Prebiotics are “a non-digestive food element that beneficially impacts the host by selectively encouraging the growth and activity of one or a restricted number of bacteria in the colon, and thereby improves human health,” according to Gibson and Roberfroid [x] . The definition of prebiotics as provided by these authors is now as follows: “selectively fermented component that allows specified modifications; both in the composition and activity in the gut microbiota that confers benefits upon host well-being and health” [x]. The most recent definition equates “prebiotic” to”bifidogenic,” and it includes the prebiotic index (i.e., it gives the absolute increase of the fecal bifidobacteria concentration per gram of daily consumed prebiotics).
Candidate prebiotics must meet the following requirements, which must be demonstrated through in vitro and in vivo tests: (1) non-digestibility (resistance to low pH gastric acid, enzymatic digestion, and intestinal absorption); (2) fermentation by the intestinal microbiota; and (3) specific stimulation of growth and increased activity of intestinal bacteria [x].
Prebiotics are sometimes described as “a non-viable dietary component that delivers a health benefit on the host, associated with regulation of the microbiota” [x]. This definition developed from research showing that certain dietary fibers can alter the gut microbiota in various ways, most notably by increasing the cell counts of bifidobacteria and lactobacilli or reducing potentially dangerous bacteria.
Prebiotics are generally understood to be good for our health and well-being because they provide food for commensal and regulatory bacterial species. According to scientific consensus, prebiotics is valuable dietary supplements for regulating the growth and activity of particular bacterial species in the colon that are thought to benefit health.
High and Low Molecular Weight Prebiotics
The molecular weight of prebiotics affects their physical and functional properties, such as solubility, viscosity, and fermentability by gut microbiota. Additionally, the molecular weight influences their ability to resist degradation in the upper gastrointestinal tract, which affects the extent of delivery to the lower gastrointestinal tract, where the gut microbiota reside. Therefore, the molecular weight of a prebiotic can impact their effectiveness, and thus, is an important consideration when discussing prebiotics.
High molecular weight (HMW) prebiotics and low molecular weight (LMW) prebiotics differ in terms of:
- Site of fermentation: HMW prebiotics are typically fermented in the colon, whereas LMW prebiotics are fermented in the small intestine.
- Health benefits: The site of fermentation can impact the health benefits provided by the prebiotic. HMW prebiotics may promote the growth of a more diverse range of gut bacteria, including butyrate-producing bacteria, which have been linked to improved gut health and reduced inflammation.
- Fermentation speed: LMW prebiotics are typically fermented faster than HMW prebiotics, which can lead to increased gas production and gastrointestinal discomfort.
- Effect on blood sugar: LMW prebiotics can rapidly raise blood sugar levels, which may not be beneficial for individuals with blood sugar management concerns. HMW prebiotics may have a more gradual effect on blood sugar levels and are generally considered to be more suitable for individuals with blood sugar management concerns.
LMW prebiotics are also fermented more proximally in the gastrointestinal tract than HMW prebiotics, which are fermented more distally. Overall, both HMW and LMW prebiotics have health benefits, but the specific benefits can depend on the individual and the type of prebiotic consumed.
The range of molecular weight for low molecular weight prebiotics is generally below 1,000 Da, while the range for high molecular weight prebiotics is above 1,000 Da. However, there is no strict cutoff value, and molecular weight can vary depending on the type of prebiotic and the method used to determine its weight. Table 1.1 offers a comprehensive list of prebiotics, prebiotic subtypes, sources, and associated molecular weights.
Prebiotics, Subtype, Sources, and Molecular Weight
|Inulin||Native Inulin, Fructooligosaccharides, Modfied Inulin, Inulin-type Fructans, High-Purity Inulin||chicory root, Jerusalem artichokes, garlic, and onions, pharmaceutical grade prebiotic supplements.||2,000 to 60,000 Da|
|Fructooligosaccharides (FOS)||Native FOS, Synthetic FOS, Isolated FOS, FOS-Enriched Inulin, Combination FOS||Chicory root, Jerusalem artichokes, Agave, Garlic,Onions, Leeks, Asparagus, Bananas||200-2000 Da|
|Galactooligosaccharides (GOS)||Native GOS, Synthetic GOS, Isolated GOS, GOS-Enriched Lactose, Combination GOS.||Human Milk, Camel Milk, beans lentils and chickpeas, barley, oats, rye, soybeans, kefir, yogurt.||5000-10000 Da|
|Xylooligosaccharides (XOS)||XOS) come in different chain lengths, from XOS 2 to XOS 10||birch tree xylan, corn cobs, sugar beet fibers, and wheat bran||300-6000 Da|
|Arabinooligosaccharides (AOS)||Arabinogalactans||Gum Arabic/ Gum Acacia; Mastic Gum/ Mastiha; Gum Tragacanth; Larch||700-3000 Da|
|Resistant Starch||Type 1 RS Type 2 RS Type 3 RS Type 4 RS||whole grains and seeds, raw potatoes, green bananas, and plantains, cooked and cooled pasta and rice, and resistant maltodextrins.||7,000-7,000,000 Da|
|Pectin||High Methoxy Pectin, Low Methoxy Pectin, Modified Pectin, Pectin from Citrus, Pectin from Apple||Citrus fruits, apples, stone fruits, some vegetables||50,000 to 2,000,000|
|Beta-glucans||(1,3)-beta-glucan; (1,4)-beta-glucan; (1,6)-beta-glucan. (1,3)-(1,6)-beta-glucan, (1,3)-(1,4)-beta-glucan, (1,4)-(1,6)-beta-glucan||Oats, Barley Yeast, Mushrooms, Algae, Seaweed||7,000-7,000,000 Da|
|Mannan-oligosaccharides (MOS)||linear mannan, glucomannan, galactomannan, and galactoglucomannan.||Yeast cells (Saccharomyces cerevisiae), Konjac root, guar beans, psyllium husk, and synthetic production from yeast mannan or other polysaccharides||1000-10,000 Da|
|Trans-galactooligosaccharides (TOS)||Lactobacillus-fermented TOS, Enzymatically-synthesized TOS||Trans-galactooligosaccharides (TOS) are not naturally found in significant amounts in the diet.||300-6000 Da|
|Oligofructose||Inulin-type fructans, Short-chain fructooligosaccharides (scFOS), Long-chain fructooligosaccharides (lcFOS), Synthetic FOS||Chicory root, agave, dahlia, Jerusalem artichoke, onions||500-6000 Da|
|Lactulose||Not classified into different types, but it may have different specifications regarding purity, degree of hydration, and particle size.||Lactulose is a synthetic sugar and is not found in natural sources.||342.3 Da|
|Cellulose||hydrolyzed cellulose, hemicellulose||Fruits, vegetables, grains, and legumes. It can also be derived from wood pulp and other plant fibers.||10,000 to 400,000 g/mol.|
|Hemicellulose||Xylan, Glucuronoxylan, Mannan, Galactan, Arabinogalactan, Xyloglucan||whole grains, legumes, seeds, and nuts.||3,000 – 10,000 Da|
|Pectic oligosaccharides||Galacturonans, Rhamnogalacturonans, Apiogalacturonans, Xylogalacturonans, Arabinogalactan, Homogalacturonans||citrus fruits, apples, pears, carrots||300-3000 Da|
|Soy oligosaccharides||Raffinose, Stachyose, Verbascosem Isofucose, 6-kestose||Soy milk, soy protein powder, tofu||300-800 Da|
|Glucomannan||There is typically one type of glucomannan, but it may vary in terms of purity, particle size, and processing method.||Konjac Root, Konjak flour, Shiritaki noodles||50,000- 2,000,000 Da|
|Chitooligosaccharides (COS)||Glucosamine oligosaccharides, N-acetylglucosamine oligosaccharides, Galactosamine oligosaccharides, N-acetylgalactosamine oligosaccharides||crab shells, shrimp shells, and squid pens, insects, kimchi, natto.||300-6000 Da|
Comprehensive List of Prebiotics
Inulin is a type of soluble fiber that is found in many different plants, including chicory root, Jerusalem artichokes, garlic, and onions. There are several different types of inulin, including:
- Native Inulin: This is the unmodified form of inulin that is found naturally in plants. It has a unique chemical structure and functional properties, and is used as a prebiotic fiber to promote the growth of beneficial gut bacteria.
- Fructo-Oligosaccharides (FOS): This type of inulin is comprised of short chains of fructose molecules and is commonly used as a prebiotic fiber to support digestive health.
- Modified Inulin: This type of inulin is chemically or physically modified to alter its functional properties, and is used in a variety of food and industrial applications.
- Inulin-type Fructans: This type of inulin is a type of fructan that is found in a variety of plants, and is used as a prebiotic fiber and as a fat replacer in food products.
- High-Purity Inulin: This type of inulin is highly purified, and is used in a variety of food, pharmaceutical, and industrial applications.
Fructooligosaccharides (FOS) are a type of soluble fiber that is made up of short chains of fructose molecules. There are several different types of FOS, including:
- Native FOS: This is the unmodified form of FOS that is found naturally in some plants, including chicory root and Jerusalem artichokes.
- Synthetic FOS: This type of FOS is made by chemically synthesizing the fructose molecules and linking them together to form the desired chain length.
- Isolated FOS: This type of FOS is obtained from natural sources and then purified to a high degree to remove impurities.
- FOS-Enriched Inulin: This type of FOS is made by treating native inulin with an enzyme to break down the chains of fructose molecules into shorter lengths, resulting in a mixture of inulin and FOS.
- Combination FOS: This type of FOS combines different types of FOS, inulin, and other soluble fibers to create a final product with unique properties and functionalities.
FOS can be synthesized chemically or produced through the enzymatic modification of inulin or other soluble fibers. These modified forms of FOS are commonly used as food ingredients, supplements, and functional food additives due to their ability to support digestive health and promote the growth of beneficial gut bacteria.
Galactooligosaccharides (GOS) are a type of soluble fiber made up of short chains of galactose molecules. There are several different types of GOS, including:
- Native GOS: This is the unmodified form of GOS that is found naturally in some plants, including lactose and human milk.
- Synthetic GOS: This type of GOS is made by chemically synthesizing the galactose molecules and linking them together to form the desired chain length.
- Isolated GOS: This type of GOS is obtained from natural sources and then purified to a high degree to remove impurities.
- GOS-Enriched Lactose: This type of GOS is made by treating lactose with an enzyme to break down the chains of galactose molecules into shorter lengths, resulting in a mixture of lactose and GOS.
- Combination GOS: This type of GOS is made by combining different types of GOS, lactose, and other soluble fibers to create a final product with unique properties and functionalities.
Galactooligosaccharides (GOS) are found in some plants and animals, including:
- Human milk: GOS is one of the primary components of human milk, where it supports the growth of beneficial gut bacteria and helps protect against infections.
- Legumes: Some legume plants, such as beans, lentils, and chickpeas, contain small amounts of GOS.
- Certain Grasses: Grasses such as barley, oats, and rye contain small amounts of GOS.
- Soybeans: Some soybean varieties contain significant amounts of GOS.
- Some Fermented Foods: Fermented foods, such as kefir and yogurt, contain small amounts of GOS due to the action of bacteria during the fermentation process.
GOS can also be synthesized chemically or produced through the enzymatic modification of other soluble fibers, such as lactose, to create specific types of GOS with desired properties and functionalities. These modified forms of GOS are commonly used as food ingredients, supplements, and functional food additives due to their ability to support digestive health and promote the growth of beneficial gut bacteria.
Xylooligosaccharides (XOS) are prebiotic dietary fibers composed of xylose monomers linked by β-1,4 glycosidic bonds. They are found in small amounts in various plant materials and are commercially produced by enzymatic hydrolysis of xylan, a polysaccharide component of hemicellulose. XOS are recognized for their bifidogenic properties, meaning they selectively promote the growth of beneficial bacteria such as bifidobacteria in the gut.
Xylooligosaccharides (XOS) come in different chain lengths, from XOS 2 to XOS 10, with different molecular weights. The molecular weight of XOS can vary, as it is a class of oligosaccharides with varying degrees of polymerization. The molecular weight range can be from a few hundred daltons to several thousand daltons. These different types of XOS offer different benefits, including different solubility, sweetness, and fermentability properties.
Xylooligosaccharides can be found naturally in various sources, such as birch tree xylan, corn cobs, sugar beet fibers, and wheat bran. They can also be produced through the enzymatic hydrolysis of xylan from these sources or from cornstarch.
Arabinooligosaccharides are short chains of sugars made up of arabinose units. AOS can be found in a variety of natural sources, including:
- Plants: AOS can be extracted from certain plants such as soybeans, wheat, and barley.
- Dairy products: Some dairy products, such as breast milk, contain AOS.
- Fermented foods: Certain fermented foods, such as miso and tempeh, contain AOS as a result of the fermentation process.
- Supplements: AOS can also be obtained from dietary supplements in the form of a prebiotic ingredient.
Arabinogalactans are a type of polysaccharide, a complex carbohydrate molecule, made up of units of both arabinose and galactose sugars. The molecular weight of Arabinooligosaccharides (AOS) ranges from several hundred to a few thousand daltons. The exact molecular weight can vary depending on the length and structure of the individual oligosaccharides in the AOS mixture.
Arabinogalactan is found in a variety of plants, including larch trees, and has been shown to have various potential health benefits. These include boosting the immune system, promoting healthy gut bacteria, and having prebiotic effects to support digestive health. Additionally, several arabinogalactans have been suggested to have potential therapeutic applications, such as in the treatment of certain types of cancer.
- Gum Arabic / Gum Acacia
- Mastic Gum / Mastiha
- Gum Tragacanth (Astralagus gummifer)
- Guar Gum
- Locust Bean Gum
- Gum Karaya /gum sterculia
Resistant Starch (RS)
Resistant starch (RS) is a type of starch that is resistant to digestion by human digestive enzymes, passing through the small intestine undigested and reaching the colon where gut bacteria ferment it. There are several different types of resistant starch, including:
- Type 1 RS: This type of RS is found in unprocessed whole grains and seeds and is also known as “physically inaccessible starch”. It is physically trapped within the plant cell walls and is not easily digested by human digestive enzymes.
- Type 2 RS: This type of RS is found in certain types of starchy foods, such as raw potatoes, green bananas, and plantains. It is a resistant starch that is inherently present in these foods and is not easily digested due to its high amylose content.
- Type 3 RS: This type of RS is formed through a process of cooking and cooling starchy foods, such as pasta or rice. When these foods are cooked and then cooled, the starch crystals re-arrange in a way that makes them resistant to digestion.
- Type 4 RS: This type of RS is produced through chemical modification and is also known as “resistant maltodextrin”. It is used as a food ingredient and is typically found in processed foods.
Each type of resistant starch has unique properties and potential health benefits, including improved gut health, increased satiety, and reduced insulin resistance.
The molecular weight of the 4 types of Resistant Starch (RS) varies depending on the type and its specific composition. However, they are typically in the range of several thousand to several million daltons.
Pectin is a type of polysaccharide that is found in many fruits and vegetables, and is commonly used as a gelling agent in food products. There are several different types of pectin, including:
- High Methoxy Pectin: This type of pectin is widely used in the food industry due to its high gel strength and stability. It is commonly used in jellies, jams, and other fruit-based products.
- Low Methoxy Pectin: This type of pectin has a lower gel strength compared to high methoxy pectin, and is typically used in applications where a softer gel is desired.
- Modified Pectin: This type of pectin is modified chemically or physically to alter its properties, and is used in a variety of food and industrial applications.
- Pectin from Citrus: This type of pectin is derived specifically from citrus fruits, such as oranges, and is used in a range of food and pharmaceutical products.
- Pectin from Apple: This type of pectin is derived specifically from apples, and is used as a thickener and gelling agent in food products.
The type of pectin used in a particular application depends on factors such as the desired properties of the final product, as well as the processing and storage conditions. Each type of pectin has unique properties, including gel strength, stability, and solubility, which can impact the final product characteristics.
Some of the familiar natural sources of pectin include:
- Apples: Apples are one of the richest sources of pectin, and are commonly used in the production of jellies, jams, and other fruit-based products.
- Citrus fruits: Citrus fruits, such as oranges and lemons, are another rich source of pectin and are commonly used in the production of marmalades and fruit preserves.
- Berries: Berries, such as strawberries, blackberries, and raspberries, are also rich in pectin and are commonly used in the production of jellies and jams.
- Stone fruits: Stone fruits, such as peaches, plums, and apricots, contain a moderate amount of pectin and are used in the production of fruit-based products, such as jams and pie fillings.
- Vegetables: Some vegetables, such as carrots and onions, contain small amounts of pectin and are used in the production of pickles and other preserved foods.
The pectin content of fruits and vegetables can vary depending on factors such as the type of fruit or vegetable, its ripeness, and the growing conditions. To obtain a high yield of pectin, fruits and vegetables are often harvested at a specific stage of maturity when the pectin content is at its highest.
The molecular weight of pectin varies depending on the type and degree of methylation, but it generally ranges from 50,000 to 2,000,000 daltons.
Beta-glucans are soluble fibers that belong to a class of polysaccharides. There are several different types of beta-glucans, which can be classified by linkages and type.
Beta Glucans by type include:
- Oat Beta-Glucan: This is the most well-known and widely studied form of beta-glucan. It is found in high levels in oats and has been shown to have cholesterol-lowering and blood sugar-lowering effects.
- Barley Beta-Glucan: This type of beta-glucan is found in barley and has been shown to have similar health benefits as oat beta-glucan.
- Yeast Beta-Glucan: This type of beta-glucan is found in yeast, including baker’s yeast, and is commonly used as a food ingredient, dietary supplement, and functional food additive.
- Mushroom Beta-Glucan: This type of beta-glucan is found in some types of mushrooms, including shiitake, maitake, and reishi, and has been shown to have immune-boosting and cancer-fighting properties.
- Algae Beta-Glucan: This type of beta-glucan is found in some types of seaweed and algae and has been shown to have immunomodulatory and anti-inflammatory effects.
Beta-glucans are polysaccharides composed of glucose units linked by beta-glycosidic bonds. The type of beta-glucan linkage refers to the specific type of beta-glycosidic bond that connects the glucose units. Beta-glucans by common linkages include:
- (1,3)-beta-glucan: A beta-glucan linkage in which beta-1,3-glycosidic bonds link the glucose units. This type of beta-glucan is commonly found in yeast, fungi, and some bacteria.
- (1,4)-beta-glucan: A beta-glucan linkage in which beta-1,4-glycosidic bonds link the glucose units. This type of beta-glucan is commonly found in cereals, such as oats, barley, and rye.
- (1,6)-beta-glucan: A beta-glucan linkage in which beta-1,6-glycosidic bonds link the glucose units. This type of beta-glucan is less common than other beta-glucan linkages, but is found in some bacteria and fungi.
- (1,3)-(1,6)-beta-glucan: A beta-glucan linkage in which a combination of beta-1,3-glycosidic and beta-1,6-glycosidic bonds links the glucose units. This type of beta-glucan is commonly found in mushrooms, such as shiitake, maitake, and reishi.
- (1,3)-(1,4)-beta-glucan: A beta-glucan linkage in which a combination of beta-1,3-glycosidic and beta-1,4-glycosidic bonds links the glucose units. This type of beta-glucan is commonly found in seaweed, such as kelp, wakame, and irish moss.
- (1,4)-(1,6)-beta-glucan: A beta-glucan linkage in which a combination of beta-1,4-glycosidic and beta-1,6-glycosidic bonds links the glucose units. This type of beta-glucan is less common, but can be found in some bacteria and fungi.
The molecular weight of Beta-glucan varies depending on the specific beta-glucan, but it can range from several thousand to several million daltons. Each type of beta-glucan has unique properties, including solubility, viscosity, and stability, which can impact the health benefits and functionalities of the final product. The type of beta-glucan used in a particular application depends on factors such as the desired properties of the final product, as well as the processing and storage conditions. The specific type of beta-glucan linkage can affect the solubility, viscosity, and functional properties of the beta-glucan, as well as its potential health benefits.
Beta-glucans are soluble fibers that can be found in a variety of sources including:
- Grains: Oats, barley, and rye are some of the most common sources of beta-glucans, especially oat beta-glucan.
- Yeast: Baker’s yeast is a good source of yeast beta-glucan.
- Mushrooms: Some mushrooms, such as shiitake, maitake, and reishi, are good sources of mushroom beta-glucan.
- Seaweed and algae: Some types of seaweed and algae, such as kelp, wakame, and irish moss, are good sources of algae beta-glucan.
- Bacteria: Some bacteria, such as bacillus subtilis and bacillus licheniformis, produce beta-glucans as a by-product of their metabolism.
- Legumes: Some legumes, such as lentils, chickpeas, and beans, contain small amounts of beta-glucans.
In addition to these sources, beta-glucans can also be derived from a variety of other plants, including cereals, such as wheat and corn, and fungi, such as cordyceps, lion’s mane, and reishi. The content and quality of beta-glucans in these sources can vary greatly depending on a variety of factors, such as the variety of the plant, the growing conditions, and the processing conditions.
Small chains of mannose known as prebiotic mannooligosaccharides (MOS) are recognized to offer consumers health advantages. Currently, mannans from yeast cell walls are degraded to create commercial MOS. MOS can also be created by physically, chemically, or enzymatically processing mannans found in nature.
These oligomers have recently become known for their potential application as functional food ingredients for humans and their involvement in modulating the beneficial gut flora of animals. According to substantial experimental data, dietary MOS have enormous potential as a functional food ingredient since they offer a variety of positive health impacts, such as anticancer, immunomodulatory, and hypolipidemic effects. [x]
Linear mannan, glucomannan, galactomannan, and galactoglucomannan are different types of mannan-based polysaccharides.
- Linear mannan is a linear chain of mannose units.
- Glucomannan is a type of mannan where glucose units are attached to the mannose units.
- Galactomannan is a type of mannan where galactose units are attached to the mannose units.
- Galactoglucomannan is a type of mannan where both galactose and glucose units are attached to the mannose units.
- These polysaccharides can be found in plant sources, including guar beans, konjac root, and psyllium husk.
Mannan-oligosaccharides (MOS) are a type of prebiotic fiber and can be found in several forms, including:
- Yeast-derived MOS (Saccharomyces cerevisiae)
- Plant-derived MOS (e.g. from konjac root) (Amorphophallus konjac)
- Synthetically-made MOS from yeast mannan or other polysaccharides.
Trans-galactooligosaccharides (TOS) are prebiotic fibers, which are types of carbohydrates that are indigestible by human digestive enzymes but can be fermented by gut bacteria. TOS are made up of galactose units linked together to form short chains. The molecular weight of trans-galactooligosaccharides can vary depending on the degree of polymerization, which refers to the number of monosaccharides or simple sugars in a chain. The molecular weight can range from a few hundred to several thousand daltons.
They have been shown to promote the growth of beneficial gut bacteria, such as bifidobacteria, which can improve gut health. TOS are commonly used as a food ingredient to improve the digestive health of foods, especially dairy-based products such as yogurt and cheese. Trans-galactooligosaccharides can be found in two forms and made through two methods including:
- Lactobacillus-fermented TOS: This method involves fermenting lactose with a probiotic strain of Lactobacillus bacteria to produce TOS.
- Enzymatically-synthesized TOS: This method involves using an enzyme, such as alpha-galactosidase, to synthesize TOS from lactose. The enzyme cleaves lactose into galactose and glucose, which are then linked together to form TOS.
Trans-galactooligosaccharides (TOS) are not naturally found in significant amounts in the diet. They are usually synthesized from lactose in the laboratory and added to food products as a prebiotic ingredient. Some dairy products, such as human breast milk, contain small amounts of TOS.
Oligofructose is a type of fructooligosaccharide (FOS), a prebiotic fiber made up of short chains of fructose units. The molecular weight of oligofructose ranges from around 500 to 6000 daltons, depending on the degree of polymerization. Oligofructose is a type of fructooligosaccharide with a short chain length, typically composed of 2 to 10 fructose units.
There are several types of oligofructose, including:
- Inulin-type fructans: The most common type of oligofructose, which are found in plants such as chicory, agave, and dahlia.
- Short-chain fructooligosaccharides (scFOS): An oligofructose with a shorter chain length compared to inulin-type fructans.
- Long-chain fructooligosaccharides (lcFOS): An oligofructose with a longer chain length compared to inulin-type fructans.
- Synthetic FOS: A type of oligofructose synthesized in the laboratory using enzymes or other chemical processes.
All types of oligofructose have prebiotic properties, meaning they can promote the growth of beneficial gut bacteria and improve gut health. However, the specific benefits and effects may vary based on the type of oligofructose and its chemical structure.
Oligofructose is a type of fructooligosaccharide (FOS) that is found in some plants and can also be synthesized in the laboratory. Some natural sources of oligofructose include:
- Chicory root: One of the richest sources of inulin-type fructans, which is a type of oligofructose.
- Agave: A type of succulent plant that contains both inulin-type fructans and short-chain fructooligosaccharides (scFOS).
- Dahlia: A type of flowering plant that contains inulin-type fructans.
- Jerusalem artichoke: A type of root vegetable that is rich in inulin-type fructans.
- Onions: A type of vegetable that contains small amounts of inulin-type fructans.
Oligofructose is also available as a dietary supplement in powder or capsules. Synthetic FOS can also be found in some food and drink products, including low-carb and sugar-free products.
Lactulose is a type of soluble fiber that is not digestible by human enzymes, so it reaches the large intestine, where it is fermented by gut bacteria, promoting their growth and improving gut health.
Lactulose is a synthetic disaccharide that is made by chemically linking galactose and fructose molecules. It is generally not classified into different types, but it may have different specifications regarding purity, degree of hydration, and particle size. Some brands of lactulose may have additional ingredients added to the syrup or solution form to enhance its taste or stability.
Lactulose is a synthetic sugar and is not found in natural sources. Lactulose is made through an enzymatic process that involves the isomerization of lactose, a naturally occurring sugar found in milk and dairy products. The process involves treating lactose with an enzyme, such as lactase, in the presence of an acid catalyst to produce lactulose. This sugar is then purified and used as a sweetener and a prebiotic ingredient in food and medicinal products.
Cellulose is a linear, unbranched polymer of β-glucose monomers linked by β(1→4) glycosidic bonds. The molecular weight of cellulose depends on the number of glucose units in the chain.
Cellulose is a type of dietary fiber that cannot be broken down by human digestive enzymes but serves as food for the gut microbiota. It acts as a bulk laxative and helps regulate bowel movements. Cellulose fiber may also provide prebiotic activity if its solubility can be enhanced by enzymatic and diluted-acid hydrolysis to produce hydrolyzed cellulose.
Hydrolyzed cellulose is the cellulose that has undergone hydrolysis, a chemical process that breaks down polysaccharides into monosaccharides or oligosaccharides. Some common types of hydrolyzed cellulose include:
- Cellulose Hydrolysate
- Cellulose Gum
- Hydroxypropyl Cellulose
- Carboxymethyl Cellulose
- Methyl Cellulose
- Ethyl Cellulose
- Sodium Carboxymethyl Cellulose
Hydrolyzed cellulose shows prebiotic activity by promoting the growth of Lactobacillus plantarum, and L. casei [x].
Hemicellulose is a type of complex carbohydrate (polysaccharide) found in plant cell walls alongside cellulose. It is composed of different sugar molecules and is less abundant and structurally less organized compared to cellulose. Hemicelluloses are essential dietary fiber components and play a role in plant tissue’s structure, stability, and water-holding capacity.
Hemicellulose is prebiotic that is found in the cell walls of plants, along with cellulose and lignin. It is considered indigestible by humans but can provide health benefits by serving as a substrate for gut bacteria, promoting the growth of beneficial bacteria.
Hemicelluloses are a diverse group of polysaccharides found in plant cell walls, including:
Hemicellulose is found in various plant-based foods such as whole grains, legumes, seeds, and nuts.
Pectic oligosaccharides are short chains of pectin molecules, a type of polysaccharide found in the cell walls of many fruits and vegetables. They have been shown to have potential prebiotic effects, as they are not fully digested by human enzymes and can be fermented by gut bacteria to produce short-chain fatty acids.
There are several types of pectic oligosaccharides, including:
Pectic oligosaccharides are naturally found in various fruits and vegetables, including citrus fruits, apples, pears, carrots, and others. They can also be produced from pectin, a polysaccharide found in the cell walls of these foods, through hydrolysis using enzymes or other methods. The molecular weight of pectic oligosaccharides can vary depending on the specific composition and structure of the oligosaccharide. However, pectic oligosaccharides typically have molecular weights ranging from a few hundred to a few thousand Daltons.
Soy oligosaccharides are prebiotic fibers that are derived from soybeans. They are made up of simple sugars, such as glucose and fructose, that are linked together in a chain. The molecular weight of soy oligosaccharides varies depending on their composition and structure and ranges from about 300 to 800 Daltons.
Human digestive enzymes do not easily digest them, and instead are fermented by gut bacteria. The fermentation of soy oligosaccharides leads to the production of short-chain fatty acids, which have several health benefits, including supporting gut health and maintaining a healthy gut microbiome.
Soy oligosaccharides are indigestible carbohydrates that can be found in soybeans. There are several types of soy oligosaccharides, including:
- Raffinose: a trisaccharide composed of glucose, fructose, and galactose
- Stachyose: a tetrasaccharide composed of glucose, fructose, galactose, and another glucose molecule
- Verbascose: a hexasaccharide composed of glucose, fructose, galactose, and three additional glucose molecules
- Soy oligosaccharides: a mixture of the above oligosaccharides, as well as other minor oligosaccharides such as isofucose and 6-kestose.
Soy oligosaccharides are naturally found in soybeans and soy-based products such as soy milk, soy protein powder, and tofu. They can also be produced through the hydrolysis of soybean polysaccharides.
Glucomannan is a soluble fiber derived from the root of the konjac plant. It is a polysaccharide, made up of glucose and mannose, that can absorb large amounts of water and form a gel-like substance in the gut. Glucomannan has been used for various health purposes, including weight loss, blood sugar control, and reducing constipation.
There is typically one type of glucomannan, but it may vary in terms of purity, particle size, and processing method.
Glucomannan is found in various natural sources, including:
- Konjac root (Amorphophallus konjac)
- Konjac flour
- Shirataki noodles
- Some plant-based food products.
Chitooligosaccharides (COS) are a type of oligosaccharide, composed of chitin, a natural polysaccharide found in the exoskeletons of crustaceans and insects. The molecular weight of Chitooligosaccharides (COS) varies depending on the number of monomer units and can range from a few hundred to several thousand daltons. Chitooligosaccharides are also produced by partial hydrolysis of chitin through chitinases, enzymes that break down chitin.
Chitooligosaccharides have been shown to have prebiotic properties and have been used as a food ingredient for their health benefits.
Different types of COS can be produced by controlling the degree of hydrolysis of chitosan. Some common types include:
- Glucosamine oligosaccharides
- N-acetylglucosamine oligosaccharides
- Galactosamine oligosaccharides
- N-acetylgalactosamine oligosaccharides
Chitooligosaccharides (COS) can be produced through the degradation of chitin, a polysaccharide found in the shells of crustaceans, or through chemical synthesis. Some natural sources of COS include crab shells, shrimp shells, and squid pens. Additionally, COS can be found in fermented foods, such as kimchi and natto, as well as in dietary supplements.