Insect Repellent Research Articles

Formulation of Herbal Mosquito Repellent From Essential Oil Extracted Form Citrus Sinensis (Orange)

One of the infectious diseases that still poses a health risk to the society is malaria. Malaria is spread by insects called Anopheles sp. brought on by parasitic plasmodium sp. Owing to their high citric acid concentration, oranges have a sour flavor and a crisp scent. Orange peel essential oils are generally suitable for use as deodorizers with anti-mosquito spray. Due to their dislike of perfumes, mosquitoes can be sent away by orange peels. Oil-soluble (lipophilic) gologan organic molecules called terpenes and terpenoids are found in essential oils. With changes in active components infusion of orange peel F1 (20%), F2 (40%), this study intends to determine the usage of citrus peel waste into mosquito repellent spray compositions as an alternative to malaria prophylaxis

Thermodynamic and kinetic models for the photolytic and hydrolytic degradation of picaridin: A computational and theoretical study

The popularity of insect repellents presents the opportunity for continuous human and environmental exposure to such chemical mixtures. Consequently, the effects of their chemical components on human health and environmental safety is significantly reliant on their stability and hence, residence times under typical environmental conditions. Hence, for the first time, a thorough density functional theoretical (DFT) study on some possible hydrolytic and photolytic degradation pathways is presented and applied in the derivation of a comprehensive kinetic model, allowing evaluation of the residence time of picaridin; a very popular insect repellent. These results show that picaridin undergoes very slow hydrolysis via two pathways which present activation free energy barriers (ΔG‡) of ca. 225 and ca. 247 kJ mol−1 due to the asynchronous formation of four-membered cyclic activated complexes in both cases. Similarly, their photolytic transformations occur via two pathways, both of which are limited by the formation of the initial radical cation.

Drivers of autochthonous malaria cases over time: could the Central European present the African future?

BackgroundResults of spatial and temporal comparison of malaria hotspots and coldspots could improve the health measures of malaria control and eradication strategies. The study aimed to reveal the spatially and temporally independent correlations between the potentially most effective background variables and the number of autochthonous malaria cases.MethodsRelationships between malaria cases and background variables were studied in 2 km × 2 km sized quadrates (10 Central European and 10 African). In addition to the current habitat structure of the African sites, annual precipitation, and annual mean temperature, data of the above parameters detected in the nineteenth and twentieth centuries and currently in the Central European sites were included in the analyses (n = 40). Mann–Whitney tests, Principal Component Analysis, and Generalized Linear Models were used for the examinations.ResultsIn addition to the apparent significant positive correlation of malaria cases with annual rainfall and mean temperature, several correlations were found for habitat parameters. The cover of marshlands in the 19th-century habitat structure of Central European quadrates was considerably the same as in the recent African ones. The extent of rural residential areas was significantly smaller in the 19th-century habitat structure of Central European quadrats than in present-day African ones. According to the revealed correlations, the surface cover of rural residential areas is the main driver of the number of autochthonous malaria cases that we can directly impact.ConclusionsThe study confirmed with historical comparison that not only the annual rainfall and mean temperature, the cover of marshlands and other habitats with breeding sites, but also the elements of the rural human environment play a significant role in the high number of autochthonous malaria cases, probably through the concentration and enhancing sites for vector mosquitoes. The latter confirms that a rapid urbanization process could reduce malaria cases in the most infected areas of Africa. Until the latter happens, extensive biological control of Anopheles larvae and chemical control (both outdoor and indoor) of their imagoes, further mosquito nets, repellents, and carbon dioxide traps will need to be applied more widely in the most heavily infested areas.

Association between early-life mosquito repellents exposure and ADHD-like behaviours.

Limited research has explored the impact of mosquito repellents exposure during early life on ADHD symptoms. This study aimed to explore the associations of exposure to mosquito repellents from pregnancy to 3years old and the prevalence of ADHD-like behaviours among children aged 3-9years, and further identify the sensitive exposure period. A cross-sectional study was conducted, including 12275 children in Hefei City, China. Exposure was self-reported via primary caregivers. ADHD-like behaviours were measured by the Swanson, Nolan and Pelham, version IV scale (SNAP-IV), and Conners' Parent Rating Scale (CPRS). Cross-over analysis, binary logistic regression and linear regression were employed. After adjusting for confounding variables, early-life exposure to mosquito repellents was associated with a higher risk of ADHD-like behaviours (OR=1.81, 95% CI=1.49-2.19). By comparing the strength of the association for each subgroup, we found exposure during 1-3years old was a sensitive period (OR=1.89, 95% CI=1.25-2.87) by the cross-over analysis. Furthermore, we found a dose-response relationship in which the likelihood of ADHD-like behaviours increased with children's early-life mosquito repellents exposure dose. Early-life exposure to mosquito repellents is linked with an elevated risk of ADHD-like behaviours in children, with a sensitive period identified during 1-3years old.

Chemical Composition, Repellent, and Oviposition Deterrent Potential of Wild Plant Essential Oils against Three Mosquito Species.

In this study, the chemical composition, repellent, and oviposition deterrent effects of five plant essential oils (EOs) extracted from Lantana camara (Verbenaceae), Schinus terebinthifolia (Anacardiaceae), Callistemon viminalis (Myrtaceae), Helichrysum odoratissimum (Asteraceae), and Hyptis suaveolens (Lamiaceae) were evaluated against Aedes aegypti, Anopheles gambiae, and Culex quinquefasciatus. When tested at 33.3 µg/cm2, L. camara, S. terebinthifolia, C. viminalis, and H. odoratissimum were effective repellents against Ae. aegypti (89%, 91%, 90%, and 51% repellency, respectively), but they were less repellent against An. gambiae (66%, 86%, 59%, and 49% repellency, respectively). Interestingly, L. camara, S. terebinthifolia, C. viminalis, and H. odoratissimum exhibited 100% repellency against Cx. quinquefasciatus at 33.3 μg/cm2. In time-span bioassays performed at 333 μg/cm2, the EO of L. camara exhibited 100% repellence against Ae. aegypti and An. gambiae for up to 15 min and against Cx. quinquefasciatus for 75 min. The oviposition bioassays revealed that L. camara exhibited the highest activity, showing 85%, 59%, and 89% oviposition deterrence against Ae. aegypti, An. gambiae, and Cx. quinquefasciatus, respectively. The major compounds of L. camara, S. terebinthifolia, and C. viminalis were trans-β-caryophyllene (16.7%), α-pinene (15.5%), and 1,8-cineole (38.1%), respectively. In conclusion, the L. camara and S. terebinthifolia EOs have the potential to be natural mosquito repellents.

Flower Power: An Overview on Chemistry and Biological Impact of Selected Essential Oils from Blossoms

AbstractNatural raw materials such as essential oils have received more and more attention in recent decades, whether in the food industry, as flavorings and preservatives, or as insecticides and insect repellents. They are, furthermore, very popular as fragrances in perfumes, cosmetics, and household products. In addition, aromatherapy is widely used to complement conventional medicine. This review summarizes investigations on the chemical composition and the most important biological impacts of essential oils and volatile compounds extracted from selected aromatic blossoms, including Lavandula angustifolia, Matricaria recutita, Rosa x damascena, Jasminum grandiflorum, Citrus x aurantium, Cananga odorata, and Michelia alba. The literature was collected from PubMed, Google Scholar, and Science Direct. Blossom essential oils discussed in this work are used in a wide variety of clinical issues. The application is consistently described as safe in studies and meta-analyses, although there are notes that using essential oils can also have side effects, especially dermatologically. However, it can be considered as confirmed that essential oils have positive influences on humans and can improve quality of life in patients with psychiatric disorders, critically ill patients, and patients in other exceptional situations. Although the positive effect of essential oils from blossoms has repeatedly been reported, evidence-based clinical investigations are still underrepresented, and the need for research is demanded.

Re-emergence and influencing factors of mountain-type zoonotic visceral leishmaniasis in the extension region of Loess Plateau, China.

To understand the epidemiological distribution characteristics of mountain-type zoonotic visceral leishmaniasis (MT-ZVL) in Yangquan City, Shanxi Province, China, from 2006 to 2021, to explore the influencing factors leading to the re-emergence of the epidemic, and to provide a basis for the formulation of targeted control strategies. Case information spanning from 2006 to 2021 in Yangquan City was collected for a retrospective case-control study conducted from June to September 2022. A 1:3 matched ratio was employed. A questionnaire was utilized to gather data on basic information, demographic characteristics, awareness of MT-ZVL knowledge, residence, and dog breeding and living habits. The study employed a multifactorial conditional stepwise logistic regression model to analyze the influencing factors. A total of 508 subjects was analyzed. Risk factors for MT-ZVL included the use of soil/stone/concrete as building materials (OR = 3.932), presence of nearby empty/stone stack houses (OR = 2.515), dog breeding (OR = 4.215), presence of stray dogs (OR = 2.767), and neighbor's dog breeding (OR = 1.953). Protective factors comprised knowledge of MT-ZVL (OR = 0.113) and using mosquito repellents (OR = 0.388). The findings indicate significant associations between environmental and behavioral factors and MT-ZVL incidence in Yangquan City, Shanxi Province, China, from 2006 to 2021. These results underscore the importance of public awareness campaigns and targeted interventions aimed at reducing exposure to risk factors and promoting protective measures to mitigate the re-emergence of MT-ZVL outbreaks. House building materials, presence of neighboring empty houses, breeding domestic dogs and distribution of stray dogs surrounding the home are risk factors for MT-ZVL. Awareness of MT-ZVL and implementation of preventive measures during outdoor activities in summer and autumn are protective and may reduce the risk of MT-ZVL.

REVIEW OF COMPREHENSIVE STUDY ON DIFFERENT ACTIVITIES OF PRIYANGU

The chemical components found in plants make them a vital and fundamental component of complementary and alternative medicine. Traditional medicine has made use of plants of the Aglaia genus, the species in the Meliaceae family. the genus Aglaia has more than one hundred. Juss. Aglaia elaeagnoidea In the Western Ghats and other dry regions of India, Benth trees grow in dense, damp woods. Priyangu and chokkala are two of the common names. Rural people use the bark and leaves of this tree, much like they do with other Aglaia species. The Aglaia elaeagnoidea plant's leaves and stem bark are used in Indian medicine, specifically Ayurvedic medicine, to treat a variety of conditions, including skin diseases, tumors, insect repellent, antibacterial, anti-inflammatory, wound-healing, and anti-cancer. Numerous studies have documented the existence of phytoconstituents in plant extracts, providing empirical evidence for the anti-inflammatory, analgesic, anti-tumor, and anti-hypertensive effects of plants. This review includes information on Aglaia elaeagnoidea phytochemistry and pharmacological properties.

The Utilization of Citronella (Cymbopogon nardus) Oil and Butterfly Pea Flower Extract in The Production of Mosquito Repellent Lotion

The Utilization of Citronella (Cymbopogon nardus) Oil and Butterfly Pea Flower Extract in The Production of Mosquito Repellent Lotion

Moringa Leaf Powder as Environmentally Friendly Repellent Agent for Controlling the Warehouse Insect Pest for Black Soybean Grain

Black soybean grain (Glycine max L. Merril.) storage is susceptible to insect pests such as Callosobruchus analis (F.), which feeds on soybeans. Steroids/triterpenoids, phenolics, alkaloids, tannins, and terpenoids found in moringa leaf powder can be employed as insect repellents in black soybean grain warehouses. The purpose of this study was to ascertain how applying plant-based insecticides made from powdered moringa leaf will affect the amount of C. analis (F.) that died, the severity of the damage, and the weight loss of black soybean seeds of the Detam 4 Prida varieties. The study took place from August to October 2019 at an elevation of 878 meters above sea level in the Biology Laboratorium of the Agriculture Faculty, University of Winaya Mukti. An experimental design including five treatments and five replications was employed as the research methodology. A was not given any moringa leaf powder; B, C, D, and E each received 0.25, 0.75, and 1 grams of moringa leaf powder, fine powder, and so on. 10 pairs of C. analis (F) per jar were used in each treatment, which involved 100 g of black soybean grain. In the storage of black soybean grain, the percentage of seed damage, weight loss, the number of eggs, larvae, pupae, and images, and mortality of C. analis (F) were all impacted by 0.75 g of moringa leaf powder, according to the findings. According to this research, C. analysis, a warehouse insect pest, is effectively repelled by powdered moringa leaf (F.).

Efektivitas Biolarvasida Kombinasi Ekstrak Daun Sirsak (Annona muricata) dan Bunga Marigold (Tagetes erecta L.) sebagai Pembasmi Jentik Nyamuk

This research aims to determine the effectiveness of using a biolarvicide combination of soursop leaf extract and marigold flowers as an exterminator for mosquito larvae. This research included a laboratory experiment using a completely randomized 2 factorial design. The first factor is a combination of soursop leaf extract and marigold flowers, namely, a) 75%:25% (F1); b) 50%:50% (F2); c) 25%:75% (F3). The second factor is the treatment dose, namely, a) 1% (D1); b) 2% (D2); c) 2.5% (D3). Each factor was repeated 3 times. Data analysis uses a non-parametric test, namely Kruskal-Wallist. The results of the study showed that the soursop leaf and marigold flower extract formula 75%:25% was most effective against mosquito larvae mortality at a dose of 2.5% within an observation period of 6 hours. In conclusion, soursop leaf and marigold flower extracts are effective mosquito larva repellents. Keywords: Biolarvicide, Marigold Flowers, Soursop Leaves, Effectiveness, Mosquito Larvae

Green modifications for rendering cotton fabric with antibacterial, anti-mite, and mosquito-repellent functions using single natural eugenol

Cotton fabrics are widely used in everyday life; however, increasing their versatility through green modifications remains a challenge. The current mainstream approach merely physically attaches the additives onto the fibers, resulting in low binding affinity. In this study, novel cotton fabrics (Cotton-Si-EU) with long-lasting antibacterial, anti-mite, and mosquito-repellent properties were facilely fabricated in a green procedure. In contrast to conventional coating and physical addition methods, the eugenol graft modification ensured the safety, environmental friendliness and long-lasting functionality of the Cotton-Si-EU. In addition, Cotton-Si-EU fabrics retained the softness, comfort, breathability, and moisture absorption originating from the cotton fabric. Cotton-Si-EU also showed over 99.99% antibacterial, 73% anti-mite, and 75% mosquito repellent rates, simultaneously destroying microorganisms and insects through oxidative stress, inhibiting enzyme activity, affecting cell structure, and other mechanisms. More importantly, after 50 washing cycles, the fabrics still exhibited durable antibacterial properties higher than the AAA requirements, indicating high functional longevity. In addition, good cytocompatibility, hemocompatibility, and negligible skin irritation demonstrated excellent biological safety. Therefore, this study is of great significance in providing a reference for modifying cotton fabrics using an infinite number of natural products after screening, which will broaden the application scope and improve the safety level of functional cotton fabrics.

Epidemiology of cutaneous leishmaniasis in children of Khyber Pakhtunkhwa, Pakistan.

In Pakistan, cutaneous leishmaniasis is an emerging tropical disease and a very high number (>70%) of children are afflicted by this marring infection. This study aimed to scrutinise the prevalence, spatial distribution and socio-demographic and behavioural risk factors associated with cutaneous leishmaniasis in children aged <5-15 years in Khyber Pakhtunkhwa. A total of 1, 559 clinically confirmed records of children diagnosed with cutaneous leishmaniasis (January-December) from 2020 and 2022 were obtained from selected district hospitals. In addition, a risk factors-related questionnaire was administered to 1, 011 households (400 in 2020 and 611 in 2022) in nine districts during a household survey. The maximum number of cutaneous leishmaniasis cases was recorded in 2022 (n = 877, 56.25%) as compared to 2020 (n = 682, 43.75%). The hospital records showed a greater number of male patients in the 2022 cohort (n = 603, 68.76%). The highest number of cases were observed in children aged 5-9 years in 2022 (n = 282, 32.16%) and 2020 (n = 255, 37.39%). In 2020 and 2022, cutaneous leishmaniasis cases showed peak aggregation in March (n = 118, 17.3%) and January (n = 322, 36.72%). From a spatial analysis, the maximum number of cutaneous leishmaniasis cases was recorded at 59-1700 m elevation in various land-use/land-cover and climatic regions with quaternary alluvium rock formations. A multivariate logistic regression model analysis of risk factors from the households survey suggested that age group, socio-economic status, construction materials of the house, use of insect repellents, Afghan refugee camps in the village/district, knowledge and biting times of sand flies, frequent use of mosquito bed nets, presence of domestic animals in the house, knowledge of the transmission period and peak month of leishmaniasis infection increased the risk of acquiring cutaneous leishmaniasis (p value < 0.05). Our analysis demonstrated that cutaneous leishmaniasis in children is influenced by a variety of environmental, socio-demographic and behavioural risk factors in Khyber Pakhtunkhwa. The increase in recorded cases of cutaneous leishmaniasis in children in 2022 compared to 2020 suggests that the infection likely extended to new foci in the province.

Comparison of the cytotoxicity and zebrafish embryo toxicity of insect repellent ingredients: p-Menthane-3,8-diol synthesized by green chemistry from Eucalyptus citriodora and N,N-diethyl-meta-toluamide

Bio-sourced insect repellents are becoming more popular due to their safer applications. Known for its strong fly-repellent property, Cis, trans-para-menthane-3,8-diol (PMD) is the main component of the lemon eucalyptus essential oil and is synthesized from citronellal. In April 2005, US Centers for Disease Control approved two fly repellents that do not contain N,N-diethyl-meta-toluamide (DEET), including PMD. Due to the intentional and pervasive human exposure caused by DEET as insect repellent, concerns have been raised about its toxicological profile and potential harm to people. We hypothesized PMD would have a different toxicological profile than DEET. We synthesized PMD from Eucalyptus citriodora using green chemistry methods and analyzed its structures by 1H-NMR,13C-NMR, and GC/MS spectral methods. We used MTS assay to determine the percentage inhibition of PMD and DEET on keratinocyte (human epidermal keratinocyte [HaCaT]) cells. The xCelligence system was used and followed at real time. Effects of PMD and DEET on zebrafish embryo development were monitored and levels of lipid peroxidation, glutathione-S-transferase (GST), superoxide dismutase (SOD), and acetylcholinesterase (AchE) were evaluated at 72 h post-fertilization using spectrophotometric methods. Our results showed that while DEET inhibited human keratinocyte cell growth, while imporved cell viability and proliferation was exposed in PMD exposed group. In zebrafish embryos, PMD was less toxic in terms of development, oxidant-antioxidant status, and AChE activities than DEET. Based on these results we suggest an efficient method using green chemistry for the synthesis of PMD, which is found to be less toxic in zebrafish embryos and human keratinocyte cells.

Mosquitoes do not influence Cotton Mouse (Peromyscus gossypinus) giving-up densities

Abstract It is commonly recognized that predation and the risk of predation can have profound effects on behaviors and population ecology of prey. Comparatively, little attention has been paid to the trade-offs hosts make to manage the risk of parasitism, but there is evidence that hosts make behavioral trade-offs to avoid parasitism in ways that resemble those made by prey animals under the risk of predation. Mosquitoes are common hematophagous ectoparasites which parasitize a wide range of vertebrates, resulting in blood loss, distraction, and disease transmission. Many hosts engage in defensive behaviors to repel or kill mosquitoes and these behaviors likely come at the expense of activities such as foraging and vigilance for predators. We placed a mosquito attractant (BG-Sweetscent) and repellant (allethrin) near artificial foraging patches in areas where mosquitoes were common and measured the amount of grain left after a night of foraging (giving-up density) to investigate whether mosquitoes influenced Cotton Mouse (Peromyscus gossypinus) foraging. We predicted that in patches with mosquito attractants, mosquito harassment would cause mice to engage in defensive behaviors which would distract or deter them from foraging, resulting in less grain consumption relative to control patches. Conversely, we predicted that in mosquito-repellent patches, mice would experience less harassment, resulting in more grain consumption. Indoor arena trials found no evidence that the mosquito treatments influenced cotton mouse behavior in the absence of mosquitoes. However, we found no evidence that mosquito treatments affected giving-up densities.

Augmenting large language models with chemistry tools

AbstractLarge language models (LLMs) have shown strong performance in tasks across domains but struggle with chemistry-related problems. These models also lack access to external knowledge sources, limiting their usefulness in scientific applications. We introduce ChemCrow, an LLM chemistry agent designed to accomplish tasks across organic synthesis, drug discovery and materials design. By integrating 18 expert-designed tools and using GPT-4 as the LLM, ChemCrow augments the LLM performance in chemistry, and new capabilities emerge. Our agent autonomously planned and executed the syntheses of an insect repellent and three organocatalysts and guided the discovery of a novel chromophore. Our evaluation, including both LLM and expert assessments, demonstrates ChemCrow’s effectiveness in automating a diverse set of chemical tasks. Our work not only aids expert chemists and lowers barriers for non-experts but also fosters scientific advancement by bridging the gap between experimental and computational chemistry.

Formulation and Evaluation of Mosquito Repellent Candles using Dried Catnip Leaves

A mosquito is a little fly that is a member of Culicidae family. They are said to be among the deadliest insects on the planet, spreading illness and taking millions of lives in the process. For many years, diseases spread by mosquitoes have been the primary cause of illness and mortality in humans. Types of Mosquito Repellents: 1) Physical methods of Mosquito Repellent 2)Mechanical method of mosquito repellent 3) Chemical method of mosquito repellent. In this research focuses on natural method of mosquito repellenant property. The Active constituent used is dried leaves of catnip. Various other ingredients like sawdust, camphor, eucalyptus oil was used. It's burning time, smoke visibility was seen.The main purpose of this formulation is to make a mosquito repellent which is free from side effects and does not cause any irritation and harm to the Humanlives

Janus outdoor protective clothing with unidirectional moisture transfer, antibacterial, and mosquito repellent properties

Personal protective clothing with versatile and durable features is highly desirable for daily and specific environmental scenarios. Especially for outdoor workers or sports enthusiasts, prolonged outdoor exposure requires their clothing to be more functional to cope with a wide range of situations, such as heat stress in summer, odor generation after sweating, and mosquito bites. These not only reduce the wearing comfort of clothing, but also bring potential heat stroke, skin infections and diseases brought by mosquitoes. Currently, most outdoor protective clothes focus on a single function, such as waterproofing and UV protection and are not able to cope with the demand of multiple protections. In this paper, we developed permethrin-containing triblock cationic polymers (PTCPs) that can multi-functionalize outdoor clothing. Benefiting from their high affinity to polyester fibers, PTCP modified polyester yarns were obtained by an aqueous based finishing process. After that, a scalable machine-knitting fabrication technique is employed to fabricate Janus outdoor protective clothes (Janus-OPC). The as-prepared Janus-OPC exhibited excellent one-way moisture transfer properties (forward cumulative one-way transfer index (OWTI) of 924.23%, and backward OWTI of −690.52%), antimicrobial properties (97.73% and 99.72% against E. coli and S. aureus, respectively), and mosquito repellent properties (repelling rate of 76.19%). Moreover, the protective performance of the Janus-OPC was maintained after 50 times of equivalent home laundering cycles. This multifunctional protective clothing opens up a new direction for the next-generation outdoor wear.

Genotoxic effects of the insect repellent n, n-diethyl-meta-toluamide (DEET) and detection of retinoblastoma gene expression in human lymphocytes: A pilot study

Genotoxic effects of the insect repellent n, n-diethyl-meta-toluamide (DEET) and detection of retinoblastoma gene expression in human lymphocytes: A pilot study

Apparent anti‐parasite behaviour in the Norfolk Island green parrot Cyanoramphus cookii

AbstractBirds must cope with all manner of ectoparasites, from insects and mites to bacteria and fungi. During their grooming routine, several Norfolk Island green parrots Cyanoramphus cookii were observed and photographed, and a pair was videoed, biting off and chewing small pieces of lateral shoot and bark of pepper trees Piper excelsum and working the chewed material through their feathers. They also stripped the leaves and rubbed their beaks along the branches before extracting preen oil. Pepper trees are a well‐known source of piperine and other potent aromatic chemicals that are insect repellent and antimicrobial. This appears to be a rare example of a bird using plant material to anoint themselves, which we interpret as a way to repel blood‐sucking insects and ectoparasites and, possibly, void endoparasites, thereby improving fitness.