Anonaine is a bioactive

benzylisoquinoline Substitution of the heterocycle isoquinoline at the C1 position by a benzyl group provides 1‑benzylisoquinoline, the most widely examined of the numerous benzylisoquinoline structural isomers. The 1-benzylisoquinoline moiety can be identified wi ...

alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...

, present in members of the plant families

Magnoliaceae The Magnoliaceae () are a flowering plant family, the magnolia family, in the order Magnoliales. It consists of two genera: ''Magnolia'' and ''Liriodendron'' (tulip trees). Unlike most angiosperms, whose flower parts are in whorls (rings), the ...

and

Annonaceae The Annonaceae are a Family (biology), family of flowering plants consisting of trees, shrubs, or rarely lianas commonly known as the custard apple family or soursop family. With 108 accepted genera and about 2400 known species, it is the largest ...

It is named after the plant it was first extracted from, ''

Annona reticulata ''Annona reticulata'' is a small deciduous or semi-evergreen tree in the plant family Annonaceae and part of the Annonas group. It is best known for its fruit, called custard apple, a common name shared with fruits of several other species in t ...

'', which is commonly known as Anona.

Extraction from Annonaceae

The alkaloid was first isolated from the bark of the ''

''. It has since been found in ''

Annona squamosa ''Annona squamosa'' is a small, well-branched tree or shrub from the family Annonaceae that bears edible fruits called sugar-apples or . It tolerates a tropical lowland climate better than its relatives ''Annona reticulata'' and ''Annona cherimo ...

'', the leaves of ''Michelia'' × ''alba'', ''Fissistigma latifolium'' and ''Goniothalamus australis'', among many others. The compound may be obtained by dry roasting the bark of Annona reticulata and extracting with

methanol Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical and the simplest aliphatic alcohol, with the formula C H3 O H (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a ...

. The methanol is removed and the resulting syrup is then treated with

hydrochloric acid Hydrochloric acid, also known as muriatic acid, is an aqueous solution of hydrogen chloride. It is a colorless solution with a distinctive pungent smell. It is classified as a strong acid Acid strength is the tendency of an acid, symbol ...

and the insoluble salts filtered off. The filtrate can then made basic with NH₄OH and extracted with

diethyl ether Diethyl ether, or simply ether, is an organic compound in the ether class with the formula , sometimes abbreviated as (see Pseudoelement symbols). It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liq ...

. Shaking the extract with 5%

sodium hydroxide Sodium hydroxide, also known as lye and caustic soda, is an inorganic compound with the formula NaOH. It is a white solid ionic compound consisting of sodium cations and hydroxide anions . Sodium hydroxide is a highly caustic base and alkali ...

and retaining the organic layer removes the

phenol Phenol (also called carbolic acid) is an aromatic organic compound with the molecular formula . It is a white crystalline solid that is volatile. The molecule consists of a phenyl group () bonded to a hydroxy group (). Mildly acidic, it req ...

ic content of the extract. The hydrogen chloride salt is then obtained by mixing with

and recrystallized from diethyl ether. The

free base Free base (freebase, free-base) is the conjugate base (deprotonated) form of an amine, as opposed to its conjugate acid (protonated) form. The amine is often an alkaloid, such as nicotine, cocaine, morphine, and ephedrine, or derivatives thereo ...

can then be obtained. The anonaine content of ''Annona reticulata'' is approximately 0.12%, based on the weight of the starting dried bark.

Research

Traditional medicines

Anonaine is found in many species of ''Annonacae'', which have been used as traditional medicines for many years. For example, extracts of ''

'' have been used as treatments for epilepsy, dysentery, cardiac problems, worm infection, constipation, bacterial infection, fever and ulcers. It appears, however, that anonaine is not active in the treatment of many of these ailments. Studies into the bioactivity of anonaine have revealed various interesting pharmacological activities including antitumour, vasorelaxation, antioxidative, antiparasitic and antimicrobial effects, as well as having an effect on the central nervous system.

Anti-tumour properties

Anonaine is known to inhibit growth in human cervical cancer and human lung carcinoma H1299 cells ''

in vitro ''In vitro'' (meaning in glass, or ''in the glass'') studies are performed with microorganisms, cells, or biological molecules outside their normal biological context. Colloquially called "test-tube experiments", these studies in biology an ...

''. The mechanism by which anonaine induces apoptosis in these cells is believed to occur by several mechanisms: generation of

nitric oxide Nitric oxide (nitrogen oxide or nitrogen monoxide) is a colorless gas with the formula . It is one of the principal oxides of nitrogen. Nitric oxide is a free radical: it has an unpaired electron, which is sometimes denoted by a dot in its che ...

and reactive oxygen species, reduction in intracellular glutathione concentration, activation of caspases and apoptosis-related proteins, and damage to DNA.

References

{{Reflist Aporphine alkaloids Dibenzoquinolines

Extraction from Annonaceae

Research

Traditional medicines

Anti-tumour properties

See also

References