Effects of high doses of zearalenone on some antioxidant enzymes and locomotion of Tenebrio molitor larvae (Coleoptera: Tenebrionidae).

The mealworm Tenebrio molitor L. (Coleoptera: Tenebrionidae) feeds on wheat bran and is considered both a pest and an edible insect. Its larvae contain proteins and essential amino acids, fats, and minerals, making them suitable for animal and human consumption. Zearalenone (ZEA) is the mycotoxin most commonly associated with Fusarium spp. It is found in cereals and cereal products, so their consumption is a major risk for mycotoxin contamination. One of the most important effects of ZEA is the induction of oxidative stress, which leads to physiological and behavioral changes. This study deals with the effects of high doses of ZEA (10 and 20 mg/kg) on survival, molting, growth, weight gain, activity of antioxidant enzymes superoxide dismutase (SOD) and glutathione S-transferase (GST), and locomotion of mealworm larvae. Both doses of ZEA were found to (i) have no effect on survival, (ii) increase molting frequency, SOD, and GST activity, and (iii) decrease body weight and locomotion, with more pronounced changes at 20 mg/kg. These results indicated the susceptibility of T. molitor larvae to high doses of ZEA in feed.

Effects of ivermectin on development of Calliphora vicina, Robineau-Desvoidy 1830 (Diptera, Calliphoridae).

Ivermectin is one of the most widely used drugs for parasite control. Previous studies have shown a reduction in the abundance and diversity of "non-target" coprophilous organisms due to the presence of ivermectin (IVM) in bovine faecal matter (FM). Due to its breadth of behavioural habits, Calliphora vicina is a suitable dipteran species to evaluate the effects of IVM in FM. The aim of this work was to evaluate the effect of five concentrations of IVM in FM (3000, 300, 100, 30, and 3 ng/g) on the development of C. vicina. The following endpoints were evaluated: survival (between the first larval stage and emergence of new adults), larval development times to pupation and pupation times to adult, and adult emergence (% sex) and LC50. Sampling was performed from larval hatching at 60 and 120 min and at 3, 4, 5, and 12 h, and every 24 h specimens were weighed until pupae were observed. Data were analysed by ANOVA using a non-parametric Kruskal-Wallis test and as a function of elapsed development time and accumulated degree hours (ADH). Mortality at 3000 and 300 ng/g was 100% and 97%, respectively. There were statistically significant delays in adult emergence time (p = 0.0216) and in the ADH (p = 0.0431) between the control group (C) and 100 ng/g. The LC50 was determined at 5.6 ng/g. These results demonstrate the lethal and sub-lethal effects of IVM on C. vicina, while highlighting the usefulness of this species as a bioindicator for ecotoxicological studies.

Understanding the mechanism of action of protease inhibitors in controlling the growth of the Candida Genus: potential candidates for development of new antifungal molecules.

There is a growing imperative for research into alternative compounds for the treatment of the fungal infections. Thus, many studies have focused on the analysis of antifungal proteins and peptides from different plant sources. Among these molecules are protease inhibitors (PIs). Previously, PIs present in the peptide-rich fractions called PEF1, PEF2 and PEF3 were identified from Capsicum chinense seeds, which have strong activity against phytopathogenic fungi. The aim of this study was to evaluate the mechanism of action and antimicrobial activity of PIs from PEF2 and PEF3 on the growth of yeasts of the genus Candida. In this work, analyses of their antimicrobial activity and cell viability were carried out. Subsequently, the mechanism of action by which the PIs cause the death of the yeasts was evaluated. Cytotoxicity was assessed in vitro by erythrocytes lysis and in vivo in Galleria mellonella larvae. PEF2 and PEF3 caused 100% of the growth inhibition of C. tropicalis and C. buinensis. For C. albicans inhibition was approximately 60% for both fractions. The PEF2 and PEF3 caused a reduction in mitochondrial functionality of 54% and 46% for C. albicans, 26% and 30% for C. tropicalis, and 71% and 68% for C. buinensis, respectively. These fractions induced morphological alterations, led to membrane permeabilization, elevated ROS levels, and resulted in necrotic cell death in C. tropicalis, whilst demonstrating low toxicity toward host cells. From the results obtained here, we intend to contribute to the understanding of the action of PIs in the control of fungal diseases of medical importance.

Bioassay-Guided and DeepSAT-Driven Precise Mining of Monoterpenoid Coumarin Derivatives with Antifeedant Effects from the Leaves of Ailanthus altissima.

Demand for the exploration of botanical pesticides continues to increase due to the detrimental effects of synthetic chemicals on human health and the environment and the development of resistance by pests. Under the guidance of a bioactivity-guided approach and HSQC-based DeepSAT, 16 coumarin derivatives were discovered from the leaves of Ailanthus altissima (Mill.) Swingle, including seven undescribed monoterpenoid coumarins, three undescribed monoterpenoid phenylpropanoids, and two new coumarin derivatives. The structure and configurations of these compounds were established and validated via extensive spectroscopic analysis, acetonide analysis, and quantum chemical calculations. Biologically, 5 exhibited significant antifeedant activity toward the Plutella xylostella. Moreover, tyrosinase being closely related to the growth and development of larva, the inhibitory potentials of 5 against tyrosinase was evaluated in vitro and in silico. The bioactivity evaluation results highlight the prospect of 5 as a novel category of botanical insecticide.

Design of Inhibitors Targeting Chitin-Degrading Enzymes by Bioisostere Substitutions and Scaffold Hopping for Selective Control of Ostrinia furnacalis.

Chitin-degrading enzymes are critical components in regulating the molting process of the Asian corn borer and serve as potential targets for controlling this destructive pest of maize. Here, we used a scaffold-hopping strategy to design a series of efficient naphthylimide insecticides. Among them, compound 8c exhibited potent inhibition of chitinase from OfChi-h and OfChtI at low nanomolar concentrations (IC50 = 1.51 and 9.21 nM, respectively). Molecular docking simulations suggested that 8c binds to chitinase by mimicking the interaction of chitin oligosaccharide substrates with chitinase. At low ppm concentrations, compound 8c performed comparably to commercial insecticides in controlling the highly destructive plant pest, the Asian corn borer. Tests on a wide range of nontarget organisms indicate that compound 8c has very low toxicity. In addition, the effect of inhibitor treatment on the expression of genes associated with the Asian corn borer chitin-degrading enzymes was further investigated by quantitative real-time polymerase chain reaction. In conclusion, our study highlights the potential of 8c as a novel chitinase-targeting insecticide for effective control of the Asian corn borer, providing a promising solution in the quest for sustainable pest management.

Transcription Factors AhR and ARNT Regulate the Expression of CYP6SX1 and CYP3828A1 Involved in Insecticide Detoxification in Bradysia odoriphaga.

Aryl hydrocarbon receptor (AhR) and aryl hydrocarbon receptor nuclear translocator (ARNT) mediate the responses of adaptive metabolism to various xenobiotics. Here, we found that BoAhR and BoARNT are highly expressed in the midgut of Bradysia odoriphaga larvae. The expression of BoAhR and BoARNT was significantly increased after exposure to imidacloprid and phoxim. The knockdown of BoAhR and BoARNT significantly decreased the expression of CYP6SX1 and CYP3828A1 as well as P450 enzyme activity and caused a significant increase in the sensitivity of larvae to imidacloprid and phoxim. Exposure to ß-naphthoflavone (BNF) significantly increased the expression of BoAhR, BoARNT, CYP6SX1, and CYP3828A1 as well as P450 activity and decreased larval sensitivity to imidacloprid and phoxim. Furthermore, CYP6SX1 and CYP3828A1 were significantly induced by imidacloprid and phoxim, and the silencing of these two genes significantly reduced larval tolerance to imidacloprid and phoxim. Taken together, the BoAhR/BoARNT pathway plays key roles in larval tolerance to imidacloprid and phoxim by regulating the expression of CYP6SX1 and CYP3828A1.

Facile synthesis of silver and gold nanoparticles using mangrove (Avicennia marina) leaves extract and its cytotoxicity and larvicidal activity.

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.

Manganese Overexposure Alters Neurogranin Expression and Causes Behavioral Deficits in Larval Zebrafish.

Manganese (Mn), a cofactor for various enzyme classes, is an essential trace metal for all organisms. However, overexposure to Mn causes neurotoxicity. Here, we evaluated the effects of exposure to Mn chloride (MnCl2) on viability, morphology, synapse function (based on neurogranin expression) and behavior of zebrafish larvae. MnCl2 exposure from 2.5 h post fertilization led to reduced survival (60%) at 5 days post fertilization. Phenotypical changes affected body length, eye and olfactory organ size, and visual background adaptation. This was accompanied by a decrease in both the fluorescence intensity of neurogranin immunostaining and expression levels of the neurogranin-encoding genes nrgna and nrgnb, suggesting the presence of synaptic alterations. Furthermore, overexposure to MnCl2 resulted in larvae exhibiting postural defects, reduction in motor activity and impaired preference for light environments. Following the removal of MnCl2 from the fish water, zebrafish larvae recovered their pigmentation pattern and normalized their locomotor behavior, indicating that some aspects of Mn neurotoxicity are reversible. In summary, our results demonstrate that Mn overexposure leads to pronounced morphological alterations, changes in neurogranin expression and behavioral impairments in zebrafish larvae.

Discovering allatostatin type-C receptor specific agonists.

Currently, there is no pesticide available for the selective control of the pine processionary moth (Thaumetopoea pityocampa-specific), and conventional methods typically rely on mechanical techniques such as pheromone traps or broad-spectrum larvicidal chemicals. As climate change increases the range and dispersion capacity of crop and forest pests, outbreaks of the pine processionary occur with greater frequency and significantly impact forestry and public health. Our study is carried out to provide a T. pityocampa-specific pesticide targeting the Allatostatin Type-C Receptor (AlstR-C). We use a combination of computational biology methods, a cell-based screening assay, and in vivo toxicity and side effect assays to identify, for the first time, a series of AlstR-C ligands suitable for use as T. pityocampa-specific insecticides. We further demonstrate that the novel AlstR-C targeted agonists are specific to lepidopteran larvae, with no harmful effects on coleopteran larvae or adults. Overall, our study represents an important initial advance toward an insect GPCR-targeted next-generation pesticide design. Our approach may apply to other invertebrate GPCRs involved in vital metabolic pathways.

Metabolism and cytotoxicity studies of the two hallucinogens 1cP-LSD and 4-AcO-DET in human liver and zebrafish larvae models using LC-HRMS/MS and a high-content screening assay.

The continuous emergence of new psychoactive substances (NPS) attracted a great deal of attention within recent years. Lately, the two hallucinogenic NPS 1cP-LSD and 4-AcO-DET have appeared on the global market. Knowledge about their metabolism to identify potential metabolic targets for analysis and their cytotoxic properties is lacking. The aim of this work was thus to study their in vitro and in vivo metabolism in pooled human liver S9 fraction (pHLS9) and in zebrafish larvae (ZL) by means of liquid chromatography-high-resolution tandem mass spectrometry. Monooxygenases involved in the initial metabolic steps were elucidated using recombinant human isozymes. Investigations on their cytotoxicity were performed on the human hepatoma cell line HepG2 using a multiparametric, fluorescence-based high-content screening assay. This included measurement of CYP-enzyme mediated effects by means of the unspecific CYP inhibitor 1-aminbenzotriazole (ABT). Several phase I metabolites of both compounds and two phase II metabolites of 4-AcO-DET were produced in vitro and in vivo. After microinjection of 1cP-LSD into the caudal vein of ZL, three out of seven metabolites formed in pHLS9 were also detected in ZL. Twelve 4-AcO-DET metabolites were identified in ZL after exposure via immersion bath and five of them were found in pHLS9 incubations. Notably, unique metabolites of 4-AcO-DET were only produced by ZL, whereas 1cP-LSD specific metabolites were found both in ZL and in pHLS9. No toxic effects were observed for 1cP-LSD and 4-AcO-DET in HepG2 cells, however, two parameters were altered in incubations containing 4-AcO-DET together with ABT compared with incubations without ABT but in concentrations far above expected in vivo concentration. Further investigations should be done with other hepatic cell lines expressing higher levels of CYP enzymes.

Jnk1 and downstream signalling hubs regulate anxiety-like behaviours in a zebrafish larvae phenotypic screen.

Current treatments for anxiety and depression show limited efficacy in many patients, indicating the need for further research into the underlying mechanisms. JNK1 has been shown to regulate anxiety- and depressive-like behaviours in mice, however the effectors downstream of JNK1 are not known. Here we compare the phosphoproteomes from wild-type and Jnk1-/- mouse brains and identify JNK1-regulated signalling hubs. We next employ a zebrafish (Danio rerio) larvae behavioural assay to identify an antidepressant- and anxiolytic-like (AA) phenotype based on 2759 measured stereotypic responses to clinically proven antidepressant and anxiolytic (AA) drugs. Employing machine learning, we classify an AA phenotype from extracted features measured during and after a startle battery in fish exposed to AA drugs. Using this classifier, we demonstrate that structurally independent JNK inhibitors replicate the AA phenotype with high accuracy, consistent with findings in mice. Furthermore, pharmacological targeting of JNK1-regulated signalling hubs identifies AKT, GSK-3, 14-3-3 ζ/ε and PKCε as downstream hubs that phenocopy clinically proven AA drugs. This study identifies AKT and related signalling molecules as mediators of JNK1-regulated antidepressant- and anxiolytic-like behaviours. Moreover, the assay shows promise for early phase screening of compounds with anti-stress-axis properties and for mode of action analysis.

Can Salvinia auriculata bioremediate the toxic effects of Fipronil 800wg on the tadpoles of Dendropsophus minutus?

Worldwide, the indiscriminate and escalating application of pesticides has led to extensive impacts on both the environment and non-target organisms. Phytoremediation, which employs plants to decontaminate environments, is a potential strategy for the mitigation of this damage. The present study assessed the phytoremedial potential of Salvinia auriculata, an aquatic macrophyte known to be effective for the removal of environmental contaminants. In the laboratory, Dendropsophus minutus tadpoles were exposed to different concentrations (0.035, 0.1, 1.0, and 1.5 mg/l) of the commercial insecticide Fipronil 800wg in two treatments - (i) simple exposure for 96 h, and (ii) exposure for 168 h in aquariums containing S. auriculata. In the first experiment, a mortality rate of 33.3 % was recorded at the highest Fipronil concentration (1.5 mg/l), and genotoxic parameters increased at all concentrations except 0.035 mg/L, in comparison with the control. In the second experiment, phytoremediation occurred at all the concentrations tested, with lower frequencies of cells with micronuclei, and binucleated, anucleated, and pyknotic nuclei being observed, in comparison with the first experiment. These findings highlight the potential effectiveness of S. auriculata for the phytoremediation of environments contaminated by pesticides and contribute to the understanding of the benefits of this approach for the protection and preservation of aquatic biodiversity.

Evaluating the toxicity of estetrol, 17α-ethinylestradiol, and their combination with drospirenone on zebrafish larvae: A behavioural and proteomic study.

OBJECTIVE: To characterise and compare the toxicity of estetrol (E4) and 17α-ethinylestradiol (EE2), and their respective mixture with the progestin drospirenone (DRSP) in zebrafish (Danio rerio) embryos. METHODS: Zebrafish embryos were exposed to E4, EE2, DRSP, E4+DRSP, and EE2+DRSP in a fish embryo acute toxicity (FET) test. A second test examined behavioural responses and, using label-free proteomics, identified changes in protein expression in response to hormonal treatments, across a range of concentrations, including those that are considered to be environmentally relevant. RESULTS: In the FET test, no effects were found from E4 at concentrations ≤100 mg/L, while EE2 induced mortality and morphological abnormalities at concentrations of 1-2 mg/L. In the behavioural test, exposure to 30 ng/L EE2 (∼200 × predicted environmental concentration - PEC) resulted in hypoactivity in fish larvae and exposure to 0.3 ng/L EE2 (∼2 × PEC) led to quantitative changes in protein abundance, revealing potential impacts on RNA processing and protein synthesis machinery. Exposure to E4 did not alter behaviour, but several groups of proteins were modulated, mainly at 710 ng/L (∼200 × PEC), including proteins involved in oxidative phosphorylation. When combined with DRSP, EE2 induced reduced effects on behaviour and proteomic responses, suggesting an antagonistic effect of DRSP. E4+DRSP induced no significant effects on behaviour or proteomic profiles at tested concentrations. CONCLUSIONS: These findings suggest that E4-based combined oral contraceptives present a more favourable environmental profile than EE2-based contraceptives, particularly during the early developmental stages of fish.

Phytomediated stress modulates antioxidant status, induces overexpression of CYP6M2, Hsp70, α-esterase, and suppresses the ABC transporter in Anopheles gambiae (sensu stricto) exposed to Ocimum tenuiflorum extracts.

The incorporation of phytoactive compounds in the management of malarial vectors holds promise for the development of innovative and efficient alternatives. Nevertheless, the molecular and physiological responses that these bioactive substances induce remain underexplored. This present study investigated the toxicity of different concentrations of aqueous and methanol extracts of Ocimum tenuiflorum against larvae of Anopheles gambiae (sensu stricto) and unraveled the possible underlying molecular pathways responsible for the observed physiological effects. FTIR and GCMS analyses of phytoactive compounds in aqueous and methanol crude extracts of O. tenuiflorum showed the presence of OH stretching vibration, C = C stretching modes of aromatics and methylene rocking vibration; ring deformation mode with high levels of trans-ß-ocimene, 3,7-dimethyl-1,3,6-octatriene in aqueous extract and 4-methoxy-benzaldehyde, 1,3,5-trimethyl-cyclohexane and o-cymene in methanol extract. The percentage mortality upon exposure to methanol and aqueous extracts of O. tenuiflorum were 21.1% and 26.1% at 24 h, 27.8% and 36.1% at 48 h and 36.1% and 45% at 72 h respectively. Using reverse transcription quantitative polymerase chain reaction (RT-qPCR), down-regulation of ABC transporter, overexpression of CYP6M2, Hsp70, and α-esterase, coupled with significantly increased levels of SOD, CAT, and GSH, were observed in An. gambiae (s.s.) exposed to aqueous and methanol extracts of O. tenuiflorum as compared to the control. Findings from this study have significant implications for our understanding of how An. gambiae (s.s.) larvae detoxify phytoactive compounds.

Toxic effects of acaricide fenazaquin on development, hemolymph metabolome, and gut microbiome of honeybee (Apis mellifera) larvae.

Fenazaquin, a potent insecticide widely used to control phytophagous mites, has recently emerged as a potential solution for managing Varroa destructor mites in honeybees. However, the comprehensive impact of fenazaquin on honeybee health remains insufficiently understood. Our current study investigated the acute and chronic toxicity of fenazaquin to honeybee larvae, along with its influence on larval hemolymph metabolism and gut microbiota. Results showed that the acute median lethal dose (LD50) of fenazaquin for honeybee larvae was 1.786 µg/larva, and the chronic LD50 was 1.213 µg/larva. Although chronic exposure to low doses of fenazaquin exhibited no significant effect on larval development, increasing doses of fenazaquin resulted in significant increases in larval mortality, developmental time, and deformity rates. At the metabolic level, high doses of fenazaquin inhibited nucleotide, purine, and lipid metabolism pathways in the larval hemolymph, leading to energy metabolism disorders and physiological dysfunction. Furthermore, high doses of fenazaquin reduced gut microbial diversity and abundance, characterized by decreased relative abundance of functional gut bacterium Lactobacillus kunkeei and increased pathogenic bacterium Melissococcus plutonius. The disrupted gut microbiota, combined with the observed gut tissue damage, could potentially impair food digestion and nutrient absorption in the larvae. Our results provide valuable insights into the complex and diverse effects of fenazaquin on honeybee larvae, establishing an important theoretical basis for applying fenazaquin in beekeeping.

Developmental and biochemical markers of the impact of pollutant mixtures under the effect of Global Climate Change.

This study investigates the combined impact of microplastics (MP) and Chlorpyriphos (CPF) on sea urchin larvae (Paracentrotus lividus) under the backdrop of ocean warming and acidification. While the individual toxic effects of these pollutants have been previously reported, their combined effects remain poorly understood. Two experiments were conducted using different concentrations of CPF (EC10 and EC50) based on previous studies from our group. MP were adsorbed in CPF to simulate realistic environmental conditions. Additionally, water acidification and warming protocols were implemented to mimic future ocean conditions. Sea urchin embryo toxicity tests were conducted to assess larval development under various treatment combinations of CPF, MP, ocean acidification (OA), and temperature (OW). Morphometric measurements and biochemical analyses were performed to evaluate the effects comprehensively. Results indicate that combined stressors lead to significant morphological alterations, such as increased larval width and reduced stomach volume. Furthermore, biochemical biomarkers like acetylcholinesterase (AChE), glutathione S-transferase (GST), and glutathione reductase (GRx) activities were affected, indicating oxidative stress and impaired detoxification capacity. Interestingly, while temperature increase was expected to enhance larval growth, it instead induced thermal stress, resulting in lower growth rates. This underscores the importance of considering multiple stressors in ecological assessments. Biochemical biomarkers provided early indications of stress responses, complementing traditional growth measurements. The study highlights the necessity of holistic approaches when assessing environmental impacts on marine ecosystems. Understanding interactions between pollutants and environmental stressors is crucial for effective conservation strategies. Future research should delve deeper into the impacts at lower biological levels and explore adaptive mechanisms in marine organisms facing multiple stressors. By doing so, we can better anticipate and mitigate the adverse effects of anthropogenic pollutants on marine biodiversity and ecosystem health.

Effects of diphenhydramine exposure on reproduction of mature Japanese medaka (Oryzias latipes).

Diphenhydramine (DPH) is an antihistamine drug. It has been frequently detected in the environment, because it is not completely degraded in wastewater treatment plants. Recent studies have shown the adverse effects of DPH exposure to various aquatic organisms; however, its chronic effects on fish have been poorly elucidated. In this study, several pairs of mature Japanese medaka (Oryzias latipes) were exposed to DPH for a long period to determine the effects of DPH exposure on the subsequent generations, number of spawned and fertilized eggs, expression of sex-related genes, feeding behavior, embryo development, hatching rate, malformations among the hatched larvae, and mortality rate. The number of spawned eggs significantly decreased, when the parent fish were continuously exposed to 31.6 µg/L DPH for over 46 days. DPH exposure also altered the feeding behavior of medaka individuals, and increased the larval mortality rate. The effects of DPH exposure to fish may occur to some extent in the actual aquatic environment, although the risk evaluations in the field are limited.

Evaluating anthelmintic, anti-platelet, and anti-coagulant activities, and identifying the bioactive phytochemicals of Amaranthus blitum L.

BACKGROUND: Highlighting affordable alternative crops that are rich in bioactive phytoconstituents is essential for advancing nutrition and ensuring food security. Amaranthus blitum L. (AB) stands out as one such crop with a traditional history of being used to treat intestinal disorders, roundworm infections, and hemorrhage. This study aimed to evaluate the anthelmintic and hematologic activities across various extracts of AB and investigate the phytoconstituents responsible for these activities. METHODS: In vitro anthelmintic activity against Trichinella spiralis was evaluated in terms of larval viability reduction. The anti-platelet activities were assessed based on the inhibitory effect against induced platelet aggregation. Further, effects on the extrinsic pathway, the intrinsic pathway, and the ultimate common stage of blood coagulation, were monitored through measuring blood coagulation parameters: prothrombin time (PT), activated partial thromboplastin time (aPTT), and thrombin time (TT), respectively. The structures of isolated compounds were elucidated by spectroscopic analysis. RESULTS: Interestingly, a previously undescribed compound (19), N-(cis-p-coumaroyl)-ʟ-tryptophan, was isolated and identified along with 21 known compounds. Significant in vitro larvicidal activities were demonstrated by the investigated AB extracts at 1 mg/mL. Among tested compounds, compound 18 (rutin) displayed the highest larvicidal activity. Moreover, compounds 19 and 20 (N-(trans-p-coumaroyl)-ʟ-tryptophan) induced complete larval death within 48 h. The crude extract exhibited the minimal platelet aggregation of 43.42 ± 11.69%, compared with 76.22 ± 14.34% in the control plasma. Additionally, the crude extract and two compounds 19 and 20 significantly inhibited the extrinsic coagulation pathway. CONCLUSIONS: These findings extend awareness about the nutritional value of AB as a food, with thrombosis-preventing capabilities and introducing a promising source for new anthelmintic and anticoagulant agents.

Six-year monitoring of pesticide resistance in the Colorado potato beetle (Leptinotarsa decemlineata Say) during a neonicotinoid restriction period.

The Colorado potato beetle (CPB; Leptinotarsa decemlineata) is an important potato pest with known resistance to pyrethroids and organophosphates in Czechia. Decreased efficacy of neonicotinoids has been observed in last decade. After the restriction of using chlorpyrifos, thiacloprid and thiamethoxam by EU regulation, growers seek for information about the resistance of CPB to used insecticides and recommended antiresistant strategies. The development of CPB resistance to selected insecticides was evaluated in bioassays in 69 local populations from Czechia in 2017-2022 and in 2007-2022 in small plot experiments in Zabcice in South Moravia. The mortality in each subpopulation in the bioassays was evaluated at the field-recommended rates of insecticides to estimate the 50% and 90% lethal concentrations (LC50 and LC90, respectively). High levels of CPB resistance to lambda-cyhalothrin and chlorpyrifos were demonstrated throughout Czechia, without significant changes between years and regions. The average mortality after application of the field-recommended rate of lambda-cyhalothrin was influenced by temperature before larvae were sampled for bioassays and decreased with increasing temperature in June. Downwards trends in the LC90 values of chlorpyrifos and the average mortality after application of the field-recommended rate of acetamiprid in the bioassay were recorded over a 6-year period. The baseline LC50 value (with 95% confidence limit) of 0.04 mg/L of chlorantraniliprole was established for Czech populations of CPBs for the purpose of resistance monitoring in the next years. Widespread resistance to pyrethroids, organophosphates and neonicotinoids was demonstrated, and changes in anti-resistant strategies to control CPBs were discussed.

Sublethal effects of a commercial Bt product and Bt cotton flowers on the bollworm (Helicoverpa zea) with impacts to predation from a lady beetle (Hippodamia convergens).

Insecticidal Bacillus thuringiensis Berliner (Bt) toxins produced by transgenic cotton (Gossypium hirsutum L.) plants have become an essential component of cotton pest management. Bt toxins are the primary management tool in transgenic cotton for lepidopteran pests, the most important of which is the bollworm (Helicoverpa zea Boddie) (Lepidoptera: Noctuidae) in the United States (U.S.). However, bollworm larvae that survive after consuming Bt toxins may experience sublethal effects, which could alter interactions with other organisms, such as natural enemies. Experiments were conducted to evaluate how sublethal effects of a commercial Bt product (Dipel) incorporated into artificial diet and from Bt cotton flowers impact predation from the convergent lady beetle (Hippodamia convergens Guérin-Méneville) (Coleoptera: Coccinellidae), common in cotton fields of the mid-southern U.S. Sublethal effects were detected through reduced weight and slower development in bollworm larvae which fed on Dipel incorporated into artificial diet, Bollgard II, and Bollgard 3 cotton flowers. Sublethal effects from proteins incorporated into artificial diet were found to significantly alter predation from third instar lady beetle larvae. Predation of bollworm larvae also increased significantly after feeding for three days on a diet incorporated with Bt proteins. These results suggest that the changes in larval weight and development induced by Bt can be used to help predict consumption of bollworm larvae by the convergent lady beetle. These findings are essential to understanding the potential level of biological control in Bt cotton where lepidopteran larvae experience sublethal effects.