Diosgenin is a steroidal sapogenin that can be isolated from dried tubers of several Dioscorea species. It is the aglycone produced during hydrolysis of saponins in the plants. Diosgenin has a (3β,25R)-spirost-5-en-3-ol structure. It can be isolated from a powdered and ethanol extracted plant material via acid hydrolysis, which yields about 85% crude diosgenin. The precipitate is then purified by filtration, washing, and recrystallization to obtain diosgenin. Diosgenin is a precursor to various steroidal drugs due to its ability to be oxidized to attach an

1. DIOSGENIN

2. INTRODUCTION
• Synonyms : Yam
• Biological source: It consists of dried tubers of Dioscorea deltiodea,
Dioscorea floribunda, Dioscorea composita and Dioscorea prazeri or
a combination of first two belonging to the family Dioscoreaceae.
• Chemical constituents:
steroidsl saponin glycoside – Dioscin
Dioscin on hydrolysis gives diosgenin and two molecules of
rhamnose
Other saponin glycoside – Smilagenin,Epismilagenin, Yamogenin
Also contains an enzyme called sapogenase.

3. CHEMISTRY
• Structure
. ( 3β ,25 R)–spirost–5–en–3–ol

4. • It is a steroid sapogenin product of hydrolysis by strong bases, acids,or
enzymes of saponins.
• Hydrolysis of the saponins causes scission of trisaccharide at 3- position
and formation of aglycone, diosgenin.
• Oxidation by chromium trioxide causes preferential attack at the electron
rich enol ether double bond.
• This transformation converts the side chain at C-17 in diosgenin to acetyl
group required for many steroid drugs.

5. ISOLATION
ALCOHOLIC EXTRACTION METHOD
Diosgenin tubers are cut into small pieces and dried under sun
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The dried tubers are powdered, extracted with ethanol or methanol twice for 6-8 hrs.
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It is then filtered and the filtrate is concentrated to a syrupy liquid.
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The concentrated liquid is hydrolysed using an acid, hydrochloric acid or sulphuric acid for 2-
12 hrs.
↓

6. ISOLATION
About 85% of crude diosgenin is precipitated.
↓
Precipitates are filtered , washed ,with water and purified with alcohol.

7. REFERENCE
1. Textbook of Pharmacognosy and phytochemistry ,2nd edition, Biren
Shah, A.K Seth
2. Textbook of pharmacognosy and phytochemistry Sapna Malviya, Swati
Rawat, Neelesh Malviya pg no:51