Antifeedant C20 diterpene alkaloids.
ABSTRACT We have tested the insect antifeedant and toxic activity of 21 C20 diterpenoid alkaloids on Spodoptera littoralis and Leptinotarsa decemlineata. The antifeedant effects of the test compounds were structure- and species-dependent. The most active antifeedants to L. decemlineata and S. littoralis were the rearranged form of hetisine (20; EC50 = 1.7 microg/cm2) and 19-oxodihydroatisine (9; EC50 = 0.1 microg/cm2), resp. Glandulosine (8) moderately affected orally injected S. littoralis larvae. A few compounds (13-oxocardiopetamine (4), 9, and atisinium chloride (13)) had cytotoxic effects to insect-derived Sf9 cells with varying degrees of selectivity with respect to mammalian CHO cells. Compounds 4 and 15,22-O-diacetyl-19-oxodihydroatisine (10) increased Trypanosoma cruzi mortality. Our results support the plant protective role of C20 diterpenoid alkaloids and open a new field for parasite control strategies.
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ABSTRACT: In the present study, 30 pure monoterpenes were tested for their toxicity against first, second and third instars larvae and adults of Colorado potato beetle (Leptinotarsa decemlineata Say). The majority of tested compounds were found to be toxic to the larvae and the adults, however variable degree of toxicity with a range of 20–100% mortality. In general, monoterpene hydrocarbons exhibited high toxicity as compared with oxygenated monoterpenes. Among the tested monoterpene hydrocarbons, β-pinene, γ-terpinene, 3-carene as well as myrcene showed strong toxicity against all instars larvae. On the other hand, 1,8-cineole, fenchone, linalool and terpinen-4-ol were more toxic against the larvae as compared with the toxicities of other oxygenated monoterpenes. Borneol, fenchol, geranyl acetate, menthol, nerol acetate and α-terpineol showed weak toxicity against the larvae, whereas no significant toxicity was observed for isomenthol against the larvae. Some tested compounds showed different toxicities against both adults and larvae. For instance, menthone was more toxic against the adults than the larvae. Likewise, monoterpene hydrocarbons showed the higher toxicity against the adults than oxygenated monoterpenes. Limonene, α-pinene and β-pinene caused 100% mortality against the adults at two doses after 24h of exposure. Among the tested oxygenated monoterpenes, 1,8-cineole, fenchone and menthone were much more effective against the adults. The present results indicated that 1,8-cineole, fenchone, β-pinene and γ-terpinene can be used as potential control agents against both the larvae and adults of Colorado potato beetle.Industrial Crops and Products - IND CROPS PRODUCTS. 01/2007; 26(3):278-297.
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ABSTRACT: The plant Aconitum orochryseum Stapf. (Ranunculaceae) is employed together with other plants in Bhutanese traditional medicine and is indicated for malaria-associated fever. To study the in vitro antiplasmodial activity of atisinium chloride, the major alkaloid from Aconitum orochryseum. Atisinium chloride was extracted and purified from aerial parts of Aconitum orochryseum and its structure and absolute configuration confirmed by single crystal X-ray crystallography. The crude methanol extract, crude alkaloid fraction, and atisinium chloride were tested for in vitro antiplasmodial activity against the malarial Plasmodium falciparum strains TM4/8.2 (TM4; wild type) and K1CB1 (K1; chloroquine and antifolate resistant). The diterpenoid alkaloid atisinium chloride was shown to have moderate antiplasmodial activities with IC(50) values of 4 microM and 3.6 microM, respectively against the TM4 strain and the K1 strain of Plasmodium falciparum. Our studies provide the first evidence in support of one of the indicated treatments with Aconitum orochryseum in Bhutanese traditional medicine. This alkaloid also represents a potential new antimalarial structural lead.Journal of ethnopharmacology 08/2010; 130(3):559-62. · 2.32 Impact Factor
- Solid-State Circuits Conference, 1991. Digest of Technical Papers. 38th ISSCC., 1991 IEEE International; 03/1991