Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 36
Filtrar
1.
Environ Res ; 260: 119618, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39009211

RESUMO

Lignites are widely available and cost-effective in many countries. Sustainable methods for their utilization drive innovation, potentially advancing environmental sustainability and resource efficiency. In the present study, Fe3O4 (∼25.1 nm) supported on KOH-activated lignite (A-L) displayed 8 times higher phosphate removal than pristine A-L (67.6 mg/g vs. 8.5 mg/g at pH 5, 50 mg of absorbent in 25 mL of 1500 ppm [phosphate]), owing to its abundant Fe3O4 (10 wt% of Fe) nanoparticle content. The removal occurred within ∼2 h, following a pseudo-second-order kinetic model. Across pH levels ranging from 5.0 to 9.0, Fe3O4-A-L's phosphate removal occurs via both chemisorption and precipitation, as evident by kinetic, pH, and XPS analyses. The phosphate adsorption fits better with the Freundlich isotherm. The combined benefits of facile recovery, rapid phosphate uptake, straightforward regeneration, and attractive post-adsorption benefits (e.g., possibly use as a Fe, P-rich fertilizer) make magnetic Fe3O4-A-L a promising candidate for real-world applications. Artificial Neural Network (ANN) modeling indicates an excellent accuracy (R2 = 0.99) in predicting the amount of phosphate removed by Fe3O4-A-L. Sensitivity analysis revealed both temperature and initial concentration as the most influencing factors. Leveraging lignite in environmentally friendly applications not only addresses immediate challenges but also aligns with sustainability goals. The study clearly articulates the potential benefits of utilizing lignite for sustainable phosphate removal and recovery, offering avenues for mitigating environmental concerns while utilizing resources efficiently.

2.
Antimicrob Agents Chemother ; 59(8): 4782-99, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26033724

RESUMO

The aim of the present study was to synthesize silver (Ag) and titanium dioxide (TiO2) nanoparticles (NPs) using green synthesis from aqueous leaf extract of Euphorbia prostrata as antileishmanial agents and to explore the underlying molecular mechanism of induced cell death. In vitro antileishmanial activity of synthesized NPs was tested against promastigotes of Leishmania donovani by alamarBlue and propidium iodide uptake assays. Antileishmanial activity of synthesized NPs on intracellular amastigotes was assessed by Giemsa staining. The leishmanicidal effect of synthesized Ag NPs was further confirmed by DNA fragmentation assay and by cell cycle progression and transmission electron microscopy (TEM) of the treated parasites. TEM analysis of the synthesized Ag NPs showed a spherical shape with an average size of 12.82 ± 2.50 nm, and in comparison to synthesized TiO2 NPs, synthesized Ag NPs were found to be most active against Leishmania parasites after 24 h exposure, with 50% inhibitory concentrations (IC50) of 14.94 µg/ml and 3.89 µg/ml in promastigotes and intracellular amastigotes, respectively. A significant increase in G0/G1 phase of the cell cycle with a subsequent decrease in S (synthesis) and G2/M phases compared to controls was observed. The growth-inhibitory effect of synthesized Ag NPs was attributed to increased length of S phase. A decreased reactive oxygen species level was also observed, which could be responsible for the caspase-independent shift from apoptosis (G0/G1 arrest) to massive necrosis. High-molecular-weight DNA fragmentation as a positive consequence of necrotic cell death was also visualized. We also report that the unique trypanothione/trypanothione reductase (TR) system of Leishmania cells was significantly inhibited by synthesized Ag NPs. The green-synthesized Ag NPs may provide promising leads for the development of cost-effective and safer alternative treatment against visceral leishmaniasis.


Assuntos
Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Euphorbia/química , Leishmania donovani/efeitos dos fármacos , Nanopartículas Metálicas/administração & dosagem , Prata/farmacologia , Titânio/farmacologia , Antiprotozoários/química , Antiprotozoários/farmacologia , Caspases/metabolismo , Fase G1/efeitos dos fármacos , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/metabolismo , Nanopartículas Metálicas/química , Necrose/tratamento farmacológico , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Prata/química , Titânio/química
3.
Malar J ; 14: 65, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25879738

RESUMO

BACKGROUND: Development of resistance against the frontline anti-malarial drugs has created an alarming situation, which requires intensive drug discovery to develop new, more effective, affordable and accessible anti-malarial agents. METHODS: Inspired by their ethnobotanical reputation for being effective against febrile diseases, antiplasmodial potential of ethyl acetate extracts (EAE) and methanol extracts (ME) of 17 medicinal plants collected from the Eastern Ghats of South India and Buchpora, North India were explored against Plasmodium falciparum in vitro using the SYBR Green assay. The results were validated both by confirmation that the fall in fluorescence signal was not due to quenching effects mediated by phytochemical extracts and by Giemsa-stained microscopy. RESULTS: Using EAE or ME, promising antiplasmodial activity (IC50 Pf3D7 ≤ 20 µg/ml), was seen in Aerva lanata (Whole aerial parts-EAE), Anisomeles malabarica (Leaf-EAE), Anogeissus latifolia (bark-EAE), Cassia alata (leaves-EAE), Glycyrrhiza glabra (root-EAE), Juglans regia (seed-ME), Psidium guajava (leaf-ME and EAE) and Solanum xanthocarpum (Whole aerial parts-EAE). EAEs from leaves of Couroupita guianensis, Euphorbia hirta, Pergularia daemia, Tinospora cordifolia and Tridax procumbens as also ME from Ricinus communis (leaf and seed) showed good antiplasmodial activity (Pf 3D7 IC50 21 - 40 µg/ml). Moderate activity (Pf 3D7 IC50: 40-60 µg/mL) was shown by the leaf EAEs of Cardiospermum halicacabum, Indigofera tinctoria and Ricinus communis while the remaining extracts showed marginal (Pf 3D7 IC50 60 to >100 µg/ml) activities. The promising extracts showed good resistance indices (0.41 - 1.4) against the chloroquine resistant INDO strain of P. falciparum and good selectivity indices (3 to > 22.2) when tested against the HeLa cell line. CONCLUSION: These results provide validity to the traditional medicinal usage of some of these plants and further make a case for activity-guided purification of new pharmacophores against malaria.


Assuntos
Antimaláricos/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Plasmodium falciparum/efeitos dos fármacos , Antimaláricos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Eritrócitos/parasitologia , Células HeLa , Humanos , Índia , Extratos Vegetais/toxicidade
4.
Parasitol Res ; 113(2): 469-79, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24265057

RESUMO

Titanium dioxide nanoparticles (TiO2 NPs) are widely used in paints, printing ink, rubber, paper, cosmetics, sunscreens, car materials, cleaning air products, industrial photocatalytic processes, and decomposing organic matters in wastewater due to their unique physical, chemical, and biological properties. The present study was conducted to assess the antiparasitic efficacies of synthesized TiO2 NPs utilizing leaf aqueous extract of Solanum trilobatum against the adult head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae); larvae of cattle tick Hyalomma anatolicum (a.) anatolicum Koch (Acari: Ixodidae), and fourth instar larvae of malaria vector Anopheles subpictus Grassi (Diptera: Culicidae). The green synthesized TiO2 NPs were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy analysis (EDX), and Atomic force microscopy (AFM). XRD analysis of synthesized TiO2 NPs revealed that the particles were in the form of nanocrystals as evidenced by the major peaks at 2θ values of 27.52°, 36.21°, and 54.43° identified as 110, 101, and 211 reflections, respectively. FTIR spectra exhibited a prominent peak at 3,466 cm(-1) and showed OH stretching due to the alcoholic group, and the OH group may act as a capping agent. SEM images displayed NPs that were spherical, oval in shape, individual, and some in aggregates with an average size of 70 nm. Characterization of the synthesized TiO2 NPs using AFM offered a three-dimensional visualization and uneven surface morphology. The pediculocidal and acaricidal activities of synthesized TiO2 NPs showed the percent mortality of 31, 42, 63, 82, 100; 36, 44, 67, 89, and 100 at 2, 4, 6, 8, and 10 mg/L, respectively, against P. h. capitis and H. a. anatolicum. The average larval percent mortality of synthesized TiO2 NPs was 38, 47, 66, 79, and 100 at 1, 2, 3, 4, and 5 mg/L, respectively, against A. subpictus. The maximum activity was observed in the aqueous leaf extract of S. trilobatum, TiO(OH)2 solutions (bulk), and synthesized TiO2 NPs with LC50 values of 35.14, 25.85, and 4.34 mg/L; 47.15, 29.78, and 4.11 mg/L; and 28.80, 24.01, and 1.94 mg/L, and r (2) values of 0.982, 0.991, and 0.992; 0.947, 0.987, and 0.997; and 0.965, 0.998 and 0.985, respectively, against P. h. capitis, H. a. anatolicum, and A. subpictus. This study provides the first report on the pediculocidal, acaricidal, and larvicidal activity of synthesized TiO2 NPs. This is an ideal eco-friendly, novel, low-cost, and simple approach to satisfy the requirement of large-scale industrial production bearing the advantage for the control of P. h. capitis, H. a. anatolicum, and A. subpictus.


Assuntos
Anopheles/efeitos dos fármacos , Ixodidae/efeitos dos fármacos , Nanopartículas Metálicas , Pediculus/efeitos dos fármacos , Extratos Vegetais/metabolismo , Solanum/química , Titânio/farmacologia , Acaricidas/farmacologia , Animais , Bovinos , Humanos , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Testes de Sensibilidade Parasitária , Folhas de Planta/química , Espectrometria por Raios X , Difração de Raios X
5.
Parasitol Res ; 113(5): 1657-72, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24638906

RESUMO

Malaria is an overwhelming impact in the poorest countries in the world due to their prevalence, virulence and drug resistance ability. Currently, there is inadequate armoury of drugs for the treatment of malaria. This underscores the continuing need for the discovery and development of new effective and safe antimalarial drugs. To evaluate the in vitro and in vivo antimalarial activity of the leaf ethyl acetate extract of Murraya koenigii, bioassay-guided chromatographic fractionation was employed for the isolation and purification of antimalarial compounds. The in vitro antimalarial activity was assayed by the erythrocytic stages of chloroquine-sensitive strain of Plasmodium falciparum (3D7) in culture using the fluorescence-based SYBR Green I assay. The in vivo assay was done by administering mice infected with Plasmodium berghei (NK65) four consecutive daily doses of the extracts through oral route following Peter's 4-day curative standard test. The percentage suppression of parasitaemia was calculated for each dose level by comparing the parasitaemia in untreated control with those of treated mice. Cytotoxicity was determined against HeLa cells using MTT assay. Histopathology was studied in kidney, liver and spleen of isolated compound-treated Swiss albino mice. The leaf crude ethyl acetate extract of M. koenigii showed good in vitro antiplasmodial activity against P. falciparum. The in vivo test of the leaf crude ethyl acetate extract (600 mg/kg) showed reduced malaria parasitaemia by 86.6% against P. berghei in mice. Bioassay-guided fractionation of the leaf ethyl acetate extract of M. koenigii led to the isolation of two purified fractions C3B2 (2.84 g) and C3B4 (1.97 g). The purified fractions C3B2 and C3B4 were found to be active with IC50 values of 10.5 ± 0.8 and 8.25 ± 0.2 µg/mL against P. falciparum, and in vivo activity significantly reduced parasitaemia by 82.6 and 88.2% at 100 mg/kg/body weight on day 4 against P. berghei, respectively. The isolated fractions C3B2 and C3B4 were monitored by thin-layer chromatography until a single spot was obtained with R f values of 0.36 and 0.52, respectively. The pure compounds obtained in the present investigation were subjected to UV-visible spectroscopy, Fourier transformer infrared spectroscopy, 1D and 2D (1)H-Nuclear magnetic resonance (NMR), (13)C NMR, DEPT, COSY and Mass spectral analysis. Based on the spectral analysis, it is concluded that the isolated compounds were myristic acid (C3B2) and ß-caryophyllene (C3B4). The cytotoxic effect of myristic acid and ß-caryophyllene showed the TC50 values of >100 and 80.5 µg/mL, respectively against HeLa cell line. The histopathology study showed that protection against nephrotoxicity of kidney, hepatic damage of liver and splenocytes protection in spleen was achieved with the highest dose tested at 100 mg/kg/body weight. The present study provides evidence of antiplasmodial compounds from M. koenigii and is reported for the first time.


Assuntos
Antimaláricos/farmacologia , Murraya/química , Extratos Vegetais/farmacologia , Plasmodium berghei/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Animais , Antimaláricos/química , Feminino , Células HeLa , Humanos , Malária/tratamento farmacológico , Masculino , Camundongos , Ácido Mirístico/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química , Sesquiterpenos Policíclicos , Sesquiterpenos/isolamento & purificação
6.
Exp Parasitol ; 134(1): 26-32, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23399920

RESUMO

Malaria caused by the protozoan parasite Plasmodium falciparum, is a major health problem of the developing world. In the present study medicinal plants from Eastern Ghats of South India have been extracted with ethyl acetate and assayed for growth inhibition of asexual erythrocytic stages of chloroquine (CQ)-sensitive (3D7) and (CQ)-resistant (INDO) strains of P. falciparum in culture using the fluorescence-based SYBR Green I assay. Studied extracts showed a spectrum of antiplasmodial activities ranging from (a) very good (IC(50)<10-10 µg/mL: Cyperus rotundus and Zingiber officinale); (b) good (IC(50), >10-15 µg/mL: Ficus religiosa and Murraya koenigii); (c) moderate (IC(50)>15-25 µg/mL: Ficus benghalensis); (d) poor activity (IC(50)>25-60 µg/mL) and (e) inactive (IC(50)>60 µg/mL). Resistance indices ranging from 0.78 to 1.28 suggest that some of these extracts had equal promise against the CQ resistant INDO strain of P. falciparum. Cytotoxicity assessment of the extracts against HeLa cell line using MTT assay revealed that the selectivity indices in the range of 3-15 suggesting a good margin of safety.


Assuntos
Extratos Vegetais/farmacologia , Plantas Medicinais/química , Plasmodium falciparum/efeitos dos fármacos , Cyperus/química , Resistência a Medicamentos , Ficus/química , Zingiber officinale/química , Células HeLa/efeitos dos fármacos , Humanos , Índia , Concentração Inibidora 50 , Murraya/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade
7.
Parasitol Res ; 112(1): 215-26, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22009268

RESUMO

The aim of the present study was to assess the larvicidal property of marine actinobacterial compound 5-(2,4-dimethylbenzyl) pyrrolidin-2-one (DMBPO) extracted and isolated from Streptomyces VITSVK5 sp. tested against the larvae of Rhipicephalus (Boophilus) microplus Canestrini (Acari: Ixodidae), Anopheles stephensi Liston, and Culex tritaeniorhynchus Giles (Diptera: Culicidae). The isolate bacteria was taxonomically characterized, identified, and designated as Streptomyces VITSVK5 sp. The crude extract was loaded on silica gel column and eluted with chloroform:methanol. The isolated pure compound was analyzed by thin layer chromatography using chloroform and methanol as the solvent system and confirmed by high-performance liquid chromatography. The structure of the purified compound was established from infrared, ultraviolet, (1)H-nuclear magnetic resonance (NMR), (13)C-NMR, and mass spectral data. The chemical shift assignments obtained for the aliphatic compound from (1)H-NMR corresponding to the molecular formula C(13)H(17)NO. Bioassay-guided fractionation led to the isolation of compound which was identified as DMBPO. In the present study, Streptomyces VITSVK5 sp. crude extract and different fractions were tested against the larvae of parasites at the concentration of 1,000 ppm. Those fractions showing 100% mortality in 24 h alone was selected for further column chromatographic separation. The purified compound, C(13)H(17)NO, was tested in the concentrations of 500, 250, 125, 62.5, and 31.25 ppm and observed the percent larval mortality of 100, 70, 64, 40, and 28 against R. microplus; 100, 79, 63, 36, and 22 against A. stephensi; and 100, 84, 67, 42, and 27 against C. tritaeniorhynchus, respectively. The crude extract showed parasitic effects after 24 h of exposure at 1,000 ppm, and parasite mortality was observed against the larvae of R. microplus (LC(50) = 210.39 ppm, r (2) = 0.873); A. stephensi (LC(50) = 169.38 ppm, r (2) = 0.840); and C. tritaeniorhynchus (LC(50) = 198.75 ppm, r (2) = 0.887). The maximum efficacy was observed in purified marine actinobacterial compound DMBPO with LC(50) and r (2) values against the larvae of R. microplus (84.31 ppm, 0.889); A. stephensi (88.97 ppm, 0.817), and C. tritaeniorhynchus (74.95 ppm, 0.781), respectively. The control (distilled water) showed nil mortality in the concurrent assay.


Assuntos
Anopheles/efeitos dos fármacos , Culex/efeitos dos fármacos , Inseticidas/farmacologia , Pirrolidinonas/farmacologia , Rhipicephalus/efeitos dos fármacos , Streptomyces/química , Animais , Cromatografia em Camada Fina , Inseticidas/química , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Estrutura Molecular , Pirrolidinonas/química , Pirrolidinonas/isolamento & purificação , Análise Espectral , Streptomyces/classificação , Streptomyces/isolamento & purificação , Análise de Sobrevida
8.
Chemosphere ; 313: 137533, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36528163

RESUMO

In this present study, silver (Ag) and titanium dioxide (TiO2) nanoparticles were successfully deposited on coconut shell-derived activated carbon (CSAC), to synthesize a novel nanocomposite (CSAC@AgNPs@TiO2NPs) for the adsorption of Methylene Blue (MB) dye from aqueous solution. The fabricated CSAC@AgNPs@TiO2NPs nanocomposite was analyzed by Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), Transmission Electron Microscope (TEM) equipped with Energy Dispersive X-ray spectroscopy (EDS) detector, X-ray Photoelectron Spectroscope (XPS), and Brunauer-Emmett-Teller (BET). The successful deposition of AgNPs and TiO2NPs on CSAC surface was revealed by the TEM/EDX, SEM, and XPS analysis. The mesopore structure of CSAC@AgNPs@TiO2NPs has a BET surface area of 301 m2/g. The batch adsorption studies were conducted and the influence of different parameters, i.e., adsorbent dose, adsorption time, initial dye concentration, pH and temperature were investigated. The nonlinear isotherm and kinetic modelling demonstrated that adsorption data were best fitted by Sips isotherm and pseudo-second-order models, respectively. The maximum adsorption capacity of MB onto CSAC@AgNPs@TiO2NPs by the Sips model was 184 mg/g. Thermodynamic results revealed that the adsorption was endothermic, spontaneous and physical in nature. CSAC@AgNPs@TiO2NPs revealed that MB absorption by CSAC@AgNPs@TiO2NPs was spontaneous and endothermic. The uptake capacity of MB was influenced significantly by the presence of competing ions including, NO3-, HCO3, Ca2+, and Na+. Repeated tests indicated that the CSAC@AgNPs@TiO2NPs can be regenerated and reused six times before being discarded. The primary separation mechanism between MB dye and CSAC@AgNPs@TiO2NPs was the electrostatic interaction. Thus, CSAC@AgNPs@TiO2NPs was an outstanding material, which displayed good applicability in real water with ≥ 97% removal of MB dye.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Azul de Metileno/química , Carvão Vegetal/química , Água , Poluentes Químicos da Água/análise , Nanopartículas/química
9.
Exp Parasitol ; 132(2): 180-4, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22771864

RESUMO

Infections due to protozoa of the genus Leishmania are a major worldwide health problem, with high endemicity in developing countries. The aim of this study was to evaluate the in vitro antileishmanial activity of the acetone and methanol leaf extracts of Anisomeles malabarica, flower of Gloriosa superba, leaf of Ocimum basilicum, leaf and seed of Ricinus communis against promastigotes form of Leishmania donovani. Antiparasitic evaluations of different plant crude extracts were performed on 96 well plates at 37°C for 24-48 h. Out of the 10 experimental plant extracts tested, the leaf methanol extracts of A. malabarica, and R. communis showed good antileishmanial activity (IC(50)=126±19.70 and 184±39.33 µg/mL), respectively against promastigotes. Effective antileishmanial activity was observed making these plants as good candidates for isolation of antiprotozoal compounds which could serve as new lead structures for drug development.


Assuntos
Leishmania donovani/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Relação Dose-Resposta a Droga , Flores/química , Índia , Lamiaceae/química , Liliaceae/química , Ocimum basilicum/química , Folhas de Planta/química , Ricinus/química , Sementes/química
10.
Exp Parasitol ; 132(2): 156-65, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22750410

RESUMO

The present study was to determine the efficacies of anti-parasitic activities of synthesized silver nanoparticles (Ag NPs) using stem aqueous extract of Cissus quadrangularis against the adult of hematophagous fly, Hippobosca maculata (Diptera: Hippoboscidae), and the larvae of cattle tick, Rhipicephalus (Boophilus) microplus (Acari: Ixodidae). Contact toxicity method was followed to determine the potential of parasitic activity. Twelve milliliters of stem aqueous extract of C. quadrangularis was treated with 88 ml of 1mM silver nitrate (AgNO(3)) solution at room temperature for 30 min and the resulting solution was yellow-brown color indicating the formation extracellular synthesis of Ag NPs. The synthesized Ag NPs were characterized with UV-visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscope (FESEM) and energy dispersive X-ray (EDX) spectroscopy. The synthesized Ag NPs were recorded by UV-visible spectrum at 420 nm and XRD patterns showed the nanoparticles crystalline in nature. FTIR analysis confirmed that the bioreduction of Ag((+)) ions to Ag NPs were due to the reduction by capping material of plant extract. FESEM image of Ag NPs showed spherical and oval in shape. By using the Bragg's Law and Scherrer's constant, the average mean size of synthesized Ag NPs was 42.46 nm. The spot EDX analysis showed the complete chemical composition of the synthesized Ag NPs. The mortality obtained by the synthesized Ag NPs from the C. quadrangularis was more effective than the aqueous extract of C. quadrangularis and AgNO(3) solution (1 mM). The adulticidal activity was observed in the aqueous extract, AgNO(3) solution and synthesized Ag NPs against the adult of H. maculata with LC(50) values of 37.08, 40.35 and 6.30 mg/L; LC(90) values of 175.46, 192.17 and 18.14 mg/L and r(2) values of 0.970, 0.992 and 0.969, respectively. The maximum efficacy showed in the aqueous extract, AgNO(3) solution and synthesized Ag NPs against the larvae of R. (B.) microplus with LC(50) values of 50.00, 21.72 and 7.61 mg/L; LC(90) values of 205.12, 82.99 and 22.68 mg/L and r(2) values of 0.968, 0.945 and 0.994, respectively. The present study is the first report on antiparasitic activity of the experimental plant extract and synthesized Ag NPs. This is an ideal eco-friendly and inexpensive approach for the control of H. maculata and R. (B.) microplus.


Assuntos
Cissus/química , Dípteros/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rhipicephalus/efeitos dos fármacos , Animais , Bioensaio , Bovinos , Doenças dos Bovinos/tratamento farmacológico , Doenças dos Bovinos/parasitologia , Ectoparasitoses/tratamento farmacológico , Ectoparasitoses/veterinária , Feminino , Larva/efeitos dos fármacos , Dose Letal Mediana , Nanopartículas Metálicas/química , Microscopia Eletrônica de Varredura/métodos , Extratos Vegetais/uso terapêutico , Caules de Planta/química , Prata , Nitrato de Prata , Soluções , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Infestações por Carrapato/tratamento farmacológico , Infestações por Carrapato/veterinária , Difração de Raios X
11.
Parasitol Res ; 111(4): 1629-35, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21842382

RESUMO

The purpose of this study is to determine the efficacies of hexane, chloroform, ethyl acetate, acetone, and methanol leaf extracts of Euphorbia hirta L., Psidium guajava L., Ricinus communis L., Solanum trilobatum L., and Tridax procumbens L. against sheep fluke Paramphistomum cervi (Digenea: Paramphistomatidae). All plant extracts showed moderate effects after 24 h of exposure; however, the highest parasite mortality was found in the methanol extract of R. communis. In the present study, bioassay-guided fractionation of methanol extract of R. communis led to the separation and identification of epicatechin as a potential new compound (LC(50) = 31.2; LC(90) = 105.0 ppm) against P. cervi. The structures were established from infrared, ultraviolet, (1)H-nuclear magnetic resonance (NMR), (13)C-NMR, and mass spectral data which confirmed the identification of the compound epicatechin from R. communis. Results of this study showed that the methanol extract of R. communis may be considered as a potent source and epicatechin as a new natural parasitic agent.


Assuntos
Anti-Helmínticos/farmacologia , Catequina/farmacologia , Paramphistomatidae/efeitos dos fármacos , Extratos Vegetais/farmacologia , Ricinus/química , Animais , Anti-Helmínticos/isolamento & purificação , Catequina/química , Catequina/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Plantas Medicinais/química , Análise de Sobrevida
12.
Parasitol Res ; 111(6): 2439-48, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22033735

RESUMO

With a greater awareness of the hazards associated with the use of synthetic organic insecticides, there has been an urgent need to explore suitable alternative products for pest control. Musca domestica is ubiquitous insect that has the potential to spread a variety of pathogens to humans and livestock. They are mechanical carriers of more than hundred human and animal intestinal diseases and are responsible for protozoan, bacterial, helminthic, and viral infections. The present work aimed to investigate the feeding deterrent activity of synthesized silver nanoparticles (Ag NPs) using leaf aqueous extract of Manilkara zapota against M. domestica. The synthesized Ag NPs were recorded from UV-vis spectrum at 421 nm and scanning electron microscopy confirm the biosynthesis and characterization of Ag NPs with spherical and oval in shape and size of 70-140 nm. The FTIR analysis of the purified nanoparticles showed the presence of bands 1,079, 1,383, 1,627, 2,353, and 2,648 cm(-1), which were complete synthesis of AgNPs; the XRD pattern of AgNPs showed diffraction peaks at 2θ values of 38.06°, 44.37°, 64.51°, and 77.31° sets of lattice planes were observed (111), (200), (220), and (311) facts of silver, respectively. Adult flies were exposed to different concentrations of the aqueous extract of synthesized Ag NPs, 1 mM silver nitrate (AgNO(3)) solution and aqueous extract of M. zapota for 1, 2, and 3 h; however, AgNPs showed 72% mortality in 1 h, 89% mortality was found in 2 h, and 100% mortality was found in 3 h exposure at the concentration of 10 mg/mL and the leaf aqueous extract showed 32% mortality in 1 h, 48% mortality was found in 2 h, and 83% mortality was found in 3 h exposure at concentration of 50 mg/mL. The most efficient activity was observed in synthesized Ag NPs against M. domestica (LD(50) = 3.64 mg/mL; LD(90) = 7.74 mg/mL), the moderate activity reported in the aqueous extract of M. zapota (LD(50) = 28.35 mg/mL; LD(90) = 89.19 mg/mL) and nil activity were observed in AgNO(3) solution at 3 h exposure time at 10 mg/mL. Dimethyl 2, 2-dichlorovinyl phosphate (DDVP) was used as a positive control and showed the LD(50) value of 3.38 mL/L. These results suggest that the synthesized Ag NPs have the potential to be used as an ideal eco-friendly approach for the control of the adult of M. domestica. This method is considered as a new approach to control sanitary pest. Therefore, this study provides first report on the feeding deterrent activity of synthesized Ag NPs against housefly.


Assuntos
Moscas Domésticas/efeitos dos fármacos , Repelentes de Insetos/farmacologia , Manilkara/metabolismo , Nanopartículas , Prata/farmacologia , Animais , Repelentes de Insetos/metabolismo , Dose Letal Mediana , Microscopia Eletrônica de Varredura , Extratos Vegetais/metabolismo , Folhas de Planta/metabolismo , Prata/metabolismo , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise de Sobrevida
13.
Parasitol Res ; 111(2): 703-15, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21643655

RESUMO

The emergence and spread of Plasmodium falciparum with resistance to chloroquine (CQ), the safest and cheapest anti-malarial drug, coupled with the increasing cost of alternative drugs especially in developing countries have necessitated the urgent need to tap the potential of plants for novel anti-malarials. The present study investigates the anti-malarial activity of the methanolic extracts of 13 medicinal plants from the Malaiyur and Javadhu hills of South India against blood stage CQ-sensitive (3D7) and CQ-resistant (INDO) strains of P. falciparum in culture using the fluorescence-based SYBR Green I assay. Sorbitol-synchronized parasites were incubated under normal culture conditions at 2% hematocrit and 1% parasitemia in the absence or presence of increasing concentrations of plant extracts. CQ and artemisinin were used as positive controls, while 0.4% DMSO was used as the negative control. The cytotoxic effects of extracts on host cells were assessed by functional assay using HeLa cells cultured in RPMI containing 10% fetal bovine serum, 0.21% sodium bicarbonate and 50 µg/mL gentamycin (complete medium). Plant extracts (bark methanol extracts of Annona squamosa (IC(50), 30 µg/mL), leaf extracts of Ocimum gratissimum (IC(50), 32 µg/mL), Ocimum tenuiflorum (IC(50), 31 µg/mL), Solanum torvum (IC(50), 31 µg/mL) and Justicia procumbens (IC(50), 63 µg/mL), showed moderate activity. The leaf extracts of Aristolochia indica (IC(50), 10 µg/mL), Cassia auriculata (IC(50), 14 µg/mL), Chrysanthemum indicum (IC(50), 20 µg/mL) and Dolichos biflorus (IC(50), 20 µg/mL) showed promising activity and low activity was observed in the flower methanol extracts of A. indica , leaf methanol extract of Catharanthus roseus, and Gymnema sylvestre (IC(50), >100 µg/mL). These four extracts exhibited promising IC(50) (µg/mL) of 17, 24, 19 and 24 respectively also against the CQ resistant INDO strain of P. falciparum. The high TC(50) in mammalian cell cytotoxicity assay and the low IC(50) in anti-malarial P. falciparum assay indicates selectivity and good resistance indices in the range of 0.9-1.7 for leaf extracts of A. indica, C. auriculata, C. indicum and D. biflorus suggests that these may serve as anti-malarial agents even in their crude form. These results indicate a possible explanation of the traditional use of some of these medicinal plants against malaria or malaria-like conditions.


Assuntos
Antimaláricos/uso terapêutico , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Plasmodium falciparum/efeitos dos fármacos , Animais , Antimaláricos/química , Cloroquina/farmacologia , Resistência a Medicamentos , Células HeLa , Humanos , Índia , Componentes Aéreos da Planta/química , Extratos Vegetais/química
14.
Parasitol Res ; 111(2): 921-33, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21638210

RESUMO

The purpose of the present study was to investigate the acaricidal and larvicidal activity against the larvae of Haemaphysalis bispinosa Neumann (Acarina: Ixodidae) and larvae of hematophagous fly Hippobosca maculata Leach (Diptera: Hippoboscidae) and against the fourth-instar larvae of malaria vector, Anopheles stephensi Liston, Japanese encephalitis vector, Culex tritaeniorhynchus Giles (Diptera: Culicidae) of synthesized silver nanoparticles (AgNPs) utilizing aqueous leaf extract from Musa paradisiaca L. (Musaceae). The color of the extract changed to light brown within an hour, and later it changed to dark brown during the 30-min incubation period. AgNPs results were recorded from UV-vis spectrum at 426 nm; Fourier transform infrared (FTIR) analysis confirmed that the bioreduction of Ag(+) ions to silver nanoparticles are due to the reduction by capping material of plant extract, X-ray diffraction (XRD) patterns clearly illustrates that the nanoparticles formed in the present synthesis are crystalline in nature and scanning electron microscopy (SEM) support the biosynthesis and characterization of AgNPs with rod in shape and size of 60-150 nm. After reaction, the XRD pattern of AgNPs showed diffraction peaks at 2θ = 34.37°, 38.01°, 44.17°, 66.34° and 77.29° assigned to the (100), (111), (102), (110) and (120) planes, respectively, of a faced centre cubic (fcc) lattice of silver were obtained. For electron microscopic studies, a 25 µl sample was sputter-coated on copper stub, and the images of nanoparticles were studied using scanning electron microscopy. The spot EDX analysis showed the complete chemical composition of the synthesized AgNPs. The parasite larvae were exposed to varying concentrations of aqueous extract of M. paradisiaca and synthesized AgNPs for 24 h. In the present study, the percent mortality of aqueous extract of M. paradisiaca were 82, 71, 46, 29, 11 and 78, 66, 38, 31and 16 observed in the concentrations of 50, 40, 30, 20, 10 mg/l for 24 h against the larvae of H. bispinosa and Hip. maculata, respectively. The maximum efficacy was observed in the aqueous extract of M. paradisiaca against the H. bispinosa, Hip. maculata, and the larvae of A. stephensi, C. tritaeniorhynchus with LC(50) values of 28.96, 31.02, 26.32, and 20.10 mg/lm, respectively (r (2) = 0.990, 0.968, 0.974, and 0.979, respectively). The synthesized AgNPs of M. paradisiaca showed the LC(50) and r (2) values against H. bispinosa, (1.87 mg/l; 0.963), Hip. maculata (2.02 mg/l; 0.976), and larvae of A. stephensi (1.39; 0.900 mg/l), against C. tritaeniorhynchus (1.63 mg/l; 0.951), respectively. The χ (2) values were significant at p < 0.05 level.


Assuntos
Acaricidas/farmacologia , Insetos/efeitos dos fármacos , Ixodidae/efeitos dos fármacos , Nanopartículas Metálicas/química , Musa/metabolismo , Prata/farmacologia , Acaricidas/química , Animais , Frutas , Larva/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Prata/química
15.
Parasitol Res ; 111(4): 1833-40, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21861064

RESUMO

The aim of the present study was to investigate the adulticidal and larvicidal activity of dried leaf hexane, ethyl acetate, acetone, and methanol extracts of Nelumbo nucifera, Manilkara zapota, Ipomoea staphylina, and Acalypha indica against the adults of Haemaphysalis bispinosa (Acarina: Ixodidae), hematophagous fly Hippobosca maculata (Diptera: Hippoboscidae), and fourth instar larvae of malaria vector Anopheles subpictus (Diptera: Culicidae). Parasites were exposed to varying concentrations of plant extracts for 24 h. All extracts showed moderate parasitic effects; however, the percent parasitic mortality observed in the crude leaf hexane, ethyl acetate, acetone, and methanol extracts of N. nucifera and M. zapota against H. bispinosa were 80, 74, 72, and 100 and 100, 83, 74, and 91, respectively, and the activity for I. staphylina and A. indica against Hip. maculata were 100, 93, 87, and 66 and 78, 90, 87, and 100 at 2,000 ppm, respectively; the larvicidal activity for the same extracts of I. staphylina against A. subpictus were 76, 82, 84, and 100 at 100 ppm, respectively. The maximum efficacy was observed in the leaf methanol extract of N. nucifera, hexane extract of M. zapota and leaf hexane extract of I. staphylina, and methanol extract of A. indica against the adults of H. bispinosa and Hip. maculata with LC(50) and LC(90) values of 437.14 and 200.81, and 415.14 and 280.72 ppm, 1,927.57 and 703.52 ppm, and 1,647.70 and 829.39 ppm, respectively. The effective larvicidal activity was observed in leaf methanol extract of I. staphylina against A. subpictus with LC(50) and LC(90) values of 10.39 and 37.71 ppm, respectively. Therefore, this study provides the first report on the adulticidal and larvicidal activity of crude solvent extracts. This is an ideal eco-friendly approach for the control of H. bispinosa, Hip. maculata, and the medically important vector A. subpictus.


Assuntos
Dípteros/efeitos dos fármacos , Gleiquênias/química , Inseticidas/farmacologia , Ixodidae/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Análise de Sobrevida
16.
Parasitol Res ; 111(6): 2329-37, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21987105

RESUMO

The purpose of the present study was based on assessments of the antiparasitic activities of synthesized titanium dioxide nanoparticles (TiO(2) NPs) utilizing leaf aqueous extract of Catharanthus roseus against the adults of hematophagous fly, Hippobosca maculata Leach (Diptera: Hippoboscidae), and sheep-biting louse, Bovicola ovis Schrank (Phthiraptera: Trichodectidae). The synthesized TiO(2) NPs were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The formation of the TiO(2) NPs synthesized from the XRD spectrum compared with the standard confirmed spectrum of titanium particles formed in the present experiments were in the form of nanocrystals, as evidenced by the peaks at 2θ values of 27.43°, 36.03°, and 54.32°. The FTIR spectra of TiO(2) NPs exhibited prominent peaks at 714 (Ti-O-O bond), 1,076 (C-N stretch aliphatic amines), 1,172 (C-O stretching vibrations in alcoholic groups), 1,642 (N-H bend bond), and 3,426 (O-H stretching due to alcoholic group). SEM analysis of the synthesized TiO(2) NPs clearly showed the clustered and irregular shapes, mostly aggregated and having the size of 25-110 nm. By Bragg's law and Scherrer's constant, it is proved that the mean size of synthesized TiO(2) NPs was 65 nm. The AFM obviously depicts the formation of the rutile and anatase forms in the TiO(2) NPs and also, the surface morphology of the particles is uneven due to the presence of some of the aggregates and individual particles. Adulticidal parasitic activity was observed in varying concentrations of aqueous leaf extract of C. roseus, TiO(2) solution, and synthesized TiO(2) NPs for 24 h. The maximum parasitic activity was observed in aqueous crude leaf extracts of C. roseus against the adults of H. maculata and B. ovis with LD(50) values of 36.17 and 30.35 mg/L, and r (2) values of 0.948 and 0.908, respectively. The highest efficacy was reported in 5 mM TiO(2) solution against H. maculata and B. ovis (LD(50) = 33.40 and 34.74 mg/L; r (2) = 0.786 and 0.873), respectively, and the maximum activity was observed in the synthesized TiO(2) NPs against H. maculata and B. ovis with LD(50) values of LD(50) = 7.09 and 6.56 mg/L, and r (2) values of 0.880 and 0.913, respectively. This method is considered as an innovative alternative approach to control the hematophagous fly and sheep-biting louse.


Assuntos
Catharanthus/metabolismo , Dípteros/efeitos dos fármacos , Inseticidas/metabolismo , Iscnóceros/efeitos dos fármacos , Nanopartículas , Extratos Vegetais/metabolismo , Titânio/metabolismo , Animais , Bioensaio , Inseticidas/química , Inseticidas/farmacologia , Dose Letal Mediana , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Folhas de Planta/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Análise de Sobrevida , Titânio/química , Titânio/farmacologia , Difração de Raios X
17.
Parasitol Res ; 111(5): 2023-33, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21993881

RESUMO

In the present work, we describe inexpensive, nontoxic, unreported and simple procedure for synthesis of silver nanoparticles (Ag NPs) using leaf aqueous extract of Lawsonia inermis as eco-friendly reducing and capping agent. The aim of the present study was to assess the lousicidal activity of synthesized Ag NPs against human head louse, Pediculus humanus capitis De Geer (Phthiraptera: Pediculidae), and sheep body louse, Bovicola ovis Schrank (Phthiraptera: Trichodectidae). Direct contact method was conducted to determine the potential of pediculocidal activity and impregnated method was used with slight modifications to improve practicality and efficiency of tested materials of synthesized Ag NPs against B. ovis. The synthesized Ag NPs characterized with the UV showing peak at 426 nm. X-ray diffraction (XRD) spectra clearly shows that the diffraction peaks in the pattern indexed as the silver with lattice constants. XRD analysis showed intense peaks at 2θ values of 38.34°, 44.59°, 65.04°, and 77.77° corresponding to (111), (200), (220), and (311) Bragg's reflection based on the fcc structure of Ag NPs. Fourier transform infrared spectroscopy (FTIR) spectra of Ag NPs exhibited prominent peaks at 3,422.13, 2,924.12, 2,851.76, 1,631.41, 1,381.60, 1,087.11, and 789.55 cm(-1). Scanning electron microscopy (SEM) micrograph showed mean size of 59.52 nm and aggregates of spherical shape Ag NPs. Energy dispersive X-ray spectroscopy (EDX) showed the complete chemical composition of the synthesized Ag NPs. In pediculocidal activity, the results showed that the optimal times for measuring percent mortality effects of synthesized Ag NPs were 26, 61, 84, and 100 at 5, 10, 15, and 20 min, respectively. The average percent mortality for synthesized Ag NPs was 33, 84, 91, and 100 at 10, 15, 20, and 35 min, respectively against B. ovis. The maximum activity was observed in the aqueous leaf extract of L. inermis, 1 mM AgNO(3) solution, and synthesized Ag NPs against P. humanus capitis with LC(50) values of 18.26, 7.77, and 1.33 mg l(-1) and r (2) values of 0.863, 0.900, and 0.803 and against B. ovis showed with LC(50) values of 21.19, 8.49, and 1.41 mg l(-1) and r (2) values of 0.920, 0.938 and 0.870, respectively. The findings revealed that synthesized Ag NPs possess excellent anti-lousicidal activity.


Assuntos
Inseticidas/farmacologia , Iscnóceros/efeitos dos fármacos , Lawsonia (Planta)/metabolismo , Nanopartículas , Pediculus/efeitos dos fármacos , Prata/farmacologia , Animais , Inseticidas/isolamento & purificação , Microscopia Eletrônica de Varredura , Testes de Sensibilidade Parasitária , Extratos Vegetais/metabolismo , Folhas de Planta/metabolismo , Prata/química , Prata/metabolismo , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Análise de Sobrevida , Difração de Raios X
18.
Parasitol Res ; 108(6): 1437-45, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21136078

RESUMO

Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. The aim of this study was to evaluate the adulticidal activity and adult emergence inhibition (EI) of leaf hexane, chloroform, ethyl acetate, acetone, and methanol extracts of Aegle marmelos (Linn.) Correa ex Roxb, Andrographis lineata Wallich ex Nees., Andrographis paniculata (Burm.f.) Wall. ex Nees., Cocculus hirsutus L. Diels, Eclipta prostrata L., and Tagetes erecta L. tested against malarial vector, Anopheles subpictus Grassi (Diptera: Culicidae). All plant extracts showed moderate adulticidal activity and EI effects after 24 h of exposure at 1,000 ppm; however, the highest adulticidal activity was observed in ethyl acetate extract of A.lineata, chloroform extract of A. paniculata, acetone extract of C. hirsutus, and methanol extract of T. erecta (LD(50) = 126.92, 95.82, 109.40, and 89.83 ppm; LD(90) = 542.95, 720.82, 459.03, and 607.85 ppm); and effective EI was found in leaf acetone extract of the A. marmelos, ethyl acetate extract of A. lineata, methanol extracts of C. hirsutus, and T. erecta, (EI(50) = 128.14, 79.39, 143.97, and 92.82 ppm; EI(90) = 713.53, 293.70, 682.72, and 582.59 ppm), respectively, against A. subpictus. These results suggest that the leaf methanol extract of C. hirsutus and T. erecta have the potential to be used as an ideal eco-friendly approach for the control of A. subpictus. Therefore, this study provides first report on the mosquito adulticidal activity and EI of plant extracts against malaria vector.


Assuntos
Anopheles/efeitos dos fármacos , Inseticidas/farmacologia , Extratos Vegetais/farmacologia , Animais , Controle de Mosquitos , Plantas Medicinais/química
19.
Parasitol Res ; 109(1): 37-45, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21161270

RESUMO

The source of chemical anthelmintics (levamisole, flubendazole, and thiabendazole) had limited the success of gastrointestinal nematodiasis control in sheep and goats and thus awakened interest in the study of medicinal plant extracts as alternative sources of anthelmintics. The egg hatching and larvicidal effect of indigenous plant extracts were investigated against the sheep parasite, Haemonchus contortus. The purpose of the present study was to assess the efficacy of leaf, bark, and seed ethyl acetate, acetone and methanol extracts of Andrographis paniculata (Burm.f.) Wall. ex Nees., Anisomeles malabarica (L.) R. Br., Annona squamosa L., Datura metel L., and Solanum torvum Swartz were tested against the parasitic nematode of small ruminants H. contortus using egg hatch assay (EHA) and larval development assay (LDA). The assays were run in 24-well cell culture plates at room temperature with five replicates. All plant extracts showed moderate parasitic effects after 48 and exposure for egg hatching and LDA, respectively; however, 100% egg hatching and larvicidal inhibition were found in the methanol extracts of A. paniculata, A. squamosa, D. metel, and S. torvum at 25 mg/ml and the effect was similar to positive control of Albendazole (0.075 mg/ml) and Ivermectin (0.025mg/ml) against H. contortus, respectively. The EHA result showed the ED(50) of methanol extracts of A. paniculata and D. metel, which were 2.90 and 3.08 mg/ml, and in larval development assay, the ED(50) was 4.26 and 3.86 mg/ml, respectively. These effects remain to be confirmed through in vivo studies.


Assuntos
Anti-Helmínticos/farmacologia , Gleiquênias/química , Haemonchus/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Anti-Helmínticos/isolamento & purificação , Casca de Planta/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química , Sementes/química , Análise de Sobrevida
20.
Parasitol Res ; 109(3): 715-26, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21373809

RESUMO

This no-choice, laboratory study focuses on the feeding of homogeneous powdered, dried, yeast with different plant extracts on mosquito fourth-instar larvae to determine the effects on their mortality. Screening for antifeedant activity of plant extracts with some known medicinal attributes could lead to the discovery of new agents for vector control. The aim of this study was to investigate the antifeedant activity of crude leaf hexane, ethyl acetate, acetone, and methanol extracts of Andrographis lineata Wallich ex Nees. (Acanthaceae), Anisomeles malabarica (L.) Sims. (Lamiaceae), Argemone mexicana L. (Papaveraceae), Aristolochia bracteolata Lam. (Aristolochiaceae), Chrysanthemum indium L. (Asteraceae), Datura metal L. (Solanaceae), Eclipta prostrata L. (Asteraceae), and Sesbania grandiflora (L.) Pers. (Fibaceae) against the fourth-instar larvae of Anopheles subpictus Grassi (Diptera:Culicidae). All the crude extracts showed antifeedant activity in a dose-dependent manner. The plant extracts exhibited a significant antifeedant activity after 24 and 48 h of exposure; however, the highest larval mortality was found in leaf ethyl acetate extract of A. malabarica, acetone extract E. prostrata, methanol extract of A. lineata, C. indium, and S. grandiflora after 24 h (LC(50) = 2.53, 2.82, 2.31, 2.56, and 2.08 mg/mL; LC(90) = 6.40, 8.06, 7.45, 6.98, and 6.20 mg/mL), respectively. The hexane extract of A. lineata, D. metal, methanol extract of A. bracteolata and E. prostrata showed larval mortality after 48 h (LC(50) = 3.05, 2.11, 3.00, and 2.18 mg/mL; LC(90) = 9.06, 6.22, 8.23, and 5.77 mg/mL), respectively. One hundred percent larval mortality was observed in methanol extract of A. lineata, and C. indium after 24 h and the hexane extract of A. lineata and D. metal after 48 h at 10 mg/100 mL. The methanol extracts of A. lineata and C. indium significantly increased larval mortality in comparison to larvae fed with untreated diet. Bacillus thuringiensis subsp. israelensis is widely accepted as a biological pesticide because of its highly specific activity against dipteran insects without adverse effects on other organisms. The feeding deterrent activity of different herbal extracts against the larvae of malaria vector A. subpictus exhibited significantly lower toxicity compare with the bio larvicides, B. thuringiensis. These results suggest that the methanol extract of A. lineata, C. indium, the hexane extract of A. lineata and D. metal have the potential to be used as an ideal eco-friendly approach for the control of the medically important vector A. subpictus. These findings corroborate traditional insecticidal application of selected plants and the results can be extended for the control of mosquitoes.


Assuntos
Anopheles/efeitos dos fármacos , Repelentes de Insetos/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Comportamento Alimentar/efeitos dos fármacos , Repelentes de Insetos/isolamento & purificação , Larva/efeitos dos fármacos , Programas de Rastreamento/métodos , Extratos Vegetais/isolamento & purificação , Análise de Sobrevida
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA