Mosquito Repellent Activity Research Articles

REVIEW: PLANTS WITH REPELLENT ACTIVITY

Mosquitoes are vectors of illnesses, such as encephalitis, dengue, filariasis, intestinal sickness, and encephalitis. These diseases have become epidemics in Indonesia and around the world. Natural repellents are alternatives for preventing mosquito-borne diseases that are safe, easily degradable, and eco-friendly. This review aimed to identify compounds in plants with mosquito repellent activity. Data were obtained from national and international journals using search platforms, including PubMed, Scholar, SciDirect, and Hindawi. This review focuses on plants with repellent activity, their resulting repellent activity, the content of bioactive compounds, and the mosquito species used. Many plants contain naturally occurring compounds that can repel mosquitoes. Following scientific research, 14 bioactive compounds have been shown to have repellent activity in plants. Keywords: repellent, volatile oil, mosquitos, bioactive compounds, narrative literature review

Phytochemical Analysis of Dried Hevea brasiliensis (Will. Ex Adr. De Juss.) Muell. et Arg Leaves Collected from the Ovitrap with Mosquito Larvae

In the modern culture the paddy fields are converted into rubber plantations and its plays a good breeding source for mosquitoes especially during rainy seasons. Our present investigation is to find out the phytochemical constituents present in Hevea brasiliensis dried leaves collected from the ovitrap as a preliminary study to find out the mosquito repellent activity. The obtained result suggests that the control showed the presence of terpenoid, phenol, alkaloid and tannin. Similarly methanol extract showed the presence of phenol, tannin and steroid; chloroform extract showed the presence of terpenoid, flavonoid, tannin and steroid; acetone extract showed the presence of alkaloid, tannin, steroid and aminoacid and aqueous extract showed the presence of steroid and aminoacid. Moreover, the results suggest that the dried leaf collected from the ovitrap contains various phytoconstituents which can be utilized for industrial use.

Essential oils extracted from Citrus macroptera and Homalomena aromatica (Spreng.) Schott. exhibit repellent activities against Aedes aegypti (Diptera: Culicidae).

Mosquitoes alone transmit diseases to around 700 million individuals annually, killing approximately 0.7 million people every year worldwide. Considering the potential health risks linked with synthetic repellents, it has become vital to identify eco-friendly, natural repellents for mosquito control as well as to understand the underlying mechanism for mosquito repellent activity. To address this, objectives were set to extract essential oils from Citrus macroptera peel and Homalomena aromatica (Spreng.) Schott. rhizomes, evaluate their mosquito repellent activity against Aedes aegypti, and further explore their mosquito odorant receptor inhibition potential. The oils were extracted using Clevenger's apparatus, and properties like specific gravity, refractive index, and boiling point were evaluated and characterised using Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectroscopy (GC-MS). Aedes aegypti mosquito eggs collected from the Indian Council of Medical Research (ICMR), Dibrugarh, were reared in the Department of Pharmaceutical Sciences, Research Laboratory, to obtain adult Aedes aegypti mosquitoes for the mosquito repellent activity evaluation of the essential oils using the Human Bait technique'. Molecular docking studies were performed for the oil components against mosquito odorant binding proteins. Further, toxicity studies of these two oils were evaluated against human dermal fibroblast adult (HDFa) cells. The results revealed the presence of limonene (86.76%) and linalool (52.35%), respectively, in Citrus macroptera and Homalomena aromatica oils. It was found that the combination of the oils in a ratio of 1:1 showed mosquito repellent activity for up to 6.33 ± 0.23 h. Molecular docking studies showed the presence of major oil components having mosquito odorant receptor blocking potential comparable to N, N-diethyl-meta-toluamide (DEET), indicating a rationale for extended mosquito repellent action. Further, both of these oils were found to be non-cytotoxic against HDFa cells after 24 h. The encouraging mosquito repellent activity of these two oils as compared to synthetic mosquito repellent DEET might pave the way for the development of novel herbal mosquito repellent formulations containing these essential oils.

Formulation and evaluation of nanoemulgel loaded with essential oils with mosquito repellent activities

The mosquito repellent potential of plant materials, including essential oils, has been exploited for centuries. However, due to the volatility of essential oils, the protection against mosquitoes is short-lived. This study aimed to formulate citronella oil (CO) (Cymbopogon nardus) and palmarosa oil (PO) (C. martini) in the form of nanoemulgel (NEG) to delay their volatility and prolong protection time against mosquitoes. Nanoemulsions (NE) of both essential oils were prepared using ultrasonication after suitable hydrophilic-lipophilic balance (HLB) selection and phase diagram development. NEGs were formulated by mixing NEs and Carbopol 934 gel. Physicochemical characterizations, including in vitro release and permeation studies were conducted. Tween 80, Transcutol P and distilled water with 40 % glycerol were selected as surfactant, co-surfactant and aqueous components of the NEs, respectively. HLB values of 11 and 12 were found to be appropriate for CO and PO NEs preparation, respectively. The NEGs were kinetically stable and the formulation components were chemically compatible with each other. The NEG formulations prolonged the release of both essential oils for 24 h and significantly reduced the percentage permeation via cellulose acetate membrane as compared to NEs. Consequently, NEG could be a potential formulation to prolong the mosquito repellent activity of essential oils.

Phytochemical and Mosquito Repellent activities of <i>Citrus sinensis, Citrus reticulate and Citrus limon</i> Leaves

Phytochemical and Mosquito Repellent activities of <i>Citrus sinensis, Citrus reticulate and Citrus limon</i> Leaves

Larvicidal, Insecticidal and Mosquito repellent activity of Scented Geranium (Pelargonium species) essential oil against Malarial Vector; Anopheles stephensi

Larvicidal, Insecticidal and Mosquito repellent activity of Scented Geranium (Pelargonium species) essential oil against Malarial Vector; Anopheles stephensi

Chimpanzees select comfortable nesting tree species

Every evening, chimpanzees build sleeping “nests” in trees. In some studied communities, individuals appear to be selective about the tree species used, which has led researchers to hypothesize whether chimpanzees prefer trees that repel troublesome insects or/and that provide comfortable and stable structures. We investigate these hypotheses, or a trade-off between both, though study of tree species preference based on their biomechanical and/or biochemical properties in the Sebitoli chimpanzee community in Kibale National Park, Uganda. The ten tree species most frequently used for nesting were compared with ten abundant in their environment but not preferred for nesting. For these 20 tree species, we determined their biomechanical and morphological characteristics such as foliar density, foliar units form (shape and size) and branch rigidity. Their spatial repellent activity, previously tested against Anopheles gambiae was incorporated into the analysis. Chimpanzees chose tree species with medium-sized and elongated foliar units, high foliar density and branch with stiffer wood. In addition, most tree species with such mechanical and morphological properties also have mosquito repellent activity. These tree properties may provide a comfortable sleeping environment enhancing sleep quality. Finally, a comparison across chimpanzee communities would be relevant to understand whether these choices are not only ecological but also cultural.

Synergistic Repellent and Irritant Effects of a Mixture of β-Caryophyllene Oxide and Vetiver Oil against Mosquito Vectors.

Repellents play a major role in reducing the risk of mosquito-borne diseases by preventing mosquito bites. The present study evaluated the mosquito-repellent activity of β-caryophyllene oxide 1% (BCO), vetiver oil 2.5% (VO), and their binary mixtures (BCO + VO (1:1), BCO + VO (2:1), BCO + VO (1:2)) against four laboratory-colonized mosquito species, Aedes aegypti (L.), Aedes albopictus (Skuse), Anopheles minimus Theobald, and Culex quinquefasciatus Say, using an excito-repellency assay system. In general, the compound mixtures produced a much stronger response in the mosquitoes than single compounds, regardless of the test conditions or species. The greatest synergetic effect was achieved with the combination of BCO + VO (1:2) in both contact and noncontact trials with An. minimus (74.07-78.18%) and Cx. quinquefasciatus (55.36-83.64%). Knockdown responses to the binary mixture of BCO + VO were observed for Ae. albopictus, An. minimus, and Cx. quinquefasciatus, in the range of 18.18-33.33%. The synergistic repellent activity of BCO and VO used in this study may support increased opportunities to develop safer alternatives to synthetic repellents for personal protection against mosquitoes.

Encapsulated lemon oil and metal nanoparticles in biopolymer for multifunctional finishing of cotton and wool fabrics

This study examined the utilization of different metal nanoparticles encapsulated in biopolymer material in the presence or absence of lemon oil to cellulosic and proteinic fabrics to obtain textile material with mosquito-repellent, fragrance, and antibacterial Properties. Encapsulation of lemon oil into the biopolymers was performed using the mechanical homogenizing mixing method. several treatments for textile materials using pad-dry-packing procedures were devolved in the presence or absence of metal nanoparticles. the natural polymers were used in various concentrations (3%, 5%, and 10%). For each polymer, varied concentrations with encapsulated oil were utilized. Different methods were used to investigate the finished textile materials in terms of their physical-mechanical characteristics. The treated fabrics with AgNPs (5%) encapsulated in gelatin biopolymer give higher antimicrobial activity; the treated fabrics with TiO2NPs (5%) encapsulated in pectin biopolymer give higher mosquito repellent activity; and the treated fabrics with ZnONPs (5%) encapsulated in gelatin biopolymer give higher UPF values. The physical and mechanical qualities of the treated textiles perform well when compared to untreated cloth.

Potential Applications of Microencapsulated Essential Oil Components in Mosquito Repellent Textile Finishes

This study aimed to develop a cost-effective and eco-friendly mosquito-repellent textile finish based on microcapsules incorporated with limonene, camphor, linalool, menthol, and 1-octanol individually. Essential oil-based microcapsules were prepared by the emulsion extrusion microencapsulation method. The concentration of active components was determined by the gas chromatography-mass spectrometry (GC-MS) technique at different time intervals. The prepared microcapsules were incorporated into the textile finish to prepare an insect-repellent finish and applied to polyester: cotton (40:60) fabric using a conventional pad-dry cure method. Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) analyses were performed to ensure the presence and stability of essential oil components on the fabric. FT-IR spectra showed that peaks observed in the range of (3400–3200 cm−1) and (1720–1600 cm−1) correspond to –OH stretching and bending vibrations in both untreated and microencapsulated essential oil-treated fabric. Mosquito-repellent activity was assessed by exposing treated and untreated fabric to mosquitoes. To study the long-lasting impact of microencapsulation of essential oil components on fabric, mosquito repellency was repeated every 10 to 50 days. Fabrics treated with microencapsulated essential oil components presented higher and longer-lasting protection from mosquitoes than untreated fabrics. Menthol (97%), linalool (93%), and limonene (93%) encapsulated finishes showed significantly higher repellency (>90%) as compared with octanol finishes. The studied mosquito repellent finishes could be ideal candidates for textile finishing industries.

DEVELOPMENT OF HERBAL MOSQUITO-REPELLENT FORMULATIONS AND THEIR COMPARATIVE EVALUATION

Objective: The present research work aimed to develop herbal mosquito repellents as gels, incense sticks, and liquids for plug-in devices and also to assess their performance characteristics. Methods: Herbal materials possessing mosquito-repellent activity were selected from the literature review based on percentage repellency and protection period. In this study, lavender, rosemary, lemongrass, and cedarwood oils were selected as actives. Span 20 and tween 80 were used to emulsify the volatile materials and then incorporated into Carbopol 934 base to form F1 and F2 gels which were evaluated for homogeneity, pH, spread ability, viscosity, and extrudability. Incense sticks were developed using charcoal and jigat as base materials. The prepared incense sticks F3 and F4 were evaluated for burning time, ash weight, and smoke. Solutions F5 and F6 were prepared using surfactants and cosolvents and were evaluated for phase separation. All formulations were screened for their mosquito repellency by screen cage method and their performance was compared to that of the marketed herbal repellents. Results: Reared mosquitoes were identified as Culex species by microscopical observations of the antenna and maxillary palps. Mosquito repellency in 4 h is 93%, 87%, 89%, 79%, 89%, and 85% for F1, F2, F3, F4, F5 and F6, respectively. Among all, gel formulation F1 expressed the highest mosquito-repellent activity with 93% and is a better candidate. Conclusions: Gel, incense sticks, and liquids prepared for use in plug-in devices exhibited reasonably good percentage repellency comparable to that of the standard. All the developed formulations are suitable for indoor protection from mosquito bites. However, safety, stability, and field studies need to be carried out to demonstrate suitability for regular use.

Chemical Composition of Goniothalamus andersonii Bark and its Mosquito Repellent Activity

This study sought to identify the chemical composition of smoke condensate of Goniothalamus andersonii (Annonaceae) and comparatively evaluate the effectiveness of smoke condensate. The chemical composition has been determined by GC-MS. Five main components were contained in aqueous fraction, namely eugenol (25.31%), (E)-cinnamaldehyde (21.13%), hexamethylene diacrylate (7.0%), caryophyllene (6.25%), and ethyl oleate (4.3%). While, three main components were detected in the n-hexane fractions, namely guaiol (8.98%), α-eudesmol (5.71%), and (-)-cyperene (3.06%). Laboratory research was conducted to determine the repellency of the smoke condensate of Aedes aegypti mosquitoes at two levels of concentration (5.0% and 10.0%). Tests were carried out to establish the percentage reduction of mosquito landing for each of the concentrations. The synthetic insect repellent, N, N-diethyl-m-toluamide (DEET), was used as a standard at a similar level of concentration. At 5.0% concentration, DEET provided a better percentage reduction with 70.5% for up to 4 hours, compared to smoke condensate (44.5%). At 10.0%, DEET provided an 80.9% reduction in mosquito landing, which was significantly better, as compared to smoke condensate (61.9%). However, data analysis through a t-test demonstrated a significant difference between smoke condensate and DEET efficacy in both concentrations, with regards to treated and untreated arms (P < 0.05).

Mosquito repellent activities of citrus fruit peels

Mosquito repellent activities of citrus fruit peels

Essential oils of four wild plants inhibit the blood seeking behaviour of female Aedes aegytpi

Aedes aegypti (Diptera: Culicidae) mosquito is an important vector of many disease-causing pathogens. An effective way to escape from these mosquito-borne diseases is to prevent mosquito bites. In the current study, essential oils of Lepidium pinnatifidum, Mentha longifolia, Origanum vulgare, and Agrimonia eupatoria were evaluated for their repellent potential against Ae. aegypti females. Essential oils were extracted using steam distillation from freshly collected aerial parts of the plants and tested against 4–5 day old females of Ae. aegypti through the human bait technique for repellency and repellent longevity assays. The chemical composition of extracted essential oils was explored by gas chromatography coupled with mass spectrometry (GC-MS). The essential oils of L. pinnatifidum, M. longifolia, O. vulgare, and A. eupatoria at a dose of 33 μg/cm2 showed 100%, 94%, 87%, and 83% mosquito repellent activity, respectively. Furthermore, M. longifolia and O. vulgare essential oils exhibited 100% repellency at a dose of 165 μg/cm2, whereas A. eupatoria essential oil showed 100% repellency only at 330 μg/cm2. In the time-span bioassay, M. longifolia and O. vulgare essential oils showed protection against Ae. aegypti bites for 90 and 75 min, respectively whereas both A. eupatoria and L. pinnatifidum were found active for 45 min. Phenylacetonitrile (94%), piperitone oxide (34%), carvacrol (20%) and α-pinene (62%) were the most abundant compounds in L. pinnatifidum, M. longifolia, O. vulgare and A. eupatoria essential oils, respectively. The current study demonstrates that M. longifolia and O. vulgare essential oils possess the potential to be used as an alternative to synthetic chemicals to protect humans from mosquito bites.

Amazon Rainforest: A Natural Source for New Therapeutic Alternatives against Neglected Tropical Diseases

Abstract: The Amazon rainforest has wide and unique biodiversity, which is an important source of natural productsfor the development of drugs. Neglected tropical diseases (NTDs) represent a major health problem as they affect over 1 billion people, especially vulnerable populations living in tropical and subtropical regions. Currently available drugs are generally inadequate for the majority of these diseases, thus, there is an urgent need for new treatments. The present review aims to summarize upto- date and comprehensive information on the efficacy of the Amazon plants, in treating certainneglected tropical diseases. According to the literature information, several compounds (phenolics, alkaloids, terpenoids and steroids, among others) which were isolated from plants of the Amazon forest showed in vtro activity against Leishmania sp., Trypanosoma cruzi, the parasites responsible for leishmaniasis and Chagas disease, respectively. Moreover, extracts and essential oil from certain plants were reported to have mosquito repellent and insecticidal activities against Aedes aegypti, the vector of dengue, and chikungunya. This review demonstrated that the Amazonian rainforest is endowed with pharmacologically active plants which can be used as a starting point for the development of new drugs against NTDs, such as leishmaniasis, Chagas disease, dengue, and chikungunya.

Eco-epidemiological risk factors for Japanese encephalitis in the endemic region of North East India: a hospital-based case-control study.

Japanese encephalitis (JE) has emerged as a major public health concern in North East India due to its complex eco-epidemiological risk factors. The objective of this study was to understand the various risk factors associated with JE infection in the endemic study location. A hospital-based case-control study was conducted at Jorhat Medical College and Hospital from August 2017 to September 2018. The study participants included 49 confirmed JE cases with two control arms, one consisting of non-JE acute encephalitis syndrome (AES) patients (n = 91) and the other of non-JE non-AES patients (n = 140), admitted at the same time in the pediatric and medicine wards. A predesigned, pretested, structured questionnaire was used for data collection. Univariate analysis revealed the following to be risk factors: age at onset, sex, religion, immunization status, proximity to pigs, proximity to paddy fields (<100 m), use of a mosquito net, impregnated mosquito net, mosquito repellent, and outdoor activities. Multiple logistic regression analysis identified age at onset (adjusted odds ratio [AOR], 20.900; 95% confidence interval [CI], 2.210-31.815) and proximity to pigs (AOR, 4.190; 95% CI, 1.592-11.040) as risk factors for the first control arm and proximity to paddy fields (<100 m) (AOR, 8.470; 95% CI, 2.0251-35.438) was the only risk factor found for second control arm, whereas impregnated mosquito nets (AOR, 0.082; 95% CI, 0.009-0.725) and mosquito repellent (AOR, 0.173; 95% CI, 0.052-0.575) were found to be associated with the second control arm. Age at onset, proximity to pigs, proximity to paddy fields (<100 m), impregnated mosquito nets, and mosquito repellent were the most significant risk factors for JE in the NE region to warrant public health actions.

Development of functional textile via microencapsulation of peppermint oils: a novel approach in textile finishing

PurposeThe efforts of researchers in the 21st century have been devoted to developing novel approaches to leave planet earth green for future generations. This study aims to report the synthesis of microcapsules from natural essential peppermint oil and their application to a bleached polyester and cotton (PC) blended fabric.Design/methodology/approachMicrocapsules were prepared by a complex coacervation process and applied through the conventional pad-dry-cure method. The liquid suspension of the microcapsules was examined by optical microscopy to investigate the surface morphology of the microcapsules. Scanning electron microscopy was used to examine the surface morphology of the fabric after the application of the microcapsules. The finished fabric was checked for its mosquito repellent activity at the lab scale using a standard test protocol (cage test) by inserting a human arm and hand enfolded with microcapsules treated fabric.FindingsPC fabric treated with 6% microencapsulated peppermint oil at zero wash showed 95.3% repellency against mosquitoes, and after 30 washes, the repellency was 85.8% which confirmed the durability of the developed finished fabric. The finished samples exhibited excellent air permeabilities and absorbencies.Originality/valueThis study successfully developed peppermint oil microencapsulated fabric with excellent efficacy against three mosquito species.

Review on Curcuma aromatic as an Herbal medicine

Curcuma aromatica is also a familiar Chinese herb used for treating diseases with blood stasis and has been consider as an effective anticancer herb. The rhizomes of Curcuma aromatic are used in original medicine for exterior applications on skin diseases, sprain, bruise, in snake poison, holdup the ageing process, pain relief, protecting against liver diseases and also to enhance complexion. The constituents identified in the oil is alpha-pinene, beta-pinene, camphene, 1,8-cineol, isofurano-germacrene, borneol, isoborneol, beta-curcumene, ar-curcumene, xanthorrhizol, germacrone, camphor, and curzerenone and the constituent in oil was found to differ from place to place. Bioactive compounds, counting 1, 8-cineole, ar-curcumene, ar-turmerone, β-elemene, camphor, curcumol, curdione, germacrone, linalool, xanthorrhizol, and zingiberene, from the essential oil of C. aromatica have been verified to possess anticancer properties. Usually used as an anti- inflammatory agent. It possesses a wide range of activities like Anti –inflammatory, anti-tumor, immunological effects, wound healing, anti -fungal, anti -oxidant, anti - microbial, anti-diabetic, anti-platelet and mosquito repellent activity of wild turmeric. The use of analgesic drugs, such as opiates and NSAIDs, for pain relief has been stagnated as these drugs are reported to have adverse side effects, including addiction and gastrointestinal disorders.

The fabrication and assessment of mosquito repellent cream for outdoor protection

Mosquito-borne infections like dengue, malaria, chikungunya, etc. are a nuisance and can cause profound discomfort to people. Due to the objectional side effects and toxicity associated with synthetic pyrethroids, N,N-diethyl-3-methylbenzamide (DEET), N,N-diethyl phenylacetamide (DEPA), and N,N-di ethyl benzamide (DEBA) based mosquito repellent products, we developed an essential oil (EO) based mosquito repellent cream (EO-MRC) using clove, citronella and lemongrass oil. Subsequently, a formulation characterization, bio-efficacy, and safety study of EO-MRC were carried out. Expression of Anti-OBP2A and TRPV1 proteins on mosquito head parts were studied by western blotting. In-silico screening was also conducted for the specific proteins. An FT-IR study confirmed the chemical compatibility of the EOs and excipients used in EO-MRC. The thermal behaviour of the best EOs and their mixture was characterized by thermogravimetric analysis (TGA). GC–MS examination revealed various chemical components present in EOs. Efficacy of EO-MRC was correlated with 12% N,N-diethyl benzamide (DEBA) based marketed cream (DBMC). Complete protection time (CPT) of EO-MRC was determined as 228 min. Cytotoxicity study on L-132 cell line confirmed the non-toxic nature of EO-MRC upon inhalation. Acute dermal irritation study, acute dermal dose toxicity study, and acute eye irritation study revealed the non-toxic nature of EO-MRC. Non-target toxicity study on Danio rerio confirmed EO-MRC as safer for aquatic non-target animals. A decrease in the concentration of acetylcholinesterase (AChE) was observed in transfluthrin (TNSF) exposed Wistar rats. While EO-MRC did not alter the AChE concentrations in the exposed animals. Results from western blotting confirmed that Anti-OBP2A and TRPV1 proteins were inhibited in TNSF exposed mosquitoes. Mosquitoes exposed to EO-MRC showed a similar expression pattern for Anti-OBP2A and TRPV1 as the control group. In silico study revealed eight identified compounds of the EOs play significant roles in the overall repellency property of the developed product. The study emphasizes the mosquito repellent activity of EO-MRC, which could be an effective, eco-friendly, and safer alternative to the existing synthetic repellents for personal protection against mosquitoes during field conditions.

Formulation and Evaluation of Essential Oil Encapsulated Mosquito Repellent Gel

Mosquitoes can be found in almost every country. Many mosquito repellents have been introduced to the market in order to combat them. The mosquitos, on the other hand, developed a resistance to them. Not only that, but users are experiencing a variety of known and unknown negative side effects. As a result, a poly herbal insect repellent gel has been developed in an attempt to give dependable, long-lasting, and full protection from mosquito bites by destroying them. Three essential oils were included in the formulation of the mosquito repellent gel, as well as polymers such as tween 80, span 20, Carbopol 934, and triethanolamine. They were assessed based on their actions. Spreadibility, viscosity, swelling index, and mosquito repellent activity were used to evaluate the prepared mosquito repellent gel. As acceptance criterion, all parameters received favorable responses. The rheological study and mosquito repellent activity are highly correlated. Although the results of the current trials are promising, there is still room for more pharmacokinetic research.&#x0D; Keywords: Essential Oil, Emulsion Formulations, Gel, Mosquito Repellent Activity