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The objective of this study was to evaluate the larvicidal activity of diterpenoids obtained from the oil-resin of Copaifera reticulata against Aedes aegypti larvae, the principal vector of dengue and urban yellow fever. Four diterpenes were obtained from oil-resin extraction with organic solvents and subsequent chromatographic and spectroscopic procedures allowed to isolation and identification of these compounds as 3-b-acetoxylabdan-8(17)-13-dien-15-oic acid (1), alepterolic acid (2), 3-b-hidroxylabdan-8(17)-en-15-oic acid (3), and ent-agatic acid (4). Each compound was previously dissolved in dimethylsulphoxide, and distilled water was added to obtain the desired concentrations. Twenty larvae of third instars were placed into plastic beckers, containing the solution test (25 mL), in a five repetitions scheme, and their mortality, indicated by torpor and darkening of the cephalic capsule, was recorded after 48h. Probit analyses were used to determine lethal concentrations (LC50 and LC90) and their respective 95% confidence intervals. This study showed that only diterpenoids 1 and 2 exhibited larvicidal properties with LC50 of 0.8 ppm and 87.3 ppm, respectively, revealing the former as the most toxic compound against third instars of Ae. aegypti. Therefore, this compound seems to be an interesting source for new metabolite to be exploited.

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Suppressing mosquito populations with precision guided sterile males

Nature Communications ◽

10.1038/s41467-021-25421-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Ming Li ◽

Ting Yang ◽

Michelle Bui ◽

Stephanie Gamez ◽

Tyler Wise ◽

...

Keyword(s):

Control System ◽

Aedes Aegypti ◽

Yellow Fever ◽

Sterile Insect Technique ◽

Life Stage ◽

Molecular Genetic ◽

Control Methods ◽

Wild Populations ◽

Principal Vector ◽

Platform Technology

AbstractThe mosquito Aedes aegypti is the principal vector for arboviruses including dengue/yellow fever, chikungunya, and Zika virus, infecting hundreds of millions of people annually. Unfortunately, traditional control methodologies are insufficient, so innovative control methods are needed. To complement existing measures, here we develop a molecular genetic control system termed precision-guided sterile insect technique (pgSIT) in Aedes aegypti. PgSIT uses a simple CRISPR-based approach to generate flightless females and sterile males that are deployable at any life stage. Supported by mathematical models, we empirically demonstrate that released pgSIT males can compete, suppress, and even eliminate mosquito populations. This platform technology could be used in the field, and adapted to many vectors, for controlling wild populations to curtail disease in a safe, confinable, and reversible manner.

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Larvicidal and Enzymatic Inhibition Effects of Annona muricata Seed Extract and Main Constituent Annonacin against Aedes aegypti and Aedes albopictus (Diptera: Culicidae)

Pharmaceuticals ◽

10.3390/ph12030112 ◽

2019 ◽

Vol 12 (3) ◽

pp. 112 ◽

Cited By ~ 3

Author(s):

Rodrigues ◽

Silva ◽

Pinto ◽

Lima dos Santos ◽

Carneiro de Freitas ◽

...

Keyword(s):

Aedes Aegypti ◽

Bioactive Compounds ◽

Larvicidal Activity ◽

Aedes Albopictus ◽

New Products ◽

Seed Extract ◽

Annona Muricata ◽

Main Constituent ◽

Environmentally Sustainable ◽

Lc50 And Lc90

The mosquitoes Aedes aegypti and Aedes albopictus are vectors of arboviruses that cause dengue, zika and chikungunya. Bioactive compounds from plants are environmentally sustainable alternatives to control these vectors and thus the arboviruses transmitted by them. The present study evaluated the larvicidal activity of an acetogenin-rich fraction (ACERF) and its main constituent annonacin obtained from Annona muricata seeds on Ae. aegypti and Ae. albopictus. The larvicidal assays were performed using different concentrations to calculate the LC50 and LC90 values observed 24 h after exposure to the treatment. Annonacin was more active against Ae. aegypti (LC50 2.65 μg·mL−1) in comparison with Ae. albopictus (LC50 8.34 μg·mL−1). In contrast, the acetogenin-rich fraction was more active against Ae. albopictus (LC50 3.41 μg·mL−1) than Ae. aegypti (LC50 12.41 μg·mL−1). ACERF and annonacin treated larvae of Ae. aegypti and Ae. albopictus showed significant differences in the inhibition of their metabolic enzymes when compared to untreated larvae. The results demonstrate the relevant larvicidal action of the acetogenin-rich fraction and annonacin showing the potential to develop new products for the control of Ae. aegypti and Ae. albopictus.

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Eliminating Mosquitoes with Precision Guided Sterile Males

10.1101/2021.03.05.434167 ◽

2021 ◽

Author(s):

Ming Li ◽

Ting Yang ◽

Michelle Bui ◽

Stephanie Gamez ◽

Tyler Wise ◽

...

Keyword(s):

Control System ◽

Aedes Aegypti ◽

Yellow Fever ◽

Sterile Insect Technique ◽

Life Stage ◽

Molecular Genetic ◽

Control Methods ◽

Wild Populations ◽

Principal Vector ◽

Platform Technology

AbstractThe mosquito Aedes aegypti is the principal vector for arboviruses including dengue/yellow fever, chikungunya, and zika, infecting hundreds of millions of people annually. Unfortunately, traditional control methodologies are insufficient, so innovative control methods are needed. To complement existing measures, here we develop a molecular genetic control system termed precision guided sterile insect technique (pgSIT) in Aedes aegypti. PgSIT uses a simple CRISPR-based approach to generate sterile males that are deployable at any life stage. Supported by mathematical models, we empirically demonstrate that released pgSIT males can compete, suppress, and eliminate mosquitoes in multigenerational population cages. This platform technology could be used in the field, and adapted to many vectors, for controlling wild populations to curtail disease in a safe, confinable, and reversible manner.

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Larvicidal Activity in vivo of Ethanolic and Aqueous Extracts From Moringa (Moringa oleifera Lam.) on Aedes aegypti L. (Diptera: Culicidae)

Journal of Agricultural Science ◽

10.5539/jas.v11n8p129 ◽

2019 ◽

Vol 11 (8) ◽

pp. 129

Author(s):

Antonio Carlos Leite Alves ◽

Toshik Iarley da Silva ◽

Francisco Roberto de Azevedo ◽

Estelita Pereira Lima ◽

Renata Rocha Virgulino ◽

...

Keyword(s):

Aedes Aegypti ◽

Larvicidal Activity ◽

Moringa Oleifera ◽

Chemical Constituents ◽

Control Treatment ◽

Control Group ◽

Distilled Water ◽

Aqueous Extracts ◽

Extract Concentration

The insecticides properties of Moringa oleifera (moringa) were evaluated in Aedes aegypti larvae, throughout an entirely randomized trial, represented by ethanolic and aqueous extracts obtained from leaves, flowers, barks, seeds and moringa roots, besides the control group. Five batches of 10 in 3rd stadium larvae were distributed in distilled water, added an extract concentration of 50 mL L-1, and the control treatment (distilled water). The test reading was measured after 24, 48 and 72 hours after larvae exposure, were considered dead those who did not respond to a mechanical stimulation of a clamp. The seed ethanolic extract produced the best performance after 24 hours (34% mortality), but after 48 hours, the flower extract was the more potent (38% mortality). The largest larvicidal activity was observed with the extract concentration of 90 mL L-1. The results indicate that moringa has larvacides properties against Aedes, but its chemical constituents need to be isolated and tested separately to enhance your larvicidal activity.

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Eliminating Mosquitoes with Precision Guided Sterile Males

10.21203/rs.3.rs-367110/v1 ◽

2021 ◽

Author(s):

Ming Li ◽

Ting Yang ◽

Michelle Bui ◽

Stephanie Gamez ◽

Tyler Wise ◽

...

Keyword(s):

Control System ◽

Aedes Aegypti ◽

Yellow Fever ◽

Sterile Insect Technique ◽

Life Stage ◽

Molecular Genetic ◽

Control Methods ◽

Wild Populations ◽

Principal Vector ◽

Platform Technology

Abstract The mosquito Aedes aegypti is the principal vector for arboviruses including dengue/yellow fever, chikungunya, and zika, infecting hundreds of millions of people annually. Unfortunately, traditional control methodologies are insufficient, so innovative control methods are needed. To complement existing measures, here we develop a molecular genetic control system termed precision guided sterile insect technique (pgSIT) in Aedes aegypti. PgSIT uses a simple CRISPR-based approach to generate sterile males that are deployable at any life stage. Supported by mathematical models, we empirically demonstrate that released pgSIT males can compete, suppress, and eliminate mosquitoes in multigenerational population cages. This platform technology could be used in the field, and adapted to many vectors, for controlling wild populations to curtail disease in a safe, confinable, and reversible manner.

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Larvicidal activity of microparticles of Melissa officinalis L. essential oil (Lamiaceae) against Aedes aegypti (Diptera, Culicidae)

Research Society and Development ◽

10.33448/rsd-v10i1.11166 ◽

2021 ◽

Vol 10 (1) ◽

pp. e35710111166

Author(s):

Thércia Gabrielle Teixeira Martins ◽

Paulo Victor Serra Rosa ◽

Mariana Oliveira Arruda ◽

Andressa Almeida Santana Dias ◽

Ari Pereira de Araújo Neto ◽

...

Keyword(s):

Essential Oil ◽

Aedes Aegypti ◽

Larvicidal Activity ◽

Fourth Instar ◽

Tween 20 ◽

Distilled Water ◽

Melissa Officinalis ◽

The Face ◽

Muench Method

This study aimed to evaluate the larvicidal activity of essential oil microparticles (EO) of Melissa officinalis L. against Aedes aegypti. The leaves of M. officinalis were collected in the municipality of São José de Ribamar, Maranhão, Brazil, later dried, crushed and ground. 90g of the dried leaves were used to obtain the EO by the hydrodistillation method. For the synthesis of microencapsulated EO, 60g of sodium alginate (2.5% m/v) was added to the mixture of 15g of Tween 20 with 6g of EO. The mixture was homogenized and drips over CaCl2 5% m/v solution for the hardening of particles via crosslinking. The microparticles were washed with distilled water in filter and dried at 35ºC/24h and 15 days at tamb (30ºC). The eggs of Aedes aegypti were collected at the Federal University of Maranhão by the ovitrampas method. The larvae that hatched were fed until they reached the fourth instar. Groups of larvae (n=20) were submitted to solutions of EO and microparticles of 10-90 mg/L . After 24 h, live and dead larvae were counted and LC50 was calculated by the Reed&Muench method, using Cheng's criterion for classification of active potential. All larvae presented mortality in all concentrations tested. The LC50 obtained for the EO was 40.60 mg/L and for the microparticles 22.10 mg/L, both classified as active according to the adopted criterion, but it is observed that the microparticles increased the larvicidal potential of the EO. Through the results obtained, it is concluded that the microparticles formulated with the EO proved to be efficient in the face of the larvae of Aedes aegypti, being interesting and important in controlling and combating the mosquito that transmits dengue.

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Isolation and identification of Xenorhabdus and Photorhabdus bacteria associated with entomopathogenic nematodes and their larvicidal activity against Aedes aegypti

Parasites & Vectors ◽

10.1186/s13071-017-2383-2 ◽

2017 ◽

Vol 10 (1) ◽

Cited By ~ 12

Author(s):

Chamaiporn Fukruksa ◽

Thatcha Yimthin ◽

Manawat Suwannaroj ◽

Paramaporn Muangpat ◽

Sarunporn Tandhavanant ◽

...

Keyword(s):

Aedes Aegypti ◽

Larvicidal Activity ◽

Entomopathogenic Nematodes ◽

Isolation And Identification

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Residual Larvicidal Activity of Quinones against Aedes aegypti

Molecules ◽

10.3390/molecules25173978 ◽

2020 ◽

Vol 25 (17) ◽

pp. 3978 ◽

Cited By ~ 3

Author(s):

Raquel L. Silva ◽

Daniel P. Demarque ◽

Renata G. Dusi ◽

João Paulo B. Sousa ◽

Lorena C. Albernaz ◽

...

Keyword(s):

Aedes Aegypti ◽

Yellow Fever ◽

Larvicidal Activity ◽

Residual Effect ◽

Small Scale ◽

Limited Information ◽

Effective Measure ◽

Arboviral Diseases ◽

Effect Parameter ◽

Leading Compounds

The number of documented dengue cases has increased dramatically in recent years due to transmission through the Aedes aegypti mosquito bite. Vector control remains the most effective measure to protect against this and other arboviral diseases including Zika, chikungunya and (urban) yellow fever, with an established vaccine only available for yellow fever. Although the quinone class shows potential as leading compounds for larvicide development, limited information restricts the development of optimized structures and/or formulations. Thus, in this contribution we investigated the larvicidal and pupicidal activity of three quinone compounds isolated from a Connarus suberosus root wood ethyl acetate extract together with 28 quinones from other sources. Eight quinones demonstrated larvicidal activity, of which tectoquinone (4) proved to be the most active (LC50 1.1 µg/mL). The essential residual effect parameter of four of these quinones was evaluated in laboratory trials, with tectoquinone (4) and 2-ethylanthraquinone (7) presenting the most prolonged activity. In small-scale field residual tests, tectoquinone (4) caused 100% larvae mortality over 5 days, supporting its selection for formulation trials to develop a prototype larvicide to control Ae. aegypti.

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X.—The Natural History of Yellow Fever in Africa

Proceedings of the Royal Society of Edinburgh Section B Biology ◽

10.1017/s0080455x00001338 ◽

1969 ◽

Vol 70 (3) ◽

pp. 191-227 ◽

Cited By ~ 6

Author(s):

A. J. Haddow

Keyword(s):

Natural History ◽

Aedes Aegypti ◽

Yellow Fever ◽

Narrative Form ◽

Tropical Africa ◽

Principal Vector ◽

Vector Mosquito ◽

Natural Hosts ◽

History Of ◽

Classical Vector

SynopsisThe studies on the epidemiology of yellow fever which have been carried out in Africa in the period 1925–1966 are presented in narrative form.The original isolation of the virus is described, leading on to the survey work which showed that the infection is widespread in tropical Africa and that monkeys are very important hosts—perhaps the definitive mammalian hosts—of the virus. The discoveries of a monkey-to-man cycle in which the classical vector mosquito,Aedes aegypti, is replaced byA. simpsoniand of a monkey-to-monkey cycle, in whichA. africanusis the vector, are described.Recent epidemics are discussed, particularly that in Ethiopia, where there were about 200,000 cases, with 30,000 deaths, in the period 1960–62 and where the principal vector in the man-to-man cycle wasA. simpsoni.Work on groups of animals other than monkeys is reviewed, with particular reference to studies on the lemuroid Primates of the genusGalago, which are believed to be natural hosts of the virus. It is concluded that there are still many unknown facets in the epidemiology.

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Oviplate: A Convenient and Space-Saving Method to Perform Individual Oviposition Assays in Aedes aegypti

Insects ◽

10.3390/insects9030103 ◽

2018 ◽

Vol 9 (3) ◽

pp. 103 ◽

Cited By ~ 2

Author(s):

Rafaella Ioshino ◽

Danilo Carvalho ◽

Isabel Marques ◽

Ediane Fernandes ◽

Margareth Capurro ◽

...

Keyword(s):

Cell Culture ◽

Aedes Aegypti ◽

Filter Paper ◽

Egg Production ◽

Distilled Water ◽

Time And Space ◽

Principal Vector ◽

Space Saving ◽

Gravid Females ◽

Individual Fecundity

Aedes aegypti is the principal vector of the urban arboviruses and the blood ingestion is important to produce the eggs in this species. To analyze the egg production in Ae. aegypti, researchers frequently use small cages or Drosophila vials to collect eggs from gravid females. Although it is affordable, the setup is time- and space-consuming, mainly when many mosquitoes need to be individually analyzed. This study presents an easy, cheap, and space-saving method to perform individual oviposition assays in Ae. aegypti using cell culture plates. This new method to access fecundity rate was named “oviplate”. The oviplates are setup with 12- or 24-well plates, distilled water and filter paper and they are 78 to 88% cheaper than the traditional Drosophila vial assay, respectively. Furthermore, to allocate 72 vitellogenic females in an insectary using Drosophila vial is necessary 4100 cm3 against 1400 cm3 and 700 cm3 when using 12- and 24-well plates, respectively. No statistical differences were found between the number of eggs laid in Drosophila vials and the oviplates, validating the method. The oviplate method is an affordable, and time- and space-efficient device, and it is simpler to perform individual fecundity analyses in Ae. aegypti.

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