Rebaudioside A (sometimes shortened to "Reb A") is a
steviol glycoside
Steviol glycosides are the chemical compounds responsible for the sweet taste of the leaves of the South American plant ''Stevia rebaudiana'' (Asteraceae) and the main ingredients (or chemical precursor, precursors) of many sugar substitute, swee ...
from the leaves of ''
Stevia rebaudiana
''Stevia rebaudiana'' is a plant species in the genus ''Stevia (genus), Stevia'' of the family Asteraceae. It is commonly known as candyleaf, sweetleaf or sugarleaf.
It is a small seasonal plant which grows to a height of . It has elongated lea ...
'' that is 240 times sweeter than
sugar
Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose
Glucose is a sugar with the Chemical formula#Molecular formula, molecul ...
.
Rebaudioside A is the sweetest and most stable steviol glycoside, and is less bitter than
stevioside
Stevioside is a glycoside derived from the stevia plant, which can be used as a sweetener. Evidence of benefit is lacking for long-term effects on weight loss and heart disease risks.
Origin
Stevioside is the main sweetener (along with rebaud ...
.
''Stevia'' leaves contain 9.1% stevioside and 3.8% rebaudioside A.
The glycoside contains only
glucose
Glucose is a sugar with the Chemical formula#Molecular formula, molecular formula , which is often abbreviated as Glc. It is overall the most abundant monosaccharide, a subcategory of carbohydrates. It is mainly made by plants and most algae d ...
(to the exclusion of other commonly found
monosaccharides
Monosaccharides (from Greek ''monos'': single, '' sacchar'': sugar), also called simple sugars, are the simplest forms of sugar and the most basic units (monomers) from which all carbohydrates are built.
Chemically, monosaccharides are polyhydr ...
) as its monosaccharide
moieties. It contains four glucose molecules in total with the central glucose of the triplet connected to the main
steviol structure at its
hydroxyl group
In chemistry, a hydroxy or hydroxyl group is a functional group with the chemical formula and composed of one oxygen atom covalently bonded to one hydrogen atom. In organic chemistry, alcohols and carboxylic acids contain one or more hydroxy ...
, and the remaining glucose at its
carboxyl group
In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an R-group. The general formula of a carboxylic acid is often written as or , sometimes as with R referring to an organyl group (e.g. ...
forming an
ester
In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distin ...
bond.
References
Glucosides
Vinylidene compounds
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