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1.
Rev. Soc. Bras. Med. Trop ; 53: e20190211, 2020. tab, graf
Article in English | LILACS | ID: biblio-1057287

ABSTRACT

Abstract INTRODUCTION Anopheles stephensi is the main malaria vector in Southeast Asia. Recently, plant-sourced larvicides are attracting great interests. METHODS: The essential oil was extracted from the leaf of Cinnamomum camphora (L.), and a bioassay was conducted to determine the larvicidal efficacy. The chemical composition of the essential oil was determined by GC-MS analysis. RESULTS: The oil showed strong, dose-dependent larvicidal activities. The onset of larvicidal efficiency was rapid. The LC50 and LC95 were determined as 0.146% and 1.057% at 1 h, 0.031% and 0.237% at 12 h, 0.026% and 0.128% at 24 h, respectively. The oil contains 32 compounds. CONCLUSIONS The essential oil of C. camphora leaf has an excellent larvicidal potential for the control of A. stephensi.


Subject(s)
Animals , Oils, Volatile/pharmacology , Cinnamomum camphora/chemistry , Mosquito Vectors/drug effects , Insecticides/pharmacology , Larva/drug effects , Anopheles/drug effects , Biological Assay , Oils, Volatile/isolation & purification , Mosquito Vectors/classification , Insecticides/isolation & purification , Lethal Dose 50 , Anopheles/classification
2.
Rev. Soc. Bras. Med. Trop ; 53: e20190018, 2020. graf
Article in English | LILACS | ID: biblio-1092184

ABSTRACT

Abstract INTRODUCTION: The larvicidal potential of Saussurea costus (Falc.) Lipsch. was studied against the early 4th instar larvae of Anopheles stephensi Liston., Aedes aegypti Linn.,and Culex quinquefasciatus Say. because of the emergence of mosquito resistance to conventional synthetic insecticides. METHODS: At concentrations of 12.5-200 ppm, larvicidal activities were studied under laboratory conditions. RESULTS: After 24 h of exposure, the methanol extract of the roots recorded the highest larvicidal activity against An. stephensi, with LC50 and LC90values of 7.96 and 34.39 ppm, respectively. CONCLUSIONS: We are developing potent larvicidal compound(s) from S. costus for controlling the mosquito larval population.


Subject(s)
Animals , Plant Extracts/pharmacology , Aedes/drug effects , Culex/drug effects , Saussurea/chemistry , Insecticides/pharmacology , Larva/drug effects , Anopheles/drug effects , Insecticides/isolation & purification
3.
Rev. Soc. Bras. Med. Trop ; 52: e20180197, 2019. tab
Article in English | LILACS | ID: biblio-1041584

ABSTRACT

Abstract INTRODUCTION: Aedes aegypti and Aedes albopictus are important vectors that transmit arboviruses to human populations. METHODS: Natural products were obtained and tested against larvae collected from the field in Fortaleza, capital of Ceará state. RESULTS: The essential oils of Syzygium aromaticum (Ae. aegypti LC50 = 32.7 ppm and Ae. albopictus LC50 = 138.1 ppm) and Croton nepetaefolius (Ae. aegypti LC50 = 81.7 ppm and Ae. albopictus LC50 = 76.1 ppm) showed the most intense larvicidal activity. CONCLUSIONS: The essential oils and methyl esters showed greater larvicidal activity than did the ethanol extracts.


Subject(s)
Animals , Plant Oils/isolation & purification , Oils, Volatile/pharmacology , Aedes/drug effects , Insecticides/pharmacology , Plant Oils/classification , Plant Oils/pharmacology , Oils, Volatile/isolation & purification , Oils, Volatile/classification , Insecticides/isolation & purification , Larva/drug effects , Lethal Dose 50
4.
Rev. Soc. Bras. Med. Trop ; 52: e20180459, 2019. tab, graf
Article in English | LILACS | ID: biblio-1041559

ABSTRACT

Abstract INTRODUCTION: The ability of Vitex trifolia and Vitex negundo essential oils to kill Aedes aegypti and Culex quinquefasciatus larvae was evaluated. METHODS: The larvae were treated with their respective essential oils at 50-125 ppm concentration. RESULTS: LC50 and LC90 for V. trifolia against Ae. aegypti and C. quinquefasciatus, and those for V. negundo against Ae. aegypti were 57.7+0.4, 77.9+0.9 ppm and 55.17+3.14, 78.28+2.23 ppm, and 50.86+0.9, 73.12+1.3 ppm, respectively. Eucalyptol and caryophyllene were the major components in Vitex trifolia and Vitex negundo essential oil, respectively. CONCLUSIONS: This study revealed potential larvicidal properties of essential oil from V. trifolia.


Subject(s)
Animals , Oils, Volatile/pharmacology , Aedes/drug effects , Vitex/chemistry , Mosquito Vectors/drug effects , Insecticides/pharmacology , Larva/drug effects , Oils, Volatile/isolation & purification , Insecticides/isolation & purification , Lethal Dose 50
5.
An. acad. bras. ciênc ; 89(3): 1869-1879, July-Sept. 2017. tab, graf
Article in English | LILACS | ID: biblio-886768

ABSTRACT

ABSTRACT Piper aduncum found naturally in the Amazon and southeastern Brazil, is known for its secondary metabolites that have activity on insects. Anticarsia gemmatalis and Spodoptera frugiperda are among the major insect pests associated with agricultural production. This research evaluated the biological activity of hexane, ethyl acetate, and ethanol extracts of P. aduncum leaves on mortality and duration of larval and pupal periods, as well as weight, width, and length of A. gemmatalis and S. frugiperda pupae. The mortality of A. gemmatalis larvae in trials with P. aduncum extracts were 93.3% (hexane) and 90% (ethyl acetate), estimating LC50 of 6.35 and 5.79 mg/mL, respectively. Mortality in S. frugiperda submitted to the hexane extract ranged from 3.33% to 96.66% (LC50 of 8.22 mg/mL). The ethanol extract induced low mortality (3.33% to 23.33%). The P. aduncum extracts did not affect the development of S. frugiperda pupae. In A. gemmatalis differences in weight and length occurred. The chemical characterization was by GC-MS, which revealed that the major constituent in the hexane extract of P. aduncum was apiol (90.7%). P. aduncum extracts are important and promising components to manage A. gemmatalis and S. frugiperda, which cause extensive production losses.


Subject(s)
Animals , Plant Extracts/pharmacology , Spodoptera/drug effects , Piper/chemistry , Insecticides/pharmacology , Lepidoptera/drug effects , Insecticides/isolation & purification
6.
Rev. Soc. Bras. Med. Trop ; 49(6): 687-692, Dec. 2016. tab, graf
Article in English | LILACS | ID: biblio-829677

ABSTRACT

Abstract: INTRODUCTION: The significant increase in dengue, Zika, and chikungunya and the resistance of the Aedes aegypti mosquito to major insecticides emphasize the importance of studying alternatives to control this vector. The aim of this study was to develop a controlled-release device containing Piper nigrum extract and to study its larvicidal activity against Aedes aegypti. METHODS: Piper nigrum extract was produced by maceration, standardized in piperine, and incorporated into cotton threads, which were inserted into hydrogel cylinders manufactured by the extrusion of carrageenan and carob. The piperine content of the extract and thread reservoirs was quantified by chromatography. The release profile from the device was assessed in aqueous medium and the larvicidal and residual activities of the standardized extract as well as of the controlled-release device were examined in Aedes aegypti larvae. RESULTS The standardized extract contained 580mg/g of piperine and an LC50 value of 5.35ppm (24h) and the 3 cm thread reservoirs contained 13.83 ± 1.81mg of piperine. The device showed zero-order release of piperine for 16 days. The P. nigrum extract (25ppm) showed maximum residual larvicidal activity for 10 days, decreasing progressively thereafter. The device had a residual larvicidal activity for up to 37 days. CONCLUSIONS: The device provided controlled release of Piper nigrum extract with residual activity for 37 days. The device is easy to manufacture and may represent an effective alternative for the control of Aedes aegypti larvae in small water containers.


Subject(s)
Animals , Plant Extracts/administration & dosage , Aedes/drug effects , Piper nigrum/chemistry , Insect Vectors/drug effects , Insecticides/administration & dosage , Drug Delivery Systems , Delayed-Action Preparations , Dengue/transmission , Insecticides/isolation & purification , Larva/drug effects , Lethal Dose 50
7.
Rev. Soc. Bras. Med. Trop ; 49(6): 693-697, Dec. 2016. tab, graf
Article in English | LILACS | ID: biblio-829668

ABSTRACT

Abstract: INTRODUCTION: Dengue fever is a viral disease transmitted by the Aedes aegypti Linn. (1792) (Diptera: Culicidae) mosquito, which is endemic in several regions of Brazil. Alternative methods for the control of the vector include botanical insecticides, which offer advantages such as lower environmental contamination levels and less likelihood of resistant populations. Thus, in this study, the ability of botanical insecticide formulations to inhibit the activity of the liver enzymes serum cholinesterase and malate dehydrogenase was evaluated. METHODS: Inhibition profiles were assessed using in vitro assays for cholinesterase and malate dehydrogenase activity and quantitated by ultraviolet-visible spectroscopy at 410nm to 340nm. RESULTS Insecticide products formulated from cashew nutshell liquid [A] and ricinoleic acid [B] showed cholinesterase activity levels of 6.26IU/mL and 6.61IU/mL, respectively, while the control level for cholinesterase was 5-12IU/mL. The products did not affect the level of 0.44IU/mL established for malate dehydrogenase, as the levels produced by [A] and [B] were 0.43IU/mL and 0.45IU/mL, respectively. CONCLUSIONS Our findings show that in vitro testing of the formulated products at concentrations lethal to A. aegypti did not affect the activity of cholinesterase and malate dehydrogenase, indicating the safety of these products.


Subject(s)
Humans , Animals , Ricinoleic Acids/pharmacology , Cholinesterase Inhibitors/pharmacology , Cholinesterases/drug effects , Anacardium/chemistry , Insecticides/pharmacology , Liver/enzymology , Malate Dehydrogenase/antagonists & inhibitors , Spectrophotometry, Ultraviolet , In Vitro Techniques , Ricinoleic Acids/isolation & purification , Aedes , Insect Vectors/drug effects , Insecticides/isolation & purification
8.
Braz. j. microbiol ; 46(4): 1087-1091, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769654

ABSTRACT

Abstract Carbaryl is an important and widely used insecticide that pollutes soil and water systems. Bacteria from the local soil ecosystem of the Gaza Strip capable of utilizing carbaryl as the sole source of carbon and nitrogen were isolated and identified as belonging to Bacillus, Morganella, Pseudomonas, Aeromonas and Corynebacterium genera. Carbaryl biodegradation by Bacillus, Morganella and Corynebacterium isolates was analyzed in minimal liquid media supplemented with carbaryl as the only source of carbon and nitrogen. Bacillus and Morganella exhibited 94.6% and 87.3% carbaryl degradation, respectively, while Corynebacterium showed only moderate carbaryl degradation at 48.8%. These results indicate that bacterial isolates from a local soil ecosystem in the Gaza Strip are able to degrade carbaryl and can be used to decrease the risk of environmental contamination by this insecticide.


Subject(s)
Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Bacteria/metabolism , Biodegradation, Environmental/classification , Biodegradation, Environmental/genetics , Biodegradation, Environmental/isolation & purification , Biodegradation, Environmental/metabolism , Carbaryl/classification , Carbaryl/genetics , Carbaryl/isolation & purification , Carbaryl/metabolism , Ecosystem/classification , Ecosystem/genetics , Ecosystem/isolation & purification , Ecosystem/metabolism , Insecticides/classification , Insecticides/genetics , Insecticides/isolation & purification , Insecticides/metabolism , Middle East/classification , Middle East/genetics , Middle East/isolation & purification , Middle East/metabolism , Soil Microbiology/classification , Soil Microbiology/genetics , Soil Microbiology/isolation & purification , Soil Microbiology/metabolism , Soil Pollutants/classification , Soil Pollutants/genetics , Soil Pollutants/isolation & purification , Soil Pollutants/metabolism
9.
Rev. biol. trop ; 61(1): 419-427, Mar. 2013. tab
Article in English | LILACS | ID: lil-674091

ABSTRACT

The use of synthetic insecticides for insect control may lead to different kind of problems, such as vector resistance to insecticides. To avoid these problems, a new research area to study botanical products as possible disease vectors controls, has become a feasible alternative. The purpose of this research was to evaluate the biocide activity of the ethanol extract of seeds of Annona coriacea on Rhodnius neglectus (Chagas disease vector) nymphs and adults. For this, different concentrations extracts were evaluated: 25, 50, 100 and 200mg/ mL, and water in DMSO (20%) was used as control. The experimental design was completely randomized and we conducted the bioassay with nymphs and adults, with 10 nymphs and 10 adults (five males and five females) per treatment. Extract action was evaluated in both bioassays, in order to identify possible effects of mortality and life cycle interruption of nymphs and adults during a 28-day-period. The results obtained showed that the extract of A. coriacea was able to disrupt the development of nymphs and adults of R. neglectus, with a mortality rate of more than 90%, 36% and 100%, at the highest concentrations, respectively. There was also molting inhibition in nymphs, lower reproductive capacity in females, feeding deterrence and morphological changes in nymphs and adults. We concluded that the extract of A. coriacea has insecticide action on nymphs and adults of R. neglectus.


La enfermedad de Chagas se convirtió en un problema de salud debido a su importancia epidemiológica, es producida por el protista Trypanosoma cruzi, cuyos insectos vectores son del género Triatoma y Panstrongylus. El objetivo de este estudio fue evaluar la actividad biocida del extracto de Annona coriacea en las ninfas de Rhodnius neglectus y en sus adultos. Se evaluaron 14 concentraciones de 25, 50, 100 y 200mg/ml del extracto etanólico, así como el control, en este caso agua de DMSO (20%). Se utilizo un diseño completamente aleatorizado con tres repeticiones para el bioensayo con 10 ninfas y 10 adultos (cinco machos y cinco hembras) para cada tratamiento. La acción del extracto se observo durante 28 días en ambos bioensayos. Los resultados obtenidos mostraron que el extracto de A. coriacea fue capaz de interrumpir el desarrollo de las ninfas y adultos de R. neglectus, con una mortalidad de más del 90%, 36% y 100%, correspondiendo a las concentraciones más altas. También hubo inhibición de la muda de las ninfas, una menor capacidad reproductiva de las hembras, disuasión alimentaria y cambios morfológicos en las ninfas y adultos. Se concluye que el extracto de A. coriacea presentó acción insecticida en ninfas y adultos de R. neglectus.


Subject(s)
Animals , Female , Male , Annona/chemistry , Insect Vectors , Insecticides , Plant Extracts , Rhodnius , Chagas Disease/transmission , Dose-Response Relationship, Drug , Insecticides/isolation & purification , Seeds/chemistry
10.
Rev. Soc. Bras. Med. Trop ; 46(1): 84-87, Jan.-Feb. 2013. ilus, tab
Article in English | LILACS | ID: lil-666800

ABSTRACT

INTRODUCTION: The aim of the present study was to analyze the larvicidal activity of different crude extracts of Larrea cuneifolia and its most abundant lignan, nordihydroguaiaretic acid (NDGA), against Culex quinquefasciatus. METHODS: Chloroform, methanol, and aqueous extracts from L. cuneifolia and NDGA were tested against larvae of Cx. quinquefasciatus under laboratory conditions. RESULTS: The chloroform extract showed the highest larvicidal effect, with an estimated LC50 of 0.062 mg/ml. NDGA also demonstrated significant larvicidal activity with an estimated LC50 of 0.092 mg/ml. CONCLUSIONS: These results indicate that the chloroform extract of L. cuneifolia and NDGA are promising insecticides of botanical origin that could be useful for controlling Cx. quinquefasciatus.


Subject(s)
Animals , Culex/drug effects , Insect Vectors/drug effects , Insecticides/pharmacology , Larrea/chemistry , Masoprocol/pharmacology , Plant Extracts/pharmacology , Insecticides/isolation & purification , Larva/drug effects , Masoprocol/isolation & purification
11.
Rev. Soc. Bras. Med. Trop ; 44(2): 194-200, Mar.-Apr. 2011. ilus
Article in Portuguese | LILACS | ID: lil-586107

ABSTRACT

INTRODUÇÃO: Dengue é um importante problema de saúde pública, em vários países, e tem como principal vetor o Aedes aegypti, mosquito mais adaptado às áreas urbanizadas. Apresenta-se, pela primeira vez, as alterações ultraestruturais em larvas de 3º estádio, desse mosquito, causadas pelos larvicidas naturais, um diterpeno labdano, extraído de Copaifera reticulata, e uma fração rica em taninos catéquicos, extraída de Magonia pubescens, evidenciando o mecanismo de ação dessas substâncias. MÉTODOS: Os experimentos foram realizados com larvas de 3º estádio em solução de 0,9ppm, do diterpeno (3-β-acetoxylabdan-8(17)-13-dien-15-óico) e de 3,7ppm, da fração majoritária de tanino catéquico de massa molecular 864Da. Obtiveram-se as substâncias através de fracionamentos cromatográficos sucessivos, identificadas por ressonância magnética nuclear de hidrogênio e espectrometria de massas. As larvas que atingiram estado letárgico foram coletadas e dissecadas e seus tubos digestórios fixados, desidratados, emblocados e polimerizados. Cortes ultrafinos foram feitos e contrastados com acetato de uranila 3 por cento e citrato de chumbo, posteriormente, levados ao microscópio eletrônico. RESULTADOS: As principais alterações ultraestruturais provocadas pelos diterpeno e tanino sobre larvas de Aedes aegypti foram vacuolização citoplasmática, desorganização e degeneração celular, mudança estrutural dos microvilos e deslocamento das células da lâmina basal. CONCLUSÕES: O diterpeno e a fração rica em taninos catéquicos provocaram a morte das larvas de Aedes aegypti através da destruição celular no intestino médio.


INTRODUCTION: Dengue is an important public health problem in many countries and its main vector Aedes aegypti, is the mosquito most adapted to urban areas. For the first time, the mechanism of action of labdane diterpenoid extracted from Copaifera reticulata and the fraction enriched of catechin tannins extracted from Magonia pubescens is demonstrated through ultrastructural alterations of Aedes aegypti larvae. METHODS: Experiments were performed using a 0.9ppm solution of diterpenoid and 3.7ppm of the fraction as the main catechin tannin of molecular mass 846Da. The compounds were obtained by thin layer chromatography and identified by nuclear magnetic resonance of hydrogen and mass spectrometry. Larvae that achieved lethargic state were collected and dissected. Next, they were contrasted with 1 percent uranyl acetate, dehydrated, embedded and polymerized. Ultrathin sections were made, mixed with 3 percent uranyl acetate and lead citrate and placed in an electron microscope. RESULTS: The main ultrastructural alterations caused by the diterpenoid and by tanins in larvae of Aedes aegypti were: cytoplasmic vacuolation, alteration of microvilli, cellular aging, cell disruption and degeneration, formation of secretion vesicles and structural changes in microvilli, irregular nuclei and displacement of cells in the basal lamina. CONCLUSIONS: The fraction containing tannins and the diterpenoid caused the death of Aedes aegypti larvae by cell destruction in the midgut.


Subject(s)
Animals , Aedes/drug effects , Diterpenes/pharmacology , Fabaceae/chemistry , Insecticides , Plant Extracts/pharmacology , Sapindaceae/chemistry , Tannins/pharmacology , Aedes/growth & development , Aedes/ultrastructure , Diterpenes/isolation & purification , Insecticides/isolation & purification , Intestines/drug effects , Intestines , Larva/drug effects , Larva/ultrastructure , Magnetic Resonance Spectroscopy , Mass Spectrometry , Tannins/isolation & purification
12.
Iranian Journal of Public Health. 2011; 40 (4): 122-128
in English | IMEMR | ID: emr-122916

ABSTRACT

Organophosphorus pesticides are one of the most prevalent usages for pest control in the country. Such pesticides enter into water sources by different routes. Since drinking of contaminated water at the higher doses than the standard level, may causes undesirable effects to human health and ecosystem. The object of this research was to investigate the effect of various parameters including time, power and concentration on sonodecomposition of malathion insecticide in the water. The sonochemical degradation of malathion was investigated using acoustic wave technology [AWT]. AWT with 130 kHz was used to study the decomposition of insecticide solution. Samples were analyzed using HPLC at different intervals times. Effectiveness of AWT at different times [20, 40, 60, 80, 100, and 120 minutes], concentrations of malathion at 2, 4 and 8 mg/L as well as powers of device [300W, 400W, 500W] are compared. These findings showed that the degradation of the malathion insecticide at lower concentrations was greater in comparison to higher concentrations. Also, there was positive correlation between power increasing and the ability to malathion degradation. The sonodegradation of malathion at different concentrations and powers was successfully achieved. It has been shown that acoustical wave technology can be used to reduce the concentration of dissolved insecticide using high frequency


Subject(s)
Insecticides/isolation & purification , Water Pollutants, Chemical/isolation & purification , Water Pollution, Chemical/prevention & control , Sound , Water Purification , Organophosphorus Compounds/isolation & purification , Waste Management , Pesticides/isolation & purification
13.
Article in English | WPRIM | ID: wpr-151031

ABSTRACT

Growing patterns of pediculocidal drug resistance towards head louse laid the foundation for research in exploring novel anti-lice agents from medicinal plants. In the present study, various extracts of Pongamia pinnata leaves were tested against the head louse Pediculus humanus capitis. A filter paper diffusion method was conducted for determining the potential pediculocidal and ovicidal activity of chloroform, petroleum ether, methanol, and water extracts of P. pinnata leaves. The findings revealed that petroleum ether extracts possess excellent anti-lice activity with values ranging between 50.3% and 100% where as chloroform and methanol extracts showed moderate pediculocidal effects. The chloroform and methanol extracts were also successful in inhibiting nymph emergence and the petroleum ether extract was the most effective with a complete inhibition of emergence. Water extract was devoid of both pediculocidal and ovicidal activities. All the results were well comparable with benzoyl benzoate (25% w/v). These results showed the prospect of using P. pinnata leave extracts against P. humanus capitis in difficult situations of emergence of resistance to synthetic anti-lice agents.


Subject(s)
Animals , Drug Evaluation, Preclinical , Insecticides/isolation & purification , Phthiraptera/drug effects , Millettia/chemistry , Plant Extracts/isolation & purification , Plant Leaves/chemistry , Survival Analysis
14.
Egyptian Journal of Pharmaceutical Sciences. 2008; 49: 35-48
in English | IMEMR | ID: emr-135326

ABSTRACT

A sensitive high performance liquid chromatographic method using ultraviolet detector has been developed for the determination of methomyl insecticide residues on tomato and cucumber fruits. The developed method consisted of extraction with ethyl acetate, adsorption clean up [by adsorbing mixture consisting of charcoal/celite in ratio 2: 1], followed by high performance liquid chromatographic determination using methanol: water [1: 1] as a mobile phase and UV detection at 233 nm. The range of percentage recovery was between 88.2% and 90.4% for both plant samples. [These recoveries are good for those types of extraction of pesticides traces from plant materials, refer to [1] to compare recoveries]. The method was applied to determine residues and rate of decline of methomyl from fruits of tomatoes and cucumber [open field and greenhouse treatment, with methomyl formulation [Lannate 90% SP] for 100 liter water]. The insecticide incorporated into the plants decreased rapidly with a half-life around 1 day in winter and 0.5 day in summer


Subject(s)
Lycopersicon esculentum/toxicity , Cucumis sativus/toxicity , Insecticides/isolation & purification , /methods
15.
An. acad. bras. ciênc ; 79(2): 209-213, June 2007. tab
Article in English | LILACS | ID: lil-454591

ABSTRACT

The chemical composition of the essential oils from aerial parts of Pectis apodocephala and Pectis oligocephala were analyzed by GC-MS. The essential oils of these species were predominantly constituted by monoterpenes. Geranial (42.9-44.5 percent), neral (32.2-34.2 percent) and alpha-pinene (10.7-11.4 percent) were the main constituents in the oil of P. apodocephala, while p-cymene (50.3-70.9 percent) and thymol (24.4-44.7 percent), were the prevalent compounds in the oil of P. oligocephala. The essential oils were tested against the root knot nematode Meloidogyne incognita and Aedes aegypti larvae survival. The results obtained show that both essential oils exhibited significant activity and could be considered as potent natural namaticidal and larvicidal agents.


A composição química dos óleos essenciais das partes aéreas de Pectis apodocephala e Pectis oligocephala foi analisada por CG-EM. Os óleos essenciais destas espécies foram predominantemente constituídos por monoterpenos. Geranial (42, 9-44, 5 por cento), neral (32, 2-34, 2 por cento) e alfa-pineno (10, 7-11, 4 por cento) foram os constituintes majoritários no óleo de P. apodocephala, enquanto p-cimeno (50, 3-70, 9 por cento) e timol (24, 4-44, 7 por cento), foram os compostos prevalentes no óleo de P. oligocephala. Ambos os óleos foram testados contra o nematóide Meloidogyne incognita e larvas do mosquito Aedes aegypti no terceiro estágio. Os resultados obtidos mostraram que os óleos exibem significante atividade e podem, portanto, ser considerados como potenciais agentes nematicida e larvicida naturais.


Subject(s)
Animals , Aedes/drug effects , Antinematodal Agents/pharmacokinetics , Insecticides/pharmacology , Oils, Volatile/pharmacology , Tylenchoidea/drug effects , Aedes/growth & development , Antinematodal Agents/isolation & purification , Insecticides/isolation & purification , Larva/drug effects , Oils, Volatile/chemistry , Oils, Volatile/isolation & purification , Plant Leaves/chemistry , Time Factors
16.
An. acad. bras. ciênc ; 79(1): 35-39, Mar. 2007. tab
Article in English | LILACS | ID: lil-445583

ABSTRACT

The effect of 2-tridecanone vapor on the cowpea weevil (Callosobruchus maculatus) development was determined. Seeds of cowpea were infested with adults and exposed to different doses of 2-tridecanone isolated from Pilocarpus microphyllus Stapf ex Holm, a plant species native from northeastern Brazil. The pure monoterpene was evaluated both undiluted as well as in the dilutions 1:10, 1:100 and 1:1,000 (v/v). The following parameters of the cowpea weevil life cycle were analyzed in response to decreasing doses of 2-tridecanone: number of eggs laid, percentage of egg hatching on seeds, percentage of adult emergence, adult weight at emergence, mean developmental time and number of adults emerged. Vapor of 2-tridecanone caused a significant (P < 0.05) reduction in the number of eggs laid, in the percentage of eggs hatched and in the number of emerged adults in infested seeds. The fumigant insecticidal effect of 2-tridecanone was mainly due to its ovicidal activity.


O efeito dos vapores da 2-tridecanona sobre o caruncho do feijão-de-corda (Callosobruchus maculatus) foi avaliado. Sementes de feijão-de-corda infestados com insetos adultos foram expostas a diferentes doses de 2-tridecanona isolada de Pilocarpus microphyllus, uma espécie nativa do Nordeste do Brasil. O monoterpeno puro foi utilizado nas diluições 1:10, 1:100 e 1:1000 (v/v). Os parâmetros da biologia do inseto foram analisados em função da resposta a doses decrescentes de 2-tridecanona: número de ovos postos por fêmea, percentagem de eclosão de ovos, percentagem de emergência de adultos, peso dos adultos recém-emergidos, tempo médio de desenvolvimento e número total de ovos emergidos. Diferenças significativas (P < 0.05) entre as doses de 2-tridecanona testadas foram observadas, para quatro dos seis parâmetros biológicos analisados. Os resultados obtidos indicaram que a 2-tridecanona é tóxica para C. maculatus, reduzindo significativamente (P < 0.05) o número de insetos emergidos após a infestação. Esse efeito foi causado principalmente pela significativa redução observada na eclosão dos ovos expostos ao vapor da substância.


Subject(s)
Animals , Female , Insecticides/administration & dosage , Ketones/administration & dosage , Phaseolus/parasitology , Pilocarpus/chemistry , Weevils , Insecticides/isolation & purification , Ketones/isolation & purification , Oviposition/drug effects
17.
Indian J Exp Biol ; 2006 Aug; 44(8): 662-5
Article in English | IMSEAR | ID: sea-62482

ABSTRACT

The larvicidal activity of ethanol, chloroform and hexane soxhlet extracts obtained from S. guttata seeds was investigated against the IVth instar larvae of Dengue fever vector, Aedes aegypti and filarial vector, Culex quinquefasciatus. All extracts including fractions of ethanol extract exhibited 100% larval kill within 24 hr exposure period at 500 ppm concentration. Fraction A1 of ethanol was found to be most promising; its LC50 was 21.552 and 35.520 ppm against C. quinquefasciatus and A. aegypti respectively. Naturally occurring S. guttata seed derived fractions merit further study as potential mosquito larval control agents or lead compounds.


Subject(s)
Animals , Culicidae/drug effects , Insecticides/isolation & purification , Larva/drug effects , Plant Extracts/toxicity , Seeds/chemistry , Sterculia/chemistry
18.
J Environ Biol ; 2006 Jan; 27(1): 103-5
Article in English | IMSEAR | ID: sea-113279

ABSTRACT

Leaves of Artemisia annua linn. and Azadirachta indica were extracted in petroleum ether and hexane respectively by different methods of extraction i.e. cold extraction, reflux extraction and soxhlet extraction. The crude extract obtained was tested against third instar larvae of Anopheles stephensi. On comparison of larval mortality of crude extract obtained by these three methods, both soxhlet and reflux extraction method showed 100% mortality at 200 ppm after 48 hr in case of A. annua. However LC50 (20 ppm) value of crude extract obtained by soxhlet extraction showed better results than reflux extraction (35 ppm) method after 72 hr. In case of A. indica, crude obtained by soxhlet showed 100% mortality (after 48 hr) at 250 ppm and LC50 of 69 ppm at 72 hr. Reflux extraction does not show any appreciable mortality even at 250 ppm concentration.


Subject(s)
Animals , Anopheles/drug effects , Artemisia annua/chemistry , Azadirachta/chemistry , Insecticides/isolation & purification , Larva/drug effects , Plant Extracts/isolation & purification , Plant Leaves/chemistry
19.
Rev. Soc. Bras. Med. Trop ; 37(5): 396-399, set.-out. 2004. ilus, tab
Article in Portuguese | LILACS | ID: lil-365847

ABSTRACT

Apresenta-se, pela primeira vez, o estudo fitoquímico das frações larvicidas, isoladas da Magonia pubescens, monitorado pelo estudo de eficácia sobre larvas de 3° estádio de Aedes aegypti, na busca de alternativas para o controle desse mosquito e obtenção de estruturas químicas passíveis de aprimoramento da atividade pela via sintética de outros derivados. As frações bioativas foram monitoradas quimicamente através de cromatografia de camada delgada, utilizando como revelador uma solução ácida de vanilina, e analisadas por ressonância magnética nuclear de hidrogênio e espectrometria de massas. Os bioensaios com as frações foram realizados em quintuplicata, à temperatura de 28±1°C, 80±5 por cento de umidade relativa e fotofase de 12 horas. As concentrações letais encontradas da fração MP-9, que apresentou o maior potencial larvicida, CL50 e CL90, foram de 3,1 e 36,6ppm, respectivamente. Todos os experimentos foram acompanhados por uma série controle, contendo o mesmo número de larvas.


Subject(s)
Humans , Aedes/drug effects , Insecticides , Sapindaceae/chemistry , Tannins , Chromatography, Thin Layer , Insecticides/isolation & purification , Lethal Dose 50 , Larva/drug effects , Mass Spectrometry , Tannins/isolation & purification
20.
Indian J Exp Biol ; 2000 Mar; 38(3): 290-2
Article in English | IMSEAR | ID: sea-63246

ABSTRACT

Effect of solvent residues of Vitex negundo L. and Cassia fistula L. leaves (0.5 and 1%) was studied on egg laying and adult emergence of Callosobruchus maculatus Fab. and on percentage of larval parasitism by Dinarmus vagabundus (Timberlake). Cowpea seeds treated with methanol and aqueous extract of Vitex, at these concentrations (0.5 and 1%), significantly reduced the number of eggs and emergence of F1 adults of C. maculatus. Both Vitex and Cassia extracts did not affect the percentage of parasitism by D. vagabundus on C. maculatus grubs.


Subject(s)
Animals , Coleoptera/parasitology , Cassia/chemistry , Fabaceae/parasitology , Hymenoptera/drug effects , Insecticides/isolation & purification , Plants, Medicinal , Vitex/chemistry
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