Larrea

One consequence of the shift from grassland to shrubland is the potential for significant increases in volatile hydrocarbons added to the atmosphere. The leaves of creosotebush, Larrea tridentata, yielded 0.1 to 0.2 percent of a complex mixture of volatile compounds. That mixture contains several hundred compounds of which 100 accounted for more than 90% of the total volatiles (23). The volatiles that were identified included four monoterpene hydrocarbons, four oxygenated monoterpenes, six sesquiterpene hydrocarbons, eight aromatics like benzyl acetate and ethyl benzoate, plus... 

Seigler. In Editors Mabry, T.J., J.H. Hunziker and D.R. DiFeo, Jr. Creosotebush Biology and Chemistry of Larrea in New World Deserts. Dowden, Hutchinson and Ross, Inc. Stroudsburg, PA 1977. pp.115-134. 

Fig. 2.70 Map of transects from Encelia farinosa study where circle size represents concentration differences and transects from Larrea tridentata study. Map of transects from Encelia farinosa study where eastern (E) and western (W) types are identified...

Fig. 2.71 Compound 229 from Larrea tridentata. Compounds 230-233, flavonoids from Chryso-splenium glechomaefolium. Compounds 234-236, flavonoids from Quercus rubrsi...

Table 7.1 Flavonoid aglycones from leaf surfaces of Larrea tridentata and L. divaricata (from Mabry et al., 1977)...

Downum, K. R., Dole, J. and Rodriguez, E. 1988. Nordihyroguaiaretic acid inter- and intrapop-ulational variation in the Sonoran Desert creosote bush (Larrea tridentata, Zygophyllaceae). Biochem. Syst. Ecol. 16 551-555... 

Herbal remedies that have been reported to be he-patotoxic include chaparral (Larrea tridentata), germander (Teucrium chamaedrys), and life root (Senecio aureus) [18]. Cases reported patients developing jaundice, fatigue, pruritus, markedly elevated serum liver enzyme levels, severe cholestasis, hepatitis, and hepatocellular injury or necrosis documented by serial liver biopsies [19-21]. Signs and symptoms may occur as early as 3 weeks to as late as 7 months following ingestion [20,21]. 

Hidalgo OH, Lopez MJ, Carazo EA, Larrea MSA, Reuvres TBA. 2003. Determination of dexamethasone in urine by gas chromatography with negative chemical ionization. J Chromatogr B 788 137. 

Plant parts often differ in their levels of secondary metabolites (Table 11.4), some containing extremely high levels. For example, the creosote bush, Larrea tridentata, of the western United States has phenolic resins concentrated in leaves, amounting to as much as 18% of dry weight. In experiments, desert woodrats, Neotoma lepida, selected plant parts of creosote bush with low levels of resins (Meyer and Karazov 1989). 

Meyer, M. W. and Karasov, W. H. (1989). Antiherbivore chemistry of Larrea tridentata effects on woodrat Neotoma lepida) feeding and nutrition. Ecology 70,953-961. 

Some typical genera Balanites Guaiacum Fagonia Kallstroemia Larrea Porlieria Tribulus Zygophyllum... 

Larrea tridentata occurs throughout the Mojave, Sonoran, and Chihuahuan Deserts. Its distribution extends from southern California northeast through southern Nevada to the southwest corner of Utah and southeast through southern Arizona and New Mexico to western Texas and north-central Mexico. It is known to attain ages of several thou-... 

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