Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 97
Filter
1.
Bol. latinoam. Caribe plantas med. aromát ; 20(1): 38-50, 2021. tab, ilus
Article in English | LILACS | ID: biblio-1284405

ABSTRACT

This study evaluated the insecticidal activity of Gallesia integrifolia essential oil from fruits, leaves, and flowers against Aedes aegyptilarvae and pupae. The essential oil was obtained by hydrodistillation and characterized by gas chromatography-mass spectrometry. Sulfur compounds represented 95 to 99% of the essential oil from fruits, leaves, and flowers. Essential oil major compounds were 2,8-dithianonane (52.6%) in fruits, 3,5-dithiahexanol-5,5-dioxide (38.9%) in leaves, and methionine ethyl ester (45.3%) in flowers. The essential oils showed high activity against larvae, and low for pupae withLC99.9of 5.87 and 1476.67µg/mL from fruits; 0.0096 and 348.33 µg/mL from leaves and 0.021and 342.84 µg/mL from flowers, respectively. The main compound with insecticide activity is probably n-ethyl-1,3-dithioisoindole, from isoindole organothiophosphate class, found in greater amount in flower and leaf essential oil. The great insecticide activity of G. integrifolia essential oil suggests that this product is a natural insecticide.


Este estudio evaluó la actividad insecticida del aceite esencial de frutos, hojas y flores de Gallesia integrifolia contra larvas y pupas de Aedes aegypti. El aceite esencial se obtuvo por hidrodestilación y se caracterizó por cromatografía de gases acoplada a espectrometría de masas. Los compuestos de azufre representaron del 95 al 99% del aceite esencial de frutas, hojas y flores. Los compuestos principales del aceite esencial fueron 2,8-ditianonano (52,6%) en frutas, 3,5-ditiahexanol-5,5-dióxido (38,9%) en hojas y éster etílico de metionina (45,3%) en flores. Los aceites esenciales mostraron alta actividad contra larvas y baja para pupas con LC99.9de 5.87 y 1476.67µg/mL de frutos; 0,0096 y 348,33 µg/mL de hojas y 0,021 y342,84 µg/mL de flores, respectivamente. El principal compuesto con actividad insecticida es probablemente el n-etil-1,3-ditioisoindol, de la clase de los organotiofosfatos de isoindol, que se encuentra en mayor cantidad en el aceite esencial de flores y hojas. La gran actividad insecticida del aceite esencial de G. integrifolia sugiere que este producto es un insecticida natural.


Subject(s)
Animals , Oils, Volatile/pharmacology , Aedes/drug effects , Phytolaccaceae/chemistry , Insecticides/pharmacology , Terpenes/analysis , Oils, Volatile/chemistry , Cholinesterase Inhibitors , Plant Leaves/chemistry , Flowers/chemistry , Fruit/chemistry , Insecticides/chemistry , Gas Chromatography-Mass Spectrometry
2.
Rev. cuba. med. trop ; 72(1): e440, ene.-abr. 2020. graf
Article in Spanish | LILACS, CUMED | ID: biblio-1126697

ABSTRACT

Introducción: El Programa Nacional de Control de Aedes aegypti realiza actividades de rutina para controlar la trasmisión de arbovirosis en el país, pero siempre quedan poblaciones residuales del vector, que demandan de una vigilancia entomológica sostenible. Objetivo: Determinar la presencia de estadios inmaduros de Ae. aegypti en la provincia La Habana en el periodo 2013-2017. Métodos: Se realizó un análisis del número de criaderos larvales, detectados por los trabajadores del Programa Nacional de Control de Ae. aegypti, en La provincia La Habana entre 2013-2017. La frecuencia de los muestreos fue mensual y se siguió la metodología de encuestas del programa. Resultados: Al analizar el número de criaderos larvales por meses de los 15 municipios de provincia La Habana, se observó un incremento de estos en el periodo de junio a octubre en todos los años y un pico entre los meses de enero a marzo en los años 2014, 2016 y 2017. La incidencia de Ae. aegypti resultó homogénea al comparar las medias por año, excepto para el año 2015 en el cual se observó una disminución significativa en el número de criaderos en comparación solo con el año 2017. Conclusiones: A pesar del esfuerzo que realizan los trabajadores del programa, no se ha logrado una disminución significativa de criaderos de Ae. aegypti, lo que evidencia la necesidad de fortalecer los sistemas de vigilancia y mantener la sostenibilidad de las acciones para controlar de forma efectiva la trasmisión de arbovirosis en la provincia La Habana(AU)


Introduction: The National Aedes aegypti Control Program carries out routine activities to control the transmission of arbovirus infections in the country. However, there still exist residual populations of the vector which require sustainable entomological surveillance. Objective: Determine the presence of immature stage Ae. aegypti in the province of Havana in the period 2013-2017. Methods: An analysis was conducted of the number of larval breeding sites detected by workers from the National Ae. aegypti Control Program in the province of Havana in the period 2013-2017. Sampling was performed on a monthly basis following the surveying methodology of the Program. Results: Analysis of the data on larval breeding sites per month in the 15 municipalities of the province of Havana revealed an increase in their number in the June-October period of every year, and a peak between the months of January and March in the years 2014, 2016 and 2017. Comparison of mean values per year found that incidence of Ae. aegypti was homogeneous, except for the year 2015, when a significant decrease was observed in the number of breeding sites only with respect to the year 2017. Conclusions: Despite the effort made by workers from the Program, a significant reduction has not been achieved in the number of Ae. aegypti breeding sites, which is evidence of the need to strengthen the surveillance systems and maintain the sustainability of the actions performed to effectively control the transmission of arbovirus infections in the Havana province(AU)


Subject(s)
Pest Control, Biological/methods , Aedes/drug effects , Mosquito Vectors
3.
Bol. latinoam. Caribe plantas med. aromát ; 19(1): 142-148, ene. 2020. ilus, tab
Article in English | LILACS | ID: biblio-1103091

ABSTRACT

The research of new substances capable of controlling the Aedes aegypti mosquito is urgent due to the increase in the transmission of the diseases such as dengue, chikungunya and Zika virus by the vector. Thus, the aim of this study was to evaluate the larvicidal activity of crude extract of Piper corcovadensis roots, a native plant from Brazil, and of the isolated compound piperovatine against larvae of A. aegypti by the larval immersion test. The lethal concentration that killed 50% (LC50) and 99% (LC99) of larvae was determined by Probit analysis. The results indicated high larvicidal activity on A. aegypti larvae for crude extract of Piper corcovadensis roots with LC50 of 4.86 µg/mL and LC99 of 15.50 µg/mL and piperovatine with LC50 of 17.78 µg/mL and LC99 of 48.55 µg/mL. This work opens new perspectives to the development of future products with crude extract of Piper corcovadensis roots and piperovatine that can be applied to mosquito control.


La investigación de nuevas sustancias capaces de controlar el mosquito Aedes aegypti es urgente debido al aumento en la transmisión de enfermedades como el dengue, el chikungunya y el virus Zika por el vector. Por lo tanto, el objetivo de este estudio fue evaluar la actividad larvicida del extracto crudo de las raíces de Piper corcovadensis, una planta nativa de Brasil, y del compuesto aislado piperovatine contra larvas de A. aegypti mediante la prueba de inmersión larvaria. La concentración letal que mató al 50% (LC50) y al 99% (LC99) de larvas se determinó mediante análisis Probit. Los resultados indicaron una alta actividad larvicida en larvas de A. aegypti para extracto crudo de las raíces de Piper corcovadensis con LC50 de 4.86 µg/mL y LC99 de 15.50 µg/mL y piperovatine con LC50 de 17.78 µg/mL y LC99 de 48.55 µg/mL. Este trabajo abre nuevas perspectivas para el desarrollo de futuros productos con extracto crudo de las raíces de Piper corcovadensis y piperovatine que pueden aplicarse al control de mosquitos.


Subject(s)
Animals , Sorbic Acid/analogs & derivatives , Plant Extracts/pharmacology , Aedes/drug effects , Piper/chemistry , Insecticides/pharmacology , Sorbic Acid/isolation & purification , Sorbic Acid/pharmacology , Yellow Fever/prevention & control , Brazil , Plant Roots , Dengue/prevention & control , Larvicides , Zika Virus Infection/prevention & control , Larva/drug effects , Methylene Chloride
4.
Mem. Inst. Oswaldo Cruz ; 115: e200271, 2020. tab, graf
Article in English | LILACS, SES-SP | ID: biblio-1135271

ABSTRACT

BACKGROUND Aedes aegypti is the primary transmitter of several arbovirus with great impact in human health. Controlling vector mosquitoes is an essential and complex task. One promising control method is to use mosquitoes as a vehicle to disseminate tiny particles of juvenile-killing insecticides, such as pyriproxyfen (PPF), to breeding sites. OBJECTIVES We aimed to investigate the capacity of Ae. aegypti to disseminate two new formulations of PPF in two sites of Rio de Janeiro city for assessment of the efficacy of these products. METHODS Dissemination stations impregnated with powder and liquid new formulations of PPF were installed in two test sites. Ovitraps were used in the test sites and in a control site for monitoring the presence of Ae. aegypti throughout eggs collection. FINDINGS Entomological indices indicated that the new formulations of PPF were efficient in reducing eggs abundance. Liquid formulation performed better than powder formulation. Ready-to-use formulations of PPF can be quickly applied in the field and can be replaced after a few months. MAIN CONCLUSIONS New formulations of PPF associated with mosquito dissemination approach make a valuable vector control strategy, managing to cover places of difficult access for whatever reason. New formulations application requires less labour, being economically attractive.


Subject(s)
Humans , Animals , Adolescent , Pyridines/pharmacology , Mosquito Control/methods , Aedes/drug effects , Insecticides/pharmacology , Larva/drug effects , Cities , Mosquito Vectors/growth & development , Mosquito Vectors/drug effects , Larva/growth & development
5.
Rev. Soc. Bras. Med. Trop ; 53: e20190489, 2020. tab, graf
Article in English | LILACS | ID: biblio-1057274

ABSTRACT

Abstract INTRODUCTION: In Brasilia, pyriproxyfen (PPF; 0.01 mg/L) has been used for the larval control of Aedes aegypti mosquitoes since 2016. Information on the susceptibility of Ae. aegypti to PPF, and the development of resistance in populations from the Federal District of Brazil (FD) is limited. It is essential to monitor the susceptibility of Ae. aegypti to insecticides in order to improve vector control strategies. This study aimed to evaluate the susceptibility of Ae. aegypti populations from five areas of Brasilia to PPF. METHODS: We performed dose-response tests to estimate the emergence inhibition and resistance ratio of each field population, including the Rockefeller reference population. We also analyzed egg positivity, and the density and mortality of larvae and pupae. RESULTS: Populations from Vila Planalto (RR50=1.7), Regiment Guards Cavalry (RR50=2.5), and Sub-secretary of Justice Complex (RR50=3.7) presented high susceptibility to PPF, while the RR values of populations from Lago Norte (RR50=7.7) and Varjão (RR50=5.9) were moderately high, suggesting the emergence of insipient resistance to PPF in Brasilia. At 30 ng/mL, the highest larvae mortality rate was 2.7% for the population from Lago Norte, while that of pupae was 92.1% for Varjão and Vila Planalto. CONCLUSIONS: The five populations of Ae. aegypti from the FD are susceptible to PPF and there is a need to monitor the susceptibility of Ae. aegypti in new areas of the FD.


Subject(s)
Animals , Pyridines/pharmacology , Insecticide Resistance , Aedes/drug effects , Mosquito Vectors/drug effects , Insecticides/pharmacology , Brazil , Larva/drug effects
6.
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
7.
Mem. Inst. Oswaldo Cruz ; 115: e200313, 2020. tab, graf
Article in English | LILACS | ID: biblio-1154867

ABSTRACT

BACKGROUND Aedes aegypti is the sole vector of urban arboviruses in French Guiana. Overtime, the species has been responsible for the transmission of viruses during yellow fever, dengue, chikungunya and Zika outbreaks. Decades of vector control have produced resistant populations to deltamethrin, the sole molecule available to control adult mosquitoes in this French Territory. OBJECTIVES Our surveillance aimed to provide public health authorities with data on insecticide resistance in Ae. aegypti populations and other species of interest in French Guiana. Monitoring resistance to the insecticide used for vector control and to other molecule is a key component to develop an insecticide resistance management plan. METHODS In 2009, we started to monitor resistance phenotypes to deltamethrin and target-site mechanisms in Ae. aegypti populations across the territory using the WHO impregnated paper test and allelic discrimination assay. FINDINGS Eight years surveillance revealed well-installed resistance and the dramatic increase of alleles on the sodium voltage-gated gene, known to confer resistance to pyrethroids (PY). In addition, we observed that populations were resistant to malathion (organophosphorous, OP) and alpha-cypermethrin (PY). Some resistance was also detected to molecules from the carbamate family. Finally, those populations somehow recovered susceptibility against fenitrothion (OP). In addition, other species distributed in urban areas revealed to be also resistant to pyrethroids. CONCLUSION The resistance level can jeopardize the efficiency of chemical adult control in absence of other alternatives and conducts to strongly rely on larval control measures to reduce mosquito burden. Vector control strategies need to evolve to maintain or regain efficacy during epidemics.


Subject(s)
Animals , Pyrethrins/pharmacology , Insecticide Resistance/drug effects , Insecticide Resistance/genetics , Aedes/drug effects , Mosquito Vectors/drug effects , Insecticides/pharmacology , Mosquito Control/methods , Aedes/genetics , Spatio-Temporal Analysis , Mosquito Vectors/virology , French Guiana , Insect Vectors/drug effects , Insect Vectors/genetics
8.
Article in English | LILACS | ID: biblio-1284300

ABSTRACT

The chemical composition and larvicidal activity of essential oils derived from the leaves and rhizomes of Zingiber montanum (J. Koenig) Link ex. A. Dietr. were reported. The main compounds in the leaf oil were ß-pinene (13.8%), ß-phellandrene (11.3%) and α-pinene (7.3%) while the rhizome oil was dominated by sabinene (41.1%), terpinen-4-ol (22.7%) and (E)-nerolidol (14.3%). The minimum lethal concentration (larvicidal activity) LC50of the rhizome oil at 24 h against Aedes albopictus was 35.17 µg/mL, while LC50 values of 32.20 µg/mL and 31.12 µg/mL were obtained against Aedes aegypti and Culex quinquefasciatus respectively. At 48 h the oil displayed larvicidal action with LC50 values of 23.18 µg/mL, 25.58 µg/mL and 18.99 µg/mL respectively towards Ae. albopictus, Ae. Aegyptiand Cx. quinquefasciatus. The leaf oil did not exhibit significant mortality and larvicidal action. The results indicate the potential of rhizome essential oil of Z. montanumas a source of larvicidal agent.


En el presente trabajo se reportan la composición química y actividad larvicida de los aceites esenciales obtenidos de hojas y rizomas de Zingiber montanum (J. Koenig) Link ex. A. Dietr. Los principales compuestos en el aceite de hojas fueron ß-pineno (13.8%), ß-felandrene (11.3%) y α-pineno (7.3%); mientras que los más abundantes en el aceite de rizomas fueron sabineno (41.1%), terpinen-4-ol (22.7%) y (E)-nerolidol (14.3%). La concentración letal mínima (actividad larvicida) LC50 del aceite de riomas ante Aedes albopictus fue 35.17 µg/mL, mientras que los valores de LC50 de 32.20 µg/mL y 31.12 µg/mL fueron obtenidos ante Aedes aegyptiy Culex quinquefasciatus respectivamente. A las 48 horas, el aceite mostró acción larvicida con valores de LC50 de 23.18 µg/mL, 25.58 µg/mL y 18.99 µg/mL respectivamente, ante Ae. albopictus, Ae. Aegyptiand Cx. quinquefasciatus. El aceite de hojas no mostró mortalidad ni acción larvicida significativa. Los resultados indican el potencial del aceite esencial de rizomas de Z. montanum como una fuente de agentes larvicidas.


Subject(s)
Animals , Pesticides/pharmacology , Oils, Volatile/pharmacology , Zingiberaceae/chemistry , Culicidae/drug effects , Pesticides/chemistry , Oils, Volatile/chemistry , Analysis of Variance , Chromatography, Gas , Aedes/drug effects , Culex/drug effects , Monoterpenes/analysis , Larvicides , Mosquito Vectors
10.
Epidemiol. serv. saúde ; 28(1): e2017316, 2019. tab
Article in English, Portuguese | LILACS | ID: biblio-984375

ABSTRACT

Objetivo: avaliar, em condições simuladas de campo, a eficácia do pyriproxyfen (hormônio juvenil), do novaluron (inibidor de quitina) e do spinosad (biolarvicida) no controle do Aedes aegypti. Métodos: exposição periódica de larvas de Ae. aeypti obtidas em Itabuna a recipientes tratados com os larvicidas, e comparação do efeito residual do tratamento com cepa Rockfeller. Resultados: o efeito inibitório na emergência de adultos, após 60 dias, foi de 89,5% spinosad, 96,5% novaluron e 75,4% pyriproxifen para larvas de Itabuna, não havendo diferença estatística (p=0,412) entre os tratamentos; spinosad e novaluron apresentaram maior percentual de mortalidade na fase larval, 98,8% e 97,9% respectivamente; pyriproxifen apresentou mortalidade maior na fase pupal, 95,1%. Conclusão: os três larvicidas apresentaram controle semelhante; no entanto, o pyriproxifen pode deixar a falsa impressão de positividade dos criadouros, por agir em fase pupal, comprometendo os indicadores de infestação que são parâmetros estratégicos para as ações de controle.


Objetivo: evaluar en condiciones simuladas de campo la eficacia del piriproxifén (hormona juvenil), novaluron (inhibidor de quitina) y spinosad (biolarvicida) en el control del Ae. Aegypti. Métodos: exposición periódica de larvas obtenidas de Itabuna, BA, Brasil, a recipientes tratados con larvicida y comparación del efecto residual con cepa Rockefeller. Resultados: el efecto inhibidor en la emergencia de adultos, después de 60 días, fue de 89,5% spinosad, 96,5% novaluron y 75,4% piriproxifén para larvas de Itabuna, no habiendo diferencia estadística (p=0,412) entre los tratamientos; spinosad y novaluron presentaron mayor mortalidad en la fase larval, 98,8% y 97,9% respectivamente; piriproxifén presentó mayor mortalidad en la fase de pupa, 95,1%. Conclusión: los tres larvicidas fueron eficaces en el control de larvas de Ae. Aegypti; sin embargo, piriproxifén puede dejar falsa positividad de los criaderos, por actuar en fase de pupa, comprometiendo los indicadores de infestación, parámetros estratégicos para las acciones de control.


Objective: to evaluate, under simulated field conditions, the efficacy of pyriproxyfen (juvenile hormone), novaluron (chitin inhibitor) and spinosad (biolarvicide) in controlling Aedes aegypti. Methods: periodic exposition of Ae. aegypti larvae collected in Itabuna, BA, Brazil, to recipients treated with larvicides and comparison of residual effect of treatment with the Rockefeller strain. Results: the inhibitory effect on adult emergence after 60 days was spinosad 89.5%, novaluron 96.5% and pyriproxifen 75.4% for Itabuna larvae, with no statistical difference (p=0.412) between treatments; spinosad and novaluron had a higher percentage of mortality in the larval stage, 98.8% and 97.9% respectively; pyriproxyfen showed higher mortality (95.1%) in the pupal stage. Conclusion: the three larvicides demonstrated similar control; however, pyriprofyxen might give a false impression of breeding ground positivity as it acts at the pupal stage, compromising the indicators of infestation that are strategic parameters for control actions.


Subject(s)
Mosquito Control/methods , Epidemiology, Experimental , Aedes/growth & development , Aedes/drug effects , Larvicides , Larva/drug effects , Survival Analysis , Mosquito Vectors/growth & development , Insecticides/pharmacology , Larva/growth & development
11.
Mem. Inst. Oswaldo Cruz ; 114: e190120, 2019. tab, graf
Article in English | LILACS | ID: biblio-1040624

ABSTRACT

BACKGROUND In recent years, South America has suffered the burden of continuous high impact outbreaks of dengue, chikungunya and Zika. Aedes aegypti is the main mosquito vector of these arboviruses and its control is the only solution to reduce transmission. OBJECTIVES In order to improve vector control it is essential to study mosquito population genetics in order to better estimate the population structures and the geneflow among them. METHODS We have analysed microsatellites and knockdown resistance (kdr) mutations from a trans-border region in Amazonia between the state of Amapá (Brazil) and French Guiana (overseas territory of France), to provide further knowledge on these issues. These two countries have followed distinct vector control policies since last century. For population genetic analyses we evaluated variability in 13 well-established microsatellites loci in Ae. aegypti from French Guiana (Saint Georges and Cayenne) and Brazil (Oiapoque and Macapá). The occurrence and frequency of kdr mutations in these same populations were accessed by TaqMan genotype assays for the sites 1016 (Val/Ile) and 1534 (Phe/Cys). FINDINGS We have detected high levels of gene flow between the closest cross-border samples of Saint-Georges and Oiapoque. These results suggest one common origin of re-colonisation for the populations of French Guiana and Oiapoque in Brazil, and a different source for Macapá, more similar to the other northern Brazilian populations. Genotyping of the kdr mutations revealed distinct patterns for Cayenne and Macapá associated with their different insecticide use history, and an admixture zone between these two patterns in Saint Georges and Oiapoque, in accordance with population genetic results. MAIN CONCLUSIONS The present study highlights the need for regional-local vector surveillance and transnational collaboration between neighboring countries to assess the impact of implemented vector control strategies, promote timely actions and develop preparedness plans.


Subject(s)
Animals , Insecticide Resistance/genetics , Aedes/drug effects , Aedes/genetics , Mosquito Vectors/drug effects , Mosquito Vectors/genetics , Mutation/genetics , Brazil , Insecticide Resistance/drug effects , Biodiversity , French Guiana , Genotype
12.
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
13.
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
14.
Bol. latinoam. Caribe plantas med. aromát ; 17(3): 302-309, mayo 2018. ilus, tab
Article in English | LILACS | ID: biblio-915398

ABSTRACT

Vitex gardneriana Schauer (Lamiaceae) popularly known as "jaramataia", is a shrub commonly found in caatinga biome located in Northeast Brazil. In folk medicine, its leaves have been used as analgesic and anti-inflammatory agents. The chemical composition of the essential oil from leaves obtained by hydrodistillation was analyzed and identified by GC-MS and GC-FID and showing a total of 26 constituents (95.9%) being 2 monoterpenes (0.4%) and 24 sesquiterpenes (95.4%). The main constituents identified were cis-calamenene (29.7%), 6,9-guaiadiene (14.5%) and caryophyllene oxide (14.0%). The essential oil has been demonstrated high larvicidal activity against Aedes aegypti (LC50 = 28.0 µg/mL). In the evaluation of the bioassay with Artemia salina the essential oil showed LC50 = 98.11 µg/mL. In addition, the essential oil did not show cytotoxicity (IC50 > 2.50 mg/mL) by the hemolysis assay.


Vitex gardneriana Schauer (Lamiaceae) popularmente conocido como "jaramataia", es un arbusto que se encuentra comúnmente en el bioma de caatinga ubicado en el noreste de Brasil. En medicina popular, sus hojas se han utilizado como analgésicos y agentes antiinflamatorios. La composición química de los aceites esenciales de las hojas obtenidas por hidrodestilación fue analizada e identificada por GC-MS y GC-FID y mostrando un total de 26 constituyentes (95.9%) siendo 2 monoterpenos (0.4%) y 24 sesquiterpenos (95.4%). Los componentes principales fueron cis-calamenene (29.7%), 6,9-guaiadiene (14.5%) y caryophyllene oxide (14.0%). El aceite esencial ha demostrado una alta actividad larvicida contra Aedes aegypti (CL50 = 28.0 µg/mL). En la evaluación del bioensayo con Artemia salina, el aceite esencial demostró CL50 = 98.11 µg/mL. Además, el aceite esencial no mostró citotoxicidad (IC50 > 2.5 mg / mL) mediante el ensayo de hemólisis.


Subject(s)
Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Plant Leaves/chemistry , Aedes/drug effects , Vitex/chemistry , Terpenes/analysis , Oils, Volatile/chemistry , Plant Extracts/chemistry , Chromatography, Gas , Larvicides , Larva
15.
An. acad. bras. ciênc ; 89(1,supl): 373-382, May. 2017. tab, graf
Article in English | LILACS | ID: biblio-886653

ABSTRACT

ABSTRACT Cardanol is a constituent of Cashew Nut Shell Liquid that presents larvicidal activity against Aedes aegypti. The isolation of cardanol is somewhat troublesome, however, in this work we describe an efficient and inexpensive method to obtain it as a pure material. The compound was used as starting material to make chemical transformation leading to saturated cardanol, epoxides and, halohydrins. These derivatives were tested for toxicity against Aedes aegypti larvae. The results showed that iodohydrins are very promising compounds for making commercial products to combat the vector mosquito larvae presenting a LC50 of 0.0023 ppm after 72 h of exposure.


Subject(s)
Animals , Phenols/pharmacology , Aedes/drug effects , Insecticides/pharmacology , Phenols/isolation & purification , Phenols/toxicity , Phenols/chemistry , Time Factors , Insecticides/chemical synthesis , Insecticides/toxicity , Larva/drug effects , Lethal Dose 50
16.
An. acad. bras. ciênc ; 89(3,supl): 2273-2280, 2017. tab, graf
Article in English | LILACS | ID: biblio-886818

ABSTRACT

ABSTRACT Control strategies using insecticides are sometimes ineffective due to the resistance of the insect vectors.In this scenario new products must be proposed for the control of insect vectors.The complexes L-aspartate Cu (II) and L-glutamate-Cu (II) complexes were synthesized and characterized by elemental analysis, visible ultraviolet, infrared spectroscopy and potentiometric titration. The toxicity of these complexes was analyzed in Aedes aegypti (Diptera: Culicidae) larvae and Gram-negative and Gram-positive bacteria. The interaction between the ligands and the amino acid balance and the distribution of the species as a function of pH were discussed. The lethal concentration median (LC50) for Ae. aegypti larvae were: L-glutamic acid-Cu (II) - 53.401 mg L-1 and L-aspartate-Cu (II) - 108.647 mg L-1. The minimum inhibitory concentration (MIC) required for Staphylococcus aureus and Escherichia coli was: L-glutamate-Cu (II) 500-2000 mg L-1 and L-aspartate-Cu (II) 1000-2000 mg L-1. The concentrations demonstrated toxicity that evidence the potential of the complexes as bactericide and insecticide. Metal complexes formed by amino acids and transition metals are advantageous because of low environmental toxicity, biodegradability and low production cost.


Subject(s)
Animals , Staphylococcus aureus/drug effects , Aspartic Acid/chemistry , Glutamic Acid/chemistry , Copper/chemistry , Aedes/drug effects , Escherichia coli/drug effects , Toxicity Tests , Larva/drug effects , Lethal Dose 50
17.
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
18.
Mem. Inst. Oswaldo Cruz ; 111(5): 311-321, May 2016. tab, graf
Article in English | LILACS | ID: lil-782049

ABSTRACT

The organophosphate temephos has been the main insecticide used against larvae of the dengue and yellow fever mosquito (Aedes aegypti) in Brazil since the mid-1980s. Reports of resistance date back to 1995; however, no systematic reports of widespread temephos resistance have occurred to date. As resistance investigation is paramount for strategic decision-making by health officials, our objective here was to investigate the spatial and temporal spread of temephos resistance in Ae. aegypti in Brazil for the last 12 years using discriminating temephos concentrations and the bioassay protocols of the World Health Organization. The mortality results obtained were subjected to spatial analysis for distance interpolation using semi-variance models to generate maps that depict the spread of temephos resistance in Brazil since 1999. The problem has been expanding. Since 2002-2003, approximately half the country has exhibited mosquito populations resistant to temephos. The frequency of temephos resistance and, likely, control failures, which start when the insecticide mortality level drops below 80%, has increased even further since 2004. Few parts of Brazil are able to achieve the target 80% efficacy threshold by 2010/2011, resulting in a significant risk of control failure by temephos in most of the country. The widespread resistance to temephos in Brazilian Ae. aegypti populations greatly compromise effective mosquito control efforts using this insecticide and indicates the urgent need to identify alternative insecticides aided by the preventive elimination of potential mosquito breeding sites.


Subject(s)
Animals , Aedes/drug effects , Insect Vectors/drug effects , Insecticide Resistance , Insecticides/pharmacology , Temefos/pharmacology , Biological Assay , Brazil , Larva/drug effects , Spatio-Temporal Analysis
19.
PJMR-Pakistan Journal of Medical Research. 2016; 55 (1): 11-15
in English | IMEMR | ID: emr-179078

ABSTRACT

Background: Emergence of resistance to insecticides against mosquitoes and other disease vectors has prompted the need for alternate sources of mosquito control which are more target-specific, easily bio-degradable and effective against mosquitoes


Materials and Methods: The adulticidal efficacy of crude Neem oil extract, Pine oil extract and Til oil extract with five different concentrations i.e. 2%, 4%, 6%, and 8% was tested against five to six days old sugar fed female Aedes aegypti using standard WHO Bioassay test kit. The percentage mortality was observed after 24 and 48 hours under laboratory condition


Results: The LC[50] [Lethal Concentration] values of Neem oil extract against adults of Aedes aegypti were 1.17 ml and 0.09 ml after 24 and 48 hours of exposure respectively, while the LC[99] were 4.27 ml and 1.17 ml after 24 and 48 hours of exposure respectively. The LC[50] values of Pine oil extract after 24 and 48 hours were 0.25 and, 0.06 ml respectively, while LC[99] values at 24 and 48 hour were and 0.89 ml and 0.64 ml respectively. The LC[50] values of Til oil extract after 24 and 48 hours of exposure were 1.17 ml and 0.05 ml respectively while LC99 values were 4.18 ml and 1.28 ml after 24 and 48 hours of exposure respectively. The LC[50] and LC[90] values were indicative that the plant extracts were highly toxic after 48 hours of exposure. Among the tested plant oil extracts the maximum adulticidal efficacy was observed in the pine oil extract. No mortality was observed in controls


Conclusion: Crude extract of Pine oil was more effective against Aedes aegypti as compared to Neem and Til oil


Subject(s)
Insecta , Plant Proteins , Calcium-Binding Proteins , Pinus , Plant Extracts , Plant Oils , Aedes/drug effects
20.
Mem. Inst. Oswaldo Cruz ; 110(5): 629-635, Aug. 2015. ilus
Article in English | LILACS | ID: lil-755896

ABSTRACT

Studies evaluated the effects of hexanic extracts from the fruits and flowers ofClusia fluminensis and the main component of the flower extract, a purified benzophenone (clusianone), against Aedes aegypti. The treatment of larvae with the crude fruit or flower extracts from C. fluminensis did not affect the survival ofAe. aegypti (50 mg/L), however, the flower extracts significantly delayed development of Ae. aegypti. In contrast, the clusianone (50 mg/L) isolate from the flower extract, representing 54.85% of this sample composition, showed a highly significant inhibition of survival, killing 93.3% of the larvae and completely blocking development of Ae. aegypti. The results showed, for the first time, high activity of clusianone against Ae. aegypti that both killed and inhibited mosquito development. Therefore, clusianone has potential for development as a biopesticide for controlling insect vectors of tropical diseases. Future work will elucidate the mode of action of clusianone isolated from C. fluminensis.

.


Subject(s)
Animals , Aedes/drug effects , Clusia/chemistry , Insect Vectors/drug effects , Larva/drug effects , Plant Extracts/pharmacology , Time Factors
SELECTION OF CITATIONS
SEARCH DETAIL