Betulin is an abundant, naturally occurring
triterpene. It is commonly isolated from the
bark
Bark may refer to:
* Bark (botany), an outer layer of a woody plant such as a tree or stick
* Bark (sound), a vocalization of some animals (which is commonly the dog)
Places
* Bark, Germany
* Bark, Warmian-Masurian Voivodeship, Poland
Arts, ...
of
birch trees. It forms up to 30% of the dry weight of
silver birch bark. It is also found in
birch sap
Birch sap, birch water or birch juice is the sap directly tapped from birch trees, ''Betula pubescens'' (white birch), ''Betula pendula'' (silver birch), '' Betula lenta'', ''Betula papyrifera'', and '' Betula fontinalis''.
Birch sap may be consu ...
. ''
Inonotus obliquus
''Inonotus obliquus'', commonly called chaga (a Latinisation of the Russian word ''чага''), is a fungus in the family Hymenochaetaceae. It is parasitic on birch and other trees. The sterile conk is irregularly formed and resembles burnt c ...
'' and
red alder also contain betulin.
The compound in the bark gives the tree its white color which appears to protect the tree from mid-winter overheating by the sun. As a result, birches are some of the northernmost occurring deciduous trees. It can be converted to
betulinic acid
Betulinic acid is a naturally occurring pentacyclic triterpenoid which has antiretroviral, antimalarial, and anti-inflammatory properties, as well as a more recently discovered potential as an anticancer agent, by inhibition of topoisomerase. I ...
(the
alcohol
Alcohol most commonly refers to:
* Alcohol (chemistry), an organic compound in which a hydroxyl group is bound to a carbon atom
* Alcohol (drug), an intoxicant found in alcoholic drinks
Alcohol may also refer to:
Chemicals
* Ethanol, one of sev ...
group replaced by a
carboxylic acid
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 or , with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic ...
group), which is biologically more active than betulin itself.
History
Betulin was discovered in 1788 by German-Russian chemist
Johann Tobias Lowitz.
Chemistry
Chemically, betulin is a triterpenoid of
lupane structure. It has a pentacyclic ring structure, and hydroxyl groups in positions C3 and C28.
Biological activities
Preliminary ''in vitro'' studies have shown that betulin demonstrates anti-cancer properties against a variety of
tumors. Betulin causes some types of tumor cells to start a process of self-destruction called
apoptosis
Apoptosis (from grc, ἀπόπτωσις, apóptōsis, 'falling off') is a form of programmed cell death that occurs in multicellular organisms. Biochemical events lead to characteristic cell changes (morphology) and death. These changes incl ...
, and can slow the growth of several types of tumor cells.
In another study, betulin inhibited the maturation of
sterol regulatory element-binding protein (SREBPs). Inhibition of SREBP by betulin decreased the biosynthesis of
cholesterol and
fatty acids.
In vivo, betulin ameliorated diet-induced
obesity, decreased the
lipid contents in serum and tissues, and increased
insulin sensitivity. Furthermore, betulin reduced the size and improved the stability of
atherosclerotic plaques
Atherosclerosis is a pattern of the disease arteriosclerosis in which the wall of the artery develops abnormalities, called lesions. These lesions may lead to narrowing due to the buildup of atheromatous plaque. At onset there are usually no sy ...
.
used
red alder bark to treat
poison oak,
insect bites, and
skin irritations.
Blackfoot Indians
The Blackfoot Confederacy, ''Niitsitapi'' or ''Siksikaitsitapi'' (ᖹᐟᒧᐧᒣᑯ, meaning "the people" or " Blackfoot-speaking real people"), is a historic collective name for linguistically related groups that make up the Blackfoot or Bla ...
used an
infusion made from the bark of red alder to treat
lymphatic disease
Lymphatic disease is a class of disorders which directly affect the components of the lymphatic system.
Examples include Castleman's disease and lymphedema.
__TOC__ Types
Diseases and disorder
Hodgkin's Disease/Hodgkin's Lymphoma
Hodgkin lymphoma ...
s and
tuberculosis.
See also
*
Abietic acid
*
Stanol ester
*
Phytosterols
References
{{Reflist
Triterpenes