Germacrene Explained

Germacrenes are a class of volatile organic hydrocarbons, specifically, sesquiterpenes. Germacrenes are typically produced in a number of plant species for their antimicrobial and insecticidal properties, though they also play a role as insect pheromones. Two prominent molecules are germacrene A and germacrene D.

Structures

Germacrene has five isomers.

Natural occurrences

The essential oils of red deadnettle (Lamium purpureum)^[1] and hedgenettles (genus Stachys)^[2] are characterized by their high contents of germacrene D, as is Clausena anisata. It is also a major component of patchouli oil.

Further reading

General

• Adio . A. M. . Germacrenes A–E and related compounds: thermal, photochemical and acid induced transannular cyclizations . Tetrahedron . 2009 . 65 . 8 . 1533–1552 . 10.1016/j.tet.2008.11.050.

Germacrene A

• Deguerry . F. . Pastore . L. . Wu . S. . Clark . A. . Chappell . J. . Schalk . M. . The diverse sesquiterpene profile of patchouli, Pogostemon cablin, is correlated with a limited number of sesquiterpene synthases . Archives of Biochemistry and Biophysics . 2006-10-15 . 454 . 2 . 123–136. 10.1016/j.abb.2006.08.006 . 16970904 .
• Omura . H. . Honda . K. . Feeny . P. . From terpenoids to aliphatic acids: further evidence for late-instar switch in osmeterial defense as a characteristic trait of swallowtail butterflies in the tribe Papilionini . Journal of Chemical Ecology . 2006-09-01 . 32 . 9 . 1999–2012. 10.1007/s10886-006-9124-x . 16902823 . 25242966 .
• Forcat . S. . Allemann . R. K. . Stabilisation of transition states prior to and following eudesmane cation in aristolochene synthase . Organic and Biomolecular Chemistry . 2006-07-07 . 4 . 13 . 2563–2567. 10.1039/b604147g . 16791319 .
• Bertea . C. M. . Voster . A. . Verstappen . F. W. . Maffei . M. . Beekwilder . J. . Bouwmeester . H. J. . Isoprenoid biosynthesis in Artemisia annua: cloning and heterologous expression of a germacrene A synthase from a glandular trichome cDNA library . Archives of Biochemistry and Biophysics . 2006-04-15 . 448 . 1–2 . 3–12. 10.1016/j.abb.2006.02.026 . 16579958 .
• Lou . Y . Baldwin . I. T. . Silencing of a germin-like gene in Nicotiana attenuata improves performance of native herbivores . Plant Physiology . 2006-03-01 . 140 . 3 . 1126–1136. 10.1104/pp.105.073700 . 16461381 . 1400569 .
• Chang . Y.-J. . Jin . J. . Nam . H.-Y. . Kim . S.-U. . Point mutation of (+)-germacrene A synthase from Ixeris dentata . Biotechnology Letters . 2005-03-01 . 27 . 5 . 285–288. 10.1007/s10529-005-0681-9 . 15834787 . 21959582 .

Germacrene D

• Rivero Cruz . B. . Rivero Cruz . I . Rodríguez . J. M. . Cerda García-Rojas . C. M. . Mata . R. . Qualitative and quantitative analysis of the active components of the essential oil from Brickellia veronicaefolia by nuclear magnetic resonance spectroscopy . Journal of Natural Products . 2006-08-01 . 69 . 8 . 1172–1176. 10.1021/np060180b . 16933870 .
• Yang . F.-Q. . Li . S.-P. . Chen . Y. . Lao . S.-C. . Wang . Y.-T. . Dong . T.-T. . Tsim . K.-W. . Identification and quantitation of eleven sesquiterpenes in three species of Curcuma rhizomes by pressurized liquid extraction and gas chromatography-mass spectrometry . Journal of Pharmaceutical and Biomedical Analysis . 2005-09-15 . 39 . 3–4 . 552–558. 10.1016/j.jpba.2005.05.001 . 15946818 .
• Umlauf . D. . Zapp . J. . Becker . H. . Adam . K. P. . Biosynthesis of the irregular monoterpene artemisia ketone, the sesquiterpene germacrene D and other isoprenoids in Tanacetum vulgare L. (Asteraceae) . Phytochemistry . 2004-09-01 . 65 . 17 . 2463–2470. 10.1016/j.phytochem.2004.08.019 . 15381410 . 2004PChem..65.2463U .
• Agnihotri . V. K. . Thappa . R. K. . Meena . B. . Kapahi . B. K. . Saxena . R. K. . Qazi . G. N. . Agarwal . S. G. . Essential oil composition of aerial parts of Angelica glauca growing wild in North-West Himalaya (India) . Phytochemistry . 2004-08-01 . 65 . 16 . 2411–2413. 10.1016/j.phytochem.2004.07.004 . 15381015 . 2004PChem..65.2411A .
• Raal . A. . Paaver . U. . Arak . E. . Orav . A. . Content and composition of the essential oil of Thymus serpyllum L. growing wild in Estonia . Medicina (Kaunas) . 2004 . 40 . 8 . 795–800. 15300002 .
• He . X. . Cane . D. E. . Mechanism and stereochemistry of the germacradienol/germacrene D synthase of Streptomyces coelicolor A3(2) . Journal of the American Chemical Society . 2004-03-10 . 126 . 9 . 2678–2679. 10.1021/ja039929k . 14995166 .
• Arimura . G.-I. . Huber . D. P. W. . Bohlmann . J. . Forest tent caterpillars (Malacosoma disstria) induce local and systemic diurnal emissions of terpenoid volatiles in hybrid poplar (Populus trichocarpa × deltoides): cDNA cloning, functional characterization, and patterns of gene expression of (−)-germacrene D synthase, PtdTPS1 . The Plant Journal . 2004 . 37 . 4 . 603–616. 10.1111/j.1365-313X.2003.01987.x . 14756770 . free .

Notes and References

1. Flamini . G. . Cioni . P. L. . Morelli . I. . Composition of the essential oils and in vivo emission of volatiles of four Lamium species from Italy: L. purpureum, L. hybridum, L. bifidum and L. amplexicaule. Food Chemistry . 2005 . 91 . 1 . 63–68 . 10.1016/j.foodchem.2004.05.047 .
2. K. . Morteza‐Semnani . M. . Akbarzadeh . Sh. . Changizi . Essential oils composition of Stachys byzantina, S. inflata, S. lavandulifolia and S. laxa from Iran . Flavour and Fragrance Journal . 2005-11-01 . 21 . 2 . 300–303 . 10.1002/ffj.1594.