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1.
Tropical Biomedicine ; : 453-461, 2021.
Article in English | WPRIM | ID: wpr-906558

ABSTRACT

@# Larviciding is an effective control method in managing mosquito-borne diseases. However, most of the current larvicide formulations have raised environmental concerns due to the presence of non-biodegradable inert or carrier materials. Therefore, the utilisation of biodegradable natural cellulosic fibres has created much attention. This study aims to evaluate the application of biodegradable kenaf cellulose nanofibre (KCNF) in larvicide formulation where the larvicide, namely temephos, is impregnated onto the fibre matrix (KCNF+T). The bioefficacy of the formulation was evaluated against Aedes aegypti (A. aegypti) mosquito larvae. The presence of the temephos on the KCNF was evaluated through micromorphological analysis using a field emission scanning electron microscope (FESEM) and a transmission electron microscope (TEM), while the quantity of temephos impregnated, released, and retained on the fibres upon dispersion in water were determined using high performance liquid chromatography (HPLC). It was observed that 97% of the temephos (0.1 mg) were impregnated on the KCNF. Upon dispersion in water, 53% of the temephos were released from the KCNF+T and the retention of temephos on the KCNF+T gradually decreased to 30%, 17%, and 7% on the first, third, and fifth month, respectively. Exposure of the A. aegypti larvae to the KCNF+T at concentrations ranging between 0.006 to 0.01 mg/L was effective in killing A. aegypti larvae at 17–25 folds as compared to using the temephos without KCNF. Microscopic examination revealed the accumulation of the KCNF on the larval appendages. In conclusion, this study demonstrated that the utilisation of KCNF in pesticide formulation is an effective way of delivering the temephos to control A. aegypti mosquito larvae.

2.
Rev. Soc. Bras. Med. Trop ; 54: e00922020, 2021. tab, graf
Article in English | LILACS, ColecionaSUS, SES-SP | ID: biblio-1143892

ABSTRACT

Abstract INTRODUCTION: Despite their widespread usage, synthetic insecticides and larvicides are harmful for controlling disease-causing mosquitoes owing to the development of resistance. The leaves of Eugenia astringens, Myrrhinium atropurpureum, and Neomitranthes obscura were collected from Marambaia and Grumari restingas. The safety and larvicidal efficacy of their extracts were tested against Aedes (Stegomyia) aegypti L. and Simulium (Chirostilbia) pertinax Kollar. METHODS: The dry leaves were subjected to static maceration extraction using 90% methanol. A. aegypti and S. pertinax larvae were exposed to 7.5, 12.5, and 25.0 µL/mL of the extracts (n= 30). The larvicidal activity after 24 h and 48 h, and the mortality, were determined. The median lethal concentration (CL50) was estimated by a Finney's probit model. RESULTS: M. atropurpureum and E. astringens extracts exhibited the strongest larvicidal effects against A. aegypti. M. atropurpureum extracts (25 µL/mL) caused mortalities of over 50% and 100% after 24 h and 48 h, respectively (CL50 = 11.10 and 9.68 ppm, respectively). E. astringens extracts (25 µL/mL) caused mortalities of 50% and 63.33% after 24 h and 48 h, respectively. High concentrations of N. obscura extracts induced a maximum mortality of 46.66% in A. aegypti larvae after 48 h (CL50= 25 ppm). The larvae of S. pertinax showed 100% mortality following exposure to all the plant extracts at all the tested concentrations after 24 h. CONCLUSIONS: The extracts of M. atropurpuerum exhibited the strongest larvicidal activity against A. aegypti. The larvae of S. pertinax were sensitive to all the extracts at all the tested concentrations.


Subject(s)
Animals , Simuliidae , Aedes , Culex , Myrtaceae , Insecticides/pharmacology , Anopheles , Plant Extracts/pharmacology , Plant Leaves , Larva
3.
Rev. argent. microbiol ; 52(3): 51-60, Sept. 2020. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1340904

ABSTRACT

Abstract Leptolegnia chapmanii is pathogenic to mosquito larvae. The compatibility betweenL. chapmanii and two insect growth regulators (IGR), diflubenzuron and neem oil, was evaluated. L. chapmanii was grown on culture media containing different concentrations of eachIGR. The mycelial growth was significantly reduced with the highest concentrations of IGR(F6,98= 268, p < 0.05). However, the production of zoospores (F6,56= 0.93, p > 0.05) and the lar-val mortality of Aedes aegypti (F6,56= 0.95, p > 0.05) were not significantly different amongtreatments. Furthermore, the percentage of adult emergence in the presence of different con-centrations of diflubenzuron or a neem formulation was determined, and the pathogenic activityof zoospores was evaluated at the concentrations that inhibit the emergence at 30, 50 and 90%.The pathogenicity of zoospores was not significantly different among treatments (F6,14= 0.54,p > 0.05), and the larval mortalities were above 90% in all cases.


Resumen Leptolegnia chapmanii es un patógeno de larvas de mosquitos. Se evaluó la com-patibilidad entre L. chapmanii y dos reguladores del crecimiento de insectos (IGR, por sus siglasen inglés), diflubenzurón y aceite de neem. L. chapmanii creció en medios de cultivo con diferentes concentraciones de estos IGR. El crecimiento micelial fue menor con las concentraciones más altas (F6,98= 268; p < 0,05). No hubo diferencias significativas en la producción de zoosporas (F6,56= 0,93; p > 0,05) ni en la mortalidad de las larvas de Aedes aegypti (F6,56= 0,95; p > 0,05).Se determinó el porcentaje de emergencia de adultos en presencia de diferentes concentra-ciones de diflubenzurón o de un formulado a base del aceite de neem. También se evaluó lapatogenicidad de las zoosporas a las concentraciones de los IGR que inhibieron la emergenciadel 30, 50 y 90% de adultos. No hubo diferencias significativas en la actividad de las zoosporasal comparar los tratamientos (F6,14= 054; p > 0,05). La mortalidad de las larvas fue superior al90%.

4.
Article in English | WPRIM | ID: wpr-877058

ABSTRACT

@#Introduction: Aedes sp can transmit various diseases including dengue fever, chikungunya whose symptoms are almost similar to dengue fever. In the recent times a new case is the virus outbreak of Zika. Many efforts have been made to suppress the density of the vector populations with the control of Aedes sp mosquitoes. One of them is by using vegetable larvicides namely garlic solution (Allium sativum). Methods: This research is a pseudo experiment with posttest design with a control group. The aim of this research study is to know the effectiveness of garlic solution in killing the larva Aedes sp. This research sample is 484 tails that are bred by the researchers themselves. The concentrations used in this study were 0%, 60%, 70%, 80% and 90% with 5 repetitions. The free variable in this study is the concentration of garlic solution and the bound variable is the larva Aedes sp. Results: The results of the study using one-way ANOVA test (p = 0.001) indicate that there are differences in the larvae deaths between each concentration. Observation by using the Abbot formula at a concentration of 60% it is found to be susceptible in killing of Aedes sp larvae due to the death of larvae at 100%. Conclusion: This means there is a direct relation between the increasing concentration of garlic solution and the number of dead larvae of Aedes sp. So, garlic can be one of the alternatives in vector control that is safe for the environment.

5.
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
6.
Rev. bras. farmacogn ; 29(6): 778-784, Nov.-Dec. 2019. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1057844

ABSTRACT

ABSTRACT Lippia alba (Mill.) N.E.Br. ex Britton & P. Wilson, Verbenaceae, is considered a great source of a bioactive volatile oil. Due to the wide range of known chemotypes, its chemical analysis is very important. Among the several activities of this volatile oil, a potential larvicidal action against Culicidae species is highlighted. However, the low water miscibility of volatile oils limits their application in aqueous media. Oil in water nano-emulsions are in the spotlight of novelty to solve this main problem. Thus, the aim of the present study was to obtain this nanostructured system with L. alba volatile oil (citral chemotype) and evaluate its larvicidal activity against Aedes aegypti and Culex quinquefasciatus larvae. The major compounds were geranial (30.02%) and neral (25.26%). Low mean droplet size (117.0 ± 1.0 nm) and low polydispersity index (0.231 ± 0.004) were observed and no major changes were observed after seven days of storage. LC50 values against C. quinquefasciatus and A. aegypti third-instar larvae were respectively 38.22 and 31.02 ppm, while LC90 values were, respectively, 59.42 and 47.19 ppm. The present study makes use of a low energy, solvent-free and ecofriendly method with reduced costs. Thus, this paper contributes significantly to phyto-nanobiotechnology of larvicidal agents, opening perspectives for the utilization of L. alba volatile oil in integrated practices of vector control.

7.
Pesqui. vet. bras ; 39(11): 879-888, Nov. 2019. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1056911

ABSTRACT

Brazil has one of the largest commercial cattle herds in the world, which naturally coexist with an enormous number of parasitic species. Southern cattle tick, Rhipicephalus (Boophilus) microplus, is among these species, interfering with animal productivity and causing losses to the beef and dairy cattle sector. The use of chemical acaricides in the control of this mite has resulted in the emergence of resistant populations. In this sense, alternative control measures using plants as sources of botanical acaricides have shown to be effective. Eugenia pyriformis Cambess is a Brazilian plant with antioxidant and antimicrobial activity; however, there are no reports on its acaricidal activity in the literature. The present study aimed to evaluate the acaricidal and larvicidal potential of E. pyriformis leaf essential oil (EO) on southern cattle tick at different stages of the reproductive cycle. E. pyriformis leaves were collected and dried, and had their EO extracted by hydrodistillation (3h) using a modified Clevenger apparatus. Chemical analysis was performed by gas chromatography coupled with mass spectrometry (GC/MS), and 32 compounds belonging to the sesquiterpene class were identified: hydrocarbons (17.98%) and oxygenated forms (81.96%), with spathulenol (43.65%) and caryophyllene oxide (12.17%) as the most common. The EO was evaluated by the Adult Immersion Test at the concentrations (500.00 to 3.12mg/mL) in which the following parameters were measured: mortality of females (%), hatchability of eggs (%), and product efficiency (%). Larvae were assessed by the Larval Packet Test at concentrations ranging from 25.00 to 0.00004mg/mL. Lethal concentrations (LC) required for killing 50 and 99.9% of adult females and larvae were determined using Probit analysis. LC50 and LC99.9 of EO were 0.06 and 24.60mg/mL and 1,208.80 and 2,538mg/mL for larvae and adult females, respectively. Action of the EO in the free-living cycle of R. (B.) microplus larvae was another parameter assessed. To this end, the larvae were deposited in pots containing Brachiaria decumbens and, after migration to the leaf apex, a solution containing LC99.9 (24.60mg/mL) of the EO was sprayed. After 24h, 72.25% of the larvae had died, indicating stability of the EO when subjected to uncontrolled temperature and humidity conditions. The mechanism of action through which the EO killed the larvae and adult females was investigated by the Bioautographic Method, which showed inhibition of 3.15mg/mL of the EO on the acetylcholinesterase (AChE) enzyme. The results found in the present experiment indicate that E. pyriformis essential oil is an alternative in the control of southern cattle tick in the larval (parasitic) and free-living cycle (non-parasitic) stages under field conditions.(AU)


O Brasil dispõe de um dos maiores rebanhos bovinos comerciais do mundo, sendo natural que junto a esse rebanho, coexista uma enorme quantidade de espécies parasitárias; dentre estes o carrapato Rhipicephalus (Boophilus) microplus que interfere na produtividade animal, causando prejuízos à pecuária de corte e leite. A utilização de acaricidas químicos no controle deste ácaro tem causado o surgimento de populações resistentes e neste sentido, controles alternativos utilizando plantas como fontes de acaricidas botânicos têm se mostrado eficazes. Eugenia pyriformis Cambess é uma planta brasileira com atividades antioxidante e antimicrobiana, entretanto não há relatos da atividade acaricida. O objetivo do presente estudo consistiu na avaliação do potencial acaricida e larvicida do óleo essencial das folhas de E. pyriformis sobre o carrapato bovino nos diferentes estágios do ciclo reprodutivo. As folhas foram coletadas, secas e o OE extraído por hidrodestilação (3 horas) em aparelho Clevenger modificado. A análise química foi realizada por cromatografia gasosa acoplada à espectrometria de massas (CG/EM) sendo identificados 32 compostos, pertencentes à classe sesquiterpenos: hidrocarbonetos (17.98%) e oxigenados (81.96%); tendo como majoritários o spathulenol (43,65%) e caryophylene oxide (12,17%). O OE foi avaliado pelo teste de imersão de adultos nas concentrações (500,00 a 3,12mg/mL) onde foram mensurados os parâmetros: mortalidade das fêmeas (%), eclodibilidade dos ovos (%) e eficiência do produto (%). As larvas foram avaliadas pelo teste de imersão larval (Larval Packet Test) nas concentrações que variaram de 25,00 a 0,00004mg/mL. Foram determinadas as concentrações letais (CLs) necessárias para matar 50 e 99,9% das fêmeas adultas e das larvas utilizando a análise de Probitos. As CL50 e CL99,9 do OE foram (0,06 e 24,60mg/mL) para as larvas e (1.208,80 e 2.538mg/mL) para as fêmeas adultas, respectivamente. Outro parâmetro avaliado em nossa pesquisa foi mensurar a ação do OE no ciclo de vida livre das larvas de R.(B.) microplus; onde as larvas foram depositadas em vasos com Brachiaria decumbens e após migração destas para o ápice das folhas, foi aspergido solução contendo a CL99,9 (24,60mg/mL) do OE. Após 24 horas, 72,25% das larvas morreram indicando que houve estabilidade do OE quando submetido a condições de temperatura e umidade não controladas. O mecanismo de ação pelo qual o OE matou as larvas e fêmeas adultas foi investigado pelo método bioautográfico, indicando uma inibição de 3,15mg/mL do óleo essencial sobre a enzima acetilcolinesterase (AChE). Os resultados encontrados no presente experimento indicaram que o óleo essencial de E. pyriformis é uma alternativa no controle do carrapato bovino no estágio larval (parasitário) e no ciclo de vida livre (estágio não parasitário) em condições de campo.(AU)


Subject(s)
Animals , Cattle , Rhipicephalus , Larvicides , Acaricides , Eugenia , Anti-Infective Agents, Local/therapeutic use
8.
Article in English | WPRIM | ID: wpr-846912

ABSTRACT

Objective: To assess the chemical composition and mosquito larvicidal potentials of essential oil of wild chive (Allium schoenoprasum L.) against Anopheles stephensi. Methods: In the search for an environmentally safer alternative mosquitoes control, the larvicidal efficacy of essential oil obtained from the leaves of Allium schoenoprasum L. against Anopheles stephensi was determined. The composition of chive essential oil was analyzed by gas chromatography-mass spectrometry. Results: In toxicity assays, the essential oil demonstrated substantial larvicidal activity against larvae of Anopheles stephensi with LC50 and LC90 values of 2.60, and 7.31 ppm after 24 h of exposure, respectively. Gas chromatography-mass spectrometry analysis of chive essential oil identified 35 components representing more than 97.31% of the total essential oil. The main constituents were sulfur compounds, including diallyl trisulfide (13.72%), 2-ethyl[1,3]dithiane (8.93%), allyl methyl trisulfide (8.77%), and trimethylene trisulfide (6.64%), respectively. Conclusions: This study demonstrated that wild chive essential oil has a rich source of eco-friendly bioactive compounds for use as a mosquito larvicide. The main reason for its extraordinary properties may be related to the high percentage of sulfur compounds.

9.
Article in English | WPRIM | ID: wpr-846883

ABSTRACT

Objective: To investigate the phytochemical, antioxidant and larvicidal property of Cynodon dactylon, Clerodendrum viscosum, Spilanthes acmella and Terminalia chebula against Aedes aegypti. Methods: Antioxidant capacity of methanolic extract of the plants was studied by 2,2- Diphenyl-1-picryl-hydrazyl-hydrate (DPPH) assay, ferric reducing antioxidant power assay, 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate) assay (ABTS), thiobarbituric acid reactive substance (TBARS) assay, superoxide anion scavenging activity and total antioxidant activity assay following standard protocol. Total phenolic content, total flavonoid content, carbohydrate, and plant protein were also estimated following standard protocols. Larvicidal property of plant extracts were determined following World Health Organization standard protocol. Additionally, glutathione-s-transferase (GST) and acetylcholinesterase (AchE) inhibitory property was also tested biochemically. Results: Phytochemically, high protein, carbohydrate and phenolic were found in Terminalia chebula, while Cynodon dactylon showed high flavonoid contents. Similarly, high antioxidant activity was found in Terminalia chebula with IC50 values at 13.7, 2.9, 45.2 and 46.0 μg/mL in DPPH, ABTS, TBARS and superoxide anion scavenging activity, respectively. Larvicidal study showed strongest activity in Spilanthes acmella followed by Cynodon dactylon, and Clerodendrum viscosum and Terminalia chebula. GST and AchE of Aedes aegypti larvae showed reduced enzyme activity when pre-incubated with Cynadon dactylon and Spilanthes acmella. Conclusions: The methanolic crude extracts of Cynodon dactylon, Clerodendrum viscosum, Spilanthes acmella and Terminalia chebula possess strong antioxidant and larvicidal property against Aedes aegypti and therefore, may be further investigated for the molecular mode of action.

10.
Rev. bras. farmacogn ; 28(5): 618-625, Sept.-Oct. 2018. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-977723

ABSTRACT

Abstract Aedes aegypti (Diptera: Culicidae) is the main vector of some neglected diseases, including dengue. It is very important to develop formulations that increase effectiveness of vector control with low toxicity. Quercetin is a plant-derived flavonoid that modulates the development of some insects. The low water solubility of quercetin impairs the development of water-dispersible commercial products. To circumvent this problem, the preparation of nanoformulations is considered promising. Thus, this study aimed to evaluate the effect of bulk and quercetin nanosuspension against A. aegypti larvae and also to investigate their ecotoxicity. Quercetin nanosuspension was produced by a solvent displacement method followed by solvent evaporation and was maintained in two different temperatures (4 and 25 ºC). Its size distribution and zeta potential were monitored along 30 days. The influence of quercetin nanosuspension and bulk-quercetin was investigated at various concentrations against A. aegypti and the green algae Chlorella vulgaris. The quercetin nanosuspension presented higher stability at 4 ºC and negative zeta potential values. Quercetin nanosuspension and bulk-quercetin adversely affected the larvae development, especially at the highest concentrations. Larvae mortality was between 44% and 100% (48 h) for quercetin nanosuspension at 100 and 500 ppm, respectively. The bulk-quercetin induced around 50% mortality regardless the concentration used at this same time-period. Absence of emerging mosquitoes from water was observed on the survival larvae of all the treated groups. Quercetin nanosuspension was less toxic than bulk-quercetin against C. vulgaris, especially at higher concentrations. These data indicate that quercetin nanosuspension may represent a potential larvicide for A. aegypti control, once they induced larvae death and inhibited the survival ones to emerge from water. In addition, it did not demonstrated ecotoxicity against a non-target organism, highlighting its better properties, when compared to the bulk-quercetin.

11.
Mundo saúde (Impr.) ; 42(2): 534-547, jun. 2018. ilus, tab, graf
Article in English, Portuguese | LILACS | ID: biblio-1000088

ABSTRACT

Anisakid nematode helminths have great importance in public health, with several reports of human infections causedby larvae of these parasites in several countries of the world. These parasites are common in freshwater and marine fish,with man as an accidental host. Contamination occurs when humans feed on raw fish in the form of sushi, sashimi, andceviche, which are infected by the larval stages of these nematodes. In Brazilian rivers there are records of these larvaein Astyanax altiparanae (lambaris) and Geophagus brasiliensis (pearl cichlid), which are species widely distributed in theNeotropical region, especially in Brazil. These diseases are little-known by Brazilian health professionals because theirfrequency is still low, mainly due to the population's low fish consumption and the difficulties medical professionals havein diagnosing them. The present study aimed to evaluate the larvicidal action of ginger essential oil (Zingiber officinale) onlarvae of Contracaecum sp. removed from the visceral cavity of pearl cichlid and lambaris collected from the lake at IngáPark, Maringá, PR, in the year 2016. Two hundred and thirty-four fish specimens were necropsied, and their larvae weretested to verify the larvicidal effect of ginger. Of these fish, 123 were parasitized, equivalent to 52.5%, of which 181 larvaewere collected, all from the coelomic cavity. Ginger essential oil proved to be a promising larvicide, promoting larvaldeath in vitro. This larvicidal action was observed at different times and concentrations, showing the efficacy of ginger oilin combating this zoonosis. It is suggested that new natural products be tested for this purpose, as the number of peoplewho consume raw fish in Brazil continues to increase


Os helmintos nematoides anisaquídeos possuem grande importância em saúde pública, havendo vários relatos deinfecções humanas causadas pelas larvas desses parasitos em vários países do mundo. Esses parasitas são comuns empeixes de água doce e marinhos, tendo o homem como hospedeiro acidental. A contaminação ocorre quando os sereshumanos se alimentam de peixes crus na forma de sushi, sashimi e ceviche, infectados pelos estados larvais dessesnematoides. Nos rios brasileiros há registros dessas larvas em Astyanax altiparanae (lambaris) e Geophagus brasiliensis(acará ou papa-terra), que são espécies amplamente distribuídas na região Neotropical, em especial no Brasil. Essasdoenças são pouco conhecidas pelos profissionais da saúde brasileiros, pois sua frequência ainda é pequena, devido aobaixo consumo de peixes pela população e às dificuldades no diagnóstico pela classe médica. O presente estudo tevecomo objetivo avaliar a ação larvicida do óleo essencial de gengibre (Zingiber officinale) em larvas de Contracaecumsp. retirados da cavidade visceral de acarás e lambaris, coletados no lago do Parque do Ingá, Maringá, PR no ano de2016. Nesse sentido, 234 espécimes de peixes foram necropsiados e suas larvas testadas para verificar o efeito larvicidado gengibre. Destes peixes, 123 estavam parasitados, equivalendo a 52,5%, dos quais coletou-se 181 larvas, todas nacavidade celomática. Essas substancias mostraram-se promissores larvicidas, promovendo a morte das larvas no teste invitro do óleo essencial do gengibre. Essa ação larvicida foi observada em tempos e concentrações diferentes, mostrandoa eficácia do óleo de gengibre no combate a essa zoonose. Sugere-se que novos produtos naturais sejam testados comesse objetivo, pois é crescente o aumento no número de pessoas que passaram a se alimentar de peixes crus no Brasil


Subject(s)
Humans , Zoonoses , Ginger , Fishes , Larvicides
12.
Article in Chinese | WPRIM | ID: wpr-700119

ABSTRACT

Objective: To evaluate larvicidal, pupicidal and oviposition deterrent activities of four plant essential oils from Alpinia galanga (L.) Willd rhizome, Anethum graveolens L. (An. graveolens)fruit, Foeniculum vulgare Mill. fruit, and Pimpinella anisum L. fruit against Aedes aegypti (Ae. aegypti). Methods: Four essential oils at 1%, 5% and 10% concentrations were assessed for insecticidal activity against larvae and pupae of Ae. aegypti, following the procedure of a dipping method assay. Oviposition deterrent activity of four essential oils was evaluated on gravid female of Ae. aegypti by a dual-choice oviposition bioassay. Results: The results revealed that An. graveolens oil provided the strongest larvicidal activity against Ae. aegypti among four tested plant essential oils with the highest mortality rate of 100% and LC50 value of -0.3%. From the pupicidal experiment, An. graveolens also showed the highest toxicity against Ae. aegypti pupae with the highest mortality rate of 100% at 72 h and LC50 value of 2.9%. In addition, 10% An. graveolens had an oviposition deterrent effect against Ae. aegypti with effective repellency of 100% and an oviposition activity index of –1.0. Conclusions: An. graveolens oil has a good potential as a larvicidal, pupicidal and oviposition deterrent agent for controlling Ae. aegypti.

13.
Article in English | WPRIM | ID: wpr-825779

ABSTRACT

Objective:To evaluate the toxicity against house fly Musca domestica L. (M. domestica)-larvicidal, pupicidal, and oviposition deterrent activities of essential oils (EOs) from five plants: Anethum graveolens L. (A. graveolens), Centratherum anthelminticum L. (C. anthelminticum), Foeniculum vulgare Mill. (F. vulgare), Pimpinella anisum L. (P. anisum), and Trachyspermum ammi L. (T. ammi) Sprague.Methods:Dipping, topical and dual-choice assays were performed by using each EO at three concentrations (1%, 5% and 10%) as well as cypermethrin (positive control) and ethyl alcohol (negative control) in order to determine their larvicidal, pupicidal and oviposition deterrent activities against M. domestica mortality rate and morphogenic abnormality of larvae and pupae were recorded after 3 and 10 days of incubation. Oviposition deterrent activity was recorded for 5 consecutive days from the beginning of the assay.Results:All EOs at the highest concentration (10%) were highly effective in oviposition deterrent with 100% effective repellency and an oviposition activity index of -1.00. Ten percent of F. vulgare oil exhibited the highest efficacy against the larvae with 89.6% mortality rate at 3 days and an LCConclusions:These results indicate that F. vulgare, A. graveolens and T. ammi EOs are effective larvicidal, pupicidal and oviposition deterrent agents against house fly M. domestica.

14.
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
15.
Article in Chinese | WPRIM | ID: wpr-664277

ABSTRACT

Objective:To evaluate adulticidal,larvicidal and oviposition deterrent response of the essential oil from dried Zanthoxylum limonella (Z.limonella) fruit against Aedes aegypti (Ae.aegypti) and Culex quinquefasciatus (Cx.quinquefasciatus).Methods:Z.limonella oil was tested by biological assays at 1%,5% and 10% concentrations in ethanol.Adulticidal efficacy was tested against the 2-3 day old adult females.Larvicidal activity was tested against immature stage of mosquitoes.Oviposition deterrence of the oil was evaluated on gravid females.Results:The adult mortality was observed after 24 h with the LC5o of 6.0% for Ae.aegypti,and 5.7% for Cx.quinquefasciatus.Larvicidal bioassay was carried out with the 10% Z.limonella oil against immature stages of Ae.aegypti and Cx.quinquefasciatus,which caused 100% mortality after 12 h and 24 h.In the larvicidal experiment,Z.limonella showed effective result at 1%,5% and 10% concentrations with the values of LT5o Ae.aegypti =9.78,5.61,0.24 h for larvae and LT5o =64.08,21.23 h for pupae;Cx.quinquefasciatus had LT50 =28.46,20.25,1.01 h for larvae and LT50 =67.52,27.96,4.11 h for pupae,respectively.Oviposition deterrence of the oil was evaluated on gravid females.In the study,10% Z.limonella showed 100% repellency for Ae.aegypti and 99.53% for Cx.quinquefasciatus.Likewise,oviposition activity indexes of these oil concentrations were all negative values ranging from-0.89 to-1.00 for Ae.aegypti and-0.64 to-0.99 for Cx.quinquefasciatus.The oviposition activity indexes values revealed that Z.limonella oil has deterrent effect,and it caused a remarkable negative response resulting in very few eggs.Conclusions:This result indicates that Z.limonella oil can be used as an effective adulticide,larvicide and oviposition deterrent against Ae.aegypti and Cx.quinquefasciatus.

16.
Article in Chinese | WPRIM | ID: wpr-511488

ABSTRACT

Objective: To evaluate the larvicidal activity of the ethanolic and aqueous extracts of the endocarp and seeds of Dracaena loureiri (D. loureiri) against the dengue mosquito vector, Aedes aegypti. Methods: Bioassays were performed by exposing late third-stage to early fourth-stage larvae of Aedes aegypti to various concentrations of the extracts from D. loureiri. The larval mortality was observed after 24-and 48-h exposure. Results: The larvicidal bioassay in this study demonstrated that the ethanolic endocarp extract was the most effective with the LC50 value of 84.00 mg/L after 24 h exposure and< 50 mg/L after 48 h exposure. Extracts from the other parts of the plant were signifi-cantly less effective as a larvicide. Conclusions: The ethanolic endocarp extract of D. loureiri demonstrated effective lar-vicidal activity. It is an alternative source for developing a novel larvicide for controlling this mosquito species.

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(7): 443-449, tab, graf
Article in English | LILACS | ID: lil-787552

ABSTRACT

Environmentally friendly botanical larvicides are commonly considered as an alternative to synthetic larvicides against Aedes aegypti Linn. In addition, mosquito resistance to currently used larvicides has motivated research to find new compounds acting via different mechanisms of action, with the goal of controlling the spread of mosquitos. Essential oils have been widely studied for this purpose. This work aims to evaluate the larvicidal potential of Syzygium aromaticum and Citrus sinensis essential oils, either alone or in combination with temephos, on Ae. aegypti populations having different levels of organophosphate resistance. The 50% lethal concentration (LC50) of the essential oils alone and in combination with temephos and the influence of essential oils on vector oviposition were evaluated. The results revealed that essential oils exhibited similar larvicidal activity in resistant populations and susceptible populations. However, S. aromaticum and C. sinensis essential oils in combination with temephos did not decrease resistance profiles. The presence of the evaluated essential oils in oviposition sites significantly decreased the number of eggs compared to sites with tap water. Therefore, the evaluated essential oils are suitable for use in mosquito resistance management, whereas their combinations with temephos are not recommended. Additionally, repellency should be considered during formulation development to avoid mosquito deterrence.


Subject(s)
Animals , Aedes , Citrus sinensis/chemistry , Insecticides , Oils, Volatile , Syzygium/chemistry , Temefos , Drug Combinations , Insecticide Resistance/drug effects , Larva/drug effects , Mosquito Control/methods , Oviposition/drug effects , Reproducibility of Results , Time Factors
19.
Rev. bras. plantas med ; 18(1): 19-26, jan.-mar. 2016. tab, graf
Article in Portuguese | LILACS | ID: lil-780042

ABSTRACT

RESUMO A dengue está entre as doenças virais de propagação vetorial mais importante no mundo, causando sérios impactos de morbidade e mortalidade. Desta forma, o presente trabalho teve como objetivo analisar a composição química e a toxicidade do óleo essencial de Myrcia sylvatica (G. Mey) D.C. frente Aedes aegypti e Artemia salina. Folhas de M. sylvatica foram coletadas no Parque Nacional da Chapada das Mesas, no município de Carolina (MA) no mês de fevereiro de 2012. O óleo foi obtido por hidrodestilação e sua composição química foi determinada por cromatografia gasosa acoplada à espectrometria de massa (CG/EM). O bioensaio frente Artemia salina e às larvas de 3° estádio de Aedes aegypti foram realizados em diferentes concentrações. Os dados de mortalidade foram avaliados por regressão linear para determinar os valores de CL50. Obteve-se 0,5% de rendimento, sendo o (E)-cariofileno o constituinte majoritário. O óleo essencial apresentou uma CL50 = 79,44 µg/mL frente A. salina, sendo considerado altamente tóxico. No entanto, este óleo não demonstrou efeito sobre as larvas de A. aegypti. Considerando que o teste de Artemia salina tem correlação com atividades biológicas de grande interesse terapêutico como antitumoral, o óleo essencial das folhas de M. sylvatica demonstrou potencial para desenvolvimento de produtos farmacêuticos.


ABSTRACT Dengue is among the most important viral diseases of vector spread in the world, causing serious impacts of morbidity and mortality. Thus, this study aimed to analyze the chemical composition and toxicity of the Myrcia sylvatica (G. Mey.) DC essential oil against Aedes aegypti and Artemia salina Leach. Leaves of M. sylvatica. were collected in the Tables Chapada National Park, in the municipality of Carolina (MA) in february 2012. The oil was obtained by hydrodistillation and their chemical composition was determined by GC / MS. The bioassay front and Artemia salina larvae of the 3° stage of Aedes aegypti were performed at different concentrations. Mortality data were evaluated by linear regression to determine the LC50. Was obtained 0.5% yield values, and (E) -caryophyllene the major constituent. The essential oil showed a LC50 = 79.44 mg / mL front A. saline and is considered highly toxic. However, this oil showed no effect on larvae of A. aegypti. Whereas the brine shrimp test has regard to several biological activities, as antitumoral property, the essential oil from the leaves of M. sylvatica demonstrated potential for development of medicines.


Subject(s)
Chemistry , Toxicity , Aedes/classification , Myrtaceae/chemistry , Oils, Volatile/chemistry , Artemia/classification , Larvicides
20.
Article in Chinese | WPRIM | ID: wpr-500372

ABSTRACT

Objective: To elucidate the larvicidal potency of neem, chinaberry and Bacillus thur-ingiensis israelensis (Bti) to larvae of Anopheles arabiensis under semi-field condition and adult susceptibility/resistance to the conventionally used insecticides in Tolay, Southwestern Ethiopia. Methods: Wild collected 3rd and 4th stage larvae were exposed to neem, and chinaberry seed powder dissolved in water and Bti in artificial containers at three treatment levels:0.2, 0.1 and 0.05 g/m2 and controls were free of treatments. Larval and pupal mortalities were monitored daily and residual activities were determined. The experiments were replicated three times. The World Health Organization tube test for all classes of in-secticides was conducted on adult Anopheles arabiensis reared from field collected larvae and pupae. Data were analyzed using STATA software version 11. Results: In the first application, neem powder caused 88.9%, 87.9%and 79.4%larval and pupal mortality at 0.2, 0.1 and 0.05 g/m2 after 4.3, 6.0 and 5.7 days, respectively. The cor-responding killing effect of chinaberry was 80.3%, 62.1%and 30.3%after 7.0, 7.7 and 8.3 days respectively. Bti at all treatments killed 100%after 24 h except 2.7 days for 0.05 g/m2. Adult mosquitoes were susceptible only for fenitrothion and pirimiphos-methyl with 100%mortality while resistant to deltamethrin, alpha-cypermethrin, etofenprox and dichloro-diphenyl-tricgloroethane with only 9.0%, 3.0%, 5.1%and 2.0%mortalities respectively. Conclusions: Neem, chinaberry and Bti showed potent larvicidal and pupicidal activ-ities. However, in the area, high level of mosquito resistance to pyrethroids and dichloro-diphenyl-tricgloroethane was seen which will pose serious challenge to vector control in the future. Therefore, using integrated approach including these botanical larvicides is warranted to manage insecticide resistance.

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