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1.
In the surroundings of greenhouses specimens, ofF. occidentalis have been found in the flowers of 23 out of 34 cultivated and weed plants. Some of these plant species are hosts of the tomato spotted wilt virus (TSWV).F. occidentalis can survive in the field during one part of the vegetation period. The question of overwintering in the field must yet be cleared up.  相似文献   

2.
Kumar R  Saha A  Saha D 《Fitoterapia》2012,83(1):230-233
A new γ-lactone coumarin, named as excavarin-A, showing antifungal activity was isolated from the leaves of Clausena excavata by bioassay guided fractionation method. The structure was elucidated by spectroscopic data analysis and identified as 7((2E)-4(4,5-dihydro-3-methylene-2-oxo-5-furanyl)-3-methylbut-2-enyloxy) coumarin. Minimum inhibitory concentration (MIC) was determined against fifteen fungal strains pathogenic against plants and human. The least MIC was recorded against the human pathogen, Candida tropicalis and the plant pathogens Rhizoctonia solani and Sclerotinia sclerotiorum. Antifungal activities against the human pathogens, Aspergillus fumigatus and Mucor circinelloides and plant pathogens, Colletotrichum gloeosporioides, Lasiodiplodia theobromae, Fusarium oxysporum and Rhizopus stolonifer were stronger than that of the standard antimicrobials.  相似文献   

3.
Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen which causes severe morbidity and mortality worldwide. Seventeen Thai medicinal plants were investigated for their activity against MRSA. Garcinia mangostana was identified as the most potent plant, and its activity was traced to the prenylated xanthone, α-mangostin (MIC and MBC values of 1.95 and 3.91 µg/ml, respectively).  相似文献   

4.
Ethanolic extract from the fruits of Pimpinella anisoides, an aromatic plant and a spice, exhibited activity against AChE and BChE, with IC50 values of 227.5 and 362.1 μg/ml, respectively. The most abundant constituents of the extract were trans-anethole, (+)-limonene and (+)-sabinene. trans-Anethole exhibited the highest activity against AChE and BChE with IC50 values of 134.7 and 209.6 μg/ml, respectively. The bicyclic monoterpene (+)-sabinene exhibited a promising activity against AChE (IC50 of 176.5 μg/ml) and BChE (IC50 of 218.6 μg/ml).  相似文献   

5.
The influence of variable photoperiods on the feeding activity and fecundity of Galendromus occidentalis (Nesbitt) was studied on a diet of Tetranychus urticae Koch eggs. Starved G. occidentalis females were fed T. urticae eggs under ten 24-h light:dark regimes. Half of the tests started during photophase and the other half during scotophase. T. urticae eggs that were consumed and G. occidentalis eggs that were laid were counted at the end of each photophase and scotophase in a 24 h period. In general, G. occidentalis consumed more T. urticae eggs per h in the first phase of the experiment than in the second, regardless of whether the lights were on or off. In contrast to egg consumption, there were no statistical differences in the mean daily fecundity at the end of the 24-h periods. However, when the experiment was started during photophase, higher fecundity/h was encountered during scotophase than during the photophase. As a result, egg consumption rates were affected by photoperiods in both phases of the experiments. Logistic regression analysis revealed that variable photoperiods and egg consumption did not influence the fecundity of G. occidentalis.  相似文献   

6.
Aster flaccidus bge has been used as traditional medicine in northwestern China. Two new phenylpropanoids (12) including one lignan: (7′R, 8S)-9′-lariciresinol-(α-methyl)-butanoate (1), 5,9-dimethoxyl-7-(α-methyl)-butanoxyl-phenyl-2E-propenol-(α-methyl)-butanoate (2) isolated from the chloroform extract of the root of Aster flaccidus bge were identified by means of extensive spectroscopic studies: 1D and 2D NMR spectra as well as HRMS analysis. They have not obvious anti-HIV-1 therapeutic activity (TI = 1.0–1.1) compared with AZT (TI = 55,556) as the result of the determination of their in vitro anti-HIV-1 activity while compound 2 displays strong antitumor activity against BEL 7402 (human liver carcinoma) with cisplatin as a positive control and the effect increases with the measuring-time going on (24 h, IC50: 106.67 ± 8.47 µM — 72 h, IC50: 50.51 ± 6.11 µM).  相似文献   

7.
A radical scavenging guided phytochemical study on the stem bark of Tecoma mollis afforded seven active phenylpropanoid glycosides (17), including a new one (4), and one iridoid (8). The structures of the isolated compounds were elucidated on the basis of spectroscopic evidences and correlated with known compounds. Compounds (17) displayed promising antioxidant activity (DPPH assay) in relation to ascorbic acid (positive control). The antimicrobial activity for compounds (18) was evaluated against five bacterial and five fungal strains. The isolated compounds exhibited nonselective weak to moderate antimicrobial activity. The highest antileishmanial activity against Leishmania donovani was observed for compound (7) with an IC50 value of 6.71 μg/ml, using pentamidine and amphotericin B as drug controls. Compound (5) exhibited moderate antimalarial activity (45% inhibition) against chloroquine sensitive (D6) clones of Plasmodium falciparum.  相似文献   

8.
Chen HL  Lin KW  Gan KH  Wang JP  Won SJ  Lin CN 《Fitoterapia》2011,82(2):219-224
Two new abietane diterpenoids, ramentoxide (1) and ramentoxidone (2) and a new icetexane diterpenoid, amentonone (3) were isolated from the barks of Amentotaxus formosana. The structures of 1-3 were determined by spectroscopic methods. Known compounds brevitaxin (4), and (+)-ferruginol (5) and ent-kaur-16-en-15-one (6) isolated from this plant revealed potent cytotoxic activity against human breast adenocarcinoma cells, MCF-7 cells with an IC50 value of 0.08 ± 0.05 μg/mL, and significant anti-inflammatory activities, respectively.  相似文献   

9.
Nitrogen (N) is the major nutrient limiting plant growth and production in terrestrial ecosystems around the world. However, nutrient limitation is spatially variable, and different species within the same ecosystem may be limited by different nutrients. N constraints on plant growth have been investigated via fertilization experiments in a variety of ecosystems; however, recently burned coniferous forests are notably under-studied. Given the recent increase in fire activity across western North America, it is important to understand what limits plant growth and carbon sequestration in coniferous forests recovering from wildfire. We evaluated potential inorganic N limitation in four common native plant species, 3–5 years after stand-replacing wildfire in a lodgepole pine forest (Pinus contorta var. latifolia) in Wyoming, USA. Granular reagent grade ammonium nitrate was added around individual plants at a rate equal to the natural background rate of net N mineralization and at 10× this rate. The grass Calamagrostis rubescens exhibited clear evidence of inorganic N limitation: above-ground biomass and shoot:root ratio increased with the high-fertilizer treatment. Nitrogen:phosphorus (N:P) ratio in un-fertilized C. rubescens plants was <14, also consistent with N limitation, but N:P ratio shifted to >16 in the high-fertilizer treatment, suggesting the onset of P limitation. The upland sedge Carex rossii and seedlings of lodgepole pine were not limited by inorganic N: neither species showed any growth response to N fertilization; N:P ratios were only slightly <14; and foliar N concentrations were greater than critical values reported for mature lodgepole pine. The N-fixing forb Lupinus argenteus was not limited by N, for it showed no growth response to fertilization; rather its N:P ratio of 21 indicated P limitation. In this study, to our knowledge the first experimental evaluation of N limitation in subalpine coniferous forests following wildfire, N limitation was seen in only one of four species tested.  相似文献   

10.
由于人工林面积的不断扩大和人类经营措施的不合理,致使世界范围内人工林地力衰退现象十分严重.我国主要造林树种杉木(Cunninghamia lanceolata(Lamb.) Hook)、落叶松(Larix spp.)、桉树(Eucalyptus spp.)等存在地力衰退现象[1-4],其中田大伦[5]、杨玉盛[6]、叶绍明[7]等分别对杉木、桉树连栽进行了较深入研究,得出连栽林地土壤理化性质、林下植物、枯落物生物量及养分循环等有下降趋势.  相似文献   

11.
Zeng X  Qiu Q  Jiang C  Jing Y  Qiu G  He X 《Fitoterapia》2011,82(4):609-614
Three new flavanes and eight known flavonoids were isolated from the fruits of Livistona chinensis. The structure of the new flavanes were established as 2S,3S-3,5,7,3′,5′-pentahydroxyflavane (1), 2R,3R-3,5,6,7,8,4′-hexahydroxyflavane (2) and 2R,3R-3,5,6,7,8,3′,5′-heptahydroxyflavane (3), respectively, on the basis of chemical and spectroscopic data. The antiproliferative activity against four human tumor cell lines (HL-60, Mata, HepG2 and CNE-1) was evaluated. 1 had significantly antiproliferative effects against HL-60 and CNE-1 with the IC50 of 0.2 ± 0.01 and 1.0 ± 0.1 μM, respectively, overpowering the reference compound in the assay (cisplatin). Most compounds also exhibited potent antioxidant activity.  相似文献   

12.
Eryngium foetidum L. is a biennial herb which is used extensively as a medicinal plant in most tropical regions. It is of increasing importance as a spice plant cultivated in India, Vietnam, Australia and elsewhere with well documented procedures for maximum yield. It also possesses a wide range of ethnomedicinal uses including treatment for burns, earache, fevers, hypertension, constipation, fits, asthma, stomach ache, worms, infertility complications, snake bites, diarrhea and malaria. Chemical evaluation of the leaves indicated the presence of flavonoids, tannins, a saponin and several triterpenoids; but no alkaloids were reported. A significant constituent of the essential oil of the plant is E-2-dodecenal ("eryngial"), with isomers of trimethylbenzaldehyde being present in lesser proportions. Variability in the composition of essential oil was clearly dependent on the geographic location of the growing plant. Pharmacological studies of the aerial plant parts have demonstrated anthelmintic activity due to eryngial, anti-inflammatory action due to the phytosterol fractions, anti-convulsant activity in the respective models, and selective antibacterial activity against Salmonella species and the Erwinia genus of bacteria. A fraction of the essential oil rich in eryngial is the subject of a US patent application for its effectiveness against parasitic trypanosomes, nematodes, fungi and bacteria in humans and other mammals. These findings suggest the need for further research of this herb and its products.  相似文献   

13.
Three biphenanthrene compounds (13) and a triphenanthrene compound (4), together with six known biphenanthrene compounds (510), were isolated from the tubers of Monomeria barbata Lindl. Their structures were elucidated on the basis of extensive spectroscopic analysis (1D-, 2D-NMR, and HR-ESI-MS). These four new compounds were tested in vitro for the cytotoxic activity against liver carcinoma (HepG-2), promyelocytic leukaemia (HL60), ovarian carcinoma (Skov-3) and epidermoid carcinoma (A431) cancer cell lines and the antioxidant activity in DPPH radical scavenging. Compounds 14 exhibited significant cytotoxic activity against HepG-2 and HL60 cell lines, and potent antioxidant activity in DPPH radical scavenging.  相似文献   

14.
This work deals with the evaluation of in vitro antioxidant, DNA preventing and antiamoebic activities of the water extracts of Teucrium polium and Stachys iberica. In all systems, T. polium extract exhibited excellent activity potential than that of S. iberica. The amount of total phenolics and flavonoids were high in this extract. In the presence of 40 mg/ml T. polium extract, a significant protection was observed for native super coiled DNA of pBR322 plasmid DNA. In the presence of 32 mg/ml of T. polium extract, no trophozoite was after the 24th hour.  相似文献   

15.
Rapid micropropagation of Nepeta rtanjensis, N. sibirica and N. nervosa was performed. Qualitative and quantitative nepetalactone content in methanol extracts of in vitro grown plants was analysed by reverse-phase HPLC coupled with UV and MS detection. Only trans,cis-nepetalactone was detected in shoots of N. rtanjensis, while cis,trans-nepetalactone stereoisomer was present in N. sibirica. No nepetalactone was observed in shoots of N. nervosa. The antimicrobial activity of methanol extracts, against eight bacterial and eight fungal species, was evaluated. All the tested extracts showed significant antibacterial and strong antifungal activity. However, N. rtanjensis extract exhibited the best antimicrobial potential.  相似文献   

16.
The larval stages of Frankliniella occidentalis Pergande (Thysanoptera: Thripidae) cause more direct feeding damage to plants than the adults. We, therefore, investigated the behaviour-modifying effects on second instar larvae of two jasmonic acid derivatives. The artificial application of methyl jasmonate and cis-jasmone, both at 1 % concentration, deterred the larvae from settling in a dual choice bean leaf disc assay. We observed a dose-dependent feeding deterrence of both jasmonates and calculated the concentration required to reduce the feeding damage by 50 % relative to the control treatment (FDC50) for each jasmonate. The feeding damage was reduced by the application of cis-jasmone at 1 % concentration, but not by the jasmonates at the respective FDC50 in no-choice leaf disc bioassays. However, significantly more larvae left jasmonate-treated whole potted bean plants by migrating to the soil compared with control plants. Our results may be exploited extending behavioural manipulation by using plant compounds in thrips control programmes to the full lifecycle of the pest. Plant compounds could be used in integrated and biological pest management strategies against F. occidentalis in combination with the application of various above and below ground control measures.  相似文献   

17.
Western spruce budworm, Choristoneura occidentalis Freeman, larvae on small Douglas-fir (Pseudotsuga menziesii var. glauca [Beissn.] Franco) and western larch (Larix occidentalis Nutt.) trees were protected from ant and bird predation during fourth instar to pupation. Significantly greater budworm densities were found on protected trees than on the controls at the end of the experiment, and significantly greater feeding injury was associated with increased budworm densities on fir. It is concluded that ants and birds remove budworm larvae feeding on small conifer trees and reduce injury up to 50%.  相似文献   

18.
Two new neo-clerodane diterpenoids have been isolated from the whole plant of Scutellaria barbata D. Don, and their structures were established by detailed spectral analyses as scutehenanine H (1) and 6-(2,3-epoxy-2-isopropyl-n-propoxyl)barbatin C (2). In vitro, the isolated two new compounds showed significant cytotoxic activities against three human cancer lines, and gave IC50 values in the range OF 2.0-4.2 μΜ.  相似文献   

19.
Two new flavane gallates were isolated from the leaves of Plicosepalus curviflorus. The structure of the new compounds was established as 2S,3R-3,3′,4′,5,7-pentahydroxyflavane-5-O-gallate (1) and 2S,3R-3,3′,4′,5,5′,7-hexahydroxyflavane-4′,5-di-O-gallate (2), respectively. In addition, seven known compounds (−)-catechin (3), quercetin (4), lupeol (5), β-sitosterol (6), pomolic acid (7), β-sitosterol 3-O-β-d-glucopyranoside (8) and 4-methoxycinnamic acid (9) were reported for the first time from the genus Plicosepalus. Compounds 1, 2 and 3 were investigated for their hypoglycemic activity and showed significant hypoglycemic activity in Swiss Albino mice.  相似文献   

20.
A new natural spiro compound 3,4-dehydrotheaspirone and the known arctiol [1β,6α-dihydroxy-4(14)-eudesmene] were isolated from Juniperus brevifolia. Arctiol is reported for the first time in the Juniperus genus. Their structures were established by 1D, and 2D NMR and MS spectra. Antimicrobial and cytotoxic activities of 1 and several secondary metabolites ,,,,,,,,, previously isolated by our group from J. brevifolia were evaluated and some SAR has been established. The 18-hydroxydehydroabietane (4) displayed great antiproliferative activity against cancer cell lines tested, namely HeLa, A-549 and MCF-7. Compound 4 also presented a significant bactericidal effect against Bacillus cereus at different concentrations tested.  相似文献   

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