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--- ageratum_conyzoides_l [2015/03/14 11:26] – andreas
+++ ageratum_conyzoides_l [2015/06/13 09:36] (aktuell) – Externe Bearbeitung 127.0.0.1
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 Annual herb, up to 1m high, native to tropics,subtropics (America, Africa, Asia); stem pubescent; leaves opposite, crenate; flowers blue to lilac, 4-8mm across.
-"The essential oils isolated from the leaves of Ageratum houstonianum Mill, and Ageratum conyzoides L. by hydrodistillation were analysed by GLC and GC-MS. The essential oil of A. houstonianum contained 7-methoxy-2,2-dimethylchromene (precocene I) and ageratochromene (precocene II) in almost similar amounts (32% and 24% respectively) whereas that of A. conyzoides was rich in precocene I (81%) and poor in precocene II (0.2%)." \\
+"As a medicinal plant, Ageratum conyzoides has limited uses due to its toxicity. It is also an insecticide and nematicide. Ingesting A. conyzoides can cause liver lesions and tumors. There was a mass poisoning incident in Ethiopia as a result of contamination of grain with A. conyzoides. The plant contains the pyrrolizidine alkaloids lycopsamine and echinatine." \\
+[[https://en.wikipedia.org/wiki/Ageratum_conyzoides]] \\
+[Plants containing pyrrolizidine alkaloids: toxicity and problems, H. Wiedenfeld, Food Additives & Contaminants: Part A, Vol. 28(3), 2011, 282-292]
+{{:lycopsamine.jpg|}} lycopsamine
+"The essential oils isolated from the leaves of [[http://en.wikipedia.org/wiki/Ageratum_houstonianum|Ageratum houstonianum]] Mill, and Ageratum conyzoides L. by hydrodistillation were analysed by GLC and GC-MS. The essential oil of A. houstonianum contained 7-methoxy-2,2-dimethylchromene (precocene I) and ageratochromene (precocene II) in almost similar amounts (32% and 24% respectively) whereas that of A. conyzoides was rich in precocene I (81%) and poor in precocene II (0.2%)." \\
 [Aromatic plants of tropical central Africa. Part X Chemical composition of the essential oils of Ageratum houstonianum Mill. and Ageratum conyzoides L. from Cameroon., Menut, C., Lamaty, G., Zollo, P.H., Kuiate, J.R., Bessiere, J.M., Flavour and fragrance journal, Vol.8(1), 1993, 1-4]
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 "Inhibitory effects of essential oil of Ageratum conyzoides, on the mycelial growth and aflatoxin B1 production by Aspergillus flavus were studied. Cultures were incubated in yeast extract-sucrose (YES) broth for days at 25 °C at the following different concentrations of the essential oil (from 0.0 to 30 μg/mL). The essential oil inhibited fungal growth to different extents depending on the concentration, and completely inhibited aflatoxin production at concentrations above 0.10 µg/mL. The analysis of the oil by GC/MS showed that its main components are precocene II (46.35%), precocene I (42.78%), cumarine (5.01%) and trans-caryophyllene (3.02%). Comparison by transmission electron microscopy of the fungal cells, control and those incubated with different concentrations of essential oil, showed ultra-structural changes which were concentration dependent of the essential oil of A. conyzoides. Such ultra-structural changes were more evident in the endomembrane system, affecting mainly the mitochondria. Degradation was also observed in both surrounding fibrils." \\
 [Ageratum conyzoides essential oil as aflatoxin suppressor of Aspergillus flavus., Nogueira, J.H., Gonçalez, E., Galleti, S.R., Facanali, R., Marques, M.O., Felício, J.D., International journal of food microbiology, Vol.137(1), 2010, 55-60]
+"Aqueous extracts of Ageratum conyzoides L. harvested in Brazil (commercial, flowering and non-flowering samples) were prepared according to the prescribed method and analyzed by HPLC-HRMS. The pyrrolizidine alkaloids lycopsamine, dihydrolycopsamine, and acetyl-lycopsamine and their N-oxides, were detected in the analyzed extracts, lycopsamine and its N-oxide being known hepatotoxins and tumorigens. Together with the pyrrolizidine alkaloids identified by HPLC-HRMS, thirteen phenolic compounds were identified, notably, methoxylated flavonoids and chromenes. Toxicological studies on A. conyzoides are necessary, as is monitoring of its clinical use. To date, there are no established safety guidelines on pyrrolizidine alkaloids-containing plants, and their use in Brazil." \\
+[Pyrrolizidine alkaloids in medicinal tea of Ageratum conyzoides, Bosi C.F. et al., Revista Brasileira de Farmacognosia, Vol.23(3), 2013, 425–432]
 "The chemical composition of the hydro-distilled essential oils of leaf, flower, stem and root of Ageratum conyzoides L. were analyzed by gas chromatography... The major constituents were 6-demethoxy-ageratochromene (precocene I) and β-caryophyllene dominated in leaf (72.3%; 12.1%), stem (66.5%; 10.2%), flower (50.3%; 14.6%) and root (79.3%; 6.0%) essential oils. The compound ageratochromene (precocene II) was found relatively high amount in flower (10.5%) than leaf (3.1%), root (0.4%) and stem (0.3%) oils. The occurrence of androencecalinol is being reported for the first time in leaf, flower, stem and root oils in low quantity (0.7 - 0.3%)." \\