Quantitative co-occurrence of sesquiterpenes; a tool for elucidating their biosynthesis in Indian sandalwood, Santalum album

• Published in: Phytochemistry (Oxford) Vol. 67; no. 22; pp. 2463 - 2468
• Main Authors: Jones, Christopher G., Ghisalberti, Emilio L., Plummer, Julie A., Barbour, Elizabeth L.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01-11-2006; Elsevier
• Subjects: Alcohols - chemistry; bergamotenes; Biological and medical sciences; biosynthesis; bisabolol; chemical constituents of plants; Chemical constitution; chemotaxonomy; curcumene; epi-β-Santalene; Essential oil; essential oils; Fundamental and applied biological sciences. Psychology; Heartwood; India; Metabolism; Metabolism. Physicochemical requirements; Molecular Structure; parasitic plants; Phosphates - chemistry; Phosphates - metabolism; Plant physiology and development; plant taxonomy; qualitative analysis; quantitative analysis; santalenes; Santalols; Santalum - chemistry; Santalum - metabolism; Santalum album; Sesquiterpenes - chemistry; Sesquiterpenes - metabolism; sesquiterpenoids; α- trans-Bergamotene; α-Santalene; β-Santalene; Western Australia; India; β-Santalene; epi-β-Santalene; α- trans-Bergamotene; Heartwood; Essential oil; α-Santalene; Santalols; Santalum album; Enzyme; Sesquiterpenes; Biosynthesis; Yield; α-trans-Bergamotene
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/j.phytochem.2006.09.013

Striking quantitative co-occurrence patterns exist between the sesquiterpenes of Indian sandalwood (
Santalum album) oil. The biosynthesis of α- and β-santalene being derived from a common carbocation intermediate is evidenced by the strong linear correlation between these two compounds.
A chemotaxonomic approach was used to investigate biosynthetic relationships between heartwood sesquiterpenes in Indian sandalwood,
Santalum album L. Strong, linear relationships exist between four structural classes of sesquiterpenes; α- and β-santalenes and bergamotene; γ- and β-curcumene; β-bisabolene and α-bisabolol and four unidentified sesquiterpenes. All samples within the heartwood yielded the same co-occurrence patterns, however wood from young trees tended to be more variable. It is proposed that the biosynthesis of each structural class of sesquiterpene in sandalwood oil is linked through common carbocation intermediates. Lack of co-occurrence between each structural class suggests that four separate cyclase enzymes may be operative. The biosynthesis of sandalwood oil sesquiterpenes is discussed with respect to these co-occurrence patterns. Extractable oil yield was correlated to heartwood content of each wood core and the oil composition did not vary significantly throughout the tree.