Search

The rapid spread of the drug-resistance among microbes has made the treatment of infections a problematic task. Microbial biofilms are complex aggregations of microbial cells encapsulated in a polymeric matrix that further worsens the treatment of microbial infections. In this study, ZnONPs were synthesized via green route using the aqueous tuber extract of Drynaria quercifolia. Biophysical property of ZnONPs was characterized by UV-vis spectroscopy, XRD, FTIR, SEM with EDS, and HR-TEM analyses and was found to have a size of 10 nm. Synthesized ZnNOPs demonstrated good antimicrobial activity against bacterial (B. cereus, S. typhi, and E. coli) and fungal (A. flavus and C. albicans) strains. Subsequently, the ZnONPs also exhibited excellent antioxidant property DPPH (78.52%), ABTS assay (70.18%), and hydroxyl scavenging assay (77.34%) at 100 μg/ml concentration. The biofilm inhibitory activity against E. coli, B. cereus, and S. typhi was recorded. Additionally, we also evaluated the larvicidal activity of ZnONPs against Cx. quinquefasciatus and recorded LC50 value of 130.725 μg/ml. Histopathology studies revealed that the region of hind and mid intestine, epithelial cells, and cortex were affected severely upon the treatment with ZnONPs. Photocatalytic activity was tested on crystal violet for dye degradation. Nearly complete degradation of the tested dye occurred within 72 min. The study suggests that green-synthesized ZnONPs could be a preferred alternative for various biomedical applications and contribute to the eventual elimination of environmental pollutants in the near future. [ABSTRACT FROM AUTHOR]

In this study, veratrylidenehydrazide was isolated from Wedelia biflora, and compounds (1a, 2a, and 3a–j) were synthesised to evaluate their larvicidal and antifeedant activities. Veratrylidenehydrazide 1a was verified using GC‐MS. The veratrylidenehydrazide analogues 2a and 3a–j were synthesised via a condensation method with yield range 71%–92%. The compounds (1a, 2a, and 3a–j) were synthesised and characterised through FT–IR, 1H NMR, 13C NMR, mass spectrometry, and elemental analysis. Veratrylidenehydrazide 1a was verified using GC‐MS analysis. Natural veratrylidenehydrazide compound 1a and the synthesised veratrylidenehydrazide analogues (2a, 3a–j) were screened for larvicidal activity against Culex quinquefasciatus. The larvicidal activity of compound 3g was found to be highly active, while low toxicity was observed against Oreochromis mossambicus nontarget aquatic species compared to natural veratrylidenehydrazide. Compound 3g exhibited a higher binding affinity (−8.8 kcal/mol) compared to standard of temephos (−4.5 kcal/mol), equipotential binding affinity against permethrin (−9.1 kcal/mol), and diflubenzuron (−8.5 kcal/mol). Lead molecules have larvicidal properties, and their use as insecticides makes them important. [ABSTRACT FROM AUTHOR]

The synthesis of CuO/C nanocomposites was fabricated using an uncomplicated and eco-friendly method by Cyperus rotundus (C. rotundus) leaf extract. The formation of nanocomposites and their size were optimized with various factors, such as operational parameters, viz. exposure time, temperature, and concentration of the precursor, by response surface methodology (RSM). The effects of the synthesis of CuO/C nanocomposite samples and their characterization by various analytical techniques such as UV, XRD, XPS, EDX, SEM, and TEM have been reviewed and confirmed. The XRD patterns revealed that the biosynthesized CuO/C sample exhibited a monoclinic and crystalline structure. Moreover, the elements available in nanocomposites were determined as Cu 2p, O 1 s, and C1s using XPS analysis. The TEM pictures reveal the morphology of the nanocomposites as spherical in form, with an average size of 30 nm. Additionally, synthesized CuO/C nanocomposites were examined for toxic effects on the mortality of two-winged insect larvae, and they were absolutely found to be extremely active and considerably kill larvae. The molecular docking study found that the nanocomposites were able to bind to the target protein with high affinity, which suggests that they are likely to be effective larvicidal agents. Our existing analysis findings can open up a replacement void for the larvicidal analysis exploiting biosynthesized nanocomposites. [ABSTRACT FROM AUTHOR]

Mosquitoes are rapidly advancing as vectors of several severe diseases. The increasing resistance of mosquitoes and the environmental harm caused by insecticides pose significant challenges for eradicating mosquito vectors. In this study, 18 plant extracts were tested for larvicidal properties against Aedes aegypti, Culex quinquefasciatus, and Anopheles stephensi larvae. Phyllanthus niruri (Pn) showed enhanced larvicidal activity in both laboratory and field trials. The biosynthesis of silver nanoparticles (AgNPs) using Pn leaf methanol extract (Pn-LME) was confirmed by UV-visible spectroscopy, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and Fourier-transform infrared spectroscopy. Among various concentrations, 3 mM AgNPs exhibited significant LC90 values of 0.83, 1.46, and 9.11 ppm compared to 9.25, 93.48, and 14.60 ppm of Pn-LME against A. stephensi, C. quinquefasciatus, and A. aegypti, respectively. This indicates the high mortality of mosquito vectors at low AgNP concentrations. Additionally, Pn-AgNPs showed enhanced antibacterial activity and no cytotoxicity in normal fibroblast cells (L929). Field trials demonstrated a 98.70% decrease in mosquito larval density at A. stephensi breeding sites, a 96.55% reduction at C. quinquefasciatus sites, and a 97.85% reduction at Ae. aegypti sites. This study presents an eco-friendly and cost-effective AgNP bio-pesticide synthesized from Pn leaves for controlling and preventing the transmission of filarial, dengue, and malaria vectors.

Abstract Mosquito-borne diseases, such as malaria, dengue, and Zika, pose major public health challenges globally, affecting millions of people. The growing resistance of mosquito populations to synthetic insecticides underscores the critical need for effective and environmentally friendly larvicides. Although chemical pesticides can initially be effective, they often lead to negative environmental consequences and health hazards for non-target species, including humans. This study aimed to evaluate the larvicidal effects of Trachyspermum ammi essential oil and Delphinium speciosum extract on the larvae of three major mosquito species: Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. Mosquito larvae of Ae. aegypti, An. stephensi, and Cx. quinquefasciatus were reared under controlled laboratory conditions. The larvicidal activity of T. ammi essential oil and D. speciosum extract was evaluated through standard bioassays, using various concentrations of essential oils (10, 20, 40, 80, and 160 ppm) and extracts (160, 320, 640, 1280, and 2560 ppm) to determine the lethal concentration (LC50) values after 24 h of exposure. Fresh plant materials were collected, with the essential oil extracted via hydro-distillation, and the extract prepared using methanol solvent extraction. The chemical composition of T. ammi essential oil was examined using gas chromatography-mass spectrometry (GC-MS). Additionally, the preliminary analysis of the chemical compounds in D. speciosum extract was carried out using thin layer chromatography (TLC) and nuclear magnetic resonance spectroscopy (NMR) techniques. The results indicated that the essential oil of T. ammi exhibited more effective larvicidal activity compared to the D. speciosum extract. Specifically, the essential oil demonstrated LC50 values of 18 ppm for Cx. quinquefasciatus and 19 ppm for Ae. aegypti. In contrast, the D. speciosum extract showed the strongest larvicidal effect against An. stephensi, with an LC50 of 517 ppm. Concentrations of 40 ppm of the essential oil and 1280 ppm of the extract resulted in 100% mortality across all three species. Both the essential oil of T. ammi and the D. speciosum extract exhibited concentration-dependent larvicidal activity, and these results were statistically significant (p

Gold nanoparticles (GNPs) are commonly utilized in biomedical science, but the potential application of green synthesized herb-based GNPs is elusive. Here, aqueous extracts of Ammannia baccifera were used to synthesize GNPs, and the properties of green synthesized GNPs were analyzed. Our results showed that these GNPs possessed larvicidal activity for Anopheles subpictus and Culex Quinquefasciatus, and antimicrobial activity for Escherichia coli, Staphylococcus aureus, Klebsiella pneumoniae, and Bacillus subtilis. A rising dose of GNPs in zebrafish followed an increasing Au accumulation. Furthermore, the expression levels of immune-related genes were dramatically activated after exposure to these GNPs. To our knowledge, this is the first report on the potential application of the GNPs derived from A. baccifera extract. [ABSTRACT FROM AUTHOR]

The present study was carried out for the first time in Morocco to valorise plant species of the Artemisia genus. Its aim was to evaluate the larvicidal activity of essential oils from six Artemisia plants (A. herba alba, A. absinthium, A. campestris L., A. negrei, A. pontica, and A. arborescens) against Culex pipiens mosquitoes, which are recognised as potential vectors of West Nile virus. Bioinsecticides derived from EOs have shown promise as effective mosquito control agents. The EOs were analysed using GC–MS and GC‐FID and were obtained by hydrodistillation from the aerial parts of the plants. Besides, the experiment was carried out according to the standard WHO protocol. Thujone and camphor were identified as the predominant compounds in all six Artemisia plants. A. herba alba demonstrated the highest larvicidal activity with LC50 and LC90 values of 4.85 and 15.39 μg/mL, respectively. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were employed to explore the correlation between major EO compounds and larvicidal efficacy. The results suggest that these findings could pave the way for the development of tailored biocides that specifically target important disease vectors. [ABSTRACT FROM AUTHOR]

Purpose: Fall armyworm (FAW) Spodoptera frugiperda J.E Smith is an invasive pest of maize crops that has been recently reported in Pakistan (2019). Synthetic insecticides are the main choice of local farmers to control this deadly pest, but with continuous use of these pesticides health and environmental issues have arisen, which demands an alternative control measure. Considering this pest’s significance, this study was conducted to determine the potentiality of Guava (Psidium guajava L.) against the third instar larvae of S. frugiperda; which is considered an effective repellent effect. Research Method: The P. guajava leaves were extracted with methanol, ethyl acetate, n-hexane, and chloroform; each extract was prepared at different concentrations of 125, 250, 500, and 1000 ppm. Later, the larval mortality was recorded at different intervals of 24, 48, 72, and 96 hrs, and antifeedant activity at 24 hrs. Findings: The highest mortality of 92.86% was observed on methanol extract at 1000ppm after 96 hrs. The mortality on all crude extracts and at every concentration increased at different intervals of the observation and reached the maximum at 96 hrs. However, the LC50 and LC90 values of 154.77 and 865.3ppm after 96 hrs were recorded in methanol. Similarly, the highest antifeedant activity was 87.5% recorded in methanol at 1000ppm, and the lowest antifeedant activity of 22.58% was noted in chloroform extracts at 125ppm concentration. It showed that the antifeedant activity relied on a concentrated dose; meanwhile, the P. guajava with methanol crude extracts successfully stopped the feeding activity of S. frugiperda. Originality/ Value: Therefore, based on the obtained results, the P. guajava leaf extracts are highly recommended, particularly for their extraction with methanol and n-hexane which showed the highest larval mortality and antifeedant activity of S. frugiperda. [ABSTRACT FROM AUTHOR]

Environmental pollution, being a major concern worldwide, needs a unique and ecofriendly solution. To answer this, researchers are aiming in utilizing plant extracts for the synthesis of nanoparticles. These NPs synthesized using plant extracts provide a potential, environmentally benign technique for biological and photocatalytic applications. Especially, plant leaf extracts have been safe, inexpensive, and eco-friendly materials for the production of nanoparticles in a greener way. In this work, zinc ferrite nanoparticles (ZnFe2O4 NPs) were prepared using Nyctanthes arbor-tristis leaf extract by hydrothermal method, and its biological and photocatalytic properties were assessed. The synthesized ZnFe2O4 NPs were characterized using powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared spectroscopy (FT-IR). X-ray diffraction confirmed the arrangement of the fcc crystal structure of the nanoparticles and that some organic substances were encapsulated within the zinc ferrite. According to the SEM analysis, the resulting nanoparticles got agglomerated and spherical in shape. The ZnFe2O4 nanoparticles are in their pure form, and all of their elemental compositions were shown by the energy-dispersive X-ray analysis (EDAX) spectrum. The FTIR results revealed that the produced nanoparticles contained distinctive functional groups. Fluorescence spectroscopy was used to examine the binding affinities between bovine serum albumin (BSA) and ZnFe2O4 nanoparticles in terms of protein binding, stability, and conformation. The interaction between BSA and ZnFe2O4 NPs was examined using steady-state and time-resolved fluorescence measurements, and it was evident that static quenching occurred. The ability of ZnFe2O4 nanoparticles to kill Culex quinquefasciatus (C. quinquefasciatus) larvae was evaluated. The synthesized NPs demonstrated a noteworthy toxic effect against the fourth instar larvae of C. quinquefasciatus with LC50 values of 43.529 µg/mL and LC90 values of 276.867 µg/mL. This study revealed the toxicity of green synthesized ZnFe2O4 NPs on mosquito larvae, proving that these NPs are good and effective larvicides. Furthermore, the ZnFe2O4 NPs were utilized for dye degradation of methylene blue under visible light treatment and achieved 99.5% degradation. [ABSTRACT FROM AUTHOR]

The dengue vector Aedes aegypti is exceptionally threatening worldwide as it causes a primary viral disease (dengue), even though the vector species has other viral loads. This study was aimed at investigating the Annona reticulata extract with respect to the larvicidal activity against the 4th instar larvae of Aedes aegypti, the toxicity on a non-target aquatic organism (Chironomus costatus), and the biochemical marker enzymes in the mosquito larvae. Among various solvent tested, ethyl acetate as extraction solvent showed the highest mortality (100%) at 200 ppm against Aedes aegypti with no adverse effect on the non-target aquatic organism tested. Besides, the ethyl acetate extract showed significant inhibition of acetylcholinesterase (19%), α- and β-carboxylesterases (47.2 & 70.3%, respectively), glutathione S-transferase (35.2%), and alkaline phosphatase (22.3%). Moreover, the protein (13.7%) and acid phosphatase (11.2%) were reduced without being significant in the quantitative analyses. In qualitative analyses, we also observed that all enzyme patterns showed differential expression upon exposure to the ethyl acetate extract against the 4th instar larvae of Aedes aegypti at a lethal concentration (LC50: 72.5 ppm) for 24 h. These findings precisely showed that the Annona reticulata active extract (using ethyl acetate) can be used as an alternative in pest and vector control management contributing towards not spreading infectious diseases. [ABSTRACT FROM AUTHOR]

Traditional methods of pest control are not able to prevent crop damage due to devastating pests. Therefore, through nanobiotechnology nano-bio pesticides and conjugated nanoparticles are produced as a pest control agent. The present work focused on the synthesis, characterization of silver nanoparticles (AgNPs) using Ocimum tenuiflorum leave extract and its larvicidal activity against Helicoverpa armigera. AgNPs were characterized by UV–Vis spectral analysis, indicated an absorbance of 4.695 at 560 nm. Moreover, Scanning Electron Microscope and X-ray Powder Diffraction showed that particles were spherical, ranging from 10 nm to 65 nm. The larvae of H. armigera were provided with an artificial diet with AgNPs coating of 0.25%, 0.5%, 0.75%, and 100% pure concentration. After 24 h, a dose response relationship in mortality was found maximum in pure AgNPs treated group, 83.33% and 75% in 0.75% treated group and 0.5% treated group, respectively. While the least mortality of 50% was observed in the 0.25%, AgNPs treated group. The LC50 calculated was 20.33 µL for AgNPs. It can be concluded that silver-nanoparticles possess a larvicidal effect. Furthermore, the biosynthesis of these particles is an efficient and profitable approach. [ABSTRACT FROM AUTHOR]

Coldeniaprocumbens leaf extract assisted green synthesis of gadolinium-doped bismuth oxide nanoparticles (Gd-Bi2O3NPs) was demonstrated. Electron microscopic analysis indicated that the Gd-Bi2O3 has nanoflake-like shape with a narrow size distribution of 20–30 nm. FT-IR and XRD analysis confirmed the doping of Gd-ions into Bi2O3 crystal structure. The UV–vis spectral investigation was carried to know the characteristic absorbance peaks and the band gap of Gd-Bi2O3 samples. The antibacterial activity of Gd-Bi2O3 samples was evaluated against Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae and Enterococcus faecalis. The larvicidal activity of Gd-Bi2O3 samples was also evaluated against the mosquito larvae of Aedesaegypti and Aedesalbopictus. Furthermore, the photocatalytic potential of Gd-Bi2O3 samples has been evaluated using malachite green (MG) and methylene blue (MB) dyes under visible light radiation. The green Gd-Bi2O3 samples displayed potent antibacterial, larvicidal, and photocatalytic activities, making them a promising candidate for environmental remediation applications.

Utilizing synthetic insecticides to control mosquito populations has many adverse side effects as they can cause environmental pollution and insecticide resistance. Therefore, the search for eco-friendly and effective mosquito control agents has led to the exploration of plant extracts with larvicidal efficacy. In this study, we aimed to explore the larvicidal activity of four Egyptian plant extracts: Rosmarinus officinalis, Melissa officinalis, Cichorium intybus, and Beta vulgaris var. cicla against Culex pipiens and to identify the chemical constituents present in the active extracts. The methanolic extracts of the four plants were prepared and tested against the third instar larvae of C. pipiens using a standard method. The lethal concentrations (LC50 and LC90) were calculated using probit analysis. The active extracts were subjected to ultra-performance liquid chromatography-mass spectroscopy (UPLC-MS/MS) analysis and the data were processed using the global natural products social molecular networking (GNPS) platform to generate molecular networks and identify the compounds based on spectral similarity and database matching. The methanolic extracts of R. officinalis L. and M. officinalis L. had the highest larvicidal activity, where LC50 values were 9.795 and 26.505 μg/mL, respectively. Their exposure caused a high mortality rate and disrupted the biochemical and physiological parameters (total carbohydrates, total lipids, total protein, acetylcholinesterase (AChE), and glutathione S-transferase (GST) in the body of C. pipiens when compared with Cichorium intybus (Chicory) and Beta vulgaris var. cicla (Chard). The UPLC-MS/MS analysis with the aid of the GNPS platform, revealed the presence of 23 and 41 metabolites from R. officinalis L. and M. officinalis L., respectively. The identified metabolites may act as larvicidal agents by interfering with the physiological or biochemical processes of the mosquito larvae. Overall, the findings suggest that the methanolic extracts of R. officinalis and M. officinalis are potential sources of natural larvicides for mosquito control.

Common household mosquitoes are a major public nuisance, and mosquito-borne diseases are the greatest threat to public health. In the current situation, it would be ideal to control mosquito populations without harming the environment. The present study aims to evaluate the mosquitocidal efficacy of fractions and the active principle niloticin isolated from the leaves of Limonia acidissima Linn. against the life stages of Culex quinquefasciatus Say mosquitoes. The concentrations used to screen the fractions were 10.0, 7.5, 5.0, and 2.5 ppm and the active compound niloticin was tested at concentrations of 2.0, 1.5, 1.0, and 0.5 ppm on the larval (L3) and pupal stages of Cx. quinquefasciatus. The results showed that fraction-8 recorded the highest mosquitocidal activity, and the lethality results (LC50) after 24 hours were 3.44 ppm for larvae and 5.14 ppm for pupae of Cx. quinquefasciatus, respectively. Similarly, LC50 of niloticin at 24 hours were 0.42 ppm for larvae and 0.51 ppm for pupae of Cx. quinquefasciatus, respectively. In addition, at a concentration of 2.0 ppm, niloticin showed an ovicidal activity of 94.4% and a deterrent effect on oviposition of 100% and exhibited considerable growth disruption. In conclusion, the results indicate that niloticin can be used for vector mosquito control. [ABSTRACT FROM AUTHOR]

Simple Summary: The essential oil (EO) of Citrus reticulata Blanco cv. Chachiensis (Chachi) exhibited significant larvicidal activity. The EO from semi-mature fruits and its main components were able to control mosquitoes by effectively inhibiting acetylcholinesterase and three detoxification enzymes and significantly altering the diversity of the internal microbiota in mosquitoes. The overuse of synthetic insecticides has led to various negative consequences, including insecticide resistance, environmental pollution, and harm to public health. This may be ameliorated by using insecticides derived from botanical sources. The primary objective of this study was to evaluate the anti-mosquito activity of the essential oil (EO) of Citrus reticulata Blanco cv. Chachiensis (Chachi) (referred to as CRB) at immature, semi-mature, and mature stages. The chemical compositions of the CRB EO were analyzed using GC-MS. The main components were identified to be D-limonene and γ-terpinene. The contents of D-limonene at the immature, semi-mature, and mature stages were 62.35%, 76.72%, and 73.15%, respectively; the corresponding contents of γ-terpinene were 14.26%, 11.04%, and 11.27%, respectively. In addition, the corresponding contents of a characteristic component, methyl 2-aminobenzoate, were 4.95%, 1.93%, and 2.15%, respectively. CRB EO exhibited significant larvicidal activity against Aedes albopictus (Ae. albopictus, Diptera: Culicidae), with the 50% lethal doses being 65.32, 61.47, and 65.91 mg/L for immature, semi-mature, and mature CRB EO, respectively. CRB EO was able to inhibit acetylcholinesterase and three detoxification enzymes, significantly reduce the diversity of internal microbiota in mosquitoes, and decrease the relative abundance of core species within the microbiota. The present results may provide novel insights into the utilization of plant-derived essential oils in anti-mosquitoes. [ABSTRACT FROM AUTHOR]

Plant extracts and essential oils can be alternative environmentally friendly agents to combat pathogenic microbes and malaria vectors. Myrrh is an aromatic oligum resin that is extracted from the stem of Commiphora spp. It is used in medicine as an insecticide, cytotoxic, and aromatic. The current study assessed the effect of Commiphora myrrha resin extracts on the biological potency of the third larval stage of Aedes aegypti, as well as its antioxidant and cytotoxic properties against two types of tumor cells (HepG-2 and Hela cell lines). It also used GC–MS to determine the chemical composition of the C. myrrha resin extracts. Fifty components from the extracted plant were tentatively identified using the GC–MS method, with curzerene (33.57%) typically listed as the primary ingredient, but other compounds also make up a significant portion of the mixture, including 1-Methoxy-3,4,5,7-tetramethylnaphthalene (15.50%), β-Elemene (5.80%), 2-Methoxyfuranodiene (5.42%), 2-Isopropyl-4,7-Dimethyl-1-Naphthol (4.71%), and germacrene B (4.35%). The resin extracts obtained from C. myrrha exhibited significant efficacy in DPPH antioxidant activity, as evidenced by an IC50 value of 26.86 mg/L and a radical scavenging activity percentage of 75.06%. The 50% methanol extract derived from C. myrrha resins exhibited heightened potential for anticancer activity. It demonstrated substantial cytotoxicity against HepG-2 and Hela cells, with IC50 values of 39.73 and 29.41 µg mL−1, respectively. Notably, the extract showed non-cytotoxic activity against WI-38 normal cells, with an IC50 value exceeding 100 µg mL−1. Moreover, the selectivity index for HepG-2 cancer cells (2.52) was lower compared to Hela cancer cells (3.40). Additionally, MeOH resin extracts were more efficient against the different growth stages of the mosquito A. aegypti, with lower LC50, LC90, and LC95 values of 251.83, 923.76, and 1293.35 mg/L, respectively. In comparison to untreated groups (1454 eggs/10 females), the average daily number of eggs deposited (424 eggs/L) decreases at higher doses (1000 mg/L). Finally, we advise continued study into the possible use of C. myrrha resins against additional pests that have medical and veterinary value, and novel chemicals from this extract should be isolated and purified for use in medicines. [ABSTRACT FROM AUTHOR]

Introduction: Pomegranate (Punica granatum L.) peels are rich in various bioactive compounds. Characterization of these compounds is crucial for the utilization of peel waste in industrial processing. Objective: The study aimed (1) to establish and compare the metabolic profiles of the peel of seven pomegranate cultivars and (2) to identify bioactive compounds contributing to the larvicidal activity against the third instar larvae of Culex pipiens. Materials and Methods: UPLC‐ESI‐MS/MS was utilized to analyze peel methanol extracts of different pomegranate cultivars. The larvicidal activity was determined by calculating the larval mortality among the third instar larvae of C. pipiens. Multivariate data analysis was conducted to identify the metabolites that exhibited a larvicidal effect. Results: A total of 24 metabolites, including hydrolyzable tannins, flavonoids, and alkaloids, were tentatively identified in both negative and positive ionization modes. The extract of cultivar 'Black' exhibited the most potent larvicidal effect with LC50 values of 185.15, 156.84, and 138.12 ppm/mL after 24, 48, and 72 h of treatment, respectively. By applying chemometric techniques, the larvicidal activity could be directly correlated to the bioactive compounds punicalagin, quercetin‐O‐rhamnoside, quercetin‐O‐pentoside, and galloyl‐HHDP‐glucose. Conclusion: The present study implemented UPLC‐ESI‐MS/MS and chemometric techniques as potential tools for metabolomics analysis and differentiation between peels of different pomegranate cultivars. In addition, cultivar 'Black' extract could be a promising natural insecticide against mosquitoes since it is rich in bioactive compounds with larvicidal activity. In this study, the phytochemical profiles of the peel methanol extracts of different pomegranate cultivars were determined using a UPLC‐ESI‐MS/MS method. A total of 24 metabolites belonging to hydrolyzable tannins, flavonoids, and alkaloids were tentatively identified. Furthermore, the larvicidal activity of the peel methanol extracts was determined against the third instar larvae of Culex pipiens. Black cultivar extract exhibited the most potent larvicidal effect. Moreover, prediction of the metabolites having larvicidal effect was investigated based on LC‐MS and multivariate data analysis. [ABSTRACT FROM AUTHOR]

The present study was aimed to test the efficacy of Leptogium marginellum (Lm) extract and synthesized silver nanoparticles (AgNP's) against mosquito larvae. The synthesized LmAgNP's was measured for its Surface Plasmon Resonance and the peak was observed at 428nm. FTIR results recorded a downward shift of absorbance band between 450-4000 cm-1 indicated the formation of Lm AgNP's which are spherically shaped with a size range from 150-200 nm confirmed using FESEM. Further, XRD analysis demonstrated LmAgNP's are highly crystalline and exhibit a cubic, face centered lattice with characteristic (111), (200), (220) and (222) orientation. The bio-reduction of silver ions in solution was monitored by EDX. The zeta potential value was found to be -3.08 mV representing AgNP's were highly stable. Radical scavenging results revealed that the extracts and AgNP's demonstrated potent scavenging ability evidenced by DPPH, FRAP and H2O2 radical assay. Lm fractions and Lm AgNP's exhibited dose dependent larval mortality, highest mortality was observed in ethylacetate fraction against Anopheles stephensi (ICc50=34.66; IC90=158.647), followed by Culex quinquefasciatus (ICc50=40.085; IC90=213.777) and Aedes aegypti (IC50=70.673; IC90=248.836). Larvae treated with LmAgNP's at different concentration represented potent mortality but at 500 ppm concentration demonstrated significant mortality with 88, 94.4, 98.4% mortality with highest activity against Anopheles stephensi (ICc50=47.41) followed by Aedes aegypti and Culex quinquefasciatus (IC50=71.66; IC50=74.44). Based on the present findings it is suggested that the fractions and AgNP's of Lm is effective in inhibiting the growth of mosquito larvae. [ABSTRACT FROM AUTHOR]

The present study assessed the larvicidal action of Garcinia mangostana pericarp against Culex pipiens larvae. Hexane extract was prepared from the fruit. The secondary metabolites were identified using phytochemical analysis and gas chromatography-mass spectrometry (GC-MS). The cytotoxic effect was also evaluated using normal human umbilical endothelial cells (HUV-EC). The larvicidal assay was performed on the third instar stage as recommended by WHO. The phytochemical analysis showed the presence of alkaloids, sterols, and phenolic compounds. The GC-MS analysis revealed the presence of 5 compounds, of which a-Copaene constituted 61.95% of the extract. The hexane extract showed good larvicidal activity, with an LC50 = 33.9 μg mL-1 and LC90 = 64.1 μg/mL at 24 h post exposure. The midgut sections of treated larvae showed morphological alterations such as microvilli damage, loss of nuclei, and peritrophic membrane degeneration. The extract also showed high cytotoxic activity against HUV-EC cells, with an LC50 of 19.8 μg/mL. The results indicated that G. mangostana has larvicidal activity against Cx. pipiens larvae. Further investigation can be done to confirm the larvicidal potential of this plant against different genus and species of mosquitoes. [ABSTRACT FROM AUTHOR]

Recent studies have emphasized the application of nanoscience and nanotechnology to disease prevention, diagnosis, and treatment. This study examined the use of marine actinobacteria in the synthesis of silver nanoparticles (AgNPs). UV–Vis spectrophotometry, Fourier infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy were used to characterize the primary structure, crystalline nature, functional groups, shape, and elemental signal of the synthesized AgNPs. The mean particle diameter of the AgNPs was measured, and the size was found to be between 23 and 27 nm. The antibacterial activity of the AgNPs was evaluated; it showed enhanced inhibitory activity against Escherichia coli, Bacillus subtilis, and Klebsiella pneumoniae. At an AgNP concentration of 40 g/mL, the test pathogen growth was completely inhibited. The larvicidal property of the synthesized AgNPs showed enhanced activity against An. stephensi (LC5017.511 and LC9050.572), A. aegypti (LC50 22.481 and LC90 61.920), and Cx. quinquefasciatus (LC50 29.548 and LC90 73.123). By analyzing the phenotypic data, the 16S rRNA gene sequence, and the phylogenetic data, the probable isolate was also determined to be Streptomyces parvisporogenes KL3. The study results prove that biosynthesized AgNPs can be used as effective antibacterial and larvicidal agents in drug formulation. [ABSTRACT FROM AUTHOR]

The field of bio-fabricated noble metallic nanoparticles (NPs) has gained significant attention in applied research due to their eco-friendly and biocompatible nature. This study focuses on employing a green synthesis method to produce silver and gold nanoparticles (bio-fabricated) using a Mangrove plant extract and assessing their insecticidal and growth-inhibitory effects for environmentally friendly pest control. The resulting NPs underwent comprehensive characterization through various spectroscopy techniques. The morphology of both silver and gold mediated nanoparticles of Avicennia marina leaf extract displayed a spherical shape, with average sizes measuring around 70-80 nm and 95-100 nm, respectively. Regarding cytotoxicity, the inhibitory effects of silver nanoparticles were less than that observed by the extract alone while gold nanoparticles showed stronger cell growth inhibitory effects on splenic cells. The hepatic toxicity of silver and gold nanoparticles showed significant toxic effects as compared to A. marina extract alone. Notably, as prepared silver nanoparticles exhibited substantial larvicidal toxicity as compared to gold nanoparticles, when tested against fourth instar Culex pipiens larvae. These biocompatible silver and gold nanoparticles prepared from A. marina leaf extract hold promise for future applications as larvicides to effectively control mosquito species. [ABSTRACT FROM AUTHOR]

A new chitosan derivative bearing a new thiadiazole compound was developed, and its antifungal and larvicidal activities were investigated. The chitosan derivative (coded here as PTDz-Cs) was synthesized by the reaction between the carboxylic derivative of the thiadiazole moiety and chitosan. Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (1H/13C-NMR), gas chromatography–mass spectrometry (GC–MS), elemental analysis, X-Ray diffraction (XRD), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy (XPS) were used to characterize the developed derivatives. Compared to chitosan, the PTDz-Cs derivative has a less crystalline structure and less thermal stability. The antifungal results revealed that PTDz-Cs exhibited potential activity against Rhizopus microspores, Mucor racemosus, Lichtheimia corymbifera, and Syncephalastrum racemosum where inhibition zones were 17.76, 20.1, 38.2, and 18.3 mm, respectively. The larvicidal efficacy of the PTDz-Cs derivative against A. stephensi larvae was tested, and the results exposed that the LC50 and LC90 values (first instar) were 5.432 and 10.398 ppm, respectively, indicating the high susceptibility of early instar mosquito larvae to PTDz-Cs. These results emphasize that this study provided a new chitosan derivative that could be potentially used in the biomedical fields. [ABSTRACT FROM AUTHOR]

The grindstone process, which uses tyrosinase as a catalyst, was used to create analogues of geranylacetone. Tyrosinase was used to prepare the Mannich base under favourable reaction conditions, resulting in a high yield. All synthesized compounds were characterized using FTIR, Nuclear magnetic resonance, and mass spectral analyses. The active geranylacetone derivatives (1a-l) were investigated for larvicidal activity against Culex quinquefasciatus; compound 1b (LD5�€�:20.7 pg/mL) was noticeably more effective than geranylacetone (LD50: >100 ^g/mL) and permethrin (LD50: 24.4 pg/mL) lead compounds because of their ability to kill larvae and use them as pesticides. All compounds (1a-1l) were found to be low toxic, whereas compounds 1b, 1d, and 1k were screened for antifeedant screening of non -aquatic target for the toxicity measurement against marine fish Oreochromis mossambicus at 100 pg/mL caused 0% mortality in within 24 h. Molecular docking studies of synthesised compound 1b and permethrin docked with 3OGN, compound 1b demonstrated a greater binding affinity (-9.6 kcal/mol) compared to permethrin (-10.5 kcal/mol). According to these results, the newly synthesised geranylacetone derivatives can serve as lead molecules of larvicides agents. [ABSTRACT FROM AUTHOR]

Mosquitoes pose a significant threat to public health by transmitting various diseases worldwide. In South-East Asian countries like India, the vector-borne diseases have become a pressing issue. Aedes aegypti and Culex quinquefasciatus are prominent mosquito species responsible for spreading viral infections like dengue and West Nile virus. Traditional vector control methods involving synthetic insecticides present environmental and health hazards, prompting the search for eco-friendly alternatives. This study focuses on Pergularia daemia, a plant with known medicinal properties, as a potential source of bioactive compounds for mosquito control. Crude extracts from P. daemia leaves were prepared using different solvents, and phytochemical screening revealed the presence of alkaloids, steroids, tannins, saponins, flavonoids, and phenolic compounds. Ethanol extracts exhibited the highest larvicidal activity against Ae. aegypti and Cx. quinquefasciatus larvae, with mortality rates proportional to concentration. The results suggest that P. daemia extracts, particularly those in ethanol, hold promise as effective and environmentally friendly mosquito larvicides. [ABSTRACT FROM AUTHOR]

In order to develop natural alternatives to control mosquitoes of medical importance, the chemical composition and insecticidal activity of the essential oil of the rhizomes of Curcuma aeruginosa Roxb were evaluated. The oil was characterized by its organoleptic, physicalchemical properties and ultraviolet and infrared spectra. The quantification of the oil components was carried out by gas chromatography and the major ones were identified by mass spectrometry; Curzerenone was the most abundant component. The insecticidal activity was evaluated in populations of Aedes aegypti, Aedes albopictus and Culex quinquefasciatus using methodologies standardized by the World Health Organization. The oil maintained an homogeneous response against the three mosquito populations, showing significant larvicidal and adulticidal activities. It constitutes the first report of the chemical composition of the essential oil of C. aeruginosa cultivated in the eastern Cuban region and the bioassays conducted demonstrated its insecticidal potential as an ecological alternative. [ABSTRACT FROM AUTHOR]

The present study focuses on the evaluation of the DNA and BSA binding capability, anti‐fungal, metal chelation, and larvicidal activity of extracts of Azadirachta indica A Juss flower. The different extracts of A. indica was prepared by soxhlet extraction using Petroleum Ether (PE), acetone (AC), and hydroalcohol (HA) as solvents. DNA and BSA binding ability of HA extract was calculated through the UV–Visible titrimetric method. The phytochemicals present in the extract show good binding ability towards DNA and BSA. H2O2 and NO scavenging activity were evaluated and HA extracts shows good antioxidant activity with IC50 values of 62 and 48 μg/mg, respectively. The metal chelating property was calculated, where HA shows good chelating ability with the IC50 value of 32.23 μg/mg. The antifungal activity of these extracts was evaluated against different fungal stains; among them, hydroalcoholic extract shows a higher zone of inhibition in all the fungal stains than Petroleum Ether and acetone extracts and acetone extracts (i.e., 50 μg/μL MIC). The potential extract (i.e., HA extract) was used to estimate the larvicidal activity of parasites. The % of mortality was evaluated through a dose‐dependent assay and it is confirmed that when concentration increases, the mortality rate increases. The correlation between metal chelating activity and total flavonoid and phenolic content was calculated and it was found that there is a good correlation (R2 –.743 and.902, respectively). These results proved that HA extract possesses biologically important phytochemicals that contribute to pharmaceutical and biological activities and could be a natural remedy for various real‐time applications. [ABSTRACT FROM AUTHOR]

This study evaluated the chemical composition of essential oil and aqueous leachate from seeds of the invasive neophyte Heracleum mantegazzianum and tested their larvicidal activity against the invasive mosquito Aedes japonicus. Octyl acetate (58.65 %), followed by hexyl 2- methylbutyrate (10.61 %) and hexyl butyrate (9.37 %) dominated the essential oil. Therefore, the larvicidal activity of octyl acetate was tested as well. The 3-hydroxybenzoic acid, syringic acid, and chlorogenic acid were dominant polyphenols in the aqueous leachate. The LC50 and LC90 values of essential oil were 0.067 mg/mL (0.050-0.088) and 0.179 mg/mL (0.135-0.239), those of octyl acetate were as follows: LC50 0.052 mg/mL (0.041-0.065), LC90 0.103 mg/mL (0.082-0.130). The larvicidal effect of the aqueous leachate was expressively lower; values of LC50 and LC90 were 9.235 mg/mL (7.144-11.94) and 32.88 mg/mL (25.44-42.50) respectively. Essential oil, octyl acetate, and aqueous leachate caused some mortality in non-target organisms, too; however, they were significantly lower than those of Asian bush mosquito larvae. [ABSTRACT FROM AUTHOR]

Controlling the vector by eradicating mosquito larvae is frequently done by spreading Abate powder containing 1% Temephos as a larvicide agent. However, the use of Abate powder will possibly increase pesticide residue contamination in the water. This study aimed to explore the potential use of ethanolic extract from red dragon fruit skin to kill mosquito larvae. An experimental laboratory study was performed to examine the larvicidal activity of ethanolic extract from red dragon fruit skin. Maceration method was used to extract active compounds from the fruit skin. Subsequently, the viscous extract was formulated using the wet granulation method to obtain powder form. The larvicide test was done by comparing the lethal concentration (LC50) of mosquito larvae after treatment using the extract and the reference larvicide agent, 1% Temephos Abate. The treatment groups consisted of four different extract concentrations of 1%, 2%, 3%, and 4%. The LC50 of each treatment groups was then calculated against the negative control group. Phytochemical screening showed that the ethanol extract of red dragon fruit skin contains alkaloids, flavonoids, saponins, triterpenoids, and tannins. The larvicide test on Aedes aegypti mosquito larvae showed that the extract treatment hardly killed the Aedes aegypti mosquito larvae. However, on Culex mosquito larvae, the ethanolic extract of red dragon fruit skin was able to kill mosquito larvae, with LC50 value of of 19.06%. The ethanolic extract of red dragon fruit skin was effective on killing the Culex mosquito larvae but not the Aedes aegypti mosquito larvae. [ABSTRACT FROM AUTHOR]

This research investigates the larvicidal efficacy and phytochemical composition of sweet orange (Citrus sinensis) peel methanol extract against Anopheles mosquito larvae collected from temporary rain pool and grassy ditches from Nagazi, Adavi Local Government Area of Kogi State Nigeria. Using appropriate standard methods. Test concentration of 0.5%, 1%, 1.5% and 2% of methanol extract were prepared and tested for its larvicidal efficacy against Anopheles mosquito larva. Larval mortality where recorded after 24, 36, 48 and 72 hours of exposure in three replicates and the mean mortalities were recorded. Lethal concentration value (LC50 and LC90) of the extracts were determined using Probit regression analysis. Phytochemical screening revealed the presence of phenol (281.67 ± 0.23), flavonoid (34.22 ± 0.00), saponin (26.36 ± 0.03), tannins (22.35 ± 0.02), cardiac glycoside (1.66 ± 0.01) and alkaloid (1.06 ± 0.08). The median (LC50) and upper (LC90) lethal concentration of methanol extract of Citrus sinensis peel were 2.49%, 1.48%, 1.09%, 0.88% and 4.25%, 2.58%, 1.91%, 1.69% at 24, 36, 48 and 72 hours respectively. The findings from this research suggests that the methanol extract of Citrus sinensis peel possesses some bioactive components that have the ability to cause lethal effect on the larvae of Anopheles mosquito and can be incorporated into a control strategy in the management of the mosquitoes. [ABSTRACT FROM AUTHOR]

Culex mosquitoes, as nuisance insects and primary vectors of disease, present an important risk to animal and human health. The aim of the present study was to evaluate the larvicidal potential of various extracts (ethanolic, hydro-ethanolic, and essential oil) of Syzygium aromaticum (clove) against the larvae of Culex pipiens. Ethanolic and hydro-ethanolic extracts from Syzygium aromaticum were prepared by ultrasonication, and their composition was determined by phytochemical screening. Gas chromatography-mass spectroscopy (GC-MS) was performed to characterize the Syzygium aromaticum essential oil, which was produced through hydrodistillation. The extracts were tested for their larvicidal activity against Culex pipiens larvae and the LC50 and LC90 values were determined. The results of the phytochemical screening of the ethanolic and hydroethanolic extracts indicated the presence of flavonoids, sterols, terpenes, coumarins, glycosides, and gall tannins. The chemical composition analysis also revealed that eugenol (78.82%) and caryophyllene (16.51%) were the main compounds present in the essential oil. The LC50 and LC90 values obtained for the hydro-ethanolic extract were 557.90 and 939.71 ppm, respectively, while values of 400.14 and 743.32 ppm, respectively, were recorded for the ethanolic extract. The lethal LC50 and LC90 values of the Syzygium aromaticum essential oil demonstrated effectiveness at 1.220 and 5.260 ppm, respectively. Results of this study showed that extracts of Syzygium aromaticum have larvicidal activity against Culex pipiens and could be explored in the development of novel and sustainable mosquito control strategies. [ABSTRACT FROM AUTHOR]

Abstract This paper deals with the evaluation of novel imidazole molecules for their antimicrobial and larvicidal activities. A series of imidazole derivatives 1(a–f) and 2(a–e) were prepared by the Mannich base technique using a Cu(II) catalyst. The Cu(phen)Cl2 catalyst was found to be more effective than other methods. FTIR, elemental analyses, mass spectrometry, 1H NMR, and 13C NMR spectroscopy were performed to elucidate the structures of the synthesised compounds. Antimicrobial and larvicidal activities were investigated for all compounds. The antibacterial activity of compounds (2d) and (2a) were highly active in S.aureus (MIC: 0.25 μg/mL) and K.pneumoniae (MIC: 0.25 μg/mL) compared to ciprofloxacin. Compound (1c) was significantly more effective than clotrimazole in C.albicans (MIC: 0.25 μg/mL). Molecular docking studies of compound 2d showed a higher binding affinity for the 1BDD protein (− 3.4 kcal/mol) than ciprofloxacin (− 4.4 kcal/mol). Compound 1c had a higher binding affinity (− 6.0 kcal/mol) than clotrimazole (− 3.1 kcal/mol) with greater frontier molecular orbital energy and reactivity properties of compound 1c (∆E gap = 0.13 eV). The activity of compound 1a (LD50: 34.9 μg/mL) was more effective in the Culex quinquefasciatus than permethrin (LD50: 35.4 μg/mL) and its molecular docking binding affinity for 3OGN protein (− 6.1 kcal/mol). These newly synthesised compounds can act as lead molecules for the development of larvicides and antibiotic agents.

Dengue is an endemic disease with a high incidence in almost all Southeast Asian countries, including Indonesia. This infectious disease is caused by a virus transmitted by the bite of Aedes aegypti mosquito as the main vector. Effective mosquito vector control is a crucial step in stopping the spread of this virus. Of the several methods available, the use of larvicides is considered one of the most successful treatments in reducing the number of mosquito vectors. However, widely used synthetic larvicides can have undesirable side effects on the environment and non-target organisms including human health. The aim of this study was to discover a new biolarvicide from natural materials that is relatively safer. In this study, the biolarvicidal activity of mangrove plant species that are commonly found in Ngurah Rai Mangrove Forest Bali was tested, namely Sonneratia alba. Mangrove root simplicia was extracted by reflux method using three different solvents namely methanol, chloroform, and n-hexane. The content of compounds in the extract were analyzed using GC/MS method. The larvicidal activity of the extracts were tested on A. aegypti instar III/IV larvae with concentrations of 0.1, 1, 10, 100, and 1000 ppm for 24 hours. Subsequently, the average value of larval mortality was used to calculate the LC50 of each extract. The results showed that S. alba methanol extract provided the best larvicidal activity compared to chloroform and n-hexane extracts, with mortality of 69.33% at a concentration of 1000 ppm and LC50 of 1265 ppm. GC-MS analysis showed that the methanol extract of S. alba contained five dominant compounds namely Methyl 2-hydroxy-eicosanoate (19.55%); 4H-1-Benzopyran-4-one, 3,5-dihydroxy-2-(4-hydroxy-3-methoxyphenyl)-7-methoxy (16.48%); 4-((1E)-3-Hydroxy-1-propenyl)-2-methoxyphenol (10.06%); Benzamide, N-[4-(2-naphtyl)-2-thiazolyl]- (9.40%); and 2,3-Dihydro-3,5-bis(3-methoxyphenyl)-1H-inden-1-one (6.52%). The results of this study provide a preliminary result on larvicide activity from mangrove S. alba in order to develop bio larvicides from nature which is safer for human health and environment.

The aim of the current study is to assess the toxicity of Austroplenckia populnea leaf extracts towards the Spodoptera frugiperda population in laboratory conditions. Initially, a crude methanolic extract was obtained from dried leaves of A. populnea . This extract was fractionated using hexane, ethyl acetate, and then methanol. Neonate S. frugiperda larvae were isolated in plastic containers and fed (once) on corn leaf fragments treated with crude and fractions of the investigated plant extracts. The life cycle of the larvae treated with the extracts was monitored. In addition to the intake of leaves treated with the plant extracts, such variables as larval and pupal mortality rate, larval and pupal weight, and larval, pupal, and adult stage duration were evaluated. The crude, hexane, and methanol extract fractions exerted an antixenosis effect on the feeding behaviour of neonate S. frugiperda larvae. A significant antibiosis effect was observed for the hexane fraction of the A. populnea extract, since all of its concentrations promoted a S. frugiperda larval mortality rate differing from that observed for the control. The pupal mortality rate was low, but it did not differ significantly from the mortality rate observed for the control treatment, which was nil. The larvicidal effect of the A. populnea leaf extract, mainly of its hexane fraction, has indicated its potential to be used in integrated S. frugiperda management programs.

This research investigates the larvicidal efficacy and phytochemical composition of sweet orange (Citrus sinensis) peel methanol extract against Anopheles mosquito larvae collected from temporary rain pool and grassy ditches from Nagazi, Adavi Local Government Area of Kogi State Nigeria. Using appropriate standard methods. Test concentration of 0.5%, 1%, 1.5% and 2% of methanol extract were prepared and tested for its larvicidal efficacy against Anopheles mosquito larva. Larval mortality where recorded after 24, 36, 48 and 72 hours of exposure in three replicates and the mean mortalities were recorded. Lethal concentration value (LC50 and LC90) of the extracts were determined using Probit regression analysis. Phytochemical screening revealed the presence of phenol (281.67 ± 0.23), flavonoid (34.22 ± 0.00), saponin (26.36 ± 0.03), tannins (22.35 ± 0.02), cardiac glycoside (1.66 ± 0.01) and alkaloid (1.06 ± 0.08). The median (LC50) and upper (LC90) lethal concentration of methanol extract of Citrus sinensis peel were 2.49%, 1.48%, 1.09%, 0.88% and 4.25%, 2.58%, 1.91%, 1.69% at 24, 36, 48 and 72 hours respectively. The findings from this research suggests that the methanol extract of Citrus sinensis peel possesses some bioactive components that have the ability to cause lethal effect on the larvae of Anopheles mosquito and can be incorporated into a control strategy in the management of the mosquitoes.

The grindstone process, which uses tyrosinase as a catalyst, was used to create analogues of geranylacetone. Tyrosinase was used to prepare the Mannich base under favourable reaction conditions, resulting in a high yield. All synthesized compounds were characterized using FTIR, Nuclear magnetic resonance, and mass spectral analyses. The active geranylacetone derivatives (1a-l) were investigated for larvicidal activity against Culex quinquefasciatus; compound 1b (LD50:20.7 μg/mL) was noticeably more effective than geranylacetone (LD50: >100 μg/mL) and permethrin (LD50: 24.4 μg/mL) lead compounds because of their ability to kill larvae and use them as pesticides. All compounds (1a-1l) were found to be low toxic, whereas compounds 1b, 1d, and 1k were screened for antifeedant screening of non -aquatic target for the toxicity measurement against marine fish Oreochromis mossambicus at 100 μg/mL caused 0% mortality in within 24 h. Molecular docking studies of synthesised compound 1b and permethrin docked with 3OGN, compound 1b demonstrated a greater binding affinity (−9.6 kcal/mol) compared to permethrin (−10.5 kcal/mol). According to these results, the newly synthesised geranylacetone derivatives can serve as lead molecules of larvicides agents.

Antimicrobial resistance and cancer claim millions of lives each year, making it important to find effective medications. The current study focuses on the rapid and sustainable manufacture of nickel oxide nanoparticles using Sargassum wightii aqueous extract (SW-NiO NPs) as a novel antibacterial and anticancer agent. The presence of phytochemicals in the Sargassumwightii in all extract was qualitatively screened and water extract, which is found to contain abundant phytochemical was used for the biosynthesis. Thus synthsized SW-NiO nanoparticles was characterised by UV–Visible, FT-IR, XRD, SEM, and TEM spectral studies, and then screend for its invitro anti microbial activity against bacterial strains (E. coli, K. pneumoniae, S. aureus, and B. subtilis) and fungal activity with the fungus strains (C. albicans, C. tropicalis),invitro anticancer and larvicidal activity. The SW-NiO NPs possessed cubic and hexagonal structures with an average crytallite size of 15–20 nm, according to the results of the analytical characterization. SEM and TEM analysis confirms the spherical like morphology and their respective elemental composition were identified by EDAX studies. The antimicrobial activity was carried by well diffusion method.Compared to gram-negative organisms, gram-positive species were more vulnerable to the SW-NiO NPs with the zone of inhibition 17 mm. The fungal activity results showed the zone of inhibition 16 and 14 mm. It was also found that SW-NiO NPs inhibit the growth of tested fungus at higher doses. The cytotoxicity studies with liver cancer cell line through MTT assay revealed the inhibition value at 52.25 ± 0.05 µM, indicating their sensitivity to the HepG2 cell line. SW-NiO NPs made with water extract showed the highest larvicidal activity and 88.33 % death of Aedes agypti(AE). The LC50 and LC90 values for SW-NiO NPs against Aedes agypti(AE) larvae are found to be 31.420 and 134.261 ppm, respectively. The findings of the antimicrobial, larvicidal and invitro anticancer screening of this work provide compelling evidence that SW-NiO NPs made from an aqueous extract of Sargassum wightii have considerable biological applications which can be explored in detail on identifying the potential phyto constituents which are responsible for the activity.

Insecticidal activities of synthesized silver nanoparticles of leaf extract of Datura metel L. (Solanaceae) (DM) against grubs Epilachna vigintioctopunctata F. (Coleoptera, Coccinellidae) at varying levels of concentrations was evaluated. DM leaf extract was used to create AgNPs, and nanoparticle production could be seen after six hours. UV-vis spectrophotometer, Particle size analyzer, FTIR and SEM analysis were used to confirm the synthesis of AgNPs. GCMS spectra of leaf extract of DM showed 20 substances, of which nine were known s phytochemicals and the others were unidentified. UV-visible spectra to analyse the Surface Plasmon Resonance for AgNPs revealed in the range of 366 - 374nm. LC50 values for the AgNPs synthesized leaf extracts calculated 24 h after treatment against the fourth instar larvae of E. vigintioctopunctata using probit analysis revealed the LC50 of the aqueous leaf extract as 252.31ppm and that of AgNPs synthesized leaf extract as 396.09ppm. When comparing the aqueous and AgNPs synthesized leaf extracts, AgNPs nanoparticles synthesized leaf extracts were more efficient as larvicide than aqueous leaf extract. [ABSTRACT FROM AUTHOR]

Globally, several million peoples are infected with epidemic-prone mosquito-borne diseases like yellow fever and malaria that is transmitted to humans by the bites of infected mosquitoes. Psoralea corylifolia, often known as babchi, is a well-liked herb that has been utilised in traditional Ayurvedic and Chinese medicine for many years for its miraculous abilities to treat a variety of skin conditions and Leptadenia reticulata, also known as Jivanti is an herb that is traditionally used in treating the conditions like malaria, diabetes, and liver disorders. The present study investigated the larvicidal properties of endophytic fungi isolated from Psoralea corylifolia and Leptadenia reticulata against Aedes aegypti. The highest larvicidal activity was seen in Trichodermata viride and Candida albicans species from leaves of L. reticulata was found to be 85.71% and 90.47 at 20 ppm. Likewise, Piriformospora indica and Aspergillus niger species from the leaves of P. corylifolia was found to be 66.66% and 83.33 % respectively. Candida albicans from leaves of L. reticulata and Aspergillus niger from the leaves of Psoralea corylifolia showed the highest mortality percentage was found to be 90.47 and 83.33 at 20 ppm respectively. The present study reveals the determination of optimal, eco-friendly, and selective mosquito larvicidal agents. The development of innovative and affordable medications to combat diseases spread by mosquitoes will be aided by more research on the isolation, characterisation, and determination of the mechanism of action against the selective mosquitos. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sphodroxia maroccana Ley is a pest of cork oak crops that damages the roots of seedlings and can severely impair cork oak regeneration. Since the banning of carbosulfan and chlorpyriphos, which were widely used against the larvae of Sphodroxia maroccana because of their harmful impact on the environment, until now there has been no pesticide against these pests. Therefore, it is particularly urgent to develop highly effective insecticidal molecules with novel scaffolds. Isoxazolines are a class of insecticides that act on γ‐aminobutyric acid (GABA)‐gated chloride channel allosteric modulators. In this work, a green synthesis of novel 3,5‐disubstituted isoxazoline‐sulfonamide derivatives was achieved in water via ultrasound‐assisted four‐component reactions, and their insecticidal activities against fourth‐instar larvae of S. maroccana were evaluated. RESULTS: Most of the tested compounds showed insecticidal activity compared to fluralaner as positive control and commercially available insecticide. Especially, the isoxazoline‐secondary sulfonamides containing halogens (Br and Cl) on the phenyl group attached to the isoxazoline, 6g (LC50 = 0.31 mg/mL), 6j (LC50 = 0.38 mg/mL), 6k (LC50 = 0.18 mg/mL), 6L (LC50 = 0.49 mg/mL), 6m (LC50 = 0.24 mg/mL), 6q (LC50 = 0.46 mg/mL), exhibited much higher larvicidal activity than fluralaner (LC50 = 0.99 mg/mL). CONCLUSION: Novel isoxazolines containing sulfonamide moieties were designed, synthesized and confirmed by two single‐crystal structures of 4e and 6q. Their bioassay results showed significant larvicidal activity with significant morphological changes in vivo. These results will lay the foundation for the further discovery and development of isoxazoline‐sulfonamide derivatives as novel crop protection larvicides of cork oak. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This paper deals with the evaluation of novel imidazole molecules for their antimicrobial and larvicidal activities. A series of imidazole derivatives 1(a–f) and 2(a–e) were prepared by the Mannich base technique using a Cu(II) catalyst. The Cu(phen)Cl2 catalyst was found to be more effective than other methods. FTIR, elemental analyses, mass spectrometry, 1H NMR, and 13C NMR spectroscopy were performed to elucidate the structures of the synthesised compounds. Antimicrobial and larvicidal activities were investigated for all compounds. The antibacterial activity of compounds (2d) and (2a) were highly active in S.aureus (MIC: 0.25 μg/mL) and K.pneumoniae (MIC: 0.25 μg/mL) compared to ciprofloxacin. Compound (1c) was significantly more effective than clotrimazole in C.albicans (MIC: 0.25 μg/mL). Molecular docking studies of compound 2d showed a higher binding affinity for the 1BDD protein (− 3.4 kcal/mol) than ciprofloxacin (− 4.4 kcal/mol). Compound 1c had a higher binding affinity (− 6.0 kcal/mol) than clotrimazole (− 3.1 kcal/mol) with greater frontier molecular orbital energy and reactivity properties of compound 1c (∆E gap = 0.13 eV). The activity of compound 1a (LD50: 34.9 μg/mL) was more effective in the Culex quinquefasciatus than permethrin (LD50: 35.4 μg/mL) and its molecular docking binding affinity for 3OGN protein (− 6.1 kcal/mol). These newly synthesised compounds can act as lead molecules for the development of larvicides and antibiotic agents. [ABSTRACT FROM AUTHOR]

The use of herbal medicines and phytonutrients is quickly spreading around the world due to their effectiveness and lack of adverse effects. Plants are being used different treatments in folk medicine. Evaluation of the antibacterial, in vitro anti-diabetic, and larvicidal properties of L. Mentha arvensis, Allium sativum, and Zingiber officinale plants was the study's main goal. The plant materials were extracted with ethyl acetate and ethanol to give respective extracts to identify the area where some bacterial strains are inhibited by extracts. The agar well diffusion technique was used to assess the extracts antibacterial activity. Both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria were tested against it. Zones of inhibition of extracts were compared with control standards like ampicillin. Mosquitoes have always been a human health threat. In order to create a natural mosquito larvicide that is safe for the environment, the death rates were estimated after the plant extracts were tested for larvicidal action against the larvae of the Aedes aegypti mosquito vector both separately and in combination. Diabetes mellitus is a chronic illness, and the management of diabetes is a global problem. When compared to the existing synthetic pharmaceuticals to treat such chronic illnesses and disorders, herbal remedies have less side effects. Antidiabetic activity was studied by inhibition of α-amylase enzyme using spectrophotometer. The plants in the study were found to have α-amylase inhibiting activity. [ABSTRACT FROM AUTHOR]

The present study evaluates the potentiality of green silver nanoparticles from the leaves and fruit extracts of Phyllanthus acidus L. against third instar larvae of two vector mosquitoes namely Culex quinquefasciatus and Culex vishnui. Various spectroscopic techniques were used to characterize the synthesized silver nanoparticles (AgNPs). Synthesized silver nanoparticles from both the leaf and fruits of P. acidus were spherical to quasi-spherical in shape and showed Surface Plasmon Resonance (SPR) bands at 420 and 409 nm respectively. In larvicidal bioassay with synthesized AgNPs from the leave of P. acidus, 100% mortality was observed at 20 ppm against third instar larvae of both the mosquito species with LC50 values of 1.64 and 0.87 ppm respectively. 100% mortality was observed in 5 ppm concentration against both Cx. quinquefasciatus and Cx. vishnui in synthesized AgNPs from fruits of P. acidus with LC50 values of 1.62 and 1.24 ppm respectively. The above findings suggest that the AgNPs synthesized from P. acidus leaves and fruit extracts have the potential to be employed in vector mosquito population control. [ABSTRACT FROM AUTHOR]

This study aimed to explore the antibacterial and larvicidal potential of actinobacterial strains isolated from soil samples of Pakistan. Out of fourteen purified actinobacteria, antibiotic susceptibility profile confirmed five isolates showing resistance against tested antibiotics (ampicillin; lincomycin; rifampicin and erythromycin). Ribotyping confirmed that these isolates belong to Streptomyces species and were identified as S. monticola, S. septentrionalis, S. polaris, S. desertarenae and S. lutosisoli. Primary screening of the five isolates using cross streak method showed excellent zone of inhibition (ZI 10-27 mm) against tested pathogens (Escherichia coli, Klebsiella pneumoniae, Bacillus licheniformis, Pseudomonas aeruginosa and Bacillus subtilis). Secondary screening using ethyl acetate extracts also showed significant ZI in the range of 06 - 14.0 mm (P ≤ 0.05) against these pathogens thus confirming their bioactive potential. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of screened Actinomycetes was in the range of 1.3 - 3.5 mgmL-1 and 1.9 - 4.0 mgmL-1 of bacterial biomass, respectively. Three isolates, S. monticola, S. septentrionalis and S. polaris showed 100 % mortality at 1000 ppm against Anopheles 3rd instar larvae. These findings indicated that actinobacterial isolates possess antibacterial and larvicidal potential. Further extraction and purification of bioactive components from these bacterial may be a good source of novel antibiotics and natural-insecticides. [ABSTRACT FROM AUTHOR]

[Objective] The objective of this study was to determine the larvicidal activity against A. aegypti of ethanolic extracts of plants commonly found in Costa Rica. [Methodology] Larvicidal activity of ethanolic extracts of plants was determined in this study using the WHO/VBC/81.807: WHO/VBC/81. from 1981. An analysis PROBID for dose response was conducted to determine LC50 of the most prominent extracts. [Results] A total of six extracts with the highest toxicity were chosen, with the stem extract of Ipomoea cairica having the lowest LC50 of 0.0341 mg/mL, followed by I. cairica leaf extract with an LC50 of 0.121 mg/mL. The larvicidal activity of ethanolic extracts of plants was determined in this study, with an emphasis on the larvicidal potential of I. cairica as an environmentally friendly alternative for the control of A. aegypti. [Conclusions] The larvicidal activity for ethanolic extracts of different plants, with an emphasis on the larvicidal potential of I. cairica as an environmentally friendly alternative for the control of A. aegypti.

Aedes aegypti mosquito is responsible for the transmission of some of the most serious vector-borne diseases affecting humans, including dengue fever, chikungunya, and Zika. The only effective method for minimizing their transmission is vector control. In this work, an environmentally friendly method for synthesizing cerium oxide nanoparticles (CeO2 NPs) is highlighted, and the larvicidal activity against Ae. aegypti was studied. This method uses the aqueous extract of Bruguiera cylindrica leaves (BL) as an oxidizer and stabilizing agent. UV–Vis spectroscopy presented a distinctive absorbance band at 303 nm for CeO2 NPs with a band gap of 3.17 eV. The functional groups from the plant extract connected to CeO2 NPs were identified by FT-IR analysis, while X-ray diffraction revealed the cubic fluorite orientation of CeO2 NPs. Zeta potential revealed a surface charge of −20.7 mV on NPs. The formation of CeO2 NPs was confirmed by an energy dispersive spectral analysis, and TEM and DLS revealed an average diameter of 40–60 nm. The LC50 of synthesized CeO2 against Ae. aegypti fourth instar larvae was reported to be 46.28 μg/mL in 24 h. Acetylcholinesterase (47%) and glutathione S-transferase (13.51%) activity were significantly decreased in Ae. aegypti larvae exposed to synthesized CeO2 NPs versus the control larvae. All these findings propose the potential for using B. cylindrica leaves-synthesized CeO2 NPs as an efficient substitute for insecticides in the management of mosquitoes.

The overuse of synthetic insecticides has led to various negative consequences, including insecticide resistance, environmental pollution, and harm to public health. This may be ameliorated by using insecticides derived from botanical sources. The primary objective of this study was to evaluate the anti-mosquito activity of the essential oil (EO) of Citrus reticulata Blanco cv. Chachiensis (Chachi) (referred to as CRB) at immature, semi-mature, and mature stages. The chemical compositions of the CRB EO were analyzed using GC-MS. The main components were identified to be D-limonene and γ-terpinene. The contents of D-limonene at the immature, semi-mature, and mature stages were 62.35%, 76.72%, and 73.15%, respectively; the corresponding contents of γ-terpinene were 14.26%, 11.04%, and 11.27%, respectively. In addition, the corresponding contents of a characteristic component, methyl 2-aminobenzoate, were 4.95%, 1.93%, and 2.15%, respectively. CRB EO exhibited significant larvicidal activity against Aedes albopictus (Ae. albopictus, Diptera: Culicidae), with the 50% lethal doses being 65.32, 61.47, and 65.91 mg/L for immature, semi-mature, and mature CRB EO, respectively. CRB EO was able to inhibit acetylcholinesterase and three detoxification enzymes, significantly reduce the diversity of internal microbiota in mosquitoes, and decrease the relative abundance of core species within the microbiota. The present results may provide novel insights into the utilization of plant-derived essential oils in anti-mosquitoes.

Plant extracts and essential oils can be alternative environmentally friendly agents to combat pathogenic microbes and malaria vectors. Myrrh is an aromatic oligum resin that is extracted from the stem of Commiphora spp. It is used in medicine as an insecticide, cytotoxic, and aromatic. The current study assessed the effect of Commiphora myrrha resin extracts on the biological potency of the third larval stage of Aedes aegypti, as well as its antioxidant and cytotoxic properties against two types of tumor cells (HepG-2 and Hela cell lines). It also used GC–MS to determine the chemical composition of the C. myrrha resin extracts. Fifty components from the extracted plant were tentatively identified using the GC–MS method, with curzerene (33.57%) typically listed as the primary ingredient, but other compounds also make up a significant portion of the mixture, including 1-Methoxy-3,4,5,7-tetramethylnaphthalene (15.50%), β-Elemene (5.80%), 2-Methoxyfuranodiene (5.42%), 2-Isopropyl-4,7-Dimethyl-1-Naphthol (4.71%), and germacrene B (4.35%). The resin extracts obtained from C. myrrha exhibited significant efficacy in DPPH antioxidant activity, as evidenced by an IC50 value of 26.86 mg/L and a radical scavenging activity percentage of 75.06%. The 50% methanol extract derived from C. myrrha resins exhibited heightened potential for anticancer activity. It demonstrated substantial cytotoxicity against HepG-2 and Hela cells, with IC50 values of 39.73 and 29.41 µg mL−1, respectively. Notably, the extract showed non-cytotoxic activity against WI-38 normal cells, with an IC50 value exceeding 100 µg mL−1. Moreover, the selectivity index for HepG-2 cancer cells (2.52) was lower compared to Hela cancer cells (3.40). Additionally, MeOH resin extracts were more efficient against the different growth stages of the mosquito A. aegypti, with lower LC50, LC90, and LC95 values of 251.83, 923.76, and 1293.35 mg/L, respectively. In comparison to untreated groups (1454 eggs/10 females), the average daily number of eggs deposited (424 eggs/L) decreases at higher doses (1000 mg/L). Finally, we advise continued study into the possible use of C. myrrha resins against additional pests that have medical and veterinary value, and novel chemicals from this extract should be isolated and purified for use in medicines.