Vinca - Source, diagnostic characters, constituents, tests and uses

Vinca

Source, diagnostic characters, constituents, tests and uses

Objectives

At the end of this lecture, student will be able to

• Discuss the source, diagnostic characters, constituents, tests and uses of Vinca

Vinca

Synonym

• Vinca rosea, Periwinkle, Catharanthus

Biological Source

• Dried whole plant of Catharanthus roseus

Family

• Apocynaceae

Geographical Source

• Ornamental plant, US, European and Asian countries

• Indigenous to Madagasgar

Macroscopy

• Erect, pubescent herb with branched taproot

• Colour – Leaves – green, roots pale grey, flowers – violet, pink white or carmine red

• Leaves – simple, petiolate, ovate – oblong, entire, acute apex

• Flowers – bractate, hermaphrodite, 2-3 cymose axillary cluster

• Fruits - follicle

• Odour - Characteristics

• Taste - Bitter

Microscopy

Vinca - Powder characters

Organoleptic characters: Taste, Colour, odour, taste

Active Constituents:

• Large number of alkaloids are present

• 20 dimeric indole – dihydroindole alkaloids – Vincristine, vinblastine – Oncolytic activity

• Other alkaloids – ajmalicine, serpentine, lochnerine, tetrahydroalstonine

Chemical tests:

• General chemical tests for alkaloids

• Dragendroff’s test

• Mayer’s test

• Wagner’s test

• Hager’s test

Uses:

Vincristine	Vinblastine
Acute leukemia in children	Hodgkin’s disease
Wilm’s tumor	Choriocarcinoma
Cancer of mammary glands	Cancer of mammary glands
Cervical cancer	Lymphocytic lymphoma
Rhabdomyosarcoma	Advanced testicular cancer
Neuroblastoma	Kaposis’s sarcoma
Lung cancer
Reticulum cell sarcoma

Substitutes

• C. ovalis

• C. longifolius

• C. pussilus