Raffinose
Encyclopedia
Raffinose is a trisaccharide composed of galactose
, fructose
, and glucose
. It can be found in bean
s, cabbage
, brussels sprout
s, broccoli
, asparagus
, other vegetables, and whole grain
s. Raffinose can be hydrolyzed
to D-galactose and sucrose
by the enzyme α-galactosidase (α-GAL), an enzyme not found in the human digestive tract. α-GAL also hydrolyzes other α-galactosides such as stachyose
, verbascose, and galactinol, if present. The enzyme does not cleave β-linked galactose, as in lactose
.
The raffinose family of oligosaccharide
s (RFOs) are alpha-galactosyl derivatives of sucrose
, and the most common are the trisaccharide raffinose, the tetrasaccharide
stachyose, and the pentasaccharide verbascose. RFOs are almost ubiquitous in the plant
kingdom, being found in a large variety of seeds from many different families, and they rank second only to sucrose in abundance as soluble carbohydrates.
Humans and other monogastric animals (pig
s and poultry
) do not possess the α-GAL enzyme to break down RFOs and these oligosaccharides pass undigested through the stomach and upper intestine. In the lower intestine, they are fermented
by gas-producing bacteria
which do possess the α-GAL enzyme and make carbon dioxide
, methane
, and/or hydrogen
-- leading to the flatulence
commonly associated with eating beans and other vegetables. α-GAL is present in digestive aids such as the product Beano
.
Procedures concerning cryopreservation have used raffinose to provide hypertonicity for cell desiccation prior to freezing . Either raffinose or sucrose
is used as a base substance for sucralose
.
Galactose
Galactose , sometimes abbreviated Gal, is a type of sugar that is less sweet than glucose. It is a C-4 epimer of glucose....
, fructose
Fructose
Fructose, or fruit sugar, is a simple monosaccharide found in many plants. It is one of the three dietary monosaccharides, along with glucose and galactose, that are absorbed directly into the bloodstream during digestion. Fructose was discovered by French chemist Augustin-Pierre Dubrunfaut in 1847...
, and glucose
Glucose
Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...
. It can be found in bean
Bean
Bean is a common name for large plant seeds of several genera of the family Fabaceae used for human food or animal feed....
s, cabbage
Cabbage
Cabbage is a popular cultivar of the species Brassica oleracea Linne of the Family Brassicaceae and is a leafy green vegetable...
, brussels sprout
Brussels sprout
The Brussels sprout is a cultivar of wild cabbage grown for its edible buds. The leafy green vegetables are typically 2.5–4 cm in diameter and look like miniature cabbages. The sprout is Brassica oleracea, in the "gemmifera" group of the family Brassicaceae...
s, broccoli
Broccoli
Broccoli is a plant in the cabbage family, whose large flower head is used as a vegetable.-General:The word broccoli, from the Italian plural of , refers to "the flowering top of a cabbage"....
, asparagus
Asparagus
Asparagus officinalis is a spring vegetable, a flowering perennialplant species in the genus Asparagus. It was once classified in the lily family, like its Allium cousins, onions and garlic, but the Liliaceae have been split and the onion-like plants are now in the family Amaryllidaceae and...
, other vegetables, and whole grain
GRAIN
GRAIN is a small international non-profit organisation that works to support small farmers and social movements in their struggles for community-controlled and biodiversity-based food systems. Our support takes the form of independent research and analysis, networking at local, regional and...
s. Raffinose can be hydrolyzed
Hydrolysis
Hydrolysis is a chemical reaction during which molecules of water are split into hydrogen cations and hydroxide anions in the process of a chemical mechanism. It is the type of reaction that is used to break down certain polymers, especially those made by condensation polymerization...
to D-galactose and sucrose
Sucrose
Sucrose is the organic compound commonly known as table sugar and sometimes called saccharose. A white, odorless, crystalline powder with a sweet taste, it is best known for its role in human nutrition. The molecule is a disaccharide composed of glucose and fructose with the molecular formula...
by the enzyme α-galactosidase (α-GAL), an enzyme not found in the human digestive tract. α-GAL also hydrolyzes other α-galactosides such as stachyose
Stachyose
Stachyose is a tetrasaccharide consisting of two α--galactose units, one α--glucose unit, and one β--fructose unit sequentially linked as galgalglcfru. Stachyose is naturally found in numerous vegetables and plants.Stachyose is less sweet than sucrose, at about 28% on a weight basis...
, verbascose, and galactinol, if present. The enzyme does not cleave β-linked galactose, as in lactose
Lactose
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,...
.
The raffinose family of oligosaccharide
Oligosaccharide
An oligosaccharide is a saccharide polymer containing a small number of component sugars, also known as simple sugars...
s (RFOs) are alpha-galactosyl derivatives of sucrose
Sucrose
Sucrose is the organic compound commonly known as table sugar and sometimes called saccharose. A white, odorless, crystalline powder with a sweet taste, it is best known for its role in human nutrition. The molecule is a disaccharide composed of glucose and fructose with the molecular formula...
, and the most common are the trisaccharide raffinose, the tetrasaccharide
Tetrasaccharide
A tetrasaccharide is a carbohydrate which gives upon hydrolysis four molecules of the same or different monosaccharides. For example, stachyose upon hydrolysis gives one molecule each of glucose and fructose and two molecules of galactose. The general formula of a tetrasaccharide is typically...
stachyose, and the pentasaccharide verbascose. RFOs are almost ubiquitous in the plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
kingdom, being found in a large variety of seeds from many different families, and they rank second only to sucrose in abundance as soluble carbohydrates.
Humans and other monogastric animals (pig
Pig
A pig is any of the animals in the genus Sus, within the Suidae family of even-toed ungulates. Pigs include the domestic pig, its ancestor the wild boar, and several other wild relatives...
s and poultry
Poultry
Poultry are domesticated birds kept by humans for the purpose of producing eggs, meat, and/or feathers. These most typically are members of the superorder Galloanserae , especially the order Galliformes and the family Anatidae , commonly known as "waterfowl"...
) do not possess the α-GAL enzyme to break down RFOs and these oligosaccharides pass undigested through the stomach and upper intestine. In the lower intestine, they are fermented
Fermentation (biochemistry)
Fermentation is the process of extracting energy from the oxidation of organic compounds, such as carbohydrates, using an endogenous electron acceptor, which is usually an organic compound. In contrast, respiration is where electrons are donated to an exogenous electron acceptor, such as oxygen,...
by gas-producing bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
which do possess the α-GAL enzyme and make carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
, methane
Methane
Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...
, and/or hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
-- leading to the flatulence
Flatulence
Flatulence is the expulsion through the rectum of a mixture of gases that are byproducts of the digestion process of mammals and other animals. The medical term for the mixture of gases is flatus, informally known as a fart, or simply gas...
commonly associated with eating beans and other vegetables. α-GAL is present in digestive aids such as the product Beano
Beano (dietary supplement)
Beano is an enzyme-based dietary supplement that is used to reduce gas in the digestive tract, thereby improving digestion and reducing bloating, discomfort, and flatulence caused by gas. It contains the enzyme alpha galactosidase that breaks down oligosaccharides such as raffinose...
.
Procedures concerning cryopreservation have used raffinose to provide hypertonicity for cell desiccation prior to freezing . Either raffinose or sucrose
Sucrose
Sucrose is the organic compound commonly known as table sugar and sometimes called saccharose. A white, odorless, crystalline powder with a sweet taste, it is best known for its role in human nutrition. The molecule is a disaccharide composed of glucose and fructose with the molecular formula...
is used as a base substance for sucralose
Sucralose
Sucralose is an artificial sweetener. The majority of ingested sucralose is not broken down by the body and therefore it is non-caloric. In the European Union, it is also known under the E number E955. Sucralose is approximately 600 times as sweet as sucrose , twice as sweet as saccharin, and 3.3...
.