Coca: Biological Source, Medicinal Uses, Morphological features and MCQ

COCA

1. Biological source:

• It belongs to the erythroxylaceae.
• The botanical name of coca is Erythroxylon coca lam.
• The biological source of coca is its dried leaves.
• It is also known as cuca,cocaine,folium cocae and bolivian coca.

2. Morphological features:

• The color of leaves are brownish to green.
• The shape of leaves are oval.
• Leaves are glabrous.
• It have a bitter taste.
• It is 3-8 cm long and 1.5-4 cm wide.
• Erythroxylon truxillense ,another species of coca contain elliptical shaped leaves and they are pale green in color.
• This plant resembles a blackthorn bush having height upto 2-3 m .
• The branches of coca are straight .
• Leaves contain a green tint and they are taper at the extremities.
• In leaf an areolated portion is bounded by two longitudinal curved lines, one line on each side of the midrib and more conspicuous on the under face of the leaf.
• Flowers are small in size and they are disposed in little clusters on short stalks.
• Corolla of flowers of is composed of five yellowish – white petals.
• The of anthers is heart –shaped and pistil contain 3 carples united to form a three-chambered ovary.
• At maturation flowers turn into red berries.

3. Chemical constituents:

• The major chemical constituent of coca is alkaloids and it is about 0.7-1.5% of total alkaloids.
• It is consist of cocaine, cinnamyl cocaine and alpha-truxilline or cocamine.
• In java coca, tropacocaine and 4 crystalline glucosides are present in addition with other chemical constituents.
• Cinnamylcocaine is the chief chemical constituent of coca.
• Hygrine, hygroline, cuscohygrine , dihydrocuscohygrine and tropacocaine also isolated from the leaves of coca.
• They also contain cocatannica acid.
• 1- hydroxytropacocaine is the largely isolated chemical constituent from the E. novogranatense species.
• Essential oil also present in coca .
•

4. Uses:

• The major chemical constituent of coca, cocaine has stimulant action on CNS.
• Leaves are used to relieve from hunger and fatigue.
• Coca leaves are used as stimulant of cerebral area and muscle stimulant.
• It is especially used during convalescence, to get rid from nausea, vomiting and pains of stomach without upsetting the digestion.
• It also has local anesthetic action on skin and mucous membrane.
• It is used as dental anesthesia and in minor local surgery of eye, ear, nose and throat.
• The chemical structure of cocaine lead many synthetic anesthetics like anesthesia, Novocain and stovain.

5. Adulterants:

Jaborandi leaves are the common adulterants of coca leaves.

6. MULTIPLE CHOICE QUESTIONS:

1. What is the botanical name of coca?
(a) Schizzanthus wisetonensis
(b) Dianthus barbatus
(c) Lupinus texensis
(d) Erythroxylon coca Lam.

2. What is the biological source of coca?
(a) Root
(b) Leaves
(c) Flowers
(d) Bark

3. Match the following with respect to the chemical constituents of the plants.
I. Vinca                                                  A. ephedrine
II. Ephedra                                           B. Vincristine
III. Nux vomica                                    C. Strychnine
IV. Coca                                                 D. cinnamylcocaine

(a) I-A,II-B,III-C,IV-D
(b) I-B,II-A,III-C,IV-D
(c) I-C,II-D,III-A,IV-B
(d) I-D,II-C,III-B,IV-A

4. Choose incorrect statement with respect to the medicinal uses of plants.
i. Coca is used to treat jaundice.
ii. Cinchona is used to treat malaria.
iii. Opium is used to treat constipation.
iv. Vinca is used to treat lymphomas.
(a) Only i
(b) Both i and ii
(c) Only iii
(d) Both i and iv

5. What is the common adulterant of coca leaves?
(a) Gypsum
(b) Indigo dye
(c) Methylene blue dye
(d) Jaborandi leaves

6. What is the shape of leaves of coca?
(a) Palm shape
(b) Needle shape
(c) Oval shape
(d) Linear shape

7. Leaves of coca are
(a) Glabrous
(b) Brownish to green in color
(c) Taper at the extremities
(d) All of the above

8. What are the chemical constituents of coca?
(a) Cocaine
(b) Cinnamyl cocaine
(c) Cocamine
(d) All of the above

9. What is the chief chemical constituent of coca?
(a) Cephaline
(b) Cinnamyl cocaine
(c) Strychnine
(d) Pristine

10. Coca is used to
(a) Relieve hunger and fatigue
(b) As stimulant of cerebral area
(c) Anesthesia
(d) All of the above

ANSWERS:

1. (d)
2. (b)
3. (b)
4. (a)
5. (d)
6. (c)
7. (d)
8. (d)
9. (b)
10. (d)

REFERENCE:

Evans W.C, Editors. Trease and Evans Pharmacognosy. New York, Saunders Elsevier; 2009, p. 368-369.