Search Results (57)

Background: Parasitic worm infections remain among the most prevalent and neglected health issues worldwide, affecting both humans and animals. Toxocariasis, caused by Toxocara spp., is a widespread zoonosis with significant public health and economic implications. Current anthelmintic treatments show limited efficacy, particularly against tissue-migrating larvae, underscoring the urgent need for new therapeutic options. This study aimed to evaluate the anthelmintic potential of H₁ antihistamines as repurposed drug candidates against Toxocara canis. Methods: Twenty-two H₁ antihistamines were screened for larvicidal activity against infective third-stage (L3) larvae of T. canis. Larval motility and morphology were assessed, and compounds with the highest efficacy were further investigated using density functional theory (DFT) to explore their electronic properties. Molecular docking simulations were also performed to predict interactions with T. canis β-tubulin. Results: Promethazine and rupatadine exhibited significant larvicidal effects, surpassing albendazole in reducing larval motility and inducing a distinct contorted morphology not observed in control or albendazole-treated larvae. DFT analyses suggested a strong electron-acceptor capacity, indicating a potential redox-based mechanism of action. Docking studies revealed favorable binding to the colchicine site of T. canis β-tubulin. Conclusions: This is the first report of larvicidal activity of antihistamines against T. canis, supporting their potential as repurposed therapeutic agents for the treatment of zoonotic helminthiases, particularly those caused by tissue-migrating nematodes. Full article

Here we presented the synthesis of two groups of heterocyclic benzimidazole derivatives—methanimines 4a–c and hydrazones 6a–c. In vitro biological activity screening of the compounds was performed on isolated encapsulated muscle larvae of Trichinella spiralis. All tested compounds showed higher efficacy than albendazole, with compound 4a demonstrating activity comparable to ivermectin. Structure–activity relationship (SAR) analysis revealed that methanimines 4a–c, containing a thiophene moiety, were more effective than their hydrazone counterparts, highlighting the beneficial synergy between benzimidazole and thiophene pharmacophores. However, replacing the -N=CH- linker in compound 4a with -NH-N=CH- (as in compound 6a) led to a 23% reduction in activity, suggesting that methaniamines possess superior larvicidal potency under equivalent structural conditions. The ability of the studied compounds to interfere with the tubulin polymerization was studied spectrophotometrically on purified porcine brain. Of note, the tested benzimidazoles 4a–b and 6a–b had no discernible effect on tubulin polymerization. An in silico study of the physicochemical and pharmacokinetic characteristics of the novel synthesized heterocyclic benzimidazoles showed that they were characterized by a significant degree of drug-likeness and optimal properties for antineurotrichinellosis agents. Full article

This study aimed to explore and identify soil-dwelling nematophagous fungi (NF) from the “El Texcal” Ecological Reserve in Morelos, Mexico, and evaluate their potential as biological control agents against Haemonchus contortus infective larvae (HcL3), a major parasitic threat in livestock systems. The fungi were isolated from soil using the sprinkling of soil on water agar plates. The identification of NF was achieved using morphological identification keys, which was corroborated by molecular procedures using the PCR technique in the ITS4 and ITS5 regions. The nematocidal effects occasioned by these NF were examined through their predatory activity (PA) against HcL3 on water agar plates, and additionally, the larval mortality attributed to their liquid filtrates (LFs) was assessed at three different concentrations (25, 50, and 100 mg/mL) on 96-well microtiter plates. Two NF were identified and classified as two species of Dactylellina genus, namely D. haptospora (Dh) and D. phymatopaga (Dp). The PA exhibited by these NF were 94.79% for Dh and 68.88% for Dp; while their LFs showed 27.83% mortality for Dh and 32.86% for Dp at the highest concentration assessed. While the PA was notably high, the moderate larvicidal effect of the LF suggests that their efficacy may primarily rely on direct physical interaction rather than metabolite-mediated toxicity. The high PA demonstrated by these two isolates of NF indicates that they could be effective candidates for biological control agents against HcL3. Full article

Synthetic insecticides are widely used against mosquitoes, but misuse has led to environmental and health concerns. Plant-derived alternatives, such as essential oils, seem to offer a safer option, minimizing these problems without compromising efficacy. In this study, we evaluated the essential oil from Siparuna gesnerioides (Kunth) A.DC., a Neotropical plant, for its effectiveness in controlling Aedes (Stegomyia) aegypti (Linnaeus) larvae, a major vector of human diseases. We first assessed the phytochemistry of the essential oil and used in silico approaches to predict potential physiological targets of its larvicidal activities. Selectivity assays were conducted with Belostoma anurum (Herrich-Schäffer), a non-target predatory water bug. The major constituents of S. gesnerioides essential oil were γ-elemene (45.8%) and germacrene D (43.8%). This essential oil effectively killed larvae from both susceptible and resistant mosquito strains (LC₅₀ = 0.070 μg/mL). However, such concentrations killed more than 80% of B. anurum nymphs. Molecular modeling suggested that the essential oil major components (γ-elemene and germacrene D) interact stably with mosquito acetylcholinesterases (AChEs), indicating a potential mechanism of action. Our results reinforce the potential of Siparuna essential oils in mosquito control. Nevertheless, the non-selective impact on mosquito predators, as seen with S. gesnerioides, highlights the need for caution in field applications. Full article

There is a growing need for eco-friendly methods to control disease-carrying insects. The present study aimed to investigate the larvicidal activity of methanolic extracts and their various fractions from a plant, Artemisia arborescens L., and a marine sponge, Hyrtios erectus, against the mosquito, Culex pipiens L. Crude methanolic extracts of A. arborescens and H. erectus were prepared by maceration and successive fractionation were obtained using the liquid–liquid partition of crude extracts. The larvicidal activity of the extracts and their fractions was determined according to the WHO standard method. The results revealed that the n-hexane fraction of A. arborescens exhibited the highest larvicidal activity (LC₅₀ 346.74 μg/mL), exceeding the efficacy of the crude extract and other fractions. Furthermore, the sponge’s n-hexane (LC₅₀ 68.39 μg/mL), chloroform (LC₅₀ 63.03 μg/mL), and n-butanol (LC₅₀ 71.23 μg/mL) fractions showed a significant 3.9 to 4.5 times increase in the larvicidal potency compared to its crude extract (LC₅₀ = 280.74 μg/mL). The safety of the sponge extracts was tested in the embryos of zebrafish as a non-target organism. In this regard, the crude methanolic extract and n-butanol fraction exhibited weak toxicity and chloroform fraction showed no detectable toxicity. This study suggests the H. erectus sponge as a source for developing safe natural substitutes for use in the battle against Cx. pipiens mosquito, which may help in reducing the spread of mosquito vectors and mosquito-borne diseases. Full article

Background: Among major public health problems, malaria stands out as a tropical disease caused by the Plasmodium protozoan, with mosquitoes of the Anopheles genus serving as its vectors. This disease affects a significant portion of the population, with the highest incidence in the Legal Amazon, a region responsible for 99% of cases. Although vector control strategies, such as the use of chemical insecticides, are commonly employed, mosquito resistance, environmental impacts, and risks to human health are driving the search for natural alternatives, including the application of essential oils. Objectives: This study investigates the larvicidal activity of Trattinnickia burserifolia Mart. essential oil against Anopheles darlingi. Methods: The essential oil was obtained through hydrodistillation, and its chemical composition was identified using gas chromatography–mass spectrometry. The larvicidal assay followed WHO protocols, testing oil concentrations ranging from 20 to 100 µg mL⁻¹. Results: Efficacy was evaluated after 24, 48, and 72 h to determine LC₅₀, LC₉₀, and other parameters. Chemical composition analysis revealed the presence of 40 compounds, primarily terpenes such as tricyclene, β-pinene, limonene, and α-pinene, which possess bioactive properties that contribute to vector control. The larvicidal activity test showed that LC₅₀ decreased with longer exposure times, indica ting increased efficacy over time. After 72 h, the LC₅₀ was 14.51 µg mL⁻¹, classifying the essential oil as highly effective. Conclusions: Therefore, T. burserifolia Mart. essential oil represents a promising natural alternative for malaria vector control. Full article

Background: Viral diseases including dengue, zika, chikungunya, and yellow fever remain a significant public health challenge, primarily due to the increasing resistance of these vectors, the Aedes aegypti mosquito, to conventional control methods. Objectives: Herein, a microencapsulated curcumin formulation was developed and characterized using spray-drying technology, with D-mannitol and starch as encapsulating agents. After microencapsulation, photolarvicidal tablet formulations (Formulated Curcumin Tablets—FCT) were prepared, varying the proportions of starch and pectin: FCT1 (60% starch), FCT2 (35% pectin and 25% starch), and FCT3 (42.5% pectin and 17.5% starch), while maintaining 10% curcumin and 30% D-mannitol in all formulations. The main goal was to enhance the stability and efficacy of curcumin as a photolarvicidal agent. Methods: The formulation was characterized by UV-Vis spectroscopy, confocal microscopy, thermal analysis (TG and DSC), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), and photodegradation assays under fluorescent light. Results: The photodynamic inactivation (PDI) of Ae. aegypti larvae was evaluated under white, fluorescent light exposure, and the formulation exhibited a significantly enhanced larvicidal activity compared to free curcumin, with a 57-fold reduction in LC₅₀ (LC_50-24h = 0.27 mg/L). Additionally, the most effective formulation, FCT2, maintained its residual activity for 27 days, reinforcing that curcumin microencapsulation, combined with PDI, can extend vector control. Release studies under different pH conditions confirmed a controlled release mechanism, favoring environmental stability. Conclusions: The results indicate that microencapsulated curcumin has great potential as a sustainable photoinsecticidal agent, offering stability, efficacy, and a promising alternative for managing Ae. aegypti larval populations. Full article

Dengue fever is a mosquito-borne viral infection that recently appeared in Upper Egypt. Globally, more than 50 million new infections occur annually. It currently lacks effective treatment, necessitating vector control strategies targeting Aedes aegypti. This study investigates the potential of chlorophyllin as a control agent against dengue vectors. Chlorophyllin was characterized by FTIR analysis. The singlet oxygen quantum yield was determined by comparing the luminescence intensity at 1270 nm with that of phenalenone, yielding a value of 0.18. LC₅₀ and LC₉₀ values were calculated for chlorophyllin. Its larvicidal efficacy was assessed, revealing an LC₅₀ of 0.47 ppm in controlled laboratories and 93.3 ppm in semi-field conditions, demonstrating its superior potency against Aedes aegypti compared to pheophorbide and Bacillus sphaericus. Genotoxicity was analyzed through Random Amplified Polymorphic DNA (RAPD)-PCR, and histopathological changes were documented through microscopic examination. The genotoxicity results revealed high similarity in the DNA configurations of chlorophyllin-treated larvae and healthy individuals (similarity index of 0.8), whereas pheophorbide and Bacillus sphaericus exhibited substantial genetic deviations. Histopathological analysis demonstrated severe disruptions in chlorophyllin-treated larvae’s gut epithelial cells and muscle tissues, including epithelial detachment and irregular cell shapes. These findings position chlorophyllin as a promising gut toxin larvicide for Aedes aegypti control, with a more favorable genetic safety profile than conventional chemicals. Full article

Rhamnolipids, biosurfactants synthesized from natural resources, demonstrate significant applications, including notable insecticidal efficacy against Aedes aegypti L., the primary vector for numerous arboviruses. The global spread of A. aegypti poses substantial public health challenges, requiring innovative and sustainable control strategies. This research investigates the use of andiroba (Carapa guianensis Aubl.) biomass waste as a substrate for synthesizing a rhamnolipid biosurfactant (BSAW) produced by Pseudomonas aeruginosa and evaluates its insecticidal activity against A. aegypti. The findings indicate a biosurfactant yield of 4.42 mg mL⁻¹, alongside an emulsification index approaching 60%. BSAW successfully reduced both surface and interfacial tensions to below 30 mN/m and 4 mN/m, respectively. Characterization revealed that BSAW is a di-rhamnolipid, consisting of two rhamnose units covalently linked to a saturated C₁₀ fatty acid chain. At a concentration of 1.0 mg mL⁻¹, BSAW exhibited notable larvicidal activity, leading to structural impairments and cellular dysfunctions in A. aegypti larvae while also disrupting their associated bacterial microbiota. Moreover, BSAW effectively deterred oviposition in adult mosquitoes. These findings underscore BSAW’s potential to compromise various developmental stages of A. aegypti, supporting integrated arbovirus management approaches. Furthermore, this research emphasizes the feasibility of utilizing agro-industrial waste as substrates for microbial rhamnolipid production. Full article

For communities without access to uninterrupted, piped water, household water storage (HWS) practices can lead to adverse public health outcomes caused by water degradation and mosquito proliferation. With over 700,000 deaths caused by vector-borne diseases annually, the objective of this study was to determine whether water disinfectants, at concentrations deemed safe for human consumption and beneficial for water treatment, are effective in reducing the emergence of adult mosquitoes that transmit disease. Laboratory bioassays, designed to resemble the context of treating HWS containers, were conducted to assess the larvicidal effects of chemicals at concentrations below regulatory limits for drinking water: silver (20, 40, 80 μg/L Ag), copper (300, 600, 1200 μg/L Cu), and chlorine (500, 1000, 2000 ug/L free chlorine). The water disinfectants demonstrated the ability to significantly reduce the population of juvenile Ae. aegypti. Sodium hypochlorite was found to be the most effective in decreasing the survival rate of late first instar larvae, while silver nitrate exhibited the highest effectiveness in inhibiting the emergence of late third instar larvae. Ultimately, this study highlights the potential of an integrated approach to Water, Sanitation, and Health (WASH) solutions with vector control management. Full article

New alternatives for controlling resistant populations of gastrointestinal nematodes are being studied, including the use of plant compounds and biological control with nematophagous fungi. The objective of this study was to evaluate the in vitro anthelmintic effect of linalool and its association with the fungus Duddingtonia flagrans (isolated AC001) in controlling gastrointestinal nematodes in sheep. The ovicidal activity of linalool was assessed via the Egg Hatch Test (EHT), and the larvicidal activity of linalool, alone and in combination with D. flagrans conidia, was evaluated via the Larval Motility Inhibition Test (LMIT) on infective larvae (L3). In the EHT, 100% inhibition occurred (at 1.25 and 2.5 mg/mL), with an LC50 of 0.49 mg/mL. In the LMIT, linalool alone inhibited 100% of larval motility (at 4% and 8%), with an LC50 of 0.42% or 4.2 mg/mL. In the combination of linalool with D. flagrans, there was a significant reduction in larvae, starting at 24 h, with 100% reduction after 14 days, thus being more effective in reducing L3 compared to the use of the fungus alone. It is concluded that linalool exhibits ovicidal and larvicidal activity, and its association with D. flagrans enhances the fungal predation capacity and potentiates anthelmintic efficacy. Full article

Background/Objectives: Arboviruses, transmitted by mosquitoes like Aedes aegypti, pose significant public health challenges globally, particularly in tropical regions. The rapid spread and adaptation of viruses such as Dengue, Zika, and Chikungunya have emphasized the need for innovative control methods. Essential oils from plants, such as Pectis brevipedunculata (Gardner) Sch.Bip. (Pb), have emerged as potential alternatives to conventional insecticides. Methods: In this work, we developed an eco-friendly nanogel using a low-energy, solvent-free method, incorporating the copolymer F127 and Carbopol 974p, enriched with a high concentration of essential oil from Pb (EOPb). The resulting nanogel displayed excellent physical stability, maintained under varying temperature conditions. Characterization techniques, including FTIR and DLS, confirmed the stable incorporation of EOPb within the nanogel matrix. Results: The in vitro assays against Aedes aegypti larvae revealed that at 500 $\mathsf{\mu }$g/mL, the mortality rates were 96.0% ± 7.0 after 24 h and 100.0% ± 0.0 after 48 h. The positive control group treated with temefos, achieved 100% mortality at both time points, validating the experimental conditions and providing a benchmark for assessing the efficacy of the nGF2002Pb nanogel. Conclusions: These results indicate that nGF2002Pb demonstrates a pronounced concentration-dependent larvicidal effect against Aedes aegypti, offering an innovative and sustainable approach to arbovirus vector control. Full article

Infectious diseases, including vector-borne and antibiotic-resistant infections, present significant global health challenges, necessitating the exploration of natural alternatives for disease control. In this study, we investigated the essential oil (EO) profile as well as larvicidal and antibacterial properties of two wild Apiaceae species used in Algeria: Daucus carota L. (DCEO) and Foeniculum vulgare Mill. (FVEO). EO was extracted from the aerial parts by steam distillation and analyzed using Gas Chromatography Mass Spectrometry (GC/MS). Major constituents identified in DCEO were geranyl acetate (50.07%) and elemicin (10.77%), while FVEO contained estragole (24.93%), fenchone (20.20%), and α-phellandrene (17.96%). Both EOs were highly effective towards Culex pipiens larvae, with low LC₅₀ values of 30.6 ± 1.06 ppm for DCEO and 34.7 ± 1.06 ppm for FVEO, indicating their potential as bioinsecticides due to their bioactivity and bioavailability. Additionally, the two Eos demonstrated moderate antibacterial efficacy against gram-positive bacteria, Staphylococcus aureus ATCC 25923 and Staphylococcus aureus MRSA ATCC 43300, respectively, with DCEO showing MIC values of 10 and 20 mg/mL, respectively, and FVEO exhibiting MIC values > 20 mg/mL. However, both EOs showed limited effectiveness against gram-negative bacteria, Escherichia coli ATCC 25922 and Klebsiella pneumonia ATCC 700603. These results highlight the potential applications of DCEO and FVEO as natural bioinsecticides and antibacterial agents, offering promising avenues for further research and development in pest control and food preservation. Full article

The synthesis of nanoparticles utilizing green techniques is becoming increasingly important due to its low cost, biocompatibility, high productivity, and eco-friendliness. Herein, the current work focused on the biosynthesis, characterization, and biological applications of zinc oxide nanoparticles (ZnO-NPs) from Anabasis articulata, including antioxidant anticancer and larvicidal properties, as well as modifications to the phytochemical ingredients. Hence, the tannin, phenolic, and flavonoid concentrations of the produced nanoparticle samples were lower than those of the original aqueous extract. When compared to the results of ascorbic acid (12.78 mg/mL), the produced extract of A. articulata and its zinc nanoparticles showed remarkable efficacy as antioxidant agents with IC₅₀ values of 27.48 and 69.53 mg/mL, respectively. A normal lung fibroblast cell line (WI-38) and three tumor cells were used to test the compounds’ anticancer properties. With an IC₅₀ of 21.19 µg/mL, the ZnO-NPs of A. articulata showed the greatest cytotoxicity against HePG-2 cell lines. Additionally, A. articulata zinc nanoparticles showed significant cytotoxicity against MCF-7 and PC3 tumor cell lines, with IC₅₀ values of 30.91 and 49.32 µg/mL. The biogenic ZnO-NPs had LC₅₀ and LC₉₀ values of 13.64 and 26.23 mg/L, respectively, and are very effective against Aedes aegypti larval instar (III). Additionally, the percentages of larval mortality increased from 28.61% at 5 ppm to 84.69% at 25 ppm after 24 h post-treatment. The overall results of this study point to the potential of A. articulata as a substitute biological agent for potential therapeutic/leutic uses in the medical domains and for preventing the proliferation of malarial vector insects. Full article

Solanum surattense Burm. f. is a significant member of the Solanaceae family, and the Solanum genus is renowned for its traditional medicinal uses and bioactive potential. This systematic review adheres to PRISMA methodology, analyzing scientific publications between 1753 and 2023 from B-on, Google Scholar, PubMed, Science Direct, and Web of Science, aiming to provide comprehensive and updated information on the distribution, ethnomedicinal uses, chemical constituents, and pharmacological activities of S. surattense, highlighting its potential as a source of herbal drugs. Ethnomedicinally, this species is important to treat skin diseases, piles complications, and toothache. The fruit was found to be the most used part of this plant (25%), together with the whole plant (22%) used to treat different ailments, and its decoction was found to be the most preferable mode of herbal drug preparation. A total of 338 metabolites of various chemical classes were isolated from S. surattense, including 137 (40.53%) terpenoids, 56 (16.56%) phenol derivatives, and 52 (15.38%) lipids. Mixtures of different parts of this plant in water–ethanol have shown in vitro and/or in vivo antioxidant, anti-inflammatory, antimicrobial, anti-tumoral, hepatoprotective, and larvicidal activities. Among the metabolites, 51 were identified and biologically tested, presenting antioxidant, anti-inflammatory, and antitumoral as the most reported activities. Clinical trials in humans made with the whole plant extract showed its efficacy as an anti-asthmatic agent. Mostly steroidal alkaloids and triterpenoids, such as solamargine, solanidine, solasodine, solasonine, tomatidine, xanthosaponin A–B, dioscin, lupeol, and stigmasterol are biologically the most active metabolites with high potency that reflects the new and high potential of this species as a novel source of herbal medicines. More experimental studies and a deeper understanding of this plant must be conducted to ensure its use as a source of raw materials for pharmaceutical use. Full article