Page 39 - phytochemistry I - PharmD Clinical

- Depending on the plant family volatile oils may occur in specialized
secretory structures:
- Petals of flowers (Rose)
- Barks and leaves (Cinnamon)
- Pericarp of fruits (Umbelliferous fruits)
- Stems and leaves glandular hair (Mentha)
- Petals and rind of fruits and leaves (Orange)

Combination of Volatile Oils in the plants:
 Volatile oils may combine with a sugar part to form a glycoside.
 Volatile oils may combine with:

Gums ……. Oleo-gums
Resins ……. Oleo-resins
Both ……. Oleo-gum resins

Why do plants synthesize V.O.?
Physiological significance:
Some scientists think that volatile oils are waste products, not formed to
serve any biological function.
Several ecological theories state that plants synthesize V.O. to use them
for:

• Attraction of insects.
• Defense agents.
• Solvents for wound-healing resins and gums.
• A way of eliminating certain abnormal metabolic products

(Detoxification products).

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