This document discusses methods for isolating and separating terpenoids. It describes both chemical and physical methods. The chemical methods involve using reagents like Tilden's reagent or phthalic anhydride to form crystalline adducts or diesters of terpenoids which can then be separated. Physical methods include fractional distillation under reduced pressure to separate terpenoids based on their boiling points, and various chromatography techniques like adsorption chromatography to separate terpenoids based on their differential adsorption on adsorbents like alumina and silica gel.

1. Isolation and separation of
Terpenoids
Prepared by
Dr. N.GOPINATHAN
ASSISTANT PROFESSOR
DEPARTMENT OF PHARMACEUTICAL CHEMISTRY
FACULTY OF PHARMACY
SRI RAMACHANDRA UNIVERSITY
CHENNAI-116
TAMILNADU
INDIA

2. • Essential oil contain a number
of terpenoids belonging to
mono and sesquiterpenoid
group.
• Isolation of individual
terpenoid can be achieved by
chemical as well as physical
method

3. Chemical method

4. • Certain chemical methods have been applied
for the separation of terpenoids.
• In 1877, tilden discovered that whenever
terpenoid hydrocarbon are treated with
nitrosyl chloride in chloroform [ Tilden’s
reagent].
• Crystalline adducts having sharp melting
point are obtained
• The adducts were separated and
decomposed into their corresponding
hydrocarbons.

5. Terpenoid- alcohol
• It is separated by their reaction with
Phthalic anhydride to form diesters
when the primary alcohol react
readily, secondary alcohol less
readily and tertiary do not react.
• The diesters are extracted with
NaHCO3 and then decomposed by
alkali to the parent terpenoid
alcohol

7. • Terpenoid aldehydes and
ketones were seperated by
reaction with common
carbonyl reagent such
asNaHCO3, 2,4 dinitro penyl
hydrazine, phenyl hydrazine
reagent.

8. Physical method
• Fractional distillation method
• The various terpenoids present in essential
oil are separated by fractional distillation
method.
• The terpenoid hydrocarbon distill over first
followed by oxygenated derivative.
• Distillation of the residue under reduced
pressure yield sesquiterpenoids and these
are separated by fractional distillation.

9. • Fractional distillation is to be
carried out under reduced
pressure in the presence of an
inert gas.
• These conditions are essential
because many terpenes are
sensitive to heat and
atmospheric oxygen.

10. Chromatography
• In adsorption chromatography, the
essential oil is made to flow through
a particular adsorbent
• Different types of terpenoid are
adsorbed at different places on the
adsorbent to form different
chromatogram

11. • Then various chromatograms are
eluted by different solvent
system to get different elute.
• Alumina and silica gel are used
as adsorbent.
• Vapor phase partition , counter
current and gas chromatography
have been used.

12. Thank you