.
The analysis of the genome of Bifidobacterium longum reveals a large number of protein sequences that specifically catabolize various carbohydrates, which will undoubtedly help to improve the competitiveness in the intestinal environment. ?
Prebiotics can induce the increase of Bifidobacterium flora in intestinal tract by 10- 100 times, (Rao, 1999). It is concluded that the Bifidobacterium effect of prebiotics is inversely proportional to the original size of Bifidobacterium flora, which is more important than the dosage of prebiotics. ?
Characteristics of prebiotic soluble dietary fiber: Oligosaccharide prebiotics have the basic characteristics of soluble dietary fiber. For example, it can reduce the pH value of feces; Reduce toxic metabolites; Increase fecal volume and moisture, accelerate intestinal peristalsis and relieve constipation; Has the functions of clearing intestine, relaxing bowels and expelling toxin.
In addition, oligosaccharide prebiotics have good digestion resistance, are not easily decomposed by enzymes in saliva, pancreatic juice and intestinal juice, and can reach the large intestine and be metabolized by intestinal bacteria.
Health effects of prebiotics: Although the mechanism of prebiotics is theoretical to a great extent, reasonable assumptions that can be adopted include improving the activity and metabolic activity of microbial flora, which has the advantages of enhancing intestinal colonization resistance, promoting the absorption of mineral elements, improving immunity, nutrition and anti-tumor effects of short-chain fatty acids (SCFA), relaxing bowels and reducing the metabolism of harmful microorganisms. ?
Improve and prevent constipation. The intake of functional oligosaccharides leads to an increase in the number of bifidobacteria. The fermentation of oligosaccharides by Bifidobacterium in the intestine produces a large number of short-chain fatty acids such as acetic acid and lactic acid, which can promote intestinal peristalsis, increase the wetness of feces and maintain a certain osmotic pressure, so it can improve and prevent constipation. Studies have shown that taking 6- 12g oligosaccharide every day has obvious anti-constipation effect within one week. ?
Promote the absorption of mineral elements. After microbial fermentation, oligosaccharide prebiotics can reduce intestinal pH and improve mineral solubility, thus promoting the absorption of calcium, magnesium and other minerals in large intestine. It was found that FOS supplementation can increase the absorption of calcium and magnesium in rats, increase the calcium content in femur and prevent the occurrence of fecal addiction.
In particular, it can improve the stimulating effect of FOS on magnesium absorption. Goss intake can not only effectively promote the intestinal absorption of calcium, but also reduce the intestinal absorption of sodium and improve the absorption rate of potassium.
Immune regulation, anti-tumor. Probiotics can be used by beneficial bacteria such as Bifidobacterium and Lactobacillus to produce metabolites, which can further promote their digestion, growth and proliferation, thus stimulating the growth of intestinal immune organs, improving the activity of macrophages and improving the antibody level of the body.
The immunomodulation test of oligosaccharide prebiotics proved that oligosaccharide can obviously increase the number of antibody-forming cells and NK cell activity, and enhance immune function. A large number of animal experiments show that the proliferation of Bifidobacterium in intestine has anti-cancer effect, which is because the cells, cell walls and intracellular substances of Bifidobacterium improve immunity. ?
Regulate fat metabolism. Prebiotics can also affect fat metabolism. The experiment on diabetic rats showed that the serum cholesterol and triglyceride of the diseased rats decreased after replacing the sugar in the feed with xylooligosaccharide. Fructooligosaccharide was also tested, and the experimental results showed that it could reduce blood lipid. ?
Probiotics are fermented by beneficial bacteria in vivo to produce short-chain fatty acids, such as acetic acid, propionic acid, butyric acid and lactic acid. These organic acids can reduce the pH value and ammonia concentration in the intestine, effectively inhibit the production of intestinal spoilage products, promote intestinal peristalsis to promote defecation and improve lipid metabolism. ?
It was also confirmed that oligosaccharide probiotics can reduce the PH value of intestinal tract after microbial fermentation, resulting in the dissolution of calcium, phosphorus and magnesium complexes formed in small intestine, which is beneficial to the absorption of calcium, magnesium and other minerals in intestinal tract, and will be of great significance for promoting the growth and development of children and preventing osteoporosis. ?
Prebiotics can also enhance human immunity. Beneficial bacteria such as Bifidobacterium and Lactobacillus can use prebiotic nutrition to promote their own growth and proliferation, thus stimulating macrophages to produce activity. Activated macrophages will secrete antibiotics, and also promote lymphocyte division and proliferation, so that intestinal immune organs can grow, thus improving the body's immunity. ?
Eating prebiotics regularly in daily diet will be beneficial to human nutrition and health. Fructooligosaccharides can be added to breakfast cereals such as oatmeal and crispy rice chips, and drinks, sweets, cakes and health foods rich in oligosaccharides can also be eaten. For infants who can't breastfeed but have to rely on artificial feeding, in order to help them improve the intestinal barrier function, we can choose infant dairy products with fructooligosaccharides and galactooligosaccharides.
References:
Prebiotics