Unser 10. Leibniz Plant Biochemistry Symposium am 7. und 8. Mai war ein großer Erfolg. Thematisch ging es in diesem Jahr um neue Methoden und Forschungsansätze der Naturstoffchemie. Die exzellenten Vorträge über Wirkstoffe…
Omanische Heilpflanze im Fokus der Phytochemie IPB-Wissenschaftler und Partner aus Dhofar haben jüngst die omanische Heilpflanze Terminalia dhofarica unter die phytochemische Lupe genommen. Die Pflanze ist reich an…
Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
Ali, N. A. A.; Al-Fatimi, M. A.; Crouch, R. A.; Denkert, A.; Setzer, W. N.; Wessjohann, L.;Antimicrobial, Antioxidant, and Cytotoxic Activities of the Essential Oil of Tarchonanthus camphoratusNat. Prod. Commun.8683-686(2013)DOI: 10.1177/1934578X1300800534
The leaf essential oil of Tarchonanthuscamphoratus(Asteraceae) was obtained by hydrodistillation and analyzed by GC-MS. Fifty-six components were characterized, representing 94.2% of the total oil with oxygenated monoterpenes (48.3%) and oxygenated sesquiterpenes (32.7%) as the major groups. The principal constituents were identified as endo-fenchol (21.2%), trans-pinene hydrate (8.8%), caryophyllene oxide (7.5%), α-terpineol (6.4%), τ-cadinol (6.4%), and α-cadinol (5.2%). The essential oil was evaluated for its antimicrobial activity using a disc diffusion assay resulting in the moderate inhibition of a number of common human pathogenic bacteria, including methicillin-resistant Staphylococcus aureus(MRSA) and the yeast Candida albicans. The inhibition zones varied from 10 to 14mm/disc. Furthermore, the antioxidant capacity of the essential oil was examined using an in vitroradical scavenging activity test. The T. camphoratus essential oil scavenged 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), resulting in an IC50value of 5.6 mg/mL. At concentrations of 100 and 50μg/mL, the oil showed cytotoxic activity, with growth inhibition of 59.1% (±4.2), and 16.2% (±8.7) against HT29 tumor cells (human colonic adenocarcinoma cells), respectively(IC50 = 84.7 ± 7.5 μg/mL).
Publikation
Günnewich, N.; Page, J. E.; Köllner, T. G.; Degenhardt, J.; Kutchan, T. M.;Functional Expression and Characterization of Trichome-Specific (-)-Limonene Synthase and (+)-α-Pinene Synthase from Cannabis sativaNat. Prod. Commun.(2007)DOI: 10.1177/1934578X0700200301
Two recombinant, stereospecific monoterpene synthases, a (-)-limonene synthase (CsTPS1) and a (+)-α-pinene synthase (CsTPS2), encoded by Cannabis sativa L. cv. ‘Skunk’ trichome mRNA, have been isolated and characterized. Recombinant CsTPS1 showed a Km value of 6.8 μM, a Vmax of 1.1 × 10−4 μmol/min and Vmax/Km of 0.016; the pH optimum was determined at pH 6.5, and a temperature optimum at 40°C. Recombinant CsTPS2 showed a Km value of 10.5 μM, a Vmax of 2.2 × 10−4 μmol/min and Vmax/Km of 0.021; the pH optimum was determined at pH 7.0, and a temperature optimum at 30°C. Phylogenetic analysis showed that both CsTPSs group within the angiosperms and belong to the Tpsb subgroup of monoterpene synthases. The enzymatic products (-)-limonene and (+)-α-pinene were detected as natural products in C. sativa trichomes.