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1.
The anthelmintic effect of Khaya senegalensis is described. In vitro and in vivo studies were conducted to determine possible direct anthelmintic effects of ethanolic and aqueous extracts of K. senegalensis towards different ovine gastrointestinal nematode. A larval development assay was used to investigate in vitro, the effect of aqueous and ethanolic extracts towards larvae of strongyles. The LC50 values of the effects of both the aqueous and ethanolic extracts were calculated. Another study was conducted in vivo to evaluate the therapeutic efficacy of the extracts administered orally at a dose rate of 125, 250 and 500 mg/kg of sheep harbouring naturally acquired infection of gastrointestinal nematodes. The presence of K. senegalensis extracts in the cultures decreased the viability of larvae. The LC50 of the aqueous extract (0.69 mg/ml) is not significantly different (P >0.05, t-test) from the ethanolic extract (0.51 mg/ml). The activity of the extract is concentration dependent in vivo. Sheep drenched with 500 mg/kg K. senegalensis ethanolic extract had a mean faecal egg count (FEC) reduction of 88.82%. The extract of K. senegalensis could find application in anthelmintic therapy in veterinary practice.  相似文献   

2.
Evaluation of anthelmintic effects of Trianthema (T.) portulacastrum L. (Aizoaceae) whole plant and Musa (M.) paradisiaca L. (Musaceae) leaves against prevalent gastrointestinal worms of sheep was done that may justify their traditional use in veterinary clinical medicine. In vitro anthelmintic activity of the crude aqueous methanolic extract (CAME) of both the plants was determined using mature female Haemonchus (H.) contortus and their eggs in adult motility assay (AMA) and egg hatch test (EHT), respectively. In vivo anthelmintic activity of crude powder (CP) and CAME in increasing doses (1.0-8.0 g kg(-1)) was determined in sheep naturally infected with mixed species of nematodes using fecal egg count reduction test (FECRT) and larval counts. The study design also included untreated as well as treated controls. Fecal egg count reduction and larval counts from coprocultures were performed pre- and post-treatments to assess the anthelmintic activity of the plants. CAME of T. portulacastrum and M. paradisiaca showed a strong in vitro anthelmintic activity and pronounced inhibitory effects on H. contortus egg hatching as observed through AMA and EHT, respectively. Both plants exhibited dose and time dependent anthelmintic effects on live worms as well as egg hatching. M. paradisiaca (LC(50)=2.13 μg mL(-1)) was found to be more potent than T. portulacastrum (LC(50)=2.41 μg mL(-1)) in EHT. However, in vivo, maximum reduction in eggs per gram (EPG) of faeces was recorded as 85.6% and 80.7% with CAME of T. portulacastrum and M. paradisiaca at 8.0 g kg(-1) on 15th day post-treatment, respectively as compared to that of Levamisole (7.5 mg kg(-1)) that caused 97.0% reduction in EPG. All the species of gastrointestinal nematodes (GINs), i.e. Haemonchus contortus, Trichostronglyus spp., Oesophagostomum columbianum and Trichuris ovis which were prevalent, found susceptible (P<0.01) to the different doses of CP and CAME of both plants. The data showed that both T. portulacastrum and M. paradisiaca possess strong anthelmintic activity in vitro and in vivo, thus, justifying their use in the traditional medicine system of Pakistan.  相似文献   

3.
Wang Y  Wu ZF  Wang GX  Wang F  Liu YT  Li FY  Han J 《Veterinary parasitology》2011,177(1-2):127-133
The present study was designated to ascertain the anthelmintic activity of the dried fruits of Brucea javanica and to isolate and characterise the active constituents. The methanol extract from the fruits of B. javanica showed significant anthelmintic activity against Dactylogyrus intermedius (EC(50) (median effective concentration) value=49.96 mg l(-1)). Based on this finding, the methanol extract was fractionated on silica gel column chromatography in a bioassay-guided fractionation affording two known quassinoids showing potent activity, bruceine A and bruceine D. Both bruceine A and D exhibited significant activity against D. intermedius with EC(50) values of 0.49 mg l(-1) and 0.57 mg l(-1), respectively, which were more effective than the positive control, mebendazole (EC(50) value=1.25 mg l(-1)). In addition, the 48-h median lethal concentration (LC(50)) for bruceine A and D against the host (Carassius auratus) was 10.6-fold and 9.7-fold higher than the EC(50) for D. intermedius. These results provide evidence that the isolated compounds might be potential sources of new anti-parasitic drugs for the control of Dactylogyrus. This is the first report on an in vivo anthelmintic investigation for B. javanica against D. intermedius.  相似文献   

4.
Haemonchus contortus is responsible for severe economic losses in sheep and goat breeding in the Northeast of Brazil. However, the effectiveness of control is compromised due to anthelmintic resistance and misuse. In the search for natural anthelmintics, Melia azedarach L., a plant indigenous to India but now distributed throughout Brazil, was selected due to the reported anthelmintic properties of its seeds. The aim of this study was to evaluate the anthelmintic activity of the seed and leaf extracts of the Brazilian adapted plant and investigate the type of organic chemical compounds present in the most active extracts. The ovicidal and larvicidal activity of M. azedarach extracts on H. contortus was evaluated through egg hatching and larval development tests. Hexane and ethanol extracts of seeds and chloroform and ethanol extracts of leaves of M. azedarach were used in the tests. To perform the larval development test, feces of an animal free from parasites were mixed with third instar H. contortus larvae and extracts in several concentrations. The coprocultures were incubated for 7 days at 30 degrees C, then the larvae were recovered and counted. LC50 was calculated by probits using the SPSS 8.0 program. The seed ethanol extract was the most active on eggs (LC50=0.36mgmL(-1)) and the leaf ethanol extract showed the best inhibition of larval development (LC50=9.18mgmL(-1)). Phytochemical analysis of the most active extracts revealed the presence of condensed tannins, triterpenes and alkaloids.  相似文献   

5.
The indiscriminate use of anthelmintics has resulted in the establishment of parasite resistance. Thus, this study aimed to evaluate the in vitro antiparasitic effect of plant extracts on Haemonchus contortus in sheep and the in vivo effect on Strongyloides venezuelensis in Rattus norvegicus. The plant extracts from Piper tuberculatum, Lippia sidoides, Mentha piperita, Hura crepitans and Carapa guianensis, produced at different research institutions, were chemically analyzed and evaluated through the egg hatch test (EHT) and larval development test (LDT) in H. contortus. P. tuberculatum (150 and 250 mg kg(-1) of body weight) was evaluated for its anthelmintic action on R. norvegicus experimentally infected with S. venezuelensis. In the EHT, the LC(50) and LC(90) of the extracts were respectively as follows: 0.031 and 0.09 mg mL(-1) for P. tuberculatum, 0.04 and 0.13 mg mL(-1) for L. sidoides, 0.037 and 0.10 mg mL(-1) for M. piperita, 2.16 and 17.13 mg mL(-1) for H. crepitans and 2.03 × 10(-6) and 1.22 × 10(-12) mg mL(-1) for C. guianensis. In the LDT, the LC(50) and LC(90) were respectively: 0.02 and 0.031 mg mL(-1) for P. tuberculatum, 0.002 and 0.04 mg mL(-1) for L. sidoides, 0.018 and 0.03 mg mL(-1) for M. piperita, 0.36 and 0.91 mg mL(-1) for H. crepitans and 17.65 and 1890 mg mL(-1) for C. guianensis. The extract of P. tuberculatum showed the following substances: piperamides as (Z)-piplartine, (E)-piplartine, 8,9-dihydropiplartine, piperine, 10,11-dihydropiperine, 5,6 dihydropiperlongumine and pellitorine. The major compounds of the oils were thymol (76.6%) for L. sidoides, menthol (27.5%) for M. piperita and oleic acid (46.8%) for C. guianensis. Regarding the in vivo test, neither dose of P. tuberculatum caused any significant reduction (P>0.05) in worm burden and fecal egg counts compared with the control group. We conclude that the extracts of P. tuberculatum, L. sidoides and M. piperita have effective activity when tested in vitro, but the doses of the extract of P. tuberculatum have no effect when employed in in vivo tests.  相似文献   

6.
This study was carried out to validate the efficacy of Spondias mombin, used locally as an anthelmintic, and to standardize the effective dose of the plant extract required for worm control in livestock. In vitro and in vivo studies were conducted to determine the direct anthelmintic effect of ethanolic and aqueous extracts of S. mombin towards different ovine gastrointestinal nematodes. A larval development assay (LDA) was used to investigate the in vitro effect of extracts on strongyle larvae. Another study was conducted in vivo to evaluate the therapeutic efficacy of the extracts administered orally at dose rates of 125, 250, 500 mg/kg to sheep naturally infected with gastrointestinal nematodes. Twenty sheep were selected on the basis of positive faecal egg counts (750 epg). The sheep were allocated randomly to a non-medicated control group (A) or to groups given 125 mg/kg (B), 250 mg/kg (C) or 500 mg/kg (D) of extract, respectively. Sheep in groups B-D were given extracts orally on two days. Individual faecal egg counts were performed on days 0, 3, 6, 9 and 12. The presence of S. mombin extracts in in vitro cultures of larvae decreased the survival of L3 larvae. The LC50 of the aqueous extract of S. mombin was 0.907 mg/ml, while the LC50 of the ethanolic extract was 0.456 mg/ml. This difference in LC50 was statistically significant (p > 0.05). The mean percentage faecal egg reduction of sheep drenched with 500 mg/kg S. mombin extracts was 15.0%, 27.5%, 65.0%, 65.0%, 100.0% against Haenmonchus spp., Trichostrongylus spp., Oesophagostomunm spp., Strongyloides spp. and Trichuris spp. respectively, on day 12. Extracts of S. mombin could find application in the control of helminths in livestock.  相似文献   

7.
Hao B  Liu GL  Hu XG  Wang GX 《Veterinary parasitology》2012,187(3-4):452-458
The present study was undertaken to isolate the active compounds responsible for the anthelmintic activity of methanol extract of Semen pharbitidis against Dactylogyrus intermedius in goldfish (Carassius auratus). The active methanol extract was fractionated on silica gel column chromatography in a bioassay-guided fractionation, eventually yielding two bioactive compounds: palmitic acid and pharnilatin A by comparing spectral data (NMR and ESI-MS) with literature values. According to in vivo anthelmintic assays, they were found to be 50% effective at the concentrations (EC(50)) of 5.3 and 1.4 mg L(-1), respectively. The promising palmitic acid and pharnilatin A from S. pharbitidis were also subjected to acute toxicity tests for the evaluation of their safety to the host (goldfish). After 48h exposure, the mortalities of goldfish were recorded, and the established LC(50) values were 2.45- and 5.29-fold higher than the corresponding EC(50), demonstrating that pharnilatins A may have better application potential than palmitic acid. The present results provide evidence that pharnilatins A might be potential source of new anti-parasitic drug for the control of Dactylogyrus.  相似文献   

8.
Many plants are used for ethnoveterinary purposes in South Africa, particularly in rural areas. Extracts of 17 plant species employed to treat infectious diseases were prepared using three solvents and the antibacterial activity of the extracts was determined against two Gram-positive and two Gram-negative bacteria. Anthelmintic activity was evaluated against the free-living nematode Caenorhabditis elegans and toxicity was determined using the brine shrimp larval mortality test. Most of the plant extracts demonstrated antibacterial activity, with the best minimum inhibitory concentration (MIC) being 0.1 mg mL(-1). More than a third of the extracts displayed anthelmintic activity. Toxic effects against brine shrimp larvae were shown by 30% of extracts, with the lowest LC(50) recorded as 0.6 mg mL(-1). The promising biological activity displayed by a number of plant extracts supports the ethnoveterinary use of these plants but in vivo tests are required to ascertain fully their medicinal properties and potential toxicity.  相似文献   

9.
The development of anthelmintic resistance has impacted on the success of conventional anthelmintics (AH) for the control of gastrointestinal nematodes in grazing/browsing sheep and goats. Medicinal plants from the traditional herbolary in Mexico may provide new candidates that can be explored as alternative sources of AHs for ruminants. This study evaluated the leaf extracts derived from Phytolacca icosandra against infective L(3) larvae and eggs from Haemonchus contortus collected from sheep. Three extracts of different polarities were obtained from the leaf plants using ethanol, n-hexane and dichloromethane as the solvents. The effectiveness of the in vitro AH activity of the plant extracts was evaluated using larval migration inhibition (LMI) and egg hatch (EHA) assays. For the LMI assays, the ethanolic extract of P. icosandra showed 55.4% inhibition of larval migration at 2mg/mL (p<0.05). The dichloromethane extract of P. icosandra showed 67.1% inhibition of migration at 3mg/mL (p<0.05) and a dose-dependent response with an LD(50) of 0.90 mg/mL. The n-hexane extract failed to show inhibition of larval migration at any concentration explored. In the EHA for the ethanol extract, the lowest concentration tested (0.15 mg/mL) resulted in inhibition of egg hatching greater than 72.6%. Therefore, the LD(50) could not be calculated for this extract. The LD(50) of the dichloromethane extract of P. icosandra was 0. 28 mg/mL. An egg hatch inhibition greater than 90% was observed with both the ethanolic and dichloromethane extracts when using a concentration of 0.90 mg/mL or higher. The n-hexane extract failed to show egg hatch inhibition at any concentration tested. The AH activity reported for P. icosandra could be attributable to the flavonoids, steroids, terpenoids, coumarins and/or saponins that were present in the ethanolic and dichloromethane extracts. A combination of more than one component may also explain the observed AH activity against the H. contortus life stages that were evaluated. In conclusion, the ethanolic and dichloromethane extracts of P. icosandra showed clear in vitro AH activity against the H. contortus eggs and the L(3) larvae. However, the hexanic extract of the plant leaves failed to show any in vitro AH activity.  相似文献   

10.
Viral infections remain a major threat to humans and animals and there is a crucial need for new antiviral agents especially with the development of resistant viruses. The hexane, dichloromethane, acetone and methanol extracts of six plant species selected for their traditional use against infections were tested for in vitro antiviral activity against canine distemper virus (CDV), canine parainfluenza virus-2 (CPIV-2), feline herpesvirus-1 (FHV-1) and lumpy skin disease virus (LSDV). All extracts were tested for their cytotoxicity using a colorimetric tetrazolium-based (MTT) assay and were tested for antiviral efficacy at concentrations below CC(50) values on the various cell types used in this study. The antiviral activity of extracts was tested using virucidal and attachment assays. In the virucidal assay, extracts were incubated with virus prior to infection. The most potent inhibition was observed with the acetone and methanol extracts of Podocarpus henkelii against CDV and LSDV, which inhibited replication of the viruses by >75% at 3μg/ml with selectivity index (SI) values ranging between 12 and 45. Excellent activity was also found with the hexane extracts of Plumbago zeylanica and Carissa edulis against CDV, with the extracts reducing viral-induced CPE by 50% and 75% respectively. The hexane extract of C. edulis had moderate activity against FHV-1 with EC(50)<70μg/ml and SI value <2. Only the acetone extract of P. henkelii moderately inhibited replication of LSD virus in the attachment assay, with low activity in other extracts. Of the four extracts with significant antiviral activity, two were prepared from P. henkelii. Therefore, future work will focus on isolating and characterizing the substance(s) responsible for bioactivity in extracts of this species.  相似文献   

11.
The anthelmintic potentials of the aqueous and methanol extracts of Euphorbia helioscopia were investigated. In folklore medicine, E. helioscopia (Euphorbiaceae) is used in the treatment of various gastrointestinal ailments and diseases. A worm motility inhibition (WMI) assay and egg hatch assay (EHA) were used for in vitro assessment, and a faecal egg count reduction (FECR) assay was used for an in vivo study. The in vitro study revealed anthelmintic effects of crude methanolic extracts of E. helioscopia on live Haemonchus contortus worms as evident from their paralysis and/or death at 8h after exposure, different concentrations (12.5mgml(-1), 25mgml(-1) and 50mgml(-1)) of aqueous and methanolic extracts were used against H. contortus which exhibited dose-dependent anthelmintic effects on H. contortus. Aqueous and methanolic extracts of aerial parts (stem, leaves and flowers) of E. helioscopia were found to have very low percent inhibitory egg hatching as compared to levamisole. It is concluded that the entire plant of E. helioscopia possesses significant anthelmintic activity and could be a potential alternative for treating cases of helminth infections in ruminants.  相似文献   

12.
The present study was based on assessments of the antiparasitic activity to determine the efficacies of hexane, chloroform, ethyl acetate, acetone, methanol and aqueous leaf extracts of Euphorbia prostrata Ait. (Euphorbiaceae) and synthesised Ag nanoparticles (NPs) using aqueous leaf extract against the adult cattle tick Haemaphysalis bispinosa Neumann (Acarina: Ixodidae) and the haematophagous fly Hippobosca maculata Leach (Diptera: Hippoboscidae). Synthesised Ag NPs were characterised with ultraviolet-vis (UV-vis) spectrum, scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FTIR) support the biosynthesis of Ag NPs. Parasites were exposed to varying concentrations of plant extracts and synthesised silver NPs for 24 h. All extracts showed the maximum toxic effect on parasites; however, the highest mortality was found in the hexane, chloroform, ethyl acetate, acetone, methanol and aqueous leaf extracts of E. prostrata and synthesised Ag NPs against the adult of H. bispinosa (LC(50)=45.24, 40.07, 21.91, 25.32, 19.30, 10.16 and 2.30 ppm; LC(90)=86.95, 88.66, 70.92, 83.22, 48.28, 70.27 and 8.28 ppm) and against H. maculata (LC(50)=39.37, 41.98, 19.92, 27. 93, 21.97, 9.79 and 2.55 ppm; LC(90)=89.44, 98.52, 76.59, 90.18, 55.07, 54.35 and 9.03 ppm), respectively. Mortality of 100% was found in synthesised Ag NPs at a concentration of 10 mg l(-1). UV-vis spectrograph of the colloidal solution of Ag NPs has been recorded as a function of time. The absorption spectrum of E. prostrata leaf extracts at different wavelengths ranging from 300 to 600 nm revealed a peak at 420 nm after 6 h. The FTIR spectra of Ag NPs exhibited prominent peaks at 3431; 1616; 1381; 1045; 818; 509; and 420 cm(-1). SEM analyses of the synthesised Ag NPs were rod shaped and measured 25-80 nm with an average size of 52.4 nm. The chemical composition of aqueous leaf extract was analysed by gas chromatography-mass spectrometry (GC-MS). The major chemical constituent was identified as 2-phenylethanol. These results suggest that the leaf methanol, aqueous extracts of E. prostrata and green synthesis of Ag NPs have the potential to be used as an ideal eco-friendly approach for the control of H. bispinosa and H. maculata. In addition, toxicity tests were conducted to analyse the toxicological effects of particle size on Daphnia magna and Ceriodaphnia dubia, and the animal model test was evaluated against Bos indicus for 24-h treatment. No toxicity on daphnids and no adverse effects were noted on animals after exposure to solvent extracts and synthesised Ag NPs.  相似文献   

13.
Ichthyophthirius multifiliis is a holotrichous protozoan that invades the gills and skin surfaces of fish and can cause morbidity and high mortality in most species of freshwater fish worldwide. The present study was undertaken to investigate the antiparasitic activity of crude extracts and pure compounds from the leaves of Macleaya microcarpa. The chloroform extract showed a promising antiparasitic activity against I. multifiliis. Based on these finding, the chloroform extract was fractionated on silica gel column chromatography in a bioactivity-guided isolation affording two compounds showing potent activity. The structures of the two compounds were elucidated as dihydrosanguinarine and dihydrochelerythrine by hydrogen and carbon-13 nuclear magnetic resonance spectrum and electron ionization mass spectrometry. The in vivo tests revealed that dihydrosanguinarine and dihydrochelerythrine were effective against I. multifiliis with median effective concentration (EC(50)) values of 5.18 and 9.43 mg/l, respectively. The acute toxicities (LC(50)) of dihydrosanguinarine and dihydrochelerythrine for richadsin were 13.3 and 18.2mg/l, respectively. The overall results provided important information for the potential application of dihydrosanguinarine and dihydrochelerythrine in the therapy of serious infection caused by I. multifiliis.  相似文献   

14.
The use of phytogenic bioactive compounds to control poultry helminthes is increasing in different production systems. In vitro and in vivo anthelmintic activity of citrus peels against Ascaridia galli was investigated. Ethanolic extracts of three citrus peels species were suspended in 0.5% dimethyl sulfoxide (DMSO) to form an experimental composition (EC). EC was mainly composed of Limonene (96%), followed by β-Pinene (1.5%), α-Pinene (0.5%), and Sabinene (0.3%). For in vitro investigation, adult A. galli worms (n=225) were collected from naturally infected chickens and distributed to 3 equal groups. Groups 1, 2, and 3 were exposed to Fenbendazole (0.5mg/ml), EC (50mg/ml), and 0.5% DMSO, respectively. For in vivo investigation, 200 Lohmann Selected Leghorns chicks were infected at 1-day old with 250 embryonated A. galli eggs. At 6 weeks of age, 150 A. galli infected birds were randomly allocated into 5 equal groups. Groups 1, 2, and 3 were treated with 300, 600, and 1200 mg EC kg(-1) body weight, respectively. Group 4 was treated with Fenbendazole (50 mg kg(-1)). Group 5 was left as control. Birds were euthanized 2-weeks post-treatment, and all worms were collected from their intestines. EC possessed significant (P<0.001) in vitro anthelmintic properties on live worms. No significant (P>0.05) difference was quantified between number of motile worms exposed either to EC or Fenbendazole 7h post-exposure. A significant (P<0.0001) reduction in fecal egg count was observed 14 days post-treatment with 1200 mg kg(-1) EC. No significant differences were observed in worm burden of the 300 mg EC-treated group compared to the controls. In contrast, the 600 and 1200 mg EC-treated groups showed significant (P<0.0001) reduction in worm burden. Fenbendazole was the most effective in reducing A. galli burden (Efficacy=97%) followed by 1200 mg EC kg(-1) (68%), 600 mg EC kg(-1) (66%), and 300 mg EC kg(-1) (5%). It is concluded that citrus peels extracts have potential anthelmintic properties against A. galli.  相似文献   

15.
Leaves of Palicourea marcgravii were extracted successively with hexane, ethyl acetate and ethanol in order to evaluate their acaricidal activity on larvae and adult stages of the cattle tick Rhipicephalus (Boophilus) microplus. The ethyl acetate extract showed the highest bioactivity of the tested extracts, which contained 0.12% monofluoroacetic acid. On engorged female, the ethyl acetate extract showed a lethal concentration 50% - LC(50)=30.08 mg ml(-1), inhibitory concentration 50% - IC(50)=5.79 mg ml(-1) and lethal time 50% - LT(50)=4.72 days; 100% reproduction was controlled at concentrations of 50 mg ml(-1) and on larvae the ethyl acetate extract showed a LC(50)=2.46 mg ml(-1). No alkaloids were detected in any of the extracts. This is the first report on the acaricidal activity of P. marcgravii extracts against R. microplus as well as the acaricidal properties of a plant species containing monofluoroacetic acid.  相似文献   

16.
The toxic effects of the extracts of Allium sativum (Garlic) were evaluated against adults of Hyalomma marginatum rufipes and Rhipicephalus pulchellus using three types (Types A, B and C) of contact toxicity bioassays. A. sativum bulbs were extracted with acetone, ethanol and dichloromethane (DCM) solvents. Among these three solvents, it is the DCM extract of A. sativum that appears to have anti-tick activity. In the Type A contact toxicity bioassay, DCM extracts of A. sativum demonstrated a high acaricidal bioactivity against H. m. rufipes with 100% of ticks killed in less than an hour, and toxicity persisted to the second day. A weak acaricidal activity of aqueous extracts of A. sativum was observed in the Type B contact toxicity bioassay. In the Type C contact toxicity bioassay, a concentration of 24% w/v of DCM extracts of garlic in sunflower oil (Helianthus annuus) had killed 100% of H. m. rufipes (LC50 = 5.9% w/v) and R. pulchellus (LC50 = 10.3% w/v) by 24 hours post-treatment of ticks. The results obtained from this study suggest that DCM extract of A. sativum is a potential source of novel acaricidal agents.  相似文献   

17.
采用室内生测法,研究了苍耳3种溶剂(丙酮、乙醇、氯仿)提取物对萝卜蚜和粘虫的作用方式及苍耳氯仿提取物对两种试虫的3种解毒酶活性的影响。结果表明,苍耳氯仿提取物对萝卜蚜有很强的忌避作用,当浓度为0.05 g/mL,处理4 h,忌避率达94.25%,48 h忌避率为84.53%;其次是触杀作用,校正死亡率最高为67.24%,LC50为0.7420 g/mL;内吸作用极弱。对粘虫主要表现为拒食和生长发育抑制作用,拒食校正死亡率最高达98.27%,AFC50为0.1985 g/mL;72 h体重增长率为-5.85%,与对照差异极显著;胃毒和触杀毒力较弱,LC50分别为0.8997和1.3070 g/mL。苍耳氯仿提取物对萝卜蚜和粘虫的乙酰胆碱酯酶(AchE)有抑制作用,处理萝卜蚜24 h及处理粘虫4 h时,乙酰胆碱酯酶(AchE)抑制率最高,分别为37.55%和25.65%;对谷胱甘肽转移酶(GSTs)和多功能氧化酶(MFO)活力影响不明显。  相似文献   

18.
何全磊  苗芳  李春玲 《草业学报》2012,21(5):285-290
通过毛细辛不同溶剂提取物体外抗氧化活性研究,为进一步开发毛细辛的药用价值提供参考。用50%的乙醇回流提取毛细辛的粉末,减压浓缩过滤得到乙醇浸膏,加蒸馏水制成悬浮液,依次用等体积的石油醚,乙酸乙酯,正丁醇萃取,得到石油醚,乙酸乙酯,正丁醇和水提物。以2,6-二叔丁基对甲酚(BHT)为对照,分别采用DPPH法、Fenton法、NBT还原法和Fe2+螯合法测定4种提取物的抗氧化活性。结果表明,毛细辛4种溶剂提取物均有不同程度的抗氧化活性,且活性与浓度成正相关。毛细辛乙酸乙酯提取物的1,2-二苯基-2-苦苯肼自由基(DPPH·)的清除活性(IC50值0.376 mg/mL),超氧阴离子自由基(O2-·)的清除活性(IC50值0.297 mg/mL)均最强。正丁醇提取物的羟基自由基(·OH)清除活性(IC50值0.776 mg/mL)为最强,水提物的金属离子螯合活性(IC50值0.026 mg/mL)为最强,远超过对照BHT(0.373 mg/mL)。实验表明,毛细辛乙酸乙酯提取物,正丁醇提取物和水提物均有较强的自由基清除活性,可作为新的自由基清除剂;水提物可以作为新的金属离子螯合剂。  相似文献   

19.
目的:探讨藏兽药蓝花侧金盏对兔螨的抑杀作用。方法:应用体外培养杀螨实验,比较了蓝花侧金盏水提取物、甲醇提取物、乙酸乙酯提取物及石油醚提取物的杀螨活性,并对活性较强的提取物的毒力和治疗兔螨病效果进行了评价。结果:4种提取物中,乙酸乙酯提取物具有较强的体外杀螨活性,高剂量(500 mg/mL)在体外培养6 h内全部杀死螨虫,4种浓度(500、250、125和62.5 mg/mL)的半数致死时间分别为0.743、2.73、5.919和22.536 h,并且其能有效治疗兔螨病,总有效率为90%。结论:蓝花侧金盏乙酸乙酯提取物具有良好的杀兔螨活性。  相似文献   

20.
The molluscicidal activity of seed and lyophilized latex powder of Carica papaya and seed powder of Areca catechu against the vector snail Lymnaea acuminata was studied. The toxicity of these plant products was time and dose dependent. The toxicity of C. papaya lyophilized latex powder (LC(50) at 96 h: 8.38 mg/l) was more pronounced than that of A. catechu seed powder (LC(50) at 96 h: 12.32 mg/l) and C. papaya seed powder (LC(50) at 96 h: 61.56 mg/l). Ethanolic extracts of C. papaya seed and A. catechu seed were more toxic than their other extracts. The ethanolic extract of A. catechu seed (LC(50) at 24h: 17.21 mg/l) was more effective than the ethanolic extract of C. papaya seed (LC(50) at 24h: 53.38 mg/l). The LC(50) of column-purified fraction of A. catechu seed at 96 h was 3.99 mg/l, whereas that of C. papaya seed was 7.06 mg/l. C. papaya and A. catechu may be used as potent molluscicides since the concentrations used to kill the snails were not toxic for the fish Colisa fasciatus which shares the same habitat with the snail L. acuminata.  相似文献   

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