Vinca - Alkaloids - Pharmacognosy and phytochemistry 2

 Synonyms: Catharanthus, Periwinkle

 Biological source: It consists of dried whole plant of Catharanthus roseus L or Vinca rosea.

 Family: Apocynaceae.

 Geographical source: It is indigenous to Madagascar and cultivated in South Africa,India, USA, Europe and Australia.

Cultivation and Collection:

 It grows well at an altitude upto 500 mt. This plant is found all over India but grown well in tropical and subtropical areas (like southern and north eastern part) of India. It does not require any particular type of soil. It grows well in light sandy soil which should be rich in humus content. 

Macroscopical characters:

 Colour : Green (Leaves), Pale grey (Roots),Purple or pinkish white or caramine red (Flowers)

Odour : Characteristic

 Taste : Bitter

 Other features : The plant is an erect, pubescent herb having branched tap root.

 Leaves : Simple, petiolate, ovate or oblong and glossy.

 Flowers : Bracteate, pedicellate, complete and hermaphrodite.

 Fruits : Follicles with many black seeds.

Constituents:

150 alkaloids have now been isolated from Catharanthus roseus e.g. ajmalicine, serpentine, tetrahydrolalstonin and lochnerine etc.

The plant contain large number of indole alkaloids, out of them about 20 dimeric indole dihydroindole alkaloids contains antineoplastic activity including vincristine and vinblastine. These two alkaloids are much significant.

Uses:

Vinca plant is used to extract alkaloids like vincristine, vinblastine and ajmalicine.

Vincristine sulphate acts on mitotic cell division of metaphase and arrest the cell for further division; hence used as an antineoplastic drug whereas vinblastine sulphate acts on mitosis of metaphase and interferes in amino acid metabolism. It suppresses the immunity and uses in hodgkin’s disease, lymphoma and  choriocarcinoma treatment. 

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