
Isoflavonoids are a class of
flavonoid
Flavonoids (or bioflavonoids; from the Latin word ''flavus'', meaning yellow, their color in nature) are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans.
Chemically, flavonoids ...
phenolic compounds, many of which are biologically active. Isoflavonoids and their derivatives are sometimes referred to as
phytoestrogen
A phytoestrogen is a plant-derived xenoestrogen (a type of estrogen produced by organisms other than humans) not generated within the endocrine system, but consumed by eating plants or manufactured foods. Also called a "dietary estrogen", it ...
s, as many isoflavonoid compounds have biological effects via the
estrogen receptor
Estrogen receptors (ERs) are proteins found in cell (biology), cells that function as receptor (biochemistry), receptors for the hormone estrogen (17β-estradiol). There are two main classes of ERs. The first includes the intracellular estrogen ...
.
Medically, isoflavonoids and related compounds have been used in many
dietary supplement
A dietary supplement is a manufactured product intended to supplement a person's diet by taking a pill (pharmacy), pill, capsule (pharmacy), capsule, tablet (pharmacy), tablet, powder, or liquid. A supplement can provide nutrients eithe ...
s but the medical and scientific community is generally skeptical of their use. Recently, some natural isoflavonoids have been identified as toxins, including
biliatresone which may cause
biliary atresia
Biliary atresia, also known as extrahepatic ductopenia and progressive obliterative cholangiopathy, is a childhood disease of the liver in which one or more bile ducts are abnormally narrow, blocked, or absent. It can be congenital or acquired. ...
when infants are exposed to the plant product.
The isoflavonoid group is broad, and includes many structurally similar groups, including:
*
isoflavones
*
isoflavanones
* isoflavans
*
pterocarpans
*
rotenoids
Isoflavonoids are derived from the flavonoid biosynthesis pathway via
liquiritigenin or
naringenin.
Chemical makeup
While
flavonoids (in the narrow sense) have the 2-phenylchromen-4-one backbone, isoflavonoids have the 3-phenylchromen-4-one backbone with no hydroxyl group substitution at position 2 (case of the isoflavones) or the 3-phenylchroman (isoflavan) backbone (case of isoflavanes, such as
equol).
See also
*
Daidzein
Daidzein (7-hydroxy-3-(4-hydroxyphenyl)-4H-chromen-4-one) is a naturally occurring compound found exclusively in soybeans and other legumes, and structurally belongs to a class of compounds known as isoflavones. Daidzein and other isoflavones a ...
*
Equol
*
Flavonoid
Flavonoids (or bioflavonoids; from the Latin word ''flavus'', meaning yellow, their color in nature) are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans.
Chemically, flavonoids ...
*
Genistein
Genistein (C15H10O5) is a plant-derived, aglycone isoflavone. Genistein has the highest content of all isoflavones in soybeans and soy products, such as tempeh. As a type of phytoestrogen, genistein has estrogenic activity in vitro; consequ ...
*
Glycitein
Glycitein is an O-methylated isoflavone which accounts for 5-10% of the total isoflavones in soy food products. Glycitein is a phytoestrogen with weak estrogenic activity, comparable to that of the other soy isoflavones.
Glycitin (glycitein 7-' ...
*
Homoisoflavonoids, related molecules with a 16-carbon skeleton
*
Isoflavone
Isoflavones are a type of naturally-occurring isoflavonoids, many of which act as phytoestrogens in mammals. Isoflavones occur in many plant species, but are especially high in soybeans.
Although isoflavones and closely-related phytoestrogens ar ...
References
{{GABAergics