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Abstract The potency of Piper nigrum seed and leaf, Aframomum meleguata seed and Ageratum conyzoides leaf extracts in the control of cassava tuber rot caused by Rhizopus oryzae was investigated. Water, ethanol and petroleum ether were used as extracting solvents. These extracts were fungitoxic both in vitro and in vivo against the test pathogen. P. nigrum seed extracts were the best followed by those of A. meleguata seed, A. conyzoides leaf and then P. nigrum leaf. The extracts were more effective in controlling rot development in unwounded than wounded tubers especially when they were applied before inoculation with the test pathogen. Ethanol extracts gave the highest growth inhibition in vivo followed by water and the petroleum ether extract whereas water extracts showed marked superiority over the extracting solvents in checking rot development in cassava tuber. Water and ethanol extracts of P. nigrum seed and leaf, A. meleguata seed and A. conyzoides leaf could be used as pesticide of plant origin in the control of R. oryzae causing cassava tuber rot in storage. 相似文献
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Kenmogne M Prost E Harakat D Jacquier MJ Frédérich M Sondengam LB Zèches M Waffo-Téguo P 《Phytochemistry》2006,67(5):433-438
Five labdane diterpenoids, (3-5), zambesiacolactone A (7) and zambesiacolactone B (8), were isolated from the seeds of Aframomum zambesiacum (Baker) K. Schum., along with five known labdanes and a linear sesquiterpene, nerolidol. Their structures were elucidated by spectroscopic analysis. Their antiplasmodial activity was evaluated in vitro against Plasmodium falciparum. Compound 3 was the most active with an IC(50) value of 4.97 microM. 相似文献
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The essential oil from the rhizomes of Aframomum sceptrum (Zingiberaceae) was analyzed by GC/MS, and its major constituents were found to be β‐pinene (12.7%), caryophyllene oxide (10.0%), and cyperene (6.0%). The oil was also evaluated for antimicrobial activities, in comparison with β‐pinene, caryophyllene oxide, and the leaf essential oil of Melaleuca alternifolia (Myrtaceae). The A. sceptrum essential oil exhibited bacteriostatic activity against the Gram‐positive bacteria Bacillus subtilis, Staphylococcus epidermidis, and S. aureus, but not against Gram‐negative bacteria. Moreover, it showed mild fungicidal activity against Candida albicans and Aspergillus fumigates, and remarkable antiprotozoal activity against Trypanosoma brucei brucei (MLC of 1.51 μl/ml) and Trichomonas vaginalis (IC50 of 0.12±0.02 and MLC of 1.72 μl/ml). 相似文献
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Tomla C Kamnaing P Ayimele GA Tanifum EA Tsopmo A Tane P Ayafor JF Connolly JD 《Phytochemistry》2002,60(2):197-200
Three labdane diterpenoids, 8beta,17-epoxy-3beta,7beta-dihydroxy-12(E)-labden-16,15-olide (1), methyl 8beta,17-epoxy-3beta,7beta,15-trihydroxy-12(E)-labden-16-oate (2) and 3beta,7beta,8beta,12zeta,17-pentahydroxylabdan-16,15-olide (3) have been isolated from the seeds of Afromomum sceptrum K. Schum (Zingiberaceae) and their structures assigned on the basis of their spectroscopic properties. Nerolidol, and the known flavonoids 3-acetoxy-4',5,7-trihydroxyflavanone, and 3,4',5,7-tetrahydroxyflavanone were also obtained. 相似文献
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Donald A. Ukeh Michael A. Birkett John A. Pickett A. Jennifer Mordue 《Phytochemistry》2009,70(6):751-288
The repellent activity of alligator pepper, Aframomum melegueta, and ginger, Zingiber officinale (Zingiberaceae), against the maize weevil, Sitophilus zeamais (Coleoptera: Curculionidae), was investigated in four-way olfactometer bioassays. Results showed that vacuum distilled A. melegueta and Z. officinale extracts were repellent towards adult S. zeamais both in the absence and the presence of maize, Zea mays, grains. Bioassay-guided liquid chromatographic fractionation of the distillates showed that fractions containing oxygenated compounds accounted for the repellent activity. Coupled gas chromatography-mass spectrometry (GC-MS), followed by GC peak enhancement and enantioselective GC using authentic compounds, identified 3 major compounds in the behaviourally active fractions of A. melegueta and Z. officinale to be (S)-2-heptanol, (S)-2-heptyl acetate and (R)-linalool in a ratio of 1:6:3, and 1,8-cineole, neral and geranial in a ratio of 5.48:1:2.13, respectively. The identification of these behaviourally active compounds provides the scientific basis for the observed repellent properties of A. melegueta and Z. officinale, and demonstrates the potential for their use in stored-product protection at the small-scale farmer level in Africa. 相似文献
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Abstract Investigations were carried out on the pesticidal potentials of seed of Piper nigrum and Aframomum melegueta and leaves of P. nigrum and Ageratum conyzoides using water, ethanol and petroleum ether as extracting solvents. Leaf extracts of P. nigrum and A. conyzoides and seed extracts of A. melegueta and P. nigrum significantly inhibited the mycelial radial growth and mycelial biomass of Botryodiplodia acerina in vitro. Ethanol extracts recorded the highest growth inhibition followed by water and petroleum ether extracts. The extracts checked the rot development in unwounded cassava tubers especially when they were applied before spray-inoculating with B. acerina. Water leaf extracts of P. nigrum and A. conyzoides and seed extracts of A. melegueta and P. nigrum could be a potent source of natural pesticide for managing post-harvest rot of cassava tubers caused by B. acerina. 相似文献
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Zakaria Cheikh-Ali Timothée Okpekon François Roblot Christian Bories Matthieu Cardao Jean-Christophe Jullian Erwan Poupon Pierre Champy 《Phytochemistry letters》2011,4(3):240-244
Two novel labdane diterpenoids, 15ξ-methoxy-labdan-8(17),11(E),13(14)-trien-15,16-olide (1) and 12(S)-hydroxy-15ξ-methoxy-labdan-8(17),13(14)-dien-15,16-olide (2) were isolated from the rhizomes of Aframomum sceptrum K. Schum (Zingiberaceae). Their structures were established on the basis of their spectroscopic data. Stigmast-4-en-6β-ol-3-one and caryophylene oxide were also obtained. In vitro trypanocidal and leishmanicidal activities of labdanes 1 and 2 were evaluated. Compound 2 exhibited activity similar to that of reference drugs against Leishmania donovani. 相似文献
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Adenike Christy Adeyemo Michael Olufemi Ashamo Olusola Olasumbo Odeyemi 《Archives Of Phytopathology And Plant Protection》2013,46(15):1841-1851
This study was conducted to investigate the potential of Aframomum melegueta leaf and seed as biopesticide against Sitotroga cerealella infestation on two paddy varieties at ambient temperature of 28 °C ± 2 °C and relative humidity of 75?±?5%. The two paddy varieties used were FARO 44 and FARO 52. Leaf and seed powders of A. melegueta were made at 0.1, 0.2, 0.4, 0.6 and 0.8 g while the extracts were made at 1, 2, 3, 4 and 5%. Mortality of the insect on the two paddy varieties was record after 24, 48 and 72?h of application of the powders and extracts of this plant. The highest number of the insect was observed on FARO 52 treated with seed powders and extracts of A. melegueta. Only the seed extracts were able to achieve 100% moth mortality within 72 h of application at 4% concentration and were significantly (p?<?0.05) different from others. The powders and extracts of the plant significantly reduced or prevented the adult emergence of the insect and increased their developmental period as well reduced or prevented seed weight loss with seed powders and extracts having the greatest effect on the paddy variety FARO 44. The antinutritional components present in the two paddy varieties include phytate, oxalate, total phenol and tannin cyanide, and the amylase content was also determined, with FARO 44 having the highest value of 17.31, 0.18, 0.43, 10.46 and 5.49 for phytate, oxalate, tannin, cyanide and amylase content, respectively. Powders and extracts of A. melegueta could be introduced into pest management techniques since they are effective against S. cerealella. 相似文献
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