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1.
BACKGROUND: Recent studies have focused on materials derived from plant extracts as mite control products against house dust and stored food mites because repeated use of synthetic acaricides had led to resistance and unwanted activities on non‐target organisms. The aim of this study was to evaluate the acaricidal activity of materials derived from Lycopus lucidus against Dermatophagoides farinae, D. pteronyssinus and Tyrophagus putrescentiae. RESULTS: The LD50 values of L. lucidus oil were 2.19, 2.25 and 8.45 µg cm?2 against D. farinae, D. pteronyssinus and T. putrescentiae. The acaricidal constituent of L. lucidus was isolated by chromatographic techniques and identified as 1‐octen‐3‐ol. In a fumigant method against D. farinae, the acaricidal activity of 1‐octen‐3‐ol (0.25 µg cm?2) was more toxic than N,N‐diethyl‐m‐toluamide (DEET) (36.84 µg cm?2), followed by 3,7‐dimethyl‐1‐octen‐3‐ol (0.29 µg cm?2), 1‐octen‐3‐yl butyrate (2.32 µg cm?2), 1‐octen‐3‐yl acetate (2.42 µg cm?2), 3,7‐dimethyl‐1‐octene (9.34 µg cm?2) and benzyl benzoate (10.02 µg cm?2). In a filter paper bioassay against D. farinae, 1‐octen‐3‐ol (0.63 µg cm?2) was more effective than DEET (20.64 µg cm?2), followed by 3,7‐dimethyl‐1‐octen‐3‐ol (1.09 µg cm?2). CONCLUSION: 1‐Octen‐3‐ol and 3,7‐dimethyl‐1‐octen‐3‐ol could be useful as natural agents for the management of three mite species. Copyright © 2011 Society of Chemical Industry  相似文献   

2.
BACKGROUND: Various attempts to control the populations of house‐dust and stored‐food mites have been implemented using synthetic chemicals. Although effective, the repeated use of these chemicals has led to resistance owing to the mite's high reproductive potential and short life cycle. Therefore, this study aimed to develop natural acaricides using oils derived from Leptospermum scoparium JR & G Forst., which may affect the overall biological activity of a mite without adverse effects. Results were compared with those from using benzyl benzoate and N,N‐diethyl‐3‐methylbenzamide (DEET). RESULTS: The LD50 values of L. scoparium oil were 0.54, 0.67 and 1.12 µg cm?2 against Dermatophagoides farinae (Hughes), D. pteronyssinus (Troussart) and Tyrophagus putrescentiae (Schrank) respectively. The active constituent isolated from L. scoparium was identified as leptospermone (6‐isovaleryl‐2,2,4,4‐tetramethyl‐1,3,5‐cyclohexanetrione) by spectroscopic analysis. Based on the LD50 values of leptospermone and its derivatives, the most toxic compound against D. farinae was leptospermone (0.07 µg cm?2), followed by 2,2,4,4,6,6‐hexamethyl‐1,3,5‐cyclohexanetrione (1.21 µg cm?2), benzyl benzoate (10.03 µg cm?2) and DEET (37.12 µg cm?2). Furthermore, similar results were observed when the leptospermone and its derivatives were tested against D. pteronyssinus and T. putrescentiae. CONCLUSIONS: These results indicate that L. scoparium oil‐derived materials, particularly leptospermone and 2,2,4,4,6,6‐hexamethyl‐1,3,5‐cyclohexanetrione, have potential for development as new agents for the control of three species of mite. Copyright © 2008 Society of Chemical Industry  相似文献   

3.
BACKGROUND: The toxicity to adult Dermatophagoides farinae of allyl isothiocyanate identified in horseradish, Armoracia rusticana, oil and another 27 organic isothiocyanates was evaluated using contact + fumigant and vapour‐phase mortality bioassays. Results were compared with those of two conventional acaricides, benzyl benzoate and dibutyl phthalate. RESULTS: Horseradish oil (24 h LC50, 1.54 µg cm?2) and allyl isothiocyanate (2.52 µg cm?2) were highly toxic. Benzyl isothiocyanate (LC50, 0.62 µg cm?2) was the most toxic compound, followed by 4‐chlorophenyl, 3‐bromophenyl, 3,5‐bis(trifluoromethyl)phenyl, cyclohexyl, 2‐chlorophenyl, 4‐bromophenyl and 2‐bromophenyl isothiocyanates (0.93–1.41 µg cm?2). All were more effective than either benzyl benzoate (LC50, 4.58 µg cm?2) or dibutyl phthalate (24.49 µg cm?2). The structure‐activity relationship indicates that types of functional group and chemical structure appear to play a role in determining the isothiocyanate toxicities to adult D. farinae. In the vapour‐phase mortality bioassay, these isothiocyanates were consistently more toxic in closed versus open containers, indicating that their mode of delivery was, in part, a result of vapour action. CONCLUSION: In the light of global efforts to reduce the level of highly toxic synthetic acaricides in indoor environments, the horseradish oil‐derived compounds and the isothiocyanates described herein merit further study as potential acaricides for the control of house dust mite populations as fumigants with contact action. Copyright © 2011 Society of Chemical Industry  相似文献   

4.
BACKGROUND: Plant essential oils have been recognised as an important natural source of insecticide. This study analysed the chemical constituents and bioactivity of essential oils that were isolated via hydrodistillation from Origanum vulgare L. (oregano) and Thymus vulgaris L. (thyme) against eggs, second instar and adults of Nezara viridula (L.). RESULTS: The major component of oregano was p‐cymene, and, for thyme, thymol. The ovicidal activity was tested by topical application; the essential oil from thyme was more effective. The fumigant activity was evaluated in an enclosed chamber; the LC50 values for oregano were 26.8 and 285.6 µg mL?1 for nymphs and adults respectively; for thyme they were 8.9 µg mL?1 for nymphs and 219.2 µg mL?1 for adults. To evaluate contact activity, a glass vial bioassay was used; the LC50 values for oregano were 1.7 and 169.2 µg cm?2 for nymphs and adults respectively; for thyme they were 3.5 and 48.8 µg cm?2 respectively. The LT50 analyses for contact and fumigant bioassays indicated that thyme was more toxic for nymphs and adults than oregano. Both oils produced repellency on nymphs and adults. CONCLUSION: These results showed that the essential oils from O. vulgare and T. vulgaris could be applicable to the management of N. viridula. Copyright © 2011 Society of Chemical Industry  相似文献   

5.
Han J  Kim SI  Choi BR  Lee SG  Ahn YJ 《Pest management science》2011,67(12):1583-1588
BACKGROUND: This study was aimed at assessing the fumigant toxicity of 14 essential oil constituents from lemon eucalyptus, Eucalyptus citriodora Hook, and another ten known compounds to females of acaricide‐susceptible, chlorfenapyr‐resistant, fenpropathrin‐resistant, pyridaben‐resistant and abamectin‐resistant strains of Tetranychus urticae Koch. RESULTS: Menthol (LC50, 12.9 µg cm?3) was the most toxic compound, followed by citronellyl acetate (16.8 µg cm?3), against the susceptible females. High toxicity was also produced by β‐citronellol, citral, geranyl acetate and eugenol (LC50, 21.7–24.6 µg cm?3). The fumigant toxicity of these compounds was almost identical against females from either of the susceptible and resistant strains, indicating that the compounds and acaricides do not share a common mode of action or elicit cross‐resistance. CONCLUSION: Global efforts to reduce the level of highly toxic synthetic acaricides in the agricultural environment justify further studies on materials derived from lemon eucalyptus oil, particularly menthol and citronellyl acetate, as potential acaricides for the control of acaricide‐resistant T. urticae as fumigants with contact action. Copyright © 2011 Society of Chemical Industry  相似文献   

6.
BACKGROUND: Isothiocyanates (ITCs) extracted from Armoracia rusticana Gaertn., May & Scherb. have been shown previously to have insecticidal activity. Allyl isothiocyanate (AITC), a major component of ITCs with high volatility, was therefore extracted using different methods and tested as a fumigant against four major pest species of stored products, maize weevil Sitophilus zeamais (Motsch.), lesser grain borer Rhizopertha dominica (F.), Tribolium ferrugineum (F.) and book louse Liposcelis entomophila (Enderlein). RESULTS: Whereas there was no significant difference between hydrodistillation and supercritical carbon dioxide fluid extraction in extraction rate for AITC from A. rusticana, both methods resulted in higher extraction efficiency than water extraction. AITC fumigation showed strong toxicity to the four species of stored‐product pests. Adult mortality of 100% of all four pest species, recorded after 72 h exposure to AITC fumes at an atmospheric concentration of 3 µg mL?1, showed no significant difference from that of insects exposed to phosphine at 5 µg mL?1, the recommended dose for phosphine. CONCLUSIONS: The results suggest good insecticidal efficacy of AITC against the four stored‐product pests, with non‐gaseous residuals on stored products. AITC obtained from A. rusticana may be an alternative to phosphine and methyl bromide against the four pest species. Copyright © 2009 Society of Chemical Industry  相似文献   

7.
BACKGROUND: As previously reported, methyl (E)‐2‐[2‐(2‐phenylamino‐6‐trifluoromethylpyrimidin‐4‐yloxymethyl)phenyl]‐3‐methoxyacrylate has proven to be a new lead with highly acaricidal activity. Following on from this, in an effort to discover new strobilurin analogues with improved activity, a series of substituted pyrimidines were synthesised and bioassayed. RESULTS: All compounds were characterised by 1H NMR, IR, MS and elemental analysis. Preliminary bioassays demonstrated that some of the title compounds exhibited notable control of Tetranychus cinnabarinus (Boisd.) at 1.25 mg L?1. The relationship between structure and acaricidal activity is discussed. CONCLUSION: Two compounds of particular interest, 6j (SYP‐10913) and 6k (SYP‐11277), exhibited potent acaricidal activity. The acaricidal potencies of these analogues are higher than that of fluacrypyrim in greenhouse applications, and are comparable with those of commercial acaricides such as spirodiclofen and propargite in field trials. Copyright © 2011 Society of Chemical Industry  相似文献   

8.
BACKGROUND: The contact + fumigant toxicity of 92 plant essential oils and control efficacy of 18 experimental spray formulations containing nine selected essential oils (0.5 and 0.1% sprays) and six commercial insecticides to females from B‐ and Q‐biotypes of Bemisia tabaci were evaluated using vapour‐phase mortality and spray bioassays. RESULTS: Garlic and oregano (LC50, 0.15 mL cm?3) were the most toxic oils against B‐ and Q‐biotype females. Strong fumigant toxicity to both biotype females was also obtained from catnip, cinnamon bark, clove bud, clove leaf, davana, savory and vetiver Haiti oils (LC50, 0.17–0.48 mL cm?3). The 0.5% sprays of these oils (except for thyme red oil) resulted in 90–100% mortality against both biotype females. Only garlic applied as 0.1% spray provided 100% mortality. Spinosad 100 g L?1 suspension concentrate (SC) treatment resulted in 92 and 95% mortality against both biotype females, whereas acetamiprid 80 g L?1 wettable powder (WP), imidacloprid 80 g L?1 SC, thiamethoxam 100 g L?1 water‐dispersible granule (WDG) and pyridaben 200 g L?1 WP treatments resulted in 89–100% mortality against B‐biotype females only. CONCLUSION: In the light of global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment, the essential oils described, particularly garlic, cinnamon bark and vetiver Haiti, merit further study as potential insecticides for the control of B. tabaci populations as fumigants with contact action. Copyright © 2011 Society of Chemical Industry  相似文献   

9.
We synthesized 33 new phenylpiperazine derivatives and assessed their acaricidal activity. These derivatives were synthesized through sequential reactions consisting of the sulfonylation of 2-substituted 4-methylaniline with chlorosulfonic acid, reduction with red phosphorus and iodine, alkylation by alkyl halide, cyclization with bis(2-chloroethyl)amine hydrochloride, and N-substitution reaction of phenylpiperazines with various reagents. All phenylpiperazines synthesized were evaluated for acaricidal activity and their structure–activity relationships discussed, it was found that 4-substituted 1-[2-fluoro-4-methyl-5-(2,2,2-trifluoroethylsulfanyl)phenyl]piperazine derivatives exhibited good acaricidal activity. Among them, 1-[2-fluoro-4-methyl-5-(2,2,2-trifluoroethylsulfanyl)phenyl]-4-(trifluoromethylsulfonyl) piperazine showed the highest level of activity against Tetranychus urticae and provided a high level of activity against Tetranychus kanzawai and Panonychus citri. In addition, studies on the effect at various stages of T. urticae exhibited that this compound showed good activity against both adults and eggs.  相似文献   

10.
Isomers of pyrethroids usually have different insecticidal activities. Permethrin, a non‐cyano pyrethroid, is not an exception and cis‐permethrin is much more active than the trans‐isomer against Triatoma infestans, vector of Chagas' Disease in Argentina. The large‐scale separation of cis‐ and trans‐permethrin was performed by successive recrystallizations from ethanol‐water mixtures. An aqueous suspension concentrate (flowable) formulation of pure crystalline cis‐permethrin was prepared and assayed for its insecticidal activity on wood and ceramic surfaces against nymph V of T infestans. This formulation was at least three times more effective than deltamethrin, with LC50 values on ceramic of 0.11 µg cm−2 and 0.33 µg cm−2 respectively. On wood surfaces, the LC50 value was 0.57 µg cm−2 compared with 3.20 µg cm−2 for deltamethrin. Against other insect species such as Periplaneta americana, Aedes aegypti and Culex quinquefasciatus, the suspension concentrate formulation of cis‐permethrin was, however, less effective than similar formulations of deltamethrin or β‐cypermethrin. © 2000 Society of Chemical Industry  相似文献   

11.
BACKGROUND: The granary weevil, Sitophilus granarius (L.), is one of the most damaging pests of stored grains, causing severe quantitative and qualitative losses. Sustainable control means, alternative to the commonly used fumigants and broad‐spectrum contact insecticides, are urgently needed owing to legislative limits, the development of resistant insect strains and increasing consumer demand for safe food. Short‐chain aliphatic ketones, known to be emitted by cereal grains and previously identified as repellents to adult granary weevils, were evaluated for their ability to disrupt insect orientation towards wheat grains and as possible natural fumigants. RESULTS: In behavioural bioassays, 2‐pentanone, 2‐hexanone, 2‐heptanone and 2,3‐butanedione significantly reduced insect orientation towards odours of wheat grains, with 2‐hexanone and 2‐heptanone being the most active. In fumigation tests, all compounds were effective in killing weevil adults, but they performed differently according to chemical structure, speed of action and presence of wheat grains. In the presence of grains, the highest fumigant toxicity was shown by 2‐pentanone (LC50 = 8.4 ± 1.0 mg L?1) after 24 h exposure, and by 2‐pentanone (LC50 = 4.5 ± 0.3 mg L?1), 2‐heptanone (LC50 = 7.1 ± 0.3 mg L?1) and 2‐hexanone (LC50 = 8.1 ± 0.6 mg L?1) 1 week after the treatment end. CONCLUSION: Short‐chain aliphatic ketones have potential for applications in IPM programmes for the granary weevil because of their behaviour‐altering activity and fumigant toxicity. Copyright © 2011 Society of Chemical Industry  相似文献   

12.
BACKGROUND: The small number of available nematicides and restrictions on the use of non‐fumigant nematicides owing to high toxicity to human and non‐target organisms hinder effective nematode control. The nematicidal efficacy of MCW‐2, a new nematicide of the fluoroalkenyl group, was evaluated against the root‐knot nematode Meloidogyne javanica (Treub.) Chitwood. RESULTS: MCW‐2 showed irreversible nematicidal activity against second‐stage juveniles of M. javanica in vitro, following exposure for 48 h at concentrations as low as 0.5 mg L?1, in contrast to fenamiphos or cadusafos. When exposed to MCW‐2 for shorter periods, motile juveniles became immobile with time after rinsing in water. MCW‐2 at 8 mg L?1 inhibited nematode hatching, which, however, recovered after rinsing in water. In pot and plot experiments, 0.5 mg MCW‐2 L?1 soil and 2 kg MCW‐2 ha?1, respectively, controlled M. javanica similarly to or better than fenamiphos or cadusafos at the same concentrations or at their recommended doses. In the soil, the nematicidal activity of MCW‐2 was less persistent than that of fenamiphos. CONCLUSION: MCW‐2 has potential to be used as a new non‐fumigant nematicide that probably has a novel mode of action. Copyright © 2009 Society of Chemical Industry  相似文献   

13.
BACKGROUND: Most insecticides used to control rice water weevil (Lissorhoptrus oryzophilus Kuscel) infestations are pyrethroids. However, pyrethroids are highly toxic to non‐target crayfish associated with rice–crayfish crop rotations. One solution to the near‐exclusive reliance on pyrethroids in a rice–crayfish pest management program is to incorporate neonicotinoid insecticides, which are insect specific and effective against weevils but not extremely toxic to crayfish. This study aimed to take the first step to assess neonicotinoids as alternatives to pyrethroids in rice–crayfish crop rotations by measuring the acute toxicities of three candidate neonicotinoid insecticides, clothianidin, dinotefuran and thiamethoxam, to juvenile Procambarus clarkii (Girard) crayfish and comparing them with the acute toxicities of two currently used pyrethroid insecticides, lambda‐cyhalothrin and etofenprox. RESULTS: Neonicotinoid insecticides are at least 2–3 orders of magnitude less acutely toxic (96 h LC50) than pyrethroids to juvenile Procambarid crayfish: lambda‐cyhalothrin (0.16 µg AI L?1) = etofenprox (0.29 µg AI L?1) ? clothianidin (59 µg AI L?1) > thiamethoxam (967 µg AI L?1) > dinotefuran (2032 µg AI L?1). CONCLUSION: Neonicotinoid insecticides appear to be much less hazardous alternatives to pyrethroids in rice–crayfish crop rotations. Further field‐level neonicotinoid acute and chronic toxicity testing with crayfish is needed. Copyright © 2009 Society of Chemical Industry  相似文献   

14.
The present study investigated the arsenic (As) remediation potential of barnyard grass (Echinochloa crus‐galli L. Beauv. var. formosensis Ohwi), with a special focus on the behavior of As in the soil in comparison with rice (Oryza sativa L. cv. Nipponbare). For both plants, very little growth inhibition was observed in the As‐contaminated soil. The amount of As in the soil was reduced by the plant's uptake and the level of As in the soil water from the rice‐growing pots was remarkably lower than that in the plant‐free soil water. In the soil with the barnyard grass, the amount of As in the soil water was higher than that in the plant‐free soil water, but the amount of As in the soil and the amount of As that was adsorbed on the soil solid were reduced by the plant's uptake. At the highest As level in the soil (100 mg kg?1), 249.60 and 101.26 µg As pot?1 were taken up by the rice shoot and barnyard grass shoot, respectively, and total amounts of 1468.65 and 1060.57 µg As pot?1 were taken up by the barnyard grass and rice seedlings, respectively. At the same As level in the soil, the As concentrations were 14.99 and 37.76 µg g?1 in the shoot of barnyard grass and rice, respectively, and 486.61 and 339.32 µg g?1 in the root of barnyard grass and rice, respectively. Barnyard grass took up more As than rice, but the As concentration in the shoot of barnyard grass was lower than that in the shoot of rice. A considerable amount of As was taken up by both barnyard grass and rice, suggesting that the plant species have the potential to remediate As‐contaminated soil.  相似文献   

15.
BACKGROUND: The repellency to stable fly, Stomoxys calcitrans (L.), of Zanthoxylum piperitum (L.) DC pericarp steam distillate (ZP‐SD), Zanthoxylum armatum DC seed oil (ZA‐SO) and their constituents alone or in combination with Calophyllum inophyllum L. nut oil (CI‐NO), as well as six aerosol formulations containing ZP‐SD or ZP‐SO and CI‐NO, was compared with that of a synthetic repellent, DEET, using an exposed human hand bioassay. RESULTS: At 0.20 mg cm?2, ZP‐SD treatments resulted in 91 and 68% repellency following 30 and 60 min exposure respectively, while DEET gave 100 and 84% repellency. ZA‐SO was less effective than ZP‐SD. At 0.2 mg cm?2, the most active constituents, cuminaldehyde, cuminyl alcohol, limonene and methyl cinnamate, gave 82, 74, 74 and 64% repellency at 30 min respectively, but DEET gave 100 and 87% repellency at 30 and 60 min. An increase in effectiveness and duration of repellency was produced by binary mixtures of ZP‐SD, ZA‐SO or bioactive constituents (each 0.01 mg cm?2) and CI‐NO (0.99 mg cm?2). The repellency of aerosols containing 2.5% ZP‐SD or 2.5% ZA‐SO and 2.5% CI‐NO was comparable with that of 5% DEET aerosol. CONCLUSION: Mixtures formulated from ZP‐SD, ZA‐SO or bioactive constituents and CI‐NO could be useful as potential repellents for the control of stable fly populations in light of global efforts to reduce the level of highly toxic synthetic repellents. Copyright © 2010 Society of Chemical Industry  相似文献   

16.
Emission of methyl isothiocyanate (MITC) from fields treated with metam‐sodium (sodium N‐methyldithiocarbamate) is a potential environmental and human safety hazard. Concentrations of MITC at three heights above four arable fields were measured following the application of metam‐sodium at a rate of 480 litre ha−1 (166 kg AI ha−1). Two of these fields were treated by injection into a center‐pivot irrigation system (chemigation), while in the other two fields the fumigant was applied through injection directly into the soil. Generally, higher MITC air concentrations were observed above chemigated than above injected fields. Maximum MITC air concentrations were 11.2 and 7.4 µg m−3 recorded 10 cm above ground 6–8 h following application and the minimum concentrations were 0.7 and 0.2 µg m−3 observed at 200 cm 30–35 h after application above chemigated and injected fields, respectively. The estimated MITC respiratory exposure a worker might encounter during the re‐entry period ranged between 1.37 and 0.03 mg day−1 in chemigated fields and between 0.35 and 0.02 mg day−1 in the injected fields. These results suggest that application of the fumigant through injection reduced MITC volatilization losses in comparison with the chemigation method, thus posing a relatively lower risk of exposure to MITC emissions. © 2000 Society of Chemical Industry  相似文献   

17.
The insecticidal activities of materials derived from the fruit of fennel, Foeniculum vulgare, against adults of Sitophilus oryzae, Callosobruchus chinensis and Lasioderma serricorne were examined using direct contact application and fumigation methods. The biologically active constituents of the Foeniculum fruits were characterized as the phenylpropenes (E)‐anethole and estragole, and the monoterpene (+)‐fenchone, by spectroscopic analysis. Responses varied with insect species, compound, dose and exposure time. In a filter paper diffusion test, estragole at 0.168 mg cm?2 caused 91% mortality to S oryzae adults within 1 day after treatment (DAT), whereas (+)‐fenchone and (E)‐anethole gave over 90% mortality at 2 and 4 DAT, respectively. Against C chinensis adults, all test compounds revealed potent insecticidal activities at 0.021 mg cm?2 at 2 DAT. Against L serricorne adults at 0.105 mg cm?2, (E)‐anethole gave 100% mortality at 1 DAT, whereas 90 and 60% mortality at 4 DAT was achieved with estragole and (+)‐fenchone, respectively. In a fumigation test, the test compounds were much more effective against adults of S oryzae, C chinensis and L serricorne in closed cups than in open ones, indicating that the insecticidal activity of test compounds was largely attributable to fumigant action. As naturally occurring insect‐control agents, the F vulgare fruit‐derived materials described could be useful for managing field populations of S oryzae, C chinensis and L serricorne. © 2001 Society of Chemical Industry  相似文献   

18.
BACKGROUND: The intermediate derivatisation method based on bioisosteric replacement led to the discovery of the lead strobilurin compound 5a. To produce new strobilurin analogues with improved activity, a series of substituted pyrimidines were synthesised and bioassayed. RESULTS: The compounds were identified by 1H NMR, IR, MS and elemental analysis. The highly active compound 5g was studied by X‐ray diffraction. Preliminary bioassays demonstrated that some of the title compounds exhibited excellent acaricidal activity against Tetranychus cinnabarinus (Boisd.) at 10 mg L?1. The relationship between structure and acaricidal activity is reported. CONCLUSION: The present work demonstrates that strobilurin derivatives containing pyrimidine moieties can be used as possible lead compounds for developing novel acaricides. Copyright © 2010 Society of Chemical Industry  相似文献   

19.
BACKGROUND: Triterpenic saponins from Sapindus mukorossi Gaertn. and Diploknema butyracea JF Gmelin were evaluated for in vitro antifungal activity against four phytopathogenic fungi. The study of the structure–antifungal activity relationships of protobassic acid saponins was widened by including semi‐synthetic derivatives. RESULTS: Diploknema butyracea saponins exhibited significant antifungal activity against three fungi (ED50 230–455 µg mL?1), whereas S. mukorossi saponin was effective against two fungi (ED50 181–407 µg mL?1). The n‐butanol extract after preparative HPLC separation provided two saponins from D. butyracea saponin mixture: 3‐O‐[β‐D ‐glucopyarnosyl‐β‐D ‐glucopyranosyl]‐16‐α‐hydroxyprotobassic acid‐28‐O‐[arabinopyranosyl‐glucopyranosyl‐xylopyranosyl]‐arabinopyranoside (MI‐I), and 3‐O‐β‐D ‐glucopyranosyl‐glucopyranosyl‐glucopyranosyl‐16‐α‐hydroxyprotobassic acid‐28‐O‐[arabinopyranosyl‐xylopyranosyl‐arabinopyranosyl]‐apiofuranoside (MI‐III). The single saponin extracted from S. mukorossi saponin mixture was identified as 3‐O‐[O‐acetyl‐β‐D ‐xylopyranosyl‐β‐D ‐arabinopyranosyl‐β‐D ‐rhamnopyranosyl] hederagenin‐28‐O[β‐D ‐glucopyranosyl‐β‐D ‐glucopyranosyl‐β‐D ‐rhamnopyranosyl] ester (SM‐I). Monodesmosides resulting from the partial degradation of hederagenin and hydroxyprotobassic acid bisdesmosides exhibited significant reduction in antifungal effect. Further removal of sugar moiety yielded complete loss in activity. The antifungal activity of the triterpenic saponins was associated with their aglycone moieties, and esterification of the hydroxyl group led to change in antifungal activity. CONCLUSION: Sapindus mukorossi saponin, which is effective against Rhizoctonia bataticola (Taub.) Briton Jones and Sclerotium rolfsii Sacc., can be exploited for the development of a natural fungicide. A sugar moiety is a prerequisite for the antifungal activity of triterpenic saponin. Copyright © 2010 Society of Chemical Industry  相似文献   

20.
BACKGROUND: Biorational means for phytonematode control were studied within the context of an increasingly ecofriendly pest management global approach. The nematicidal activity and the chemical composition of essential oils (EOs) isolated from seven plants grown in Greece and ten selected compounds extracted from them against second‐stage juveniles (J2) of Meloidogyne incognita (Kof. & White) Chitwood were evaluated using juvenile paralysis experiments. Additionally, synergistic and antagonistic interactions between nematicidal terpenes were studied using an effect addition model, with the comparison made at one concentration level. RESULTS: The 96 h EC50 values of Foeniculum vulgare Mill., Pimpinella anisum L., Eucalyptus meliodora A Cunn ex Schauer and Pistacia terebinthus L. were 231, 269, 807 and 1116 µg mL?1, respectively, in an immersion bioassay. Benzaldehyde (9 µg mL?1) was the most toxic compound, followed by γ‐eudesmol (50 µg mL?1) and estragole (180 µg mL?1), based on 96 h EC50 values. The most potent terpene pairs between which synergistic actions were found, in decreasing order, were: trans‐anethole/geraniol, trans‐anethole/eugenol, carvacrol/eugenol and geraniol/carvacrol. CONCLUSION: This is the first report on the activity of F. vulgare, P. anisum, E. meliodora and P. terebinthus, and additionally on synergistic/antagonistic nematicidal terpene interactions, against M. incognita, providing alternative methods for nematode control. Copyright © 2010 Society of Chemical Industry  相似文献   

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