Galactooligosaccharides
Encyclopedia
Galacto-oligosaccharides (GOS), also known as oligogalactosyllactose, oligogalactose, oligolactose or transgalactooligosaccharides (TOS), belong, because of their indigestible nature, to the group of prebiotics
. Prebiotics are defined as non-digestible food ingredients that beneficially affect the host by stimulating the growth and/or activity of beneficial bacteria in the colon. GOS occurs in commercial available products such as food for both infants and adult, ranging from infant formula
to biscuits to food for the critical ill.
, a component of bovine milk. They do not occur naturally in human milk.
A range of factors come into play when determining the yield, style and type of GOS produced. These factors include:
GOS generally comprise a chain of galactose units that arise through consecutive transgalactosylation reactions, with a terminal glucose unit. However, where a terminal galactose unit is indicated, hydrolysis of GOS formed at an earlier stage in the process has occurred.
The degree of polymerization of GOS can vary quite markedly, ranging from 2 to 8 monomeric units.
Yakult is producing three GOS product: Oligomate 55 in syrup form, Oligomate 55P in powder form and TOS-100 a purified version of 99% oligosaccharide content. Nissin is producing Cup-Oligo in syrup (Cup-Oligo H70) and powder format (Cup-Oligo P) and Snow Brand produces GOS that is incorporated into its infant milk formula P7L, without offering sales outside its organization.
In Europe, Friesland Food Domo is offering Vivinal GOS in a syrup format containing 57% oligosaccharides on dry matter and in a powder format containing 29% oligosaccharides on dry matter. Clasado Ltd is offering a powder GOS product, Bimuno, with 52% galacto-oligosaccharide content on dry matter, as well as a syrup and pastille versions of that product.
Besides the differences in the purity amongst the commercially offered products, there are differences also in the linkages of the oligosaccharide chain due to the different enzymes used in their production. This can have a direct impact on their potential to affect host's physiology
and health. The Oligomate range is produced with enzymes originating from Aspergillus oryzae offering mainly β 1-6 linkages, the Bimuno product is produced using enzymes from a probiotic
Bifidobacterium bifidum and contains mainly β 1-3 linkages whilst Cup-Oligo and Vivinal offer mainly β 1-4 linkages as a result of the activity of enzymes from Bacillus circulans for the latter and Cryptococcus laurentii for the former GOS product. Yakult is also considering dual enzymes systems combining the activity of enzymes from A. oryzae and B. circulans to produce GOS mixtures of β 1-4 and β 1-6 linkages.
s. Therefore they reach the colon virtually intact.The human intestine contains about 300-500 different species of bacteria that can be divided into health-promoting ones, like Bifidobacteria and Lactobacilli and into harmful ones like Clostridia
. Galacto-Oligosaccharides (GOS) are classified as prebiotics, defined as non-digestible food ingredients that beneficially affect the host by stimulating the growth and/or activity of beneficial bacteria in the colon. The increased activity of these health-promoting bacteria results in a number of health-related benefits both directly by the bacteria themselves or indirectly by the organic acid
s they produce via fermentation. Examples of potential health-promoting benefits are inhibition of the growth of harmful bacteria, stimulation of immune functions, absorption of essential nutrient
s and syntheses of certain vitamins.
However, not all GOS result in the same effect due to differences in their structures as explained above. For example, consumption of Bimuno by humans was shown to result in significantly higher bifidogenic effect than consumption of Vivinal GOS
that provides defence against ingested toxins and pathogenic bacteria. A well-balanced gut microflora is thought to play a particularly important role in the natural defence of the human body. Galacto-oligosaccharides support natural defences of the human body via the gut microflora
,
indirectly by increasing a number of good bacteria in the gut and inhibiting the binding or survival of Escherichia coli, Salmonella Typhimurium
and Clostridia to the body, reducing the chances of getting infected,
and directly by interaction with immune cells
. For example, in infants the usage of galacto-oligosaccharides has been shown to have a potential role in allergy prevention and reduction of infectious disease
s. Galactooligosaccharide supplementation has also been shown to reduce symptoms of gastrointestinal dysfunction and reduce the number of days with cold or flu in stressed undergraduate students undergoing exams.
it has been demonstrated that administration of galacto-oligosaccharides results in more efficiently absorbed calcium and increased bone density
, indicating the prevention of bone losses.
. For these individuals, consumption of galactooligosaccharides can offer relief to their constipation. For these individuals consumption of Vivinal GOS can offer relief of their complaints, as it has been shown to increase frequency of defecation.
Prebiotic (nutrition)
Prebiotics are non-digestible food ingredients that stimulate the growth and/or activity of bacteria in the digestive system in ways claimed to be beneficial to health. They were first identified and named by Marcel Roberfroid in 1995. As a functional food component, prebiotics, like probiotics,...
. Prebiotics are defined as non-digestible food ingredients that beneficially affect the host by stimulating the growth and/or activity of beneficial bacteria in the colon. GOS occurs in commercial available products such as food for both infants and adult, ranging from infant formula
Infant formula
Infant formula is a manufactured food designed and marketed for feeding to babies and infants under 12 months of age, usually prepared for bottle-feeding or cup-feeding from powder or liquid . The U.S...
to biscuits to food for the critical ill.
Chemistry
The composition of the galacto-oligosaccharide fraction varies in chain length and type of linkage between the monomer units. Galacto-oligosaccharides are produced through the enzymatic conversion of lactoseLactose
Lactose is a disaccharide sugar that is found most notably in milk and is formed from galactose and glucose. Lactose makes up around 2~8% of milk , although the amount varies among species and individuals. It is extracted from sweet or sour whey. The name comes from or , the Latin word for milk,...
, a component of bovine milk. They do not occur naturally in human milk.
A range of factors come into play when determining the yield, style and type of GOS produced. These factors include:
- The enzymeEnzymeEnzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
source - The feeding stock (LactoseLactoseLactose is a disaccharide sugar that is found most notably in milk and is formed from galactose and glucose. Lactose makes up around 2~8% of milk , although the amount varies among species and individuals. It is extracted from sweet or sour whey. The name comes from or , the Latin word for milk,...
) concentration - The origins of the lactose
- The process involved (e.g. free or immobilized enzyme)
- The conditions impacting the processing situation
- The medium composition
GOS generally comprise a chain of galactose units that arise through consecutive transgalactosylation reactions, with a terminal glucose unit. However, where a terminal galactose unit is indicated, hydrolysis of GOS formed at an earlier stage in the process has occurred.
The degree of polymerization of GOS can vary quite markedly, ranging from 2 to 8 monomeric units.
Commercially available GOS
GOS have been used as food ingredients in Japan and Europe for at least 30 years and their application is currently expanding rapidly. At present, Japanese companies still dominate worldwide galacto-oligosaccharide production and development activity, although, European interest in GOS based products is increasing with several companies currently producing or planning to produce GOS mixtures. In contrast, GOS production in the USA at present remains negligible. The major companies manufacturing GOS are still located in Japan. Yakult Honsha (Tokyo, Japan), Nissin Sugar Manufacturing Company (Tokyo, Japan) and Snow Brand Milk Products (Tokyo, Japan) together with Friesland Foods Domo (ex Borculo Domo ingredients) in the Netherlands and Clasado Ltd in the UK are the main manufacturers. Most of the manufacturers produce several classes of products in terms of GOS purity in either syrup and/or powder format.Yakult is producing three GOS product: Oligomate 55 in syrup form, Oligomate 55P in powder form and TOS-100 a purified version of 99% oligosaccharide content. Nissin is producing Cup-Oligo in syrup (Cup-Oligo H70) and powder format (Cup-Oligo P) and Snow Brand produces GOS that is incorporated into its infant milk formula P7L, without offering sales outside its organization.
In Europe, Friesland Food Domo is offering Vivinal GOS in a syrup format containing 57% oligosaccharides on dry matter and in a powder format containing 29% oligosaccharides on dry matter. Clasado Ltd is offering a powder GOS product, Bimuno, with 52% galacto-oligosaccharide content on dry matter, as well as a syrup and pastille versions of that product.
Besides the differences in the purity amongst the commercially offered products, there are differences also in the linkages of the oligosaccharide chain due to the different enzymes used in their production. This can have a direct impact on their potential to affect host's physiology
Physiology
Physiology is the science of the function of living systems. This includes how organisms, organ systems, organs, cells, and bio-molecules carry out the chemical or physical functions that exist in a living system. The highest honor awarded in physiology is the Nobel Prize in Physiology or...
and health. The Oligomate range is produced with enzymes originating from Aspergillus oryzae offering mainly β 1-6 linkages, the Bimuno product is produced using enzymes from a probiotic
Probiotic
Probiotics are live microorganisms thought to be beneficial to 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"...
Bifidobacterium bifidum and contains mainly β 1-3 linkages whilst Cup-Oligo and Vivinal offer mainly β 1-4 linkages as a result of the activity of enzymes from Bacillus circulans for the latter and Cryptococcus laurentii for the former GOS product. Yakult is also considering dual enzymes systems combining the activity of enzymes from A. oryzae and B. circulans to produce GOS mixtures of β 1-4 and β 1-6 linkages.
Health benefits
Because of the configuration of their osidic bonds, galactooligosaccharides resist hydrolysis by salivary and intestinal digestive enzymeDigestive enzyme
'Digestive enzymes' are enzymes that break down polymeric macromolecules into their smaller building blocks, in order to facilitate their absorption by the body. Digestive enzymes are found in the digestive tract of animals where they aid in the digestion of food as well as inside the cells,...
s. Therefore they reach the colon virtually intact.The human intestine contains about 300-500 different species of bacteria that can be divided into health-promoting ones, like Bifidobacteria and Lactobacilli and into harmful ones like Clostridia
Clostridia
The Clostridia are a class of Firmicutes, including Clostridium and other similar genera. They are distinguished from the Bacilli by lacking aerobic respiration. They are obligate anaerobes and oxygen is toxic to them. Species of the genus Clostridium are all Gram-positive and have the ability to...
. Galacto-Oligosaccharides (GOS) are classified as prebiotics, defined as non-digestible food ingredients that beneficially affect the host by stimulating the growth and/or activity of beneficial bacteria in the colon. The increased activity of these health-promoting bacteria results in a number of health-related benefits both directly by the bacteria themselves or indirectly by the organic acid
Organic acid
An organic acid is an organic compound with acidic properties. The most common organic acids are the carboxylic acids, whose acidity is associated with their carboxyl group –COOH. Sulfonic acids, containing the group –SO2OH, are relatively stronger acids. The relative stability of the conjugate...
s they produce via fermentation. Examples of potential health-promoting benefits are inhibition of the growth of harmful bacteria, stimulation of immune functions, absorption of essential nutrient
Essential nutrient
An essential nutrient is a nutrient required for normal body functioning that either cannot be synthesized by the body at all, or cannot be synthesized in amounts adequate for good health , and thus must be obtained from a dietary source...
s and syntheses of certain vitamins.
Stimulating health-promoting bacteria
Galactooligosacchairdes have been shown to be an excellent source for health-promoting bacteria such as Bifidobacteria and Lactobacilli. Many studies with infants and adults have shown that foods or drinks enriched with galacto-oligosaccharides result in a significant increase in Bifidobacteria. In comparison with other oligosaccharides, the bifidogenicity for galactooligosacchairdes was strongly shown.However, not all GOS result in the same effect due to differences in their structures as explained above. For example, consumption of Bimuno by humans was shown to result in significantly higher bifidogenic effect than consumption of Vivinal GOS
Support of natural defences
Human gut microbiota play a key role in the intestinal immune system, in maintaining a disease-free state. The gut and immune system form a complex structureComplex manifold
In differential geometry, a complex manifold is a manifold with an atlas of charts to the open unit disk in Cn, such that the transition maps are holomorphic....
that provides defence against ingested toxins and pathogenic bacteria. A well-balanced gut microflora is thought to play a particularly important role in the natural defence of the human body. Galacto-oligosaccharides support natural defences of the human body via the gut microflora
Gut flora
Gut flora consists of microorganisms that live in the digestive tracts of animals and is the largest reservoir of human flora. In this context, gut is synonymous with intestinal, and flora with microbiota and microflora....
,
indirectly by increasing a number of good bacteria in the gut and inhibiting the binding or survival of Escherichia coli, Salmonella Typhimurium
Salmonella enterica
Salmonella enterica is a rod-shaped flagellated, facultative anaerobic, Gram-negative bacterium, and a member of the genus Salmonella.- Epidemiology :...
and Clostridia to the body, reducing the chances of getting infected,
and directly by interaction with immune cells
White blood cell
White blood cells, or leukocytes , are cells of the immune system involved in defending the body against both infectious disease and foreign materials. Five different and diverse types of leukocytes exist, but they are all produced and derived from a multipotent cell in the bone marrow known as a...
. For example, in infants the usage of galacto-oligosaccharides has been shown to have a potential role in allergy prevention and reduction of infectious disease
Infectious disease
Infectious diseases, also known as communicable diseases, contagious diseases or transmissible diseases comprise clinically evident illness resulting from the infection, presence and growth of pathogenic biological agents in an individual host organism...
s. Galactooligosaccharide supplementation has also been shown to reduce symptoms of gastrointestinal dysfunction and reduce the number of days with cold or flu in stressed undergraduate students undergoing exams.
Improvement of mineral absorption
While calcium is necessary for processes such as bone development, only part of the calcium present in the diet is available for absorption. GOS can contribute to the provision of sufficient levels of calcium as it stimulates its absorption. In humans it has been demonstrated that the consumption of GOS significantly increases calcium absorption. In animal studiesAnimal testing
Animal testing, also known as animal experimentation, animal research, and in vivo testing, is the use of non-human animals in experiments. Worldwide it is estimated that the number of vertebrate animals—from zebrafish to non-human primates—ranges from the tens of millions to more than 100 million...
it has been demonstrated that administration of galacto-oligosaccharides results in more efficiently absorbed calcium and increased bone density
Bone density
Bone density is a medical term normally referring to the amount of mineral matter per square centimeter of bones. Bone density is used in clinical medicine as an indirect indicator of osteoporosis and fracture risk.This medical bone density is not the true physical "density" of the bone, which...
, indicating the prevention of bone losses.
Relief of constipation
Constipation is a frequent problem, particularly among the elderly and pregnant womenPregnancy
Pregnancy refers to the fertilization and development of one or more offspring, known as a fetus or embryo, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets...
. For these individuals, consumption of galactooligosaccharides can offer relief to their constipation. For these individuals consumption of Vivinal GOS can offer relief of their complaints, as it has been shown to increase frequency of defecation.