Chemical Larvicides Research Articles

Seasonal insights for integrative mosquito management from multi-year baseline entomological data on Aedes aegypti in Lee County, Florida.

The spread of arboviruses like yellow fever, dengue, chikungunya, and Zika, transmitted by the invasive mosquito Aedes aegypti has led to the development of many strategies to suppress mosquito populations. Given the rapid development of resistance to common chemical larvicides and adulticides in some Ae. aegypti populations, as well as the ever-shrinking chemical options for mosquito control, there is a pressing need for new tools and deployment of those innovative tools as a component of integrative mosquito management programs. Prior to the adoption of any mosquito population intervention, be it conventional or innovative, understanding the baseline population is essential to evaluate the efficacy of the control measure. The Lee County Mosquito Control District in Florida has collected a three-year-long period of baseline entomological surveillance data collection for Ae. aegypti on Captiva and Sanibel Islands as foundational information prior to implementation of a new integrative mosquito management approach. We identified 18 mosquito species and described their population dynamics during the rainy and dry seasons. The two islands had no significant differences in species richness, diversity, dominance, or evenness overall. Yet, there were clear differences between the high rain season and low rain season in the Shannon diversity index, Simpson dominance index, and Pielou species evenness index within each site. Our data suggest that any innovative intervention should begin before mid to late April when the mosquito population is at its lowest and certainly before populations build up to their summer peak between June and September. These data also show the spatial distribution of Ae. aegypti is dynamic in space and time, identifying hotspots of mosquito abundance to focus on for future interventions. Overall, our study emphasizes the importance of entomological data collection to understand the population dynamics of Ae. aegypti mosquitoes, including the impact of environmental factors such as temperature and precipitation.

Synergistic Larvicidal and Pupicidal Toxicity and the Morphological Impact of the Dengue Vector (Aedes aegypti) Induced by Geranial and trans-Cinnamaldehyde.

Monoterpenes are effective and eco-friendly alternatives to conventional chemical larvicides. We tested single and binary mixtures of monoterpenes-geranial and trans-cinnamaldehyde-for their larvicidal and pupicidal activities against Aedes aegypti L. and for non-target toxicity on guppies (Poecilia reticulata Peters), using 1% (w/w) temephos as a reference. Geranial and trans-cinnamaldehyde at 250 ppm showed stronger larvicidal and pupicidal activities with a 100% mortality rate and an LT50 ranging from 0.3 to 0.6 h. All combinations were strongly synergistic against larvae and pupae compared to single formulations, with an increased mortality value (IMV) of 6% to 93%. The combination of geranial + trans-cinnamaldehyde (1:1) at 200 ppm showed the highest impact, with an IMV of 93%. The strongest larvicidal and pupicidal activities, a 100% mortality rate, and an LT50 of 0.2 h were achieved by geranial + trans-cinnamaldehyde (1:1) 500 ppm. They were thirty times more effective than a 1% temephos solution (LT50 ranging from 6.7 to 96 h) and caused obviously shriveled cuticles and a swollen respiratory system. All single and binary mixtures were not toxic to the guppies. Thus, the combination of geranial + trans-cinnamaldehyde has great potential as a safe insecticide for controlling mosquito larvae and pupae.

Effectiveness of mass trapping interventions using autocidal gravid ovitraps (AGO) for the control of the dengue vector, Aedes (Stegomyia) aegypti, in Northern Mexico

BackgroundMosquito-borne diseases, such as malaria, dengue, Zika and chikungunya, pose significant public health threats in tropical and subtropical regions worldwide. To mitigate the impact of these diseases on human health, effective vector surveillance and control strategies are necessary. Traditional vector control methods, which rely on chemical agents such as insecticides and larvicides, face challenges such as resistance and environmental concerns. Consequently, there has been a push to explore novel surveillance and control tools. Mass trapping interventions have emerged as a promising and environmentally friendly approach to reducing the burden of mosquito-borne diseases. This study assessed mass-trapping interventions using autocidal gravid ovitraps (AGOs) on Aedes aegypti populations in Reynosa, Tamaulipas, Mexico.MethodsFour neighborhoods were selected to evaluate the effects of three treatments: AGO mass-trapping, integrated vector control (IVC), which included source reduction and the application of chemical larvicide and adulticide, and AGO + IVC on Ae. aegypti populations. A control area with no interventions was also included.The effectiveness of the interventions was evaluated by comparing Ae. aegypti abundance between the pre-treatment period (9 weeks) and the post-treatment period (11 weeks) for each treatment.ResultsOnly treatment using AGO mass trapping with an 84% coverage significantly reduced Ae. aegypti female populations by 47%, from 3.75 ± 0.32 to 1.96 ± 0.15 females/trap/week. As expected, the abundance of Ae. aegypti in the control area did not differ from the pre- and post-treatment period (range of 4.97 ± 0.59 to 5.78 ± 0.53); Ae. aegypti abundance in the IVC treatment was 3.47 ± 0.30 before and 4.13 ± 0.35 after, which was not significantly different. However, Ae. aegypti abundance in the AGO + IVC treatment increased from 1.43 ± 0.21 before to 2.11 ± 0.20 after interventions; this increase may be explained in part by the low AGO (56%) coverage.ConclusionsThis is the first report to our knowledge on the effectiveness of mass-trapping interventions with AGOs in Mexico, establishing AGOs as a potential tool for controlling Ae. aegypti in Northeastern Mexico when deployed with sufficient coverage.Graphical

Test the Effectiveness of Soursop Leaf Extract and Tapak Dara Leaf Extract as Mosquito Larvicide

In this rainy season the risk of contracting Dengue Fever increases. Many people control dengue fever chemically. The use of chemical larvicides has many disadvantages such as environmental pollution, resistance, and negative impacts on human health. This research aims to develop a natural larvicide from extracts of soursop leaves (Annona muricata) and tapak dara leaves (Catharanthus roseus). The study used a completely randomized design, with three replications. Soursop leaf and tapak dara leaf extracts were extracted using a maceration process using 70% ethanol solvent. III-IV instar Aedes aegypti mosquito larvae were used during the experiment, to assess the effect of formula (3 levels), dose (3 levels), and exposure time for 12 hours. All data were analyzed using Two-way ANOVA. The research results showed that the F1 formula and D3 dose were effective in eradicating mosquito larvae. Where the higher the concentration of soursop leaf extract and the higher the dose, the higher the mortality of mosquito larvae.

Larvicidal Activity of Red Betel Leaves (Piper ornatum) Ethanolic Extract Against Mosquito Larvae

Larvae are the initial carriers of dengue hemorrhagic fever (DHF) and culex, making them significant in disease transmission. Excessive chemical larvicides pose serious risks to human health, thus driving the development of biological alternatives like red betel leaf extract. This study aimed to assess the efficacy of red betel leaf extract in larval control. Using 300 larvae, concentrations of 5%, 6%, and 7% were tested with three replicates over 24 h. The bioassay involved placing the larvae into a plastic container filled with the extract. It was found that ethanol extract from Piper ornatum leaves contained alkaloids, tannins, saponins, flavonoids, and terpenoids. After 24 h, results revealed 83% mortality at 5%, 98% at 6%, and 100% at 7% of extract concentration. Consequently, the 7% concentration showed the fastest efficacy in killing mosquito larvae (100% in 50 min). The LC50 value, representing the concentration at which 50% of larvae are killed, was determined to be 0.04%. Additionally, the LT50 value, indicating the time required to kill 50% of larvae (based on the LC50 value), was found to be 3.34 hours. In conclusion, red betel leaf extract demonstrated promising larvicidal activity against mosquito larvae. Future research is anticipated to prove its safety via in vitro and in vivo test.

Test The Effectiveness Of Japanese Papaya Leaf Extract (Cnidoscolus aconitifolius) On Aedes aegypti Larvae Mortality

Dengue hemorrhagic fever (DHF) is caused by the dengue virus which is transmitted through the bite of the Aedes aegypti mosquito. Prevention of DHF can be done by using larvicides. Synthetic chemical larvicides are considered to have side effects in long-term use and can cause environmental pollution. So we need an alternative larvicides with natural ingredients from plants, namely Japanese Papaya plants. This study aims to determine the effectiveness of Japanese Papaya (Cnidoscolus aconitifolius) leaf extract on the mortality of Aedes aegypti larvae. This type of research uses an experimental study design. This study used 6 treatments with 4 repetitions consisting of control without treatment, P1 (0.2%), P2 (0.4%), P3 (0.6%), P4 (0.8%), and P5 (1%). Observations were made for 48 hours. From the research results obtained LC50 of 1.095%. The results of statistical tests using One-Way ANOVA showed that there was a significant effect on the mortality of mosquito larvae.

The Differences in Toxicity of Pletekan Leaf Extracts (Ruellia tuberosa L.) and Lime (Citrus auraiflia) on Mortality of Culex sp. Mosquito Larvae

Mosquitoes Culex sp. is the main vector of filariasis. Population control using chemical larvicides continuously can cause resistance. The leaves of the pletekan plant (Ruellia tuberosa L.) and lime fruit (Citrus aurantifolia) have the potential as natural larvicides. This study aims to determine the differences in high toxicity (LC50) of pletekan leaf extract and lime fruit on the mortality of Culex sp. mosquito larvae with an exposure time of 24 hours. Pletekan leaf extract and lime fruit were extracted by maceration using 97% ethanol. The LC50 can use probit analysis with SPSS applications. The results showed that pletekan leaves were toxic to Culex sp. mosquito larvae with an LC50 value of 710.169 ppm with the lowest concentration of 615.231 ppm and the highest concentration of 796.157 ppm. The LC50 value of lime fruit extract was 1026.749 ppm, with a lower limit of 846.406 ppm and an upper limit of 1294.531 ppm.

Development of Aedes aegypti L. under the action of light radiation at different wavelengths

Aedes aegypti is a holometabolous insect, vector of medical importance for arboviral transmission, and has shown the ability to develop chemical larvicides resistance, which are the worldwide used to control mosquitoes’ population because of their low cost. Due to the well-known photophobia, a striking characteristic of the behavior of A. aegypti larvae, this study aimed to observe the development of this insect in its larval stage under the action of certain ranges of light radiation and its possible biological effects. For that, the experiments used larvae in L1, observed during seven days under the action of LEDs (light-emitting diode) that emitted light at different wavelengths, with six different colors, one for each experiment. Some were tested with a light-dark interval every 10 minutes and others every two minutes, with three repetitions. At the end, mosquitoes, pupae and larvae were counted and the data submitted to statistical evaluation. The experiment showed a significant difference between the control and the different wavelengths used, when exposed at two-minute intervals. LEDs that emitted blue (λ = 457.9 nm) and white (λ = 448.58 nm) wave frequencies were the most promising for the development of equipment that could act synergistically with other forms of control in order to improve its efficiency.

Mapping the Malaria Receptivity Area in Biak Regency, Papua Province

Malaria is an infectious disease caused by the protozoan parasite of the genus Plasmodium. This disease is transmitted through the bite of the Anopheles mosquito. Malaria is found in almost all parts of the world,According to data from the Ministry of Health, the incidence of malaria in Papua is 64,030 per 1,000 population. The purpose of this study was to determine the malaria receptive area in Biak Regency. The working area of the Bosnik Health Center and the Marauw Health Center. The material used in this study is the Larvae Entomology Survey Kit, the method used in this study is the Observational Survey of Anopheles Sp. The results of this study were from 8 breeding place points conducted by a larval survey, 2 positive points of Anopheles Sp larvae were found which were located in 2 villages, namely Orwer Village and Marauw Saba Village, Biak Regency, Papua Province. Anopheles Sp larvae were still found in Orwer and Saba villages and were included in the Malaria Receptive Area Category.It is necessary to prevent and control malaria vectors in the work area of the Biak Numfor District Health Office, both physically (pond stockpiling/sanitation engineering), chemical (insecticide and larvicide administration) and biologically (sowing fish as natural predators of Anopheles Sp larvae).

Uji Efektivitas Larvasida Ekstrak Daun Pegagan (Centella asiatica L. Urban) Terhadap Larva Culex quinquefasciatus

Culex quinquefasciatus is a vector of filariasis (elephantiasis) and Japanese encephalitis. Filariasis is still an unresolved disease in Indonesia. The use of temephos as a chemical larvicide repeatedly causes environmental pollution and is difficult to decompose, so the World Health Organization recommends looking for alternative effects. Gotu kola leaf extract contains metabolic substances such as steroids,saponins, flavonoids, phenolics that can be used as larvicides. This study aimed to determine the effectiveness of the larvicide extract of pegagan (Centella asiatica L. Urban) on the mortality of Culex quinquefasciatus larvae. This study used an experimental research design with a posttest only control group design using 4 concentration groups and 2 control groups, consisting of 4 repetitions in each, namely concentrations of 125 ppm, 250 ppm, 500 ppm, 1000 ppm, abate positive control and aquadest negative control. with the mean larval mortality was 31%, 65%, 81%, 98% which was observed for 48 hours. The number of larval deaths was analyzed using the Kruskall-Wallis test and logit analysis. The results of the analysis showed that pegagan leaf extract had an effect on the mortality of Culex quinquefasciatus larvae with a significant value (p < 0.05), then the results of logit regression analysis showed the LC50 value of 206.71 ppm. The conclusion of this study was that the leaf extract of pegagan (Centella asiatica L. Urban) was effective against the mortality of Culex quinquefasciatus larvae.

Uji Efektivitas Larvasida Ekstrak Daun Pegagan (Centella asiatica L. Urban) Terhadap Larva Culex quinquefasciatus

Culex quinquefasciatus is a vector of filariasis (elephantiasis) and Japanese encephalitis. Filariasis is still an unresolved disease in Indonesia. The use of temephos as a chemical larvicide repeatedly causes environmental pollution and is difficult to decompose, so the World Health Organization recommends looking for alternative effects. Gotu kola leaf extract contains metabolic substances such as steroids,saponins, flavonoids, phenolics that can be used as larvicides. This study aimed to determine the effectiveness of the larvicide extract of pegagan (Centella asiatica L. Urban) on the mortality of Culex quinquefasciatus larvae. This study used an experimental research design with a posttest only control group design using 4 concentration groups and 2 control groups, consisting of 4 repetitions in each, namely concentrations of 125 ppm, 250 ppm, 500 ppm, 1000 ppm, abate positive control and aquadest negative control. with the mean larval mortality was 31%, 65%, 81%, 98% which was observed for 48 hours. The number of larval deaths was analyzed using the Kruskall-Wallis test and logit analysis. The results of the analysis showed that pegagan leaf extract had an effect on the mortality of Culex quinquefasciatus larvae with a significant value (p < 0.05), then the results of logit regression analysis showed the LC50 value of 206.71 ppm. The conclusion of this study was that the leaf extract of pegagan (Centella asiatica L. Urban) was effective against the mortality of Culex quinquefasciatus larvae.

Larvicidal Efficacy of a Tropical Seaweed (Dictyota ciliolata) Extracts on Vectorial Mosquito Species and Non-Target Effect on Guppy Fish (Poecilia reticulata)

Extracts of seaweeds are promising candidates for eco-friendly, safe, and biodegradable larvicides and as alternatives to chemical larvicides used in mosquito control strategies. This study evaluated the larvicidal effects of Dictyota ciliolata on the mosquito larvae of Aedes aegypti, Anopheles gambiae, and Culex quinquefasciatus. The seaweed was extracted using ethanol and methanol. The larvicidal assays were conducted per WHO standards by exposing twenty 4th instar larvae to 100, 200, 300, 400, 500, and 600 mg/L of the derived extracts. The LC50 and LC95 values were obtained by calculating the probit values of the observed mortalities. LC50 of the ethanolic and methanolic extracts of Dictyota ciliolata against Anopheles gambiae larvae were 238.45 mg/L and 497.28 mg/L respectively; 179.02 mg/L and 224.96 mg/L respectively against Aedes aegypti, and 167.49 mg/L and 226.69 mg/L respectively for Culex quinquefasciatus. The results established that ethanolic and methanolic seaweed extracts were most influential on Culex quinquefasciatus followed by Aedes aegypti and Anopheles gambiae. Although mortalities were recorded for Poecilia reticulata, such may not be enough to de-emphasize the observed larvicidal potentials of Dictyota ciliolata as some other factors could have been responsible for the said mortalities in the non-target species.

Pengaruh ekstrak daun pepaya (Carica papaya linn) terhadap larvasida Aedes aegypti

Background: Transmission of Dengue Hemorrhagic Fever (DHF) is strongly influenced by the presence of Aedes aegypti mosquito larvae. The most effective method for tackling DHF is by killing the presence of Aedes aegypti larvae. Reducing the negative impact of using chemical larvicides can be done through a safer alternative model, namely natural larvicides from plants. The plant studied with a characteristic ability to kill Aedes aegypti larvae is papaya leaves. Papaya leaf extract contains compounds of alkaloids, flavonoids, papain, saponins, tannins, and papain, which can kill Aedes aegypti larvae.Objective: This study aims to determine the effectiveness of papaya leaf extract (Carica papaya Linn) and the effect of concentration as Aedes aegypti larvicide.Method: The design used in this study was experimental, using 240 Aedes aegypti larvae, three treatments, and three repetitions. The research was carried out at the Laboratory of the Environmental Health Department of Aceh Health Polytechnic, Ministry of Health in 2021. The data was collected through observations every 1 hour for the first 3 hours. The analysis used was the One Way Anova statistical test and continued with the Least Significance Different (LSD) test at 95% CI.Results: The results showed that the average mortality of Aedes aegypti larvae was at a concentration of 10% (10), a concentration of 20% (13), and a concentration of 30% (16). The results of the Anova test showed that giving papaya leaf extract affected the mortality of Aedes aegypti larvae (p = 0.000). The most effective concentrations in killing Aedes aegypti larvae were 20% and 30%.Conclusion: Papaya leaf extract was very effective as a larvacide of Aedes aegypti, and it was found that concentrations of 20% and 30% were the best formulas for larvicides.

Preparation of a Nanoemulsion of Essential Oil of Acroptilon repens Plant and Evaluation of Its Larvicidal Activity agianst Malaria Vector, Anopheles stephensi.

Extensive use of chemical larvicides to control larvae, has led to resistance in vectors. More efforts have been conducted the use of natural products such as plant essential oils and their new formulations against disease vectors. Nanoformulation techniques are expected to reduce volatility and increase larvicidal efficacy of essential oils. In this study for the first time, a larvicide nanoemulsion from the essential oil of Acroptilon repens was developed and evaluated against Anopheles stephensi larvae under laboratory conditions. Fresh samples of A. repens plant were collected from Urmia, West Azarbaijan Province, Iran. A clevenger type apparatus was used for extracting oil. Components of A. repens essential oil (AEO) were identified by gas chromatography-mass spectrometry (GC-MS). All larvicidal bioassay tests were performed according to the method recommended by the World Health Organization under laboratory condition. Particle size and the morphologies of all prepared nanoformulations determined by DLS and TEM analysis. A total of 111 compounds were identified in plant. The LC50 and LC90 values of AEO calculated as 7 ppm and 35 ppm respectively. AEO was able to kill 100% of the larvae in 4 days. The nanoemulsion of AEO showed a weak effect on the larvar mortality. It may therefore be suggested that this kind of nanoemulsion is not appropriate for the formulation as a larvicide. It is important to screen native plant natural products, search for new materials and prepare new formulations to develop alternative interventions with a long-lasting impact.

Chemical composition and larvicidal activity of the essential oil of Pimenta dioica leaves

In this study, we investigated the main constituent, the predominant class and biological activity of the essential oil extracted from the leaves of Pimenta dioica and the pattern of the major constituent against larvae in the third stage of Aedes aegypti. For this reason, we extracted the oil by hydrodistillation, identified its components by gas chromatography coupled with mass spectrometry (GC/MS) and calculated the lethal concentration (LC50) of the larvicidal activity using the Reed-Muench method. The results show that the oil consists mainly of eugenol, in which the phenylpropanoid class predominated and the lethal concentration, LC50, was 38.86 μg mL-1at a confidence level of 2.25 μg mL-1, while the eugenol standard presented LC5079.75 μg mL-1at a confidence level of 2.10 μg mL-1. Given the facts, we conclude that the oil is more active than the standard and that it has the potential to replace chemical larvicides.

New Bioinsecticides From Combination Extract of Leaf and Flower of Breadfruit (Artocarpus Altilis) On Mortality of Aedes Aegypti Larvae

The main vector for the spread of dengue fever is the female mosquito Aedes aegypti. In Indonesia, chemical larvicides are commonly used to control Aedes aegypti larvae. Bioinsecticides made from plants are one option for environmentally friendly larvae control. Leaves and flower of breadfruit Artocarpus altilis contains toxic compound that can function as larvicides. This experimental study used combination of leaf and flower of breadfruit expect that the combination of the two extracs was synergistic and it was more effective in killing Aedes aegypti larvae. The third instar Aedes aegypti larvae was used and divided into control group and test group with concentrations 1000, 2750, 4500, and 6250 ppm and replicated in 3 times with observations every 6, 9, and 24 hours. To identify the significant difference, the mortality data was analyzed using ANOVA and Duncan's test. In probit analysis, LC50 value of breadfruit leaf extract was 1871 ppm with LT50 was 4.2 hours. LC50 value of breadfruit flower extract was 2531 ppm with LT50 was 10.8 hours. LC50 value of the combination of breadfruit leaf and flower extract was 903 ppm with LT50 was 3.7 hours. Based on these studies, it may be indicated that breadfruit leaves and flowers was more effective in killing Aedes aegypti larvae than single extracts

Larvicidal Activity of Leaf Extract From Mauritiella armata (Aceraceae) on Aedes aegypti and Culex quinquefasciatus (Culicidae)

The mosquitoes Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae) are important vectors of several arboviruses, and are relevant public health problems. Conventional control, using chemical larvicides have selected resistant Culicidae populations and caused negative effects on the environment and human health. However, the use of plant extracts has represented a sustainable alternative for insect control. Popularly known as Xiriri, Mauritiella armata (Mart.) Burret (Aceraceae) is an abundant palm tree in Vereda ecosystems and has economic and social importance. In this study, the aim was to evaluate the larvicidal activity of the aqueous extract (AE) leaves of this plant on Ae. aegypti and Cx. quinquefasciatus larvae. The mortalities of larvae were analyzed after treatment with four concentrations of the extract, comparing with a negative control using mineral water. The AE promoted 100% efficacy against Ae. aegypti larvae at 7.9 mg/mL. The lethal concentration to promote 90% mortality of Cx. quinquefasciatus larvae was estimated at 30.57 mg/mL. After chromatographic analyses, flavonoids, catechin and carbohydrates were detected. AE from M. armata leaves presented high larvicidal activity against Ae. aegypti and Cx. quinquefasciatus, and represents a promising alternative to be used in vector control.

Larvicidal potency of Spatholobus parviflorus (DC.) Kuntze against Aedes albopictus (Diptera: Culicidae).

Aedes albopictus (Diptera: Culicidae) is one well-established vector of a series of mosquito-borne diseases. The larval stage of their life cycle is best suited to control a large population of mosquitoes easily. Controlling the larval stage of such vectors can also control the spread of the pandemic disease through the vector. Larvicides, which are synthetic, is a promising solution now. This kind of synthetic larvicides affects humans and animals equally and damages the environment through unscientific and widespread use. Beyond that, their continued use could create selection pressure and, thus, a resistant population. Plant-based larvicide is a way to overcome the shortcomings of synthetic larvicides. This study infers the larvicidal potency of Spatholobus parviflorus (DC.) Kuntze solvent extracts (SPSE) and crude water extracts (SPWE) against Aedes albopictus, using the dose-response larvicidal assay. The assay conducted using different concentrations of extract (0.1, 0.2, 0.3, 0.4, and 0.5%) and standard (bleaching powder), with the concentrations 0.01, 0.02, 0.03, 0.04 and 0.05%. The nourishment of the larvae is maintained by supplementing each of the Petri plates with 10 mg of larval food. The mortality of the nascent is recorded in a successive time interval of 12 h, up to 72 h. A significant (P<0.05) mortality was observed in SPWE of the leaf. The observed data analyses using Log probit analysis, and the highest LC50 (lethal concentration to kill 50% of the population), 0.57 mg/ml, is observed at the 24th h of the larvicidal assay. The lowest LC50, 0.35 mg/ml is observed at the 60th h of the larvicidal assay. In conclusion, the results show that S. parviflorus leaf water extract (SLWE) has significant larvicidal activity against A. albopictus, and this is the first account for the larvicidal potency of S. parviflorus. The study concludes that S. parviflorus is an excellent candidate plant for the development of a plant-based larvicide. This possibly influences a reduction in the use of typical household bleach and conventional chemical larvicides.

Z. mauritiana Leaves as Larvasidal Alternatives

The development of resistance to chemical insecticides among mosquitos has been considered as a setback in vector control. However, the use of chemical insecticides is often toxic to both human and non-target animals, thus it needs the development of natural insecticides. This study aims to analyze the larvicidal effect of Z. mauritiana leaves as a natural larvicidal that is friendly to the environment. This research will outline the larvicidal effect of Z. mauritiana leaves and discuss the significance of addressing this natural larvicide against Aedes aegypti larvae. Methods and Material in this study, we developed a mosquito larvacide by extracting Z. mauritiana leaves with the maceration method. We extracted Z. mauritiana leaves into 5 different concentrations (1%, 3%, 5%, 7%, 9%) and its effect compared to the current chemical larvicide (1% of temephos). Data analysis was performed by using the computer and statistical of variance test One Way Anova. This experiment was successfully 100% killed Aedes aegypti in 24 hours of the intervention of 9% extract of Z. mauritiana leaves which was a powerful effect compare to recent studies. The intervention of concentration variations was significantly associated with larvae mortality (p ≤ 0,001).

Chemical composition and larvicidal activity of essential oil of the bark of Citrus sinensis (L.) Osbeck

Aim: We determined the chemical composition and larvicidal activity of the essential oil distilled from the Citrus sinensis (L.) Osbeck husks and the pattern of the major constituent. Materials and methods: For this, we distill the oil by hydrodistillation, identify the components by gas chromatography coupled with mass spectrometry (GC-MS), test the larvicidal activity against Aedes aegypti and calculate the lethal concentration at 50% (LC50) by the Reed-Muench method and the confidence interval by the Pizzi method for both oil and standard. Results: it showed that the oil consists mostly of limonene and showed larvicidal activity (LC50 of 199.01(± 2.10) μg·mL-1) greater than the lemonade standard (126.03 (± 2.09) μg·mL-1). Conclusion: Therefore, we conclude that distilled oil has the potential to replace chemical larvicides.