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As a result of its high reactivity, furan-2(3H)-one derivative 2 can be selected as a versatile and suitable candidate for building of novel nitrogen heterocyclic compounds. Consequently, furan-2(3H)-one derivative 2 and some nitrogen nucleophiles were utilized as starting materials for the formation of new pyridazinone and pyrrolone derivatives bearing naphthalene moiety. The continuous buildup of insecticide resistance is the main obstacle facing pest control measures. Pyrrole-based insecticides are a favourable choice due to their unique mode of action and no cross-resistance with traditional neurotoxic insecticides. The larvicidal activities of pyrrolone derivatives were assessed against field and laboratory strains of Culex pipiens larvae in comparison with chlorfenapyr (pyrrole insecticide). Compounds 17 (21.05 µg/mL) > 9 (22.81 µg/mL) > 15 (24.39 µg/mL) > 10 (26.76 µg/mL) > 16 (32.09 µg/mL) were most effective against lab strain of C. pipiens larvae relative to chlorfenapyr (25.43 µg/mL). While in field strain, 17 and 15 were the most toxic compounds followed by 9 > 10 > 16 > 2 with LC50 of 9.87, 10.76, 11.52, 12.68, 15.32 and 18.37 µg/mL, respectively, compared with chlorfenapyr with 14.03 µg/mL. The cytochrome P-450 monooxygenase activities were significantly increased in treated larvae of lab and field strains relative to untreated. The great variations in toxicity of the synthesized compounds were interpreted by structure-activity relationship study. The pyrrolone derivatives are effective against field and insecticide-resistant strains. Therefore, they are considered promising compounds to be integrated into pest management programs. [ABSTRACT FROM AUTHOR]

This study investigated chemical compositions and biocidal activities from the aerial parts of Rhododendron thymifolium against Tribolium castaneum, Lasioderma serricorne, and Ditylenchus destructor. In total, 13 components were isolated from the aerial parts of R. thymifolium by chromatographic separation techniques. Based on the results of MS, 1H NMR, and 13C NMR spectrometry, their structures were determined as ent-kaurane-16β-ol (1), pentacosane (2), undecanoic acid, ethyl ester (3), 1-Tridecanethiol (4), 1-Dodecanol (5), 4-Methyl-7-hydroxycoumarin (6), tertradecan-1-ol (7), apocynin (8), 3-Methoxy-4-methylbenzaldehyde (9), scopoletin (10), hyperin (11), quercetin (12), acetophenone (13). In addition, ent-kaurane-16β-ol (1) was isolated from R. thymifolium for the first time. Then, the insecticidal toxicities against T. castaneum, L. serricorne, and D. destructor. of compounds 1–13 were evaluated, and the results showed that apocynin (8) and acetophenone (13) exhibited obvious contact activity against the storage pests with LD50 values of 6.46 and 8.72 μg/adult respectively. Acetophenone (13) showed excellent contact activity against D. destructor with LC50 values of 0.08 mg/mL. The study clearly showed the active fractions from R. thymifolium have might potential to be developed into potential compounds on storage insect prevention. [ABSTRACT FROM AUTHOR]

The search for natural product-based biopesticides from endophytic fungi is an effective tool to find new solutions. In this study, we studied a pre-selected fungal endophyte, isolate YCC4, from the paleoendemism Persea indica, along with compounds present in the extract and the identification of the insect antifeedant and nematicidal ones. The endophyte YCC4 was identified as Phyllosticta sp. by molecular analysis. The insect antifeedant activity was tested by choice bioassays against Spodoptera littoralis, Myzus persicae, and Rhopalosiphum padi, and the in vitro and in vivo mortality was tested against the root-knot nematode Meloidogyne javanica. Since the extract was an effective insect antifeedant, a strong nematicidal, and lacked phytotoxicity on tomato plants, a comprehensive chemical study was carried out. Two new metabolites, metguignardic acid (4) and (-)-epi-guignardone I (14), were identified along the known dioxolanones guignardic acid (1), ethyl guignardate (3), guignardianones A (5), C (2), D (7), and E (6), phenguignardic acid methyl ester (8), the meroterpenes guignardone A (9) and B (10), guignarenone B (11) and C (12), (-)-guignardone I (13), and phyllomeroterpenoid B (15). Among these compounds, 1 and 4 were effective antifeedants against S. littoralis and M. persicae, while 2 was only active on the aphid M. persicae. The nematicidal compounds were 4, 7, and 8. This is the first report on the insect antifeedant or nematicidal effects of these dioxolanone-type compounds. Since the insect antifeedant and nematicidal activity of the Phyllosticta sp. extract depend on the presence of dioxolanone components, future fermentation optimizations are needed to promote the biosynthesis of these compounds instead of meroterpenes. [ABSTRACT FROM AUTHOR]

Fusing insect derived neurotoxic peptides with Galanthus nivalis agglutinin (GNA) has been shown to enhance the insecticidal activity of the neuropeptides, especially when administered orally. This study produced a recombinant scorpion insect specific neurotoxin BjαIT, GNA, and a fusion protein BjαIT/GNA using Pichia pastoris as an expression host. Recombinant rBjαIT/GNA was found to be easily degraded during expression in yeast which and produced a main protein product with a molecular weight of approximately 14 kDa. Cytotoxicity results showed that rBjαIT, rGNA, and rBjαIT/GNA had no toxicity to mammalian NIH/3T3 cells. Adding rBjαIT or rBjαIT/GNA at a concentration as low as 1 ng/mL to insect cell culture medium inhibited the proliferation of insect Sf9 cells, with rBjαIT exhibiting stronger cytotoxicity, while 20 ng/mL rGNA did not inhibit the proliferation of Sf9 cells. Silkworm larval injection results showed that rBjαIT/GNA was the most toxic of the three proteins, followed by rBjαIT, and rGNA. When rBjαIT/GNA was injected at a concentration of 0.129 nmol/g body weight 46.7% of silkworm died within 48 h. Feeding newly hatched silkworms with rBjαIT/GNA at a leaf surface concentration of 40 µg/cm2 resulted in 76.7% mortality within 24 h. However, rBjαIT/GNA showed almost no oral insecticidal activity against second instar silkworms. The results indicated that rBjαIT/GNA has stronger injection insecticidal activity and feeding insecticidal activity than rBjαIT and rGNA individually, making it more suitable for biological control. [ABSTRACT FROM AUTHOR]

Insecticidal potential of extracts of Citrus aurantifolia, family Rutaceae, was evaluated to control whiteflies, Bemisia tabaci. Biocidal activity directed chromatographic separation of chloroform and butanol fractions, with spectral identification (1D-NMR, 2D-NMR, ESIMS) of the active fractions have been resulted in separation and structural elucidation of for previously described coumarins (bergapten 1, limettin 2, isopimpinellin 3, oxypeucedanin hydrate 4) in addition to a new dimeric coumarin (12R, 12'R)-aurantifolin 5, two known limonoids; 21,23-dihydro-23-methoxy-21-oxolimonin 6, 21,23-dihydro-23-methoxy-21-oxonomilin 7, and two known flavonoid glycosides; scoparin 8, and narcissin 9. Amongst these compounds, narcissin 9 was the most effective after 24 h. of treatment while, (12R, 12'R)-aurantifolin 5 was the most potent against B. tabaci, 3rd instar nymphs after 72 h. of treatment and under laboratory conditions, with LC50 values of 33.31and 15.92 ppm, respectively comparing with the positive control azadirachtin. [ABSTRACT FROM AUTHOR]

A preliminary in silico screening of 94 compounds, including colchicine, caffeine, gramine, and their derivatives, was conducted to identify potential herbicides, insecticides, and fungicides. Among the compounds tested, only gramine and its 13 derivatives exhibited potential activity. These compounds were further tested against eight species of insects, three species of weeds, and four species of fungi. All of the tested alkaloids were found to be ineffective as herbicides and insecticides, but they did exhibit some fungicidal activity. Four gramine derivatives showed some activity against Phytophthora infestans, Botrytis cinerea, Zymoseptoria tritici, and Fusarium culmorum. [ABSTRACT FROM AUTHOR]

Purpose: Agricultural losses caused by pests have a profound impact on African and Asian countries. In this context, the whitefly Bemisia tabaci is an important global pest and attacks many vegetables. However, conventional pesticides cause unwanted effects on the environment and consumers, in addition to the development of resistance. Therefore, sustainable resources have been used and researched, including those of natural origin. Research Method: The objective of this review was to compile and discuss studies of essential oils found in Asian and African countries with action against B. tabaci. For this, scientific studies on active essential oils were searched in databases such as Scopus, Web of Science, Google Scholar, and Science Direct. Findings: The work explored essential oils from 48 different species belonging to 19 families. Notably, the families Asteraceae, Lamiaceae, Lauraceae, Myrtaceae, and Poaceae presented the highest number of studies. Among the evaluated oils, Allium sativum oil demonstrated potent fumigant insecticidal action. Similarly, essential oils from Cinnamomum camphora, Thymbra spicata, Rosmarinus officinalis, and Laurus nobilis exhibited high activity against pests. Promising essential oils with high potency against pests also include Mentha pulegium, Mentha viridis, and Syzygium aromaticum. Research Limitations: Despite the diversity of active essential oils against B. tabaci, further studies on the development and stability of formulations must be carried out. Originality/value: This review highlighted the abundance of active essential oils in Africa and Asia as natural resources for sustainable pest management in the B. tabaci control. [ABSTRACT FROM AUTHOR]

This review delves into the multifaceted biological activity of isoxazole, a versatile heterocyclic compound that has garnered significant attention in the realm of medicinal chemistry. Isoxazole derivatives have exhibited a wide array of pharmacological properties, ranging from antimicrobial and anti‐inflammatory activities to anticancer and neuroprotective effects. This comprehensive examination aims to provide a detailed overview of the molecular mechanisms underlying the biological actions of isoxazole, exploring its potential as a promising scaffold for drug development. The review encompasses recent advancements, structure‐activity relationships, and key findings from both in vitro and in vivo studies, offering insights into the therapeutic potential of isoxazole in various disease contexts. By synthesizing the current state of knowledge, this article aims to serve as a valuable resource for researchers and practitioners interested in the medicinal significance of isoxazole and its derivatives. [ABSTRACT FROM AUTHOR]

Natural products received much attention as an environmentally beneficial solution for pest management. Therefore, the extracts of invasive silverleaf nightshade (Solanum elaeagnifolium Cav.) weeds using their berries parts (seeds, peels and mucilage) supported by bioassay-guided fractionation were tested against both the greater wax moth (Galleria mellonella) and Erwinia carotovora pv. carotovora causes of the blackleg of potatoes. The seeds and peels of S. elaeagnifolium were successively extracted by maceration using dichloromethane (DCM), ethyl acetate (EtOAc), and ethanol (EtOH), respectively. While, its mucilage was extracted using EtOAc. The successive EtOH extract of the plant seeds had promising inhibition efficacy and the best minimal inhibition concentration (MIC) of 50 µg/ml against E. Carotovora amongst other extracts (DCM and EtOAc of the plant berries parts). Depending on dose response activity, EtOH extract had G. mellonella larval mortality and pupal duration rates (LC50; 198.30 and LC95; 1294.73 µg/ml), respectively. Additionally, this EtOH extract of seeds was fractionated using preparative TLC to three characteristic bands. The insecticidal and bacterial activities of these isolated bands (SEA, SEB, and SEC) were evaluated at a dose of 100 µg/ml, causing mortality by 48.48, 62.63 and 92.93% (G. mellonella larvae) and inhibition by 15.22, 0.00 and 31.66 mm (E. carotovora), respectively. Moreover, the separated major three bands were tentatively identified using LC-ESI-MS analysis revealing the presence of two phenolic acids; chlorogenic acid (SEA) and dicaffeoyl quinic acid (SEB) in addition to one steroidal saponin (SEC) annotated as borassoside E or yamoscin. Finally, the plant seeds' successive EtOH extract as well as its active constituents, exhibited potential broad-spectrum activity and the ability to participate in future pest management initiatives. A field study is also recommended to validate its bio-efficacy against selected pests and to develop its formulations. [ABSTRACT FROM AUTHOR]

The Lamiaceae family is widely distributed worldwide. In this study, we investigated the insecticidal activity of five Lamiaceae essential oils against Thrips flavus Schrank and the phytotoxic activity against Glycine max (L.) Merr., Zea mays L., Portulaca oleracea L., and Echinochloa oryzoides (Ard.) Fritsch. Then, the chemical composition of the five essential oils was analyzed by using gas chromatography–mass spectrometry (GC-MS). The five Lamiaceae essential oils were melissa, basil, rosemary, negundo chastetree, and salvia. The main constituents of the five Lamiaceae essential oils were preliminarily determined to be as follows: α-pinene and 1,8-cineole in the rosemary essential oil; β-pinene, γ-terpinene, and d-limonene in the negundo chastetree essential oil; β-cadinene and isolongifolen-5-one in the melissa essential oil; 5-allylguaiacol in the basil essential oil; and isopropyl myristate, linalyl acetate, and linalool in the salvia essential oil. Using a bioassay, it was found that, among the five essential oils, the melissa essential oil exhibited the lowest LC50 value, which was 0.18 mg/mL, and the salvia essential oil exhibited the highest LC50 value, which was 0.42 mg/mL. The control efficacy of the five essential oils significantly increased with time and concentration in pot experiments. The negundo chastetree, basil, rosemary, and salvia essential oils at 900.00 g a.i.·hm−2 showed high control efficacy against T. flavus, with values higher than 90%. Female thrips were attracted to the negundo chastetree essential oil. The five essential oils were also tested for their effects on the germination rate, germination potential, germination index, and shoot length of G. max, Z. mays, P. oleracea, and E. oryzoides. The basil essential oil significantly inhibited the germination of P. oleracea, with germination at a concentration of 1.0 mg/mL being only 11.11 ± 5.09%. This study provides a reference for the development of botanical pesticides to control T. flavus, crops, and weeds. [ABSTRACT FROM AUTHOR]

Modern lifestyles have increased the focus on food stability and human health due to evolving industrial goals and scientific advancements. Pathogenic microorganisms significantly challenge food quality, with Salmonella enterica and other planktonic cells capable of forming biofilms that make them more resistant to broad-spectrum antibiotics. This research examined the chemical composition and antibacterial and antibiofilm properties of the essential oil from Eugenia caryophyllus (ECEO) derived from dried fruits. GC-MS analyses identified eugenol as the dominant component at 82.7%. Additionally, the study aimed to extend the shelf life of sous vide deer meat by applying a plant essential oil and inoculating it with S. enterica for seven days at 4 °C. The essential oil demonstrated strong antibacterial activity against S. enterica. The ECEO showed significant antibiofilm activity, as indicated by the MBIC crystal violet test results. Data from MALDI-TOF MS analysis revealed that the ECEO altered the protein profiles of bacteria on glass and stainless-steel surfaces. Furthermore, the ECEO was found to have a beneficial antibacterial effect on S. enterica. In vacuum-packed sous vide red deer meat samples, the anti-Salmonella activity of the ECEO was slightly higher than that of the control samples. These findings underscore the potential of the ECEO's antibacterial and antibiofilm properties in food preservation and extending the shelf life of meat. [ABSTRACT FROM AUTHOR]

Varroa destructor is a dangerous pest directly for beekeeping and indirectly for crops that require insect pollination. In recent years, the application of chemical pesticides has led to the occurrence of mite resistance and contamination of hive products. Plant extracts are considered as a suitable alternative to chemical acaricides for the Varroa mite control. Therefore, the present study aimed to investigate the acaricidal and insecticidal activity of extract of Prangos ferulacea plant against the Varroa mite and its host in the honey bee colonies in the climatic conditions of Kurdistan province from 2022 to 2024. The P. ferulacea plant was collected in June 2022 from different regions of Kurdistan province in the flowering stage, extracted and then its chemical compounds were identified using GC-MS. The present study was conducted in the form of a factorial experiment based on a completely random basic design with four treatments and seven replications. Before conducting the bioassay experiments, the experimental colonies were homogenized in terms of queen age, population (adults and brood), and honey storage. Also, the initial infestation rate of colonies with Varroa mites was evaluated for adult and brood. The results showed that the extract of 50% of P. ferulacea was relatively favorable acaricidal properties. So that, there was no significant difference with oxalic acid and Apistan treatments in terms of mite mortality percentage in the first time of spraying. Also, the result showed that the bee's mortality percentage was not more than 7% in any of the times of spraying with the 50% extract of the P. ferulacea, and there was observed a significant difference compared to the oxalic acid and Apistan treatments in terms of bee's mortality percentage (P<0.01). The queen superseding was not observed in any of the experimental treatments. According to the findings of the present research, the concentration of 50% of the extract P. ferulaceous can be suggested as a suitable alternative to synthetic acaricides and organic acids to control the Varroa mite in honey bee colonies. [ABSTRACT FROM AUTHOR]

The key objective of this study was to determine the chemical composition, insecticidal and butyrylcholinesterase (BChE) inhibitory activities of crude essential oils (CEO) extracted from the stem-leaf parts of the endemic Centaurea paphlagonica plant via steam distillation, as well as its chromatography-based fractions for the first time. According to GC-MS analysis, eighty-five compounds were identified representing 98.49% of the total essential oil. β-Eudesmol (15.17%), phytol (8.69%), and spathulenol (8.03%) were determined as the main components. The CEO demonstrated a remarkably insecticidal activity against S. granarius and R. dominica insects, ranging from 98.35% to 100%, while achieving a 50% against T. confusum at a 10% concentration. The silica gel-based fractionation of CEO resulted in four qualitatively different fractions (CEO-F1 to F4). The CEO-F2, predominantly comprised of β-eudesmol and spathulenol, exhibited superior activity compared to CEO across all tested insects. In addition, the inhibitory activity of BChE, which causes death in insects by altering nervous system activities, was assessed. BChE inhibition activity of CEO and CEO-F2 was determined as IC50=346.57 μg/mL and 96.02 μg/mL, respectively, supporting the insecticidal activity tests and molecular docking studies. The volatile oil obtained from C. paphlagonica can be considered a potential natural source to combat storage product pests, with its significant natural volatile compounds. [ABSTRACT FROM AUTHOR]

In the search for natural and non-toxic products alternatives to synthetic pesticides, the fumigant and repellent activities of 35 essential oils are predicted in the human head louse (Pediculus humanus capitis) through the Quantitative Structure-Activity Relationships (QSAR) theory. The number of constituents of essential oils with weight percentage composition greater than 1% varies from 1 to 15, encompassing up to 213 structurally diverse compounds in the entire dataset. The 27,976 structural descriptors used to characterizing these complex mixtures are calculated as linear combinations of non-conformational descriptors for the components. This approach is considered simple enough to evaluate the effects that changes in the composition of each component could have on the studied bioactivities. The best linear regression models found, obtained through the Replacement Method variable subset selection method, are applied to predict 13 essential oils from a previous study with unknown property data. The results show that the simple methodology applied here could be useful for predicting properties of interest in complex mixtures such as essential oils. [ABSTRACT FROM AUTHOR]

Tenvermectin B is a patented novel macrocyclic lactone insecticide independently developed in China. In order to develop its potential market and delay the emergence of resistance, the insecticidal activities of tenvermectin B to 10 pest varieties, such as Plutella xylostella, Pyrausta nubilalis, and Hyphantria cunea, were performed by leaf dipping method. The activities against Aphis gossypii, Tetranychus urticae, and Liriomyza sativae were conducted by spraying method. Sun Yunpei's cotoxicity (CTC) method was used to evaluate the synergistic effect of the mixtures of tenvermectin with thioacetamide, chlorfenapyr, and indoxacarb on P. xylostella, and the optimal ratio was employed for field efficacy assay. The bioassay showed that tenvermectin B had higher control activity against P. xylostella, P. nubilalis and T. urticae, compared with abamectin, the LC50 values were 0.115, 0.043, and 0.012 mg/L, respectively. Tenvermectin B also displayed high activity against Mythimna separata, H. cunea, Cnaphalocrocis medinalis, Frankliniella occidentalis and A. gossypii, the LC50 values ranged from 0.337-9.784 mg/L. Mixture screening showed that tenvermectin B with neither thiotraniliprole nor indoxacarb had synergistic effect on P. xylostella. The mixture of tenvermectin B and chlorfenapyr showed significant synergy against P. xylostella, with a CTC value of 178.59 at the optimal ratio of tenvermectin B to chlorfenapyr as 1 : 14 (m : m). The result of the field trial indicated that at 7 d and 14 d after treatment, the control efficacies of the mixture against P. xylostella were over 80% at the dosage of 75 g a.i./hm². Our study demonstrated that tenvermectin B had a broad insecticidal spectrum, with excellent activity against P. xylostella, T. urticae, A. gossypii, etc., showing promising potential for development and application. The mixture of tenvermectin B and chlorfenapyr (1 : 14) showed a synergistic effect and could be further developed for P. xylostella control to delay the emergence of resistance. [ABSTRACT FROM AUTHOR]

This study focuses on six Eucalyptus species, namely E. badjensis, E. benthamii, E. dunnii, E. grandis, E. globulus, and E. saligna aiming at a sustainable use of their green biomass. These species were grown at the same location and stage of development. Leaf essential oils were extracted by hydrodistillation using a Clevenger apparatus during the four seasons. Gas chromatography–mass spectrometry (GC–MS) and high-performance thin-layer chromatography (HPTLC) techniques were used to analyze the chemical composition. E. badjensis consistently exhibited a dominant composition, with 1,8-cineole being the predominant component. Notably, the proportion of 1,8-cineole in E. badjensis was 77.35% in spring (SP), 69.46% in summer (SU), 95.30% in autumn (AU), and 89.30% in winter (WI). E. globulus also exhibited 1,8-cineole as its primary constituent, with proportions fluctuating slightly across seasons at 84.87%, 79.94%, 81%, and 85.88%, respectively. The proportions and constituents of various species differed significantly. HPTLC was successfully used as a swift technique to monitor the chemical composition of essential oils (EOs) in various Eucalyptus species during the seasonality. GC–MS and HPTLC analysis showed that different Eucalyptus species displayed unique chemical compositions, while both the chemical profile and productivity of all analyzed EOs were affected by seasonality. This finding was demonstrated in the principal components cluster. The analysis of six species has revealed that the EO of E. benthamii is the most potent in thwarting the infestation of Cimex lectularius. Additionally, all six EOs demonstrated antioxidant activity in the ABTS model. EOs of E. benthamii, E. dunnii, and E. grandis showed significant anti-inflammatory activities in experimental models.Highlights: E. badjensis, E. dunnii, and E. globulus are promising sources for the commercial exploitation of 1,8-cineole E. benthamii, E. grandis, and E. dunni presented anti-inflammatory activity The essential oils of six species showed antioxidant activity. E. benthamii EO presented a potent insecticide against Cimex lectularius adults. Eucalyptus leaf biomass as a novel resource for the pharmaceutical, nutraceutical, and insecticidal industries [ABSTRACT FROM AUTHOR]

Abstract As a result of its high reactivity, furan-2(3H)-one derivative 2 can be selected as a versatile and suitable candidate for building of novel nitrogen heterocyclic compounds. Consequently, furan-2(3H)-one derivative 2 and some nitrogen nucleophiles were utilized as starting materials for the formation of new pyridazinone and pyrrolone derivatives bearing naphthalene moiety. The continuous buildup of insecticide resistance is the main obstacle facing pest control measures. Pyrrole-based insecticides are a favourable choice due to their unique mode of action and no cross-resistance with traditional neurotoxic insecticides. The larvicidal activities of pyrrolone derivatives were assessed against field and laboratory strains of Culex pipiens larvae in comparison with chlorfenapyr (pyrrole insecticide). Compounds 17 (21.05 µg/mL) > 9 (22.81 µg/mL) > 15 (24.39 µg/mL) > 10 (26.76 µg/mL) > 16 (32.09 µg/mL) were most effective against lab strain of C. pipiens larvae relative to chlorfenapyr (25.43 µg/mL). While in field strain, 17 and 15 were the most toxic compounds followed by 9 > 10 > 16 > 2 with LC50 of 9.87, 10.76, 11.52, 12.68, 15.32 and 18.37 µg/mL, respectively, compared with chlorfenapyr with 14.03 µg/mL. The cytochrome P-450 monooxygenase activities were significantly increased in treated larvae of lab and field strains relative to untreated. The great variations in toxicity of the synthesized compounds were interpreted by structure-activity relationship study. The pyrrolone derivatives are effective against field and insecticide-resistant strains. Therefore, they are considered promising compounds to be integrated into pest management programs.

Abstract Insecticidal potential of extracts of Citrus aurantifolia, family Rutaceae, was evaluated to control whiteflies, Bemisia tabaci. Biocidal activity directed chromatographic separation of chloroform and butanol fractions, with spectral identification (1D-NMR, 2D-NMR, ESIMS) of the active fractions have been resulted in separation and structural elucidation of for previously described coumarins (bergapten 1, limettin 2, isopimpinellin 3, oxypeucedanin hydrate 4) in addition to a new dimeric coumarin (12R, 12’R)-aurantifolin 5, two known limonoids; 21,23-dihydro-23-methoxy-21-oxolimonin 6, 21,23-dihydro-23-methoxy-21-oxonomilin 7, and two known flavonoid glycosides; scoparin 8, and narcissin 9. Amongst these compounds, narcissin 9 was the most effective after 24 h. of treatment while, (12R, 12’R)-aurantifolin 5 was the most potent against B. tabaci, 3rd instar nymphs after 72 h. of treatment and under laboratory conditions, with LC50 values of 33.31and 15.92 ppm, respectively comparing with the positive control azadirachtin.

Plant extracts are considered as a suitable alternative to chemical acaricides for the Varroa mite control. Therefore, the present study aimed to investigate the acaricidal and insecticidal activity of extract of Prangos ferulacea plant against Varroa mite and its host in the honey bee colonies in the climatic conditions of Kurdistan province from 2022 to 2024. The P. ferulacea plant was collected in June 2022 from different regions of Kurdistan province in the flowering stage, extracted and then its chemical compounds were identified using GC-MS. The present study was conducted in the form of a factorial experiment based on a completely random basic design with four treatments and seven replications. Before conducting the bioassay experiments, the experimental colonies were homogenized in terms of queen age, population (adults and brood), and honey storage. Also, the initial infestation rate of colonies with Varroa mites was evaluated for adult and brood. The results showed that the extract of 50% of P. ferulacea was relatively favorable acaricidal properties. So that, there was no significant difference with oxalic acid and Apistan treatments in terms of mite mortality percentage in the first time of spraying. Also, the result showed that the bee’s mortality percentage was not more than 7% in any of the times of spraying with the 50% extract of the P. ferulacea, and there was observed a significant difference compared to the oxalic acid and Apistan treatments in terms of bee’s mortality percentage (P

Abstract Natural products received much attention as an environmentally beneficial solution for pest management. Therefore, the extracts of invasive silverleaf nightshade (Solanum elaeagnifolium Cav.) weeds using their berries parts (seeds, peels and mucilage) supported by bioassay-guided fractionation were tested against both the greater wax moth (Galleria mellonella) and Erwinia carotovora pv. carotovora causes of the blackleg of potatoes. The seeds and peels of S. elaeagnifolium were successively extracted by maceration using dichloromethane (DCM), ethyl acetate (EtOAc), and ethanol (EtOH), respectively. While, its mucilage was extracted using EtOAc. The successive EtOH extract of the plant seeds had promising inhibition efficacy and the best minimal inhibition concentration (MIC) of 50 µg/ml against E. Carotovora amongst other extracts (DCM and EtOAc of the plant berries parts). Depending on dose response activity, EtOH extract had G. mellonella larval mortality and pupal duration rates (LC50; 198.30 and LC95; 1294.73 µg/ml), respectively. Additionally, this EtOH extract of seeds was fractionated using preparative TLC to three characteristic bands. The insecticidal and bacterial activities of these isolated bands (SEA, SEB, and SEC) were evaluated at a dose of 100 µg/ml, causing mortality by 48.48, 62.63 and 92.93% (G. mellonella larvae) and inhibition by 15.22, 0.00 and 31.66 mm (E. carotovora), respectively. Moreover, the separated major three bands were tentatively identified using LC-ESI-MS analysis revealing the presence of two phenolic acids; chlorogenic acid (SEA) and dicaffeoyl quinic acid (SEB) in addition to one steroidal saponin (SEC) annotated as borassoside E or yamoscin. Finally, the plant seeds’ successive EtOH extract as well as its active constituents, exhibited potential broad-spectrum activity and the ability to participate in future pest management initiatives. A field study is also recommended to validate its bio-efficacy against selected pests and to develop its formulations.

The purpose of the current study is to assess the chemical profile, antioxidant, antimicrobial, and insecticide efficacy of essential oil derived from the leaf of Moroccan Mentha aquatica L. (MA-EO) using in vitro and in silico analysis. Using GC-MS/MS analysis, 18 components of MA-EO were identified, including linalool (42.42%), α-elemol (10.45%), α-terpineol (8.07%), linalyl acetate (7.37%), and caryophyllene (4.05%). Additionally, MA-EO has a strong antioxidant capacity with IC50 values of 0.64 ± 0.01 µg/mL using the DPPH assay and 0.167 ± 0.13 µg/mL using the ABTS test. Total antioxidant capacity activities were found to be 188.21 ± 0.31 mg EAA/g, while RP activities were 1.95 ± 0.023. The powerful antibacterial properties of MA-EO were proven to be effective against Escherichia coli and Candida albicans. MA-EO showed insecticidal potential using the fumigation experiment, with an LC50 of 3.33 μL/L in the air after 24 h of exposure. At a dose of 20 µL/mL, MA-EO reduced fertility, fecundity, and emergence of adult C. maculatus. MA-EO had 95% mortality at the same dosage. In silico analysis revealed that the antioxidant activity of MA-EO is linked to γ-eudesmol, while its antibacterial efficacy is associated with phenol, 2,4-di-tert-butyl-, and its antifungal capacity with phenol, 2,4-di-tert-butyl-. MA-EO demonstrates potent bactericidal, fungicidal, and bioinsecticide properties, making it effective for controlling bacteria, fungi, and insect pests in stored grains.

The objective of this investigation was to assess the chemical makeup of essential oil derived from Ptychotis verticillata (PVEO), and to examine its antifungal, insecticidal, and repellent properties. PVEO was extracted through hydrodistillation, and its volatile constituents were analyzed using Headspace Solid-Phase Microextraction Gas Chromatography-Mass Spectrometry. Qualitative and quantitative evaluation of antifungal activity was carried out using the agar diffusion method and the minimum inhibitory concentration (MIC) test against Candida glabrata, Saccharomyces cerevisiae, Aspergillus niger and Penicillium digitatum. We evaluated the repellent potential, as well as the contact and inhalation toxicity of PVEO against Callosobruchus maculatus. The results of the study indicated that the essential oil of P. verticillata was composed mainly of γ-Terpinen (25.86%), β-Cymene (18.70%) O-Cymen-5-ol (16.78) and α-Pinene (12.13%). PVEO showed potent antifungal activity against all strains tested. The results of insecticidal activity of this essential oil were promising in adult C. maculatus. At a dose of 20 ml · dm–3 of air, EO caused maximum mortality with an LC50 value of 5.64 ml · dm–3 for the inhalation test and 3.4 ml · dm–3 for the contact test. In addition, a significant decrease in the number of eggs laid and adult emergence was observed as EO doses increased, reaching a reduction of around 95% at a dose of 20 ml · dm–3 of air. In terms of repellent activity, PVEO also showed encouraging results. It demonstrated an average repellent activity of around 92 ± 10.95%. Furthermore, molecular docking simulations corroborated the in vitro results and demonstrated that specific p-Menthen-3-one compounds formed more robust hydrogen bonding interactions with the target receptors. These experiments underscore PVEO’s effectiveness as a fungicide against the tested fungal strains, demonstrating its role as a bio-insecticide against C. maculatus adults, and its potential as an appealing repellent. This suggests that PVEO could serve as a valuable alternative within integrated pest management strategies.

To discover novel and efficient compounds against Aphis gossypii Glover, a series of novel terpene ester derivatives containing the structure of bicyclo[2.2.1]heptane were designed and synthesized using tschimganin as the lead compound. Bioactivity assays showed that most tschimganin analogs exhibited moderate to outstanding insecticidal activity against A. gossypii. In particular, compound 56 (LC50 = 0.28 μg mL−1), identified as (1S,2S,4R)-1,7,7-trimethylbicyclo[2.2.1]heptan-2-yl nicotinate, exhibited the best activity, which was significantly superior to that of imidacloprid (LC50 = 0.54 μg mL−1) and sulfoxaflor (LC50 = 0.70 μg mL−1). The precise and dependable 3D-QSAR model suggests a promising direction for further design of more active tschimganin-based insecticides. Metabolomics showed that compound 56 disrupted detoxification, amino acid biosynthesis, and energy metabolism and may affect the central nervous system of A. gossypii. The results of this study indicated that tschimganin analogs are a potential new class of green insecticides that can be used for the integrated management of A. gossypii.

The gambir plant can serve as a raw material for botanical insecticides. Plant-based insecticides are made in nanoemulsion form to overcome the insecticide particle size problem. This study aims to obtain a gambir waste form that has the potential to be used as a botanical insecticide using nanotechnology. The laboratory experiments include preliminary and follow-up tests. The preliminary test involves testing each extract (liquid, solid, and raw gambir waste) at three concentrations using a completely randomized design with four replications. The follow-up test uses the residue method on leaves to test insecticidal activity. Creating nanoemulsion from gambir waste involves mixing organic and liquid phases through spontaneous emulsification. The insecticidal effectiveness of this nanoemulsion is tested on Croccidolomia pavonana. The results show that solid and liquid gambir waste has the potential to be used as alternative insecticides, which can influence the mortality of C. pavonana with an LC50 concentration of 0.22 (solid waste) and 0. 29 (liquid waste), while LC95 is 2.44 (solid waste) and 2.52 (liquid waste). The research promotes utilizing natural resources and innovative technologies, advancing environmentally conscious pest control methods, and fostering sustainable agricultural systems.

Callosobruchus maculatus (Fabricius), also known as the cowpea beetle or pulse beetle, is the most important pest of stored cowpea. The beetle causes both qualitative and quantitative losses in the grains, all of which result in low crop yields. The objective of this work was to investigate the insecticidal effect of rose essential oil (REO) on adult Callosobruchus maculatus in terms of mortality and oviposition. In addition, the viable mesophilic aerobic bacteria of C. maculatus were evaluated, and surface molecular electrostatic potential (MEP) maps were examined to determine the interaction domains of the bioactive components of REO. The interaction mechanism between the AChE enzyme (PDB ID: 6XXY, 4EY6, 4EY7 and 6O4W) and the REO components was investigated using the molecular docking method. The highest mortality of 92.40 ± 0.03% was obtained at 16 μL within 72 h of exposure. Higher concentrations of the essential oil decreased the laying performance of C. maculatus. A significant decrease of 91.33% in the number of eggs laid was observed. Gas chromatography–mass spectrometry (GC/MS) results showed that the major constituents of Rosa damascena Miller essential oil (REO) were citronellol (46.15%), geraniol (16.19%), nonadecane (8.80%) and nerol (7.43%). Treatments of 4, 8, 12 and 16 μL of REO significantly reduced the viable mesophilic aerobic bacteria of C. maculatus samples compared with the control. It was found that the most effective binding was between the REO components and the 4EY7 protein, with binding energies ranging from −6.9 to −8.9 kcal/mol. Although the major component of REO was citronellol (46.15%), the best interaction was observed with farnesol isomer B (0.80%). Overall, these results suggest that REO has the potential to control C. maculatus as an environmentally friendly alternative to synthetic pesticides. [ABSTRACT FROM AUTHOR]

Diaphorina citri Kuwayama (D. citri) is one of the major pests in the citrus industry, which spreads Citrus Huanglongbing disease. It has developed resistance to chemical insecticides. Therefore, searching for greener solutions for pest management is critically important. The main aim of this study was to evaluate the repellent and insecticidal efficacy of essential oils (EOs) from four species of Myrtaceae plants: Psidium guajava (PG), Eucalyptus robusta (ER), Eucalyptus tereticornis (ET), and Baeckea frutescens (BF) against D. citri and to analyze their chemical compositions. GC-MS analysis was performed, and the results indicated that the EOs of PG, ER, ET, and BF were rich in terpenoids, ketones, esters, and alcohol compounds. The repellent rate of all four EOs showed that it decreased with exposure time but increased with the concentration of EOs from 80.50% to 100.00% after treating D. citri for 6 h with four EOs at 100% concentration and decreased to 67.71% to 85.49% after 24 h of exposure. Among the compounds from the EOs tested, eucalyptol had the strongest repellent activity, with a 24 h repellency rate of 100%. The contact toxicity bioassay results showed that all EOs have insecticidal toxicity to D. citri; the LC50 for nymphs was 36.47–93.15 mL/L, and for adults, it was 60.72–111.00 mL/L. These results show that when PG is used as the reference material, the ER, ET, and BF EOs have strong biological activity against D. citri, which provides a scientific basis for the further development of plant-derived agrochemicals. [ABSTRACT FROM AUTHOR]

Anacyclus pyrethrum , a native Algerian medicinal plant, demonstrates notable therapeutic efficacy. The bioactive profile of the Anacyclus pyrethrum extract was examined using HPLC-UV-VIS, which showed a high concentration of phenolic compounds (33.46 ± 0.57 mg EAG/g EP) and flavonoids (11.08 ± 0.24 mg E Qu/g EP). The Anacyclus pyrethrum extract exhibited significant antioxidant activity in iron chelation (IC50 = 0.019 ± 0.0006 mg/ml) DPPH (IC50 = 0.142± 0.001 mg/ml), ABTS+ (IC50 = 0.079 ± 0.0005 mg/ml) and OH (IC50 = 0.845 ± 0.052mg/ml) radicals. Anti-inflammatory investigations were conducted using both in vitro and in silico methods. The in vitro testing involved evaluating the denaturation of egg albumin and BSA, while the in silico tests focused on measuring the effect of caffeic acid on the COX-2 protein. The anti-inflammatory capacity of the substance was similar to that of Aspirin, with a value of 76.1 ± 1.04% compared to Aspirin's 81.11 ± 1.6%. Our extract exhibited a fatal dose (LD50) of 45.847 ± 1.661 mg/ml and showed significant antibacterial activity with minimum inhibitory concentrations (MICs) ranging from 2.5 to 27.5 mg/ml. The findings emphasize the wide range of medicinal uses of Anacyclus pyrethrum, underscoring its significance in both traditional and modern pharmacology. [ABSTRACT FROM AUTHOR]

There is a high interest in utilizing natural bioactive products derived from plants as a substitute for synthetic chemicals in the industry. This research focuses on the phytochemical composition of essential oils (EOs) of Ammi visnaga L. and Trachyspermum ammi L and their insecticidal activity against Sitophilus oryzae (L.), a common pest found in stored cereals. The EOs were extracted through steam distillation and analyzed using gas chromatography coupled with mass spectrometry (GC-MS). The EOs of A. visnaga consisted of twenty-four components, with Abietadiene (41.23%) being the most abundant, followed by linalool (25.54%) and limonene (19.04%). On the other hand, the EOs of T. ammi consisted of twenty-eight main components, with isothymol being the most abundant (51.88%). The results revealed that the EOs of T. Ammi (DL50 = 0.1 µL EOs/L of air) were more toxic than A. visnaga (0.38 µL EOs/L of air), with the toxicity varying based on doses and exposure periods. To further understand the molecular mechanisms underlying this activity, molecular docking and dynamic simulations were performed using the major chemical constituents of the oils. The simulation results indicated that the major compounds, Abietadiene and isothymol, interact with the catalytic sites of the target proteins, inhibiting acetylcholinesterase and chitin synthase. These interactions form energetically favorable systems that remain stable throughout the molecular dynamic period. This research provides valuable insights into the potential of these EOs as natural insecticides and highlights the importance of molecular modeling in understanding the biological activities of plant-derived compounds. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The escalating resistance of agricultural pests to chemical insecticides necessitates the development of novel, efficient, and safe biological insecticides. Conus quercinus, a vermivorous cone snail, yields a crude venom rich in peptides for marine worm predation. This study screened six α-conotoxins with insecticidal potential from a previously constructed transcriptome database of C. quercinus, characterized by two disulfide bonds. These conotoxins were derived via solid-phase peptide synthesis (SPPS) and folded using two-step iodine oxidation for further insecticidal activity validation, such as CCK-8 assay and insect bioassay. The final results confirmed the insecticidal activities of the six α-conotoxins, with Qc1.15 and Qc1.18 exhibiting high insecticidal activity. In addition, structural analysis via homology modeling and functional insights from molecular docking offer a preliminary look into their potential insecticidal mechanisms. In summary, this study provides essential references and foundations for developing novel insecticides. [ABSTRACT FROM AUTHOR]

To develop highly efficient and structurally novel insect growth regulators, 20 1-phenyl-5-amino pyrazoles were designed and synthesized using ecdysteroid receptor (EcR) as the target and I7 (N-(4-cyano-1-phenyl-1H-pyrazol-5-yl)-2-phenylacetamide), a highly active compound discovered by our group, as a lead. All synthesized structures were confirmed by ¹H NMR, 13C NMR and HRMS. The insecticidal activity of the compounds showed that the lethality of compounds M10, M17 and M18 was more than 20% higher than that of lead compound I7 (60%) at a concentration of 250 mg/L. Compound M10 was the most active, exhibiting a lethality rate of 60% at 125 mg/L, which is slightly lower than that of the commercial tebufenozide (70%), and Plutella xylostella treated with this compound showed typical symptoms of ecdysteroid analogue poisoning. The results of the target binding activity of P. xylostella EcR(PxEcR) showed that the compounds M2, M6, M9, M12, M13, M15 and M20 were better than that of compound I7, and that the target binding activity of compound M15 (IC50(PxEcR) = 2.02 μmol/L) was 11.5 times higher than that of compound I7 (IC50(PxEcR) = 23.21 μmol/L). The binding mechanism between compounds I7, M10, M15 and EcR receptor was further analyzed by molecular docking and molecular dynamics simulation, which will provide guidance for the further research on insect growth regulators targeting EcR. [ABSTRACT FROM AUTHOR]

Metarhizium rileyi has a broad biocontrol spectrum but is highly sensitive to abiotic factors. A Colombian isolate M. rileyi Nm017 has shown notorious potential against Helicoverpa zea. However, it has a loss of up to 22 % of its conidial germination after drying, which limits its potential as a biocontrol agent and further commercialization. Conidial desiccation resistance can be enhanced by nutritional supplements, which promotes field adaptability and facilitates technological development as a biopesticide. In this study, the effect of culture medium supplemented with linoleic acid on desiccation tolerance in Nm017 conidia was evaluated. Results showed that using a 2 % linoleic acid-supplemented medium increased the relative germination after drying by 41 % compared to the control treatment, without affecting insecticidal activity on H. zea. Also, the fungus increased the synthesis of trehalose, glucose, and erythritol during drying, independently of linoleic acid use. Ultrastructural analyses of the cell wall-membrane showed a loss of thickness by 22 % and 25 %, in samples obtained from 2 % linoleic acid supplementation and the control, respectively. Regarding its morphological characteristics, conidia inner area from both treatments did not change after drying. However, conidia from the control had a 24 % decrease in length/width ratio, whereas there was no alteration in conidia from acid linoleic. The average value of dry conidia elasticity coefficient from linoleic acid treatment was 200 % above the control. Medium supplementation with linoleic acid is a promising fermentation strategy for obtaining more tolerant conidia without affecting production and biocontrol parameters, compatible solutes synthesis, or modifying its cell configuration. • Linoleic acid increased dry conidia germination without affecting its insecticidal activity. • The addition of linoleic acid did not affect compatible solutes synthesis. • Linoleic acid decreased dry conidia cell wall shrinking and length/width ratio. • The addition of linoleic acid enhanced the elasticity coefficient of dry conidia. [ABSTRACT FROM AUTHOR]

Tribolium castaneum is a significant pest in grain storage, causing considerable economic impact globally. Plant-derived insecticides are being employed as alternatives to chemical insecticides and have shown strong insecticidal activity against T. castaneum. However, the mechanism underlying the insecticidal effects of plant-derived insecticides on T. castaneum remains unclear. In this study, we investigated the repellent, fumigation, and contact activities of R. anthopogonoides essential oil (EO) and its four main chemical components against T. castaneum. The results demonstrated that both the EO and its main chemical component, benzylacetone, exhibited potent insecticidal activity against T. castaneum. Benzylacetone may be the primary active component of R. anthopogonoides EO against T. castaneum. Subsequently, transcriptome sequencing of T. castaneum treated with Benzylacetone, along with negative controls, revealed 1616 differentially expressed genes (DEGs), with 758 up-regulated and 858 down-regulated genes. GO analysis indicated that the DEGs were mainly enriched in "cellular process," "metabolic process," "cell," "cell part," "catalytic activity," "binding," and other categories. KEGG pathway analysis revealed that the 417 DEGs were distributed across 217 different pathways, with several pathways related to xenobiotic or drug metabolism significantly enriched. This suggests that Benzylacetone likely disrupts metabolic and detoxication processes. Additionally, qRT-PCR validation of the TcOBP-4E and TcCYP450-6BK11 genes exhibited consistent results with the transcriptome data. Homology modeling and molecular docking results indicated the presence of a binding cavity formed by numerous hydrophobic amino acid residues in TcOBPs, with possible hydrogen bonds and hydrophobic interaction forces between the protein and ligand. These findings suggest that OBP and CYP450 play crucial roles in the resistance to foreign substances and provide a theoretical basis for understanding the insecticidal mechanisms of plant-derived insecticides at the molecular level. [ABSTRACT FROM AUTHOR]

Cytochrome P450 (CYP450)‐catalyzed oxidative coupling is an efficient strategy for using simple building blocks to construct complex structural scaffolds of natural products. Among them, heterodimeric coupling between two different monomers is relatively scarce, and the corresponding CYP450s are largely undiscovered. In this study, we discovered a fungal CYP450 (CpsD) and its associated cps cluster from 37208 CYP450s of Pfam PF00067 family member database and subsequently identified a group of new skeleton indole piperazine alkaloids (campesines A−G) by combination of genome mining and heterologous synthesis. Importantly, CYP450 CpsD mainly catalyzes intermolecular oxidative heterocoupling of two different indole piperazine monomers to generate an unexpected 6/5/6/6/6/6/5/6 eight‐ring scaffold through the formation of one C−C bond and two C−N bonds, illuminating its first dimerase role in this family of natural products. The proposed catalytic mechanism of CpsD was deeply investigated by diversified substrate derivatization. Moreover, dimeric campesine G shows good insecticidal activity against the global honeybee pest Galleria mellonella. Our study shows a representative example of discovering new skeleton monomeric and dimeric indole piperazine alkaloids from microbial resources, expands our knowledge of bond formation by CYP450s and supports further development of the newly discovered and engineered campesine family compounds as potential biopesticides. [ABSTRACT FROM AUTHOR]

The gambir plant can serve as a raw material for botanical insecticides. Plant-based insecticides are made in nanoemulsion form to overcome the insecticide particle size problem. This study aims to obtain a gambir waste form that has the potential to be used as a botanical insecticide using nanotechnology. The laboratory experiments include preliminary and follow-up tests. The preliminary test involves testing each extract (liquid, solid, and raw gambir waste) at three concentrations using a completely randomized design with four replications. The follow-up test uses the residue method on leaves to test insecticidal activity. Creating nanoemulsion from gambir waste involves mixing organic and liquid phases through spontaneous emulsification. The insecticidal effectiveness of this nanoemulsion is tested on Croccidolomia pavonana. The results show that solid and liquid gambir waste has the potential to be used as alternative insecticides, which can influence the mortality of C. pavonana with an LC50 concentration of 0.22 (solid waste) and 0. 29 (liquid waste), while LC95 is 2.44 (solid waste) and 2.52 (liquid waste). The research promotes utilizing natural resources and innovative technologies, advancing environmentally conscious pest control methods, and fostering sustainable agricultural systems. [ABSTRACT FROM AUTHOR]

Investigations have shown that storage bugs seriously harm grains during storage. In the interim, essential oils (EOs) have been proven to be a good botanical pesticide. The anti-Lasioderma serricorne properties of Elsholtzia ciliata essential oil, which was obtained by steam distillation, were evaluated using DL-limonene, carvone, and their two optical isomer components using contact, repelling, and fumigation techniques. Simultaneously, the fumigation, contact, and repellent activities of carvone and its two optical isomers mixed with DL-limonene against L. serruricorne were evaluated. The results showed that E. ciliata, its main components (R-carvone, DL-limonene), and S-carvone exhibited both fumigations (LC50 = 14.47, 4.42, 20.9 and 3.78 mg/L) and contact (LD50 = 7.31, 4.03, 28.62 and 5.63 µg/adult) activity against L.serricorne. A binary mixture (1:1) of R-carvone and DL-limonene displayed an obvious synergistic effect. A binary mixture (1:1) of carvone and its two optical isomers exhibited an obvious synergistic effect, too. Furthermore, the repellent activity of the EO, carvone, and its two optical isomers, DL-limonene, and a combination of them varied. To stop insect damage during storage, E. ciliata and its components can be utilized as bio-insecticides. [ABSTRACT FROM AUTHOR]

In the present work, novel series of Schiff base 2-7 were synthesized via treatment of p-tosyloxy benzaldehyde with some indole and quinoxaline derivatives in ethanol under reflux. All product structures were verified using elemental analysis and spectroscopic investigations, including 13C NMR, 1H NMR, and IR. Our research was conducted on the insecticidal activity, and biological effects of the recently synthesized Schiff bases on S. frugiperda. The results showed that compound 5 was the most active insecticide, nearly surpassing methomyl as a reference, with LC50 values of 46.35 mg/L for second-instar larvae and 97.37 mg/L for fourth-instar larvae. This research opened up new avenues for the search for a novel class of insecticide. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China Agricultural University is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phosphonate structures in phosphonate compounds are biologically active organic synthetic materials derived from natural products. Due to their unique carbon-phosphorus (C–P) bonds, phosphonate compounds are highly biologically active and less susceptible to resistance and have the advantages of high efficacy, fast efficacy, low dosage, and wide use. With the increasing prevalence of drug resistance of pathogens, there is growing concern regarding the development of new environmentally friendly and non-drug resistant pesticides. In this review, we focused on phosphonate compounds with herbicidal, bactericidal, fungicidal, insecticidal, antiviral, and plant growth regulation functions, providing a basis for the development of new phosphonate compound pesticides. [ABSTRACT FROM AUTHOR]

IntroductionIn malaria management, insecticides play a crucial role in targeting disease vectors. Benzothiazole derivatives have also been reported to possess insecticidal properties, among several other properties they exhibit. The female Anopheles mosquito is responsible for transmitting the malaria parasite when infected. Anopheles gambiae (Ag) and Anopheles funestus (Af) are two of the most notable Anopheles species known to spread malaria in Nigeria. Trehalase is an enzyme that breaks down trehalose. Recent research has proposed it as a viable target for inhibition since it aids in flight and stress adaptation.MethodsThis study aimed to investigate benzothiazole derivatives as potential inhibitors of trehalase of Anopheles funestus (AfTre) and Anopheles gambiae (AgTre) using toxicity profiling, molecular docking, and dynamic simulation for future insecticidal intervention. A total of 4,214 benzothiazole-based compounds were obtained from the PubChem database and subjected to screening against the 3D modelled structure of AfTre and AgTre. Compounds with some toxicity levels were optimised, and the obtained lead compounds were further investigated through molecular docking studies. Furthermore, the best hit was subjected to parameters such as RMSD, RMSF, SASA, Rg, and hydrogen bond to confirm its stability when in a complex with AfTre, and these parameters were compared to that of validamycin A (control ligand).Results and discussionThe post-screening analysis showed binding affinities of −8.7 and −8.2 kcal/mol (compound 1), −8.2 and −7.4 kcal/mol (compound 2), compared to −6.3 and −5.1 kcal/mol (Validamycin A, a known inhibitor) against AfTre and AgTre, respectively. The molecular dynamics simulation showed that compound 1 (the best hit) had good stability when in complex with AfTre. These findings suggest that these best hits can serve as potential inhibitors for the development of novel insecticides in the control of malaria vectors.

Abstract A series of arecoline derivatives with amino acid moieties were designed and synthesised using an acylamide condensation strategy, taking arecoline as the foundational structure. The insecticidal efficacy of these compounds against Aphis craccivora and Tetranychus cinnabarinus was evaluated. Notably, derivatives 3h and 3i demonstrated superior insecticidal activity compared with arecoline. Additionally, 3h and 3i showed good fungicidal effectiveness against two types of plant fungi. Moreover, molecular docking analyses suggested that 3h and 3i could affect the nervous systems of A. craccivora and T. cinnabarinus by binding to neuronal nicotinic acetylcholine receptors. These findings suggest that compounds 3h and 3i represent promising leads for further development in insecticide and fungicide research.

The escalating phenomenon of bacterial resistance to antibiotics over time, coupled with the conse-quential detrimental effects of oxidative stress on cellular aging, and the usage of pesticides with vary-ing degrees of toxicity, thereby impacting both human health and the environment, represents a pressing global concern. Consequently, researchers are compelled to identify novel biomolecules de-rived from plants and their derivatives that possess antibacterial, antioxidant, and insecticidal proper-ties. The olive tree (Olea europaea L.), a fruit-bearing tree within the Oleaceae family, characterized by its olives, has been cultivated for millennia, particularly in Mediterranean regions, with its leaves being primarily employed for their multifarious therapeutic attributes. In this investigation, extracts were procured from olive leaves through employment of the Soxhlet apparatus, followed by the quantifica-tion of total polyphenols and flavonoids. The assessment of the antioxidant potential of these extracts was conducted using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The antibacterial efficacy was evaluated via the disk diffusion method against six pathogenic bacterial strains, namely Staphylococcus aureus, Escherichia coli, Acinetobacter baumannii, Salmonella sp, Klebsiella pneumoniae, and Pseudo-monas aeruginosa. Additionally, the in vitro aphicide activity of Olea europaea L. extracts were investi-gated at concentrations of 0.5%, 1%, 1.5%, 2%, and 2.5% against the black bean aphid, Aphis fabae Scop. The findings of this study suggest that olive leaf extracts exhibit robust antioxidant properties and dis-play modest antibacterial activity against pathogenic agents. Hence, these extracts are strongly en-dorsed for their potential role as eco-friendly antioxidants, and owing to their modest yet efficient in-sect-repelling attributes, they can be utilized as a sustainable, low-impact insecticide in the ecological engineering approach to controlling black aphids in bean crops. Therefore, the utilization of olive tree-derived extracts is encouraged.

Abstract Bacillus thuringiensis Cry2Ab toxin was a widely used bioinsecticide to control lepidopteran pests all over the world. In the present study, engineering of Bacillus thuringiensis Cry2Ab toxin was performed for improved insecticidal activity using site-specific saturation mutation. Variants L183I were screened with lower LC50 (0.129 µg/cm2) against P. xylostella when compared to wild-type Cry2Ab (0.267 µg/cm2). To investigate the molecular mechanism behind the enhanced activity of variant L183I, the activation, oligomerization and pore-formation activities of L183I were evaluated, using wild-type Cry2Ab as a control. The results demonstrated that the proteolytic activation of L183I was the same as that of wild-type Cry2Ab. However, variant L183I displayed higher oligomerization and pore-formation activities, which was consistence with its increased insecticidal activity. The current study demonstrated that the insecticidal activity of Cry2Ab toxin could be assessed using oligomerization and pore-formation activities, and the screened variant L183I with improved activity might contribute to Cry2Ab toxin’s future application.

A series of arecoline derivatives with amino acid moieties were designed and synthesised using an acylamide condensation strategy, taking arecoline as the foundational structure. The insecticidal efficacy of these compounds against Aphis craccivora and Tetranychus cinnabarinus was evaluated. Notably, derivatives 3h and 3i demonstrated superior insecticidal activity compared with arecoline. Additionally, 3h and 3i showed good fungicidal effectiveness against two types of plant fungi. Moreover, molecular docking analyses suggested that 3h and 3i could affect the nervous systems of A. craccivora and T. cinnabarinus by binding to neuronal nicotinic acetylcholine receptors. These findings suggest that compounds 3h and 3i represent promising leads for further development in insecticide and fungicide research. [ABSTRACT FROM AUTHOR]

Essential oils (EOs) extracted from various medicinal plants offer a promising alternative to non-selective chemical substances commonly employed in conventional agriculture. Their chemical composition includes several classes of chemical compounds with beneficial properties, such as monoterpenes, sesquiterpenes, and phenylpropanoids, which can selectively control microbiological elements in soil and plants. The aim of the present study was to evaluate the essential oils and floral waters obtained from a new variety of marigold (Tagetes patula L., fam. Asteraceae, "Nanuk" variety) across various parameters, including biochemical characterization using GC-MS, antioxidant activity evaluated under three methods (DPPH, ABTS, FRAP), antimicrobial properties (for three G− bacteria: Perctobacterium carotovorum, Pseudomonas marginalis, Pseudomonas syringae and against three phytopathogenic fungi: Rhizoctonia solani, Fusarium oxysporum, Botrytis cinerea), and insecticidal activity. The results showed that when applied in high concentrations, marigold essential oil has a potential bactericidal effect on P. carotovorum, as well as a potential fungicidal effect on B. cinerea. [ABSTRACT FROM AUTHOR]