ALKALOIDS: VINCA

 ALKALOIDS: Vinca

SYNONYMS,BIOLOGICAL SOURCE,FAMILY,GEOGRAPHICAL SOURCE,MOCROSCOPICAL CHARACTERS,MACROSCOPICAL CHARACTERS,CULTIVATION AND COLLECTION,MICROSCOPY,CHEMICAL TEST,STRUCTURE AND USES

• Synonyms of Vinca: Catharanthus, Periwinkle ,Vinca rosea , Madagascar , Barmasi.
• Biological source of Vinca: It consists of dried whole plant of Catharanthus roseus  or Vinca rosea.
• Family of Vinca: Apocynaceae.
• Geographical source of Vinca: The plant is a native of Madagascar and is found in manytropical and subtropical countries especially in India, Australia, South Africa and North and South America. The plant is cultivated as garden plant in Europe and India
• Macroscopical characters of Vinca
  
  
  

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

        Odour: Characteristic
        Taste: Bitter
         Features: The plant is an erect, pubescent herb having branched                                                taproots.
         Leaves: Simple, petiolate, ovate, or oblong and glossy.
         Flowers: Bracteate, pedicellate, complete, and hermaphrodite.
         Fruits: Follicles with many black seeds.

Cultivation and Collection

It require dry or moist soil and can tolerate drought.

Ø     It is cultivated either by directly sowing the seeds or sowing the seeds in nursery.

Ø    Nursery sowing method is found to be economical and the fresh seeds are sown nursery in the month of February or March.

Ø  The seedlings attain a height of 5-8 cm after two months and then they are transplanted in to the field at a distance of 45 cm x 30 cm

Ø  In order to collect the whole plant, the stems are first cut about 10 cmabove the grounds and the leaves, seeds, stems are separated and dried.

Ø  The roots are collected by plugging which are later washed and dried under shade and packed.

 

 Microscopy

1.  Epidermis is a single layer of rectangular cells covered with thick cuticle. It consists of uni-cellular covering trichome and cruciferous stomata.
2.  Palisade parenchyma cells are present just below the upper epidermis
3.  Midrib region two to three layers of collenchyma is present, both below the upper epidermis and above the lower epidermis
4.  Vascular bundle consisting of xylem and phloem is present in the middle of midrib region.

CHEMICAL TESTS:

1.Mayer's test:

Mayer's reagent (freshly prepared mixture of mercuric chloride (1.36gm) and potassium iodide (5.00gm) in 10 ml of water) is added to the 3 ml of extract.

Gives creamy precipitates.

2. Hager's test:

Picric acid solution is added to the extract.

It gives yellow precipitates.

CHEMICAL STRUCTURE:

1.Chemical Vinblastin

2.Vincristine

Uses:

1. Vinblastin is an antitumour alkaloid used in the treatment of Hodgkin's disease
2. Vincristine is used to treat leukaemia in children
3. It may also be used as a gargle
4. The flowers of the Periwinkle are gently purgative
5. It is stated, is excellent as a gentle laxative for children