Comprising of C and H only: They essentially consist of hydrocarbon present in the natural products.

4.1.4.1 Comprising of C and H only: They essentially consist of hydrocarbon present in the natural products.

Examples:

(a)            β-Myrcene: It is an unsaturated acyclic hydrocarbon found in oil of bay, verbena, hop and others.

(b)            Ocimene: It is also an unsaturated acyclic hydrocarbon found in the essential oil distilled from the fresh leaves of Ocimum basilicum L. and from the fruits of Evodia rutaecarpa (Juss.) Hook & Thoms. It exists in two modifications and forms. The cis- and trans-refers to the stereochemistry at the double-bond between C-3 and C-4.

(c) p-Cymene (Dolcymene): It is an aromatic hydrocarbon and occurs in a number of essential oils e.g., sage, lemon, thyme, nutmeg, coriander, origanum, cinnamon.

(d) Limonene (Syn: Cinene, Cajeputene, Kautschin): It is an alicyclic hydrocarbon and further classified into monocyclic terpene. It occurs in various ethereal oils particularly in oils of lemon, orange, caraway, dill and bergamot.

(e) α-Pinene: It is also an alicyclic hydrocarbon and further classified into bicyclic monoterpene d-α-pinene obtained from Port Oxford Cedar Wood Oil (Chamaecyparls lawsorliana Parl.). l- α-Pinene obtained from Mandarin Peel Oil (Citrus reticulata Blando).

REFERENCES

Ashutosh Kar (2003), Pharmacognosy and Pharmaco biotechnology, 2nd Edition

‘Handbook of Medicinal Herbs’ (2001), J.A. Duke, CRC-Press, London, 1st Edn.

William Charles Evans (2002), Trease and Evans Pharmacognosy 15th Edition by: Trease, Bailliere Tindall; Evans.

Ramstad (1956), E., ‘Modern Pharmacognosy’, McGraw Hill, London.