Dioscorea, Biological sources, morphology, chemical constituents, adulterants and uses + MCQ

Dioscorea, Biological sources, morphology, chemical constituents, adulterants and uses + MCQ

Ginseng, Dioscorea and Sarsaparilla are belong to class of tetracyclic triterpenoid saponin.


Synonyms :- 

Yam, Rheumatism root

Biological source :- 

 Dioscorea consists of dried rhizome of various species of Dioscorea deltoidea (6-7%Diosgenin), Dioscorea Composite ( 4-5% Diosgenin), Dioscorea Floribunda (3-5%Diosgenin). Family :- Dioscoreaceae

Geographical Source :-

It is mainly found in North America, Mexico, India (Hima-layas from Kashmir and Punjab up to an altitude of 3,000 m), Nepal and China.

Morphology :-  Colour :-  Slightly Brown Odour :- Odourless Taste :-  Bitter & Acrid Size :-  Varies depending on the age of the rhizome

Microscopy :-

The transverse section of the drug when observed under the microscope shows the absence of epidermis, the cork is made up of few layers and next to cork it has corical parenchymatous tissue with thin wall. The major part of the drug is occupied by stele and consists of collateral type of fibrovascular bundles. The drug has indistinguishable endodermis and pericycle.

Chemical Constitution :-

Steroidal saponin glycoside :-  dioscin and its aglycon is diosgenin. Small quantity of hecogenin. Resins :- Botagenin Alkaloids :- Dioscorine Sterol :- Cholesterol, Stigmasterol, p-sitosterol Enzyme :- Sapogenase Standards :-  Loss on drying :-  NMT 14% Total Ash value :- NMT 6% Acid Insoluble Ash:- NMT 0.5%

Uses :- 

Precursor of Vitamin D & Corticosteroid, In asthma (Dioscorea), Expectorant, Arthritis.


1. Which herb is use for production of steroids in industry ?

A. Liquorice

B. Brahmi

C. Digitalis

D. Dioscorea

2. Which of the following sentences is false about Dioscorea?

A. It is also known as yam.

B. It is belong to family Dioscoreace.

C. Dioscorea are used as anti hypertension agent.

D. Botagenin is present in Dioscorea.

3. Which of the following chemical constituents is not present in Dioscorea ?

A. Dioscorin

B. Sapogenase

C. Botagenin

D. Bita-sitosterol

4. Which steroidal heeb is used in asthma?

A. Digitalis

B. Senega

C. Yam

D. Ninjin

5. Which is true sentence about Dioscorea microscopic characteristics?

A. It has calcium oxalate Crystal.

B. It has paracytic stomata.

C. Absence of epidermis layer.

D. The major part of the drug is occupied by parenchyma cell.

6. Which of the following sterols are present in Dioscorea ?

A. Bita sitosterol

B. Ellagic acid

C. A and B

D. None of the above

7. Which of the following sentences is false about Dioscorea ?

A. Dioscorea is cultivated in North America.

B. Dioscorea Floribunda has 3-5% Diosgenin.

C. Dioscorea Floribunda has 6-7% Diosgenin.

D. Dioscorea composite has 4-5% Diosgenin.

8. Total Ash value of Dioscorea is

A. NMT 2

B. NMT 3

C. NMT 6

D. NMT 2

9. Match Of The Following

i Dioscorea Floribunda A. 6-7% Diosgenin

ii Dioscorea composite B. 4-5 %Diosgenin

iii Dioscorea Deltoid C.3-5%Diosgenin

A. i → B, ii→A, iii→ C

B. i → C, ii→ B, iii→ A

C. i →B, ii→A iii→ C

D.  i→ C, ii→ B iii→ A

10. Which herb is precursor of Vitamin D and corticosteroid ?

A. Glycrrhiza

B. Dioscorea Composite

C. Ninjin

D. Claviceps purpurea

Participate in Online FREE  GPAT  TEST: CLICK HERE

Participate in Online FREE  Pharmacist  TEST: CLICK HERE 

Participate in Online FREE  Drug Inspector  TEST: CLICK HERE 

Participate in CSIR NET JRF Mock Test

Participate GATE Mock Test

Answer Key :- 

1. D

2. C

3. D

4. C

5. C

6. D

7. C

8. C

9. B

10. B

Reference :-  16 edition of trease and evans Pharmacognosy ( pg.no. 311 and 312)

Dioscorea bulbifera L. (Dioscoreaceae): A review of its ethnobotany, pharmacology and conservation need


Leave a Reply

Your email address will not be published. Required fields are marked *

Free Video Lectures of Pharmacy Exams
Watch now
Admission open 2024 Clinical Research & Pharmacovigilance Courses
Apply now

Developed By Connect Globes