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1.
Molecules ; 26(14)2021 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-34299388

RESUMO

In a project designed to investigate the specific and infraspecific taxa of Matthiola endemic to Sicily (Italy) as new potential sources of bioactive compounds in this work, the infraspecific taxa of Matthiola fruticulosa were studied, namely, subsp. fruticulosa and subsp. coronopifolia. HPLC-PDA/ESI-MS and SPME-GC/MS analyses of hydroalcoholic extracts obtained from the aerial parts of the two subspecies led to the detection of 51 phenolics and 61 volatile components, highlighting a quite different qualitative-quantitative profile. The antioxidant properties of the extracts were explored through in vitro methods: 1,1-diphenyl-2-picrylhydrazyl (DPPH), reducing power and Fe2+ chelating activity assays. The results of the antioxidant tests showed that the extracts possess a different antioxidant ability: particularly, the extract of M. fruticulosa subsp. fruticulosa exhibited higher radical scavenging activity than that of subsp. coronopifolia (IC50 = 1.25 ± 0.02 mg/mL and 2.86 ± 0.05 mg/mL), which in turn displayed better chelating properties (IC50 = 1.49 ± 0.01 mg/mL and 0.63 ± 0.01 mg/mL). Lastly, Artemia salina lethality bioassay was performed for toxicity assessment. The results of the bioassay showed lack of toxicity against brine shrimp larvae for both extracts. The data presented indicate the infraspecific taxa of M. fruticulosa as new and safe sources of antioxidant compounds.


Assuntos
Antioxidantes/toxicidade , Brassicaceae/química , Larva/crescimento & desenvolvimento , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/toxicidade , Extratos Vegetais/toxicidade , Animais , Artemia , Larva/efeitos dos fármacos , Sicília , Testes de Toxicidade
2.
J Chem Ecol ; 47(7): 664-679, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34196857

RESUMO

Larval Diaphania indica (Saunders) (Lepidoptera: Crambidae) cause complete defoliation of Trichosanthes anguina L. and reduce crop yield in India. Females lay eggs on the leaf surface, and therefore leaf surface waxes are potentially involved in host selection. Alkanes and free fatty acids are the major constituents of leaf surface waxes, so a study was conducted to determine whether these wax constituents from three T. anguina cultivars (MNSR-1, Baruipur Long, and Polo No.1) could act as short-range attractants and oviposition stimulants in D. indica females. Twenty n-alkanes from n-C14 to n-C36 and 13 free fatty acids from C12:0 to C21:0 were detected in the leaf surface waxes of these cultivars. Heptadecane and stearic acid were predominant among n-alkanes and free fatty acids, respectively, in these cultivars. Females showed attraction towards one leaf equivalent surface wax of each of these cultivars against solvent controls (petroleum ether) in Y-tube olfactometer bioassays. A synthetic blend of heptadecane, eicosane, hexacosane, and stearic acid, a synthetic blend of hexacosane and stearic acid, and a synthetic blend of pentadecane and stearic acid comparable to amounts present in one leaf equivalent surface wax of MNSR-1, Baruipur Long, and Polo No.1, respectively, were short-range attractants and oviposition stimulants in D. indica. Female egg laying responses were similar to each of these blends, providing information that could be used to developing baited traps in integrated pest management (IPM) programs.


Assuntos
Cucurbitaceae/metabolismo , Mariposas/fisiologia , Oviposição/efeitos dos fármacos , Ceras/farmacologia , Alcanos/análise , Alcanos/isolamento & purificação , Alcanos/farmacologia , Animais , Análise Discriminante , Ácidos Graxos não Esterificados/análise , Ácidos Graxos não Esterificados/isolamento & purificação , Ácidos Graxos não Esterificados/farmacologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Larva/efeitos dos fármacos , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Olfatometria , Folhas de Planta/metabolismo , Ceras/química , Ceras/isolamento & purificação
3.
Molecules ; 26(12)2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204264

RESUMO

The present research investigated the chemical characterization and insecticidal activity of n-Hexane extracts of Epaltes divaricata (NH-EDx) along with their chief derivatives n-Hexadecanoic acid (n-HDa) and n-Octadecanoic acid (n-ODa) against the dengue vector Aedes aegypti and lepidopteran pest Spodoptera litura. Chemical screening of NH-EDx through GC-MS analysis delivered nine major derivatives, and the maximum peak area percentage was observed in n-Hexadecanoic acid (14.63%) followed by n-Octadecadienoic acid (6.73%). The larvicidal activity of NH-EDx (1000 ppm), n-HDa (5 ppm), and n-ODa (5 ppm) against the A. aegypti and S. litura larvae showed significant mortality rate in a dose-dependent way across all the instars. The larvicidal activity was profound in the A. aegypti as compared to the S. litura across all the larval instars. The sublethal dosages of NH-EDx (500 ppm), n-HDa (2.5 ppm), and n-ODa (2.5 ppm) also showed alterations in the larval/pupal durations and adult longevity in both the insect pests. The enzyme activity revealed that the α- and ß-carboxylesterase levels were decreased significantly in both the insect pests, whereas the levels of GST and CYP450 uplifted in a dose-dependent manner of NH-EDx, n-HDa, and n-ODa. Correspondingly, midgut tissues such as the epithelial layer (EL), gut lumen (GL), peritrophic matrix (Pm), and brush border membrane (BBM) were significantly altered in their morphology across both A. aegypti and S. litura against the NH-EDx and their bioactive metabolites. NH-EDx and their bioactive metabolites n-HDa and n-ODa showed significant larvicidal, growth retardant, enzyme inhibition, and midgut toxicity effects against two crucial agriculturally and medically challenging insect pest of ecological importance.


Assuntos
Aedes/efeitos dos fármacos , Asteraceae/metabolismo , Extratos Vegetais/farmacologia , Spodoptera/efeitos dos fármacos , Animais , Asteraceae/efeitos dos fármacos , Culex/efeitos dos fármacos , Dengue/prevenção & controle , Hexanos/química , Inseticidas/farmacologia , Larva/efeitos dos fármacos , Mosquitos Vetores/efeitos dos fármacos , Folhas de Planta/química , Solventes/química
4.
Ecotoxicol Environ Saf ; 221: 112452, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34198186

RESUMO

Helicoverpa armigera (cotton bollworm) is one of the most destructive pests worldwide. Due to resistance to Bacillus thuringiensis and conventional insecticides, an effective management strategy to control this pest is urgently needed. Spinosad, a natural pesticide, is considered an alternative; however, the mechanism underlying the developmental effects of sublethal spinosad exposure remains elusive. In this study, the mechanism was examined using an insect model of H. armigera. Results confirmed that exposure to sublethal spinosad led to reduced larval wet weight, delayed larval developmental period, caused difficulty in molting, and deformed pupae. Further investigation demonstrated that exposure to sublethal spinosad caused a significant decrease in 20E titer and increase in JH titer, thereby leading to the discordance between 20E and JH titers, and consequently alteration in the expression levels of HR3 and Kr-h1. These results suggested that sublethal spinosad caused hormonal disorders in larvae, which directly affect insect development. Our study serves as a reference and basis for the toxicity evaluation of spinosad on molting and pupation in insect metamorphosis, which may contribute to identifying targets for effective control of cotton bollworm.


Assuntos
Inseticidas/toxicidade , Macrolídeos/toxicidade , Mariposas/efeitos dos fármacos , Animais , Combinação de Medicamentos , Larva/efeitos dos fármacos , Muda/efeitos dos fármacos , Mariposas/crescimento & desenvolvimento , Pupa/efeitos dos fármacos
5.
J Forensic Leg Med ; 81: 102207, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34214895

RESUMO

The determination of the post-mortem interval (PMI) is one of the main tasks of forensic entomology, where growth and stages of development of arthropods are used for PMI determination. It is well acknowledged that maggot development is significantly influenced by temperature. Attention has also been paid to the microbial populations of the cadaver, because toxic substances contained in the substrate can influence the microorganisms and affect arthropods growth and development. However, little is known about the influence of antibiotics taken during lifetime of a person on insect development after that persons death. The aim of this study was to test the hypothesis that the antibiotics ceftriaxone and levofloxacin cause inhibition of growth and delay of pupation of the blow fly Calliphora vomitoria, which would then lead to an incorrect determination of the post-mortem interval in forensic cases. It was found that maggot development was delayed by levofloxacin mixed in minced pork, where a mixture of both antibiotics increased this effect. The maggot growth in the samples with ceftriaxone was not delayed. Pupation was delayed in treatments with a mixture of both antibiotics. The mortality was reduced by separate or combined application of ceftriaxone and levofloxacin, which we attribute to a bactericidal effect of the antibiotics on maggot pathogens. Depending on the concentration of the antibiotics, an underestimation of the post-mortem interval between 24 and 48 h could be suspected. We conclude that antibiotics need to be considered if instar stages are to be used to determine the PMI and that some antibiotics may improve the breeding conditions of maggots.


Assuntos
Antibacterianos/farmacologia , Calliphoridae/crescimento & desenvolvimento , Ceftriaxona/farmacologia , Larva/efeitos dos fármacos , Levofloxacino/farmacologia , Animais , Entomologia Forense , Mudanças Depois da Morte
6.
Arch Insect Biochem Physiol ; 107(4): e21826, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34212404

RESUMO

The purpose of this study was to develop a new control method for Drosophila using saccharin sodium dihydrate (saccharin), an artificial sweetener that is safe for humans and the environment, and to elucidate its mode of action. In this study, we confirmed that saccharin can dose-dependently inhibit the development of or kill vinegar flies (VFs) and spotted wing Drosophila (SWDs). In addition, we found that low concentrations of saccharin induced a similar effect as starvation in Drosophila, whereas high concentrations of saccharin induced changes in the unfolded protein response (UPR) and autophagy signaling that were unlike starvation and inhibited development or killed the VF and the SWD by performing real-time quantitative polymerase chain reaction analyses. Spinosad is a widely used plant protection agent for SWD control. When saccharin was cotreated with 0.25-1.0 ppm spinosad, an additive insecticidal activity was observed only at high concentrations of saccharin. However, when saccharin was cotreated with 2.0 ppm spinosad, an additive insecticidal activity was observed at low concentrations of saccharin. Taken together, alteration of UPR and autophagy signaling represented the molecular basis underlying saccharin toxicity to Drosophila and concurrent spraying of an insecticide with saccharin could enhance the insecticidal activities.


Assuntos
Autofagia/efeitos dos fármacos , Drosophila/efeitos dos fármacos , Sacarina/toxicidade , Edulcorantes/toxicidade , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Animais , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Combinação de Medicamentos , Corpo Adiposo/efeitos dos fármacos , Feminino , Larva/efeitos dos fármacos , Macrolídeos , Masculino , Receptores de Superfície Celular/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sacarose
7.
Int J Mol Sci ; 22(14)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34299361

RESUMO

Zingiber officinale is one of the most frequently used medicinal herbs in Asia. Using rodent seizure models, it was previously shown that Zingiber officinale hydroethanolic extract exerts antiseizure activity, but the active constituents responsible for this effect have not been determined. In this paper, we demonstrated that Zingiber officinale methanolic extract exerts anticonvulsant activity in the pentylenetetrazole (PTZ)-induced hyperlocomotion assay in larval zebrafish. Next, we isolated 6-gingerol (6-GIN)-a major constituent of Zingiber officinale rhizoma. We observed that 6-GIN exerted potent dose-dependent anticonvulsant activity in the PTZ-induced hyperlocomotion seizure assay in zebrafish, which was confirmed electroencephalographically. To obtain further insight into the molecular mechanisms of 6-GIN antiseizure activity, we assessed the concentration of two neurotransmitters in zebrafish, i.e., inhibitory γ-aminobutyric acid (GABA) and excitatory glutamic acid (GLU), and their ratio after exposure to acute PTZ dose. Here, 6-GIN decreased GLU level and reduced the GLU/GABA ratio in PTZ-treated fish compared with only PTZ-bathed fish. This activity was associated with the decrease in grin2b, but not gabra1a, grin1a, gria1a, gria2a, and gria3b expression in PTZ-treated fish. Molecular docking to the human NR2B-containing N-methyl-D-aspartate (NMDA) receptor suggests that 6-GIN might act as an inhibitor and interact with the amino terminal domain, the glutamate-binding site, as well as within the ion channel of the NR2B-containing NMDA receptor. In summary, our study reveals, for the first time, the anticonvulsant activity of 6-GIN. We suggest that this effect might at least be partially mediated by restoring the balance between GABA and GLU in the epileptic brain; however, more studies are needed to prove our hypothesis.


Assuntos
Anticonvulsivantes/farmacologia , Catecóis/farmacologia , Álcoois Graxos/farmacologia , Gengibre/química , Pentilenotetrazol/farmacologia , Extratos Vegetais/farmacologia , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Epilepsia/tratamento farmacológico , Epilepsia/metabolismo , Larva/efeitos dos fármacos , Larva/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Convulsões/metabolismo , Peixe-Zebra , Ácido gama-Aminobutírico/metabolismo
8.
Int J Mol Sci ; 22(14)2021 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-34299368

RESUMO

BACKGROUND: Poisoning from pesticides can be extremely hazardous for non-invasive species, such as bees, and humans causing nearly 300,000 deaths worldwide every year. Several pesticides are recognized as endocrine disruptors compounds that alter the production of the normal hormones mainly by acting through their interaction with nuclear receptors (NRs). Among the insecticides, one of the most used is pyriproxyfen. As analogous to the juvenile hormone, the pyriproxyfen acts in the bee's larval growth and creates malformations at the adult organism level. METHODS: This work aims to investigate the possible negative effects of pyriproxyfen and its metabolite, the 4'-OH-pyriproxyfen, on human and bee health. We particularly investigated the mechanism of binding of pyriproxyfen and its metabolite with ultraspiracle protein/ecdysone receptor (USP-EcR) dimer of A. mellifera and the relative heterodimer farnesoid X receptor/retinoid X receptor alpha (FXR-RXRα) of H. sapiens using molecular dynamic simulations. RESULTS: The results revealed that pyriproxyfen and its metabolite, the 4'-OH- pyriproxyfen, stabilize each dimer and resulted in stronger binders than the natural ligands. CONCLUSION: We demonstrated the endocrine interference of two pesticides and explained their possible mechanism of action. Furthermore, in vitro studies should be carried out to evaluate the biological effects of pyriproxyfen and its metabolite.


Assuntos
Abelhas/efeitos dos fármacos , Abelhas/metabolismo , Piridinas/farmacologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Sequência de Aminoácidos , Animais , Simulação por Computador , Humanos , Inseticidas/farmacologia , Hormônios Juvenis/metabolismo , Larva/efeitos dos fármacos , Larva/metabolismo , Receptores de Esteroides/metabolismo
9.
Int J Mol Sci ; 22(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299005

RESUMO

Nanoparticles can interact with the complement system and modulate the inflammatory response. The effect of these interactions on the complement activity strongly depends on physicochemical properties of nanoparticles. The interactions of silver nanoparticles with serum proteins (particularly with the complement system components) have the potential to significantly affect the antibacterial activity of serum, with serious implications for human health. The aim of the study was to assess the influence of graphite oxide (GO) nanocomposites (GO, GO-PcZr(Lys)2-Ag, GO-Ag, GO-PcZr(Lys)2) on the antibacterial activity of normal human serum (NHS), serum activity against bacteria isolated from alveoli treated with nanocomposites, and nanocomposite sensitivity of bacteria exposed to serum in vitro (using normal human serum). Additionally, the in vivo cytotoxic effect of the GO compounds was determined with application of a Galleria mellonella larvae model. GO-PcZr(Lys)2, without IR irradiation enhance the antimicrobial efficacy of the human serum. IR irradiation enhances bactericidal activity of serum in the case of the GO-PcZr(Lys)2-Ag sample. Bacteria exposed to nanocomposites become more sensitive to the action of serum. Bacteria exposed to serum become more sensitive to the GO-Ag sample. None of the tested GO nanocomposites displayed a cytotoxicity towards larvae.


Assuntos
Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Grafite/química , Nanopartículas Metálicas/química , Nanocompostos/química , Óxidos/química , Soro/efeitos dos fármacos , Animais , Antibacterianos/química , Anti-Infecciosos/química , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/efeitos da radiação , Humanos , Raios Infravermelhos , Larva/efeitos dos fármacos , Larva/efeitos da radiação , Lepidópteros/efeitos dos fármacos , Lepidópteros/efeitos da radiação , Nanopartículas Metálicas/administração & dosagem , Nanocompostos/administração & dosagem , Soro/microbiologia , Prata/química
10.
J Chem Ecol ; 47(7): 680-688, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34101117

RESUMO

Past work shows a significant negative correlation between foliar oregonin concentration and western tent caterpillar (Malacosoma californicum Packard) feeding on red alder (Alnus rubra Bong.). Above an oregonin threshold of 20% leaf dry weight, little feeding by caterpillars is observed. Concentrations of defensive chemicals are influenced by plant genotype, environmental conditions, insect feeding, and the interactions of these factors. Our objective was to measure the effects of nitrogen (N) availability and wounding on foliar oregonin and condensed tannin concentrations in red alder genotypes. One-year-old seedlings from 100 half-sib red alder families were treated with two levels of ammonium nitrate (NH4NO3) for two growing seasons in a common garden. In the second year, leaves from 50 families from the fertilization experiment were used in a bioassay feeding experiment to determine the effects of N fertilization and genotype on WTC damage, and to identify a subset of 20 families with a range of damage to analyze for phytochemical composition. In separate experiments, wound-induction treatments were conducted outdoors and, in a greenhouse using the N treated trees in their third and fourth year, respectively. Foliar condensed tannin, oregonin and N concentrations were measured and ranked among the plant genotypes, and between the two N treatments and two wounding treatments. Results showed that oregonin and condensed tannin concentrations varied among the alder genotypes. Leaf N concentration was negatively correlated with concentration of oregonin. Neither of the measured phenolic compounds responded to wounding. The results suggest that red alder foliar oregonin and condensed tannin are likely constitutive defenses that are largely determined by genotype, and that the negative correlation of defense compounds with plant internal N status holds in this N-fixing tree.


Assuntos
Alnus/química , Diarileptanoides/química , Mariposas/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Taninos/análise , Alnus/genética , Alnus/crescimento & desenvolvimento , Animais , Cromatografia Líquida de Alta Pressão , Diarileptanoides/farmacologia , Fertilizantes/análise , Genótipo , Herbivoria/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Mariposas/fisiologia , Nitrogênio/química , Nitrogênio/metabolismo , Compostos Fitoquímicos/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Plântula , Espectrofotometria Ultravioleta , Taninos/farmacologia
11.
Arch Microbiol ; 203(7): 4587-4592, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34160628

RESUMO

The two-component Cry48Aa/Cry49Aa toxin produced by Lysinibacillus sphaericus shows specifically toxic to Culex quinquefasciatus mosquito larvae. Cry49Aa C-terminal domain is responsible for specific binding to the larval gut cell membrane, while its N-terminal domain is required for interaction with Cry48Aa. To investigate functional role of cysteine in Cry49Aa, four cysteine residues at positions 70, 91, 183, and 258 were substituted by alanine. All mutants showed similar crystalline morphology and comparable yield to that of the wild type except that the yield of the C91A mutant was low. Four cysteine residues did not involve in disulfide bond formation within or between Cry49Aa molecules. Cys91, Cys183, and Cys258 are essential for larvicidal activity against C. quinquefasciatus larvae, while Cys70 is not. Substitution at C91, C183, and C258 caused weaker Cry48Aa- Cry49Aa interaction, while mutations at C183 and C258 reduced the binding capacities to the larval gut cell membrane. Thus, Cysteine residues at position 91, 183, and 258 in Cry49Aa are required for full toxicity of Cry48Aa/Cry49Aa toxin.


Assuntos
Toxinas Bacterianas , Culex , Animais , Bacillaceae/genética , Bacillaceae/patogenicidade , Toxinas Bacterianas/genética , Toxinas Bacterianas/toxicidade , Culex/efeitos dos fármacos , Culex/microbiologia , Cisteína/genética , Larva/efeitos dos fármacos
12.
Ecotoxicol Environ Saf ; 220: 112385, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34082241

RESUMO

Sulfometuron methyl (SM) is a widely used herbicide and thus leading to accumulation in the environment. The toxicity assessments of SM in model organisms are currently rare. In the present study, zebrafish were utilized for evaluating the detrimental effects of SM in aquatic vertebrates. Zebrafish embryos were exposed to 0, 10, 20, and 40 mg/L SM from 5.5 to 72 h post-fertilization (hpf), respectively. Consequently, SM exposure resulted in increasing the mortality rate and reducing hatching rate in larval zebrafish at 10, 20, and 40 mg/L SM-treated groups. The reduced numbers of immune cells (neutrophils and macrophages) were observed after SM exposure by a dose-dependent manner. The inflammatory responses (TLR4, MYD88, IL-1ß, IL-6, IL-8, IFN-γ, IL-10, and TGF-ß) were measured to estimate immune responses. Anti-inflammatory factors (IL-10 and TGF-ß) were down-regulated in all the treated groups and significantly altered at 40 mg/L exposure group. Additionally, behavioral tests suggested that SM treatment significantly increased the total distance, average speed, and maximum acceleration of larval zebrafish during light-dark transition and subsequently enzymology test displayed the same trend to locomotor behaviors. The content significantly increased in oxidative stress, as reflected in ROS level in all the treated groups. The numbers of cell apoptosis were significantly increased at 20, and 40 mg/L and the highest concentration group induced the substantial increment (P < 0.001) of apoptosis-related genes including p53, Bax/Bcl-2, caspase-9, and caspase-3. In summary, our results demonstrated that exposure to SM caused toxicity of development, immune system, locomotor behavior, oxidative stress, and cell apoptosis at the early developmental stages of zebrafish.


Assuntos
Embrião não Mamífero/efeitos dos fármacos , Herbicidas/toxicidade , Compostos de Sulfonilureia/toxicidade , Peixe-Zebra/crescimento & desenvolvimento , Animais , Apoptose/efeitos dos fármacos , Catalase/metabolismo , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Larva/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio , Superóxido Dismutase/metabolismo , Poluentes Químicos da Água/toxicidade
13.
Parasitol Res ; 120(7): 2351-2356, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34100111

RESUMO

Chrysomya megacephala (Fabricius, 1794) (Diptera, Calliphoridae) acts as a vector of many disease-causing pathogens. It causes myiasis in human beings and other living vertebrates. In the present study, the effect of a juvenile hormone analog (JHA), fenoxycarb, was evaluated on pupal-adult transformation by exposing pupae (0 and 1-day-old) of blowfly. Pupae were topically treated with different concentrations of the compound, viz., 20, 40, and 80 µg/µl applied on the posterior dorsum with the help of a micropipette. The effects comprised various developmental aberrations, such as delayed pupal-adult ecdysis duration, pupal mortality, formation of pupal-adult intermediates, eclosion failure, reduced adult emergence, and formation of abnormal adults. The freshly molted pupae (0 day) were more susceptible as compared to 1-day-old pupae. Pupal mortality was highest at 80 µg. Normal adult emergence was completely inhibited at day 0 pupae treated with 80 µg of the fenoxycarb. These results demonstrate that fenoxycarb was capable of successfully inhibiting the pupal-adult transformation, and thus, it can be used to control this myiasis-causing agent.


Assuntos
Calliphoridae/efeitos dos fármacos , Inseticidas/farmacologia , Hormônios Juvenis/farmacologia , Fenilcarbamatos/farmacologia , Adulto , Animais , Calliphoridae/crescimento & desenvolvimento , Humanos , Inseticidas/uso terapêutico , Hormônios Juvenis/uso terapêutico , Larva/efeitos dos fármacos , Miíase/tratamento farmacológico , Miíase/parasitologia , Fenilcarbamatos/uso terapêutico , Pupa/efeitos dos fármacos , Pupa/crescimento & desenvolvimento
14.
Methods Mol Biol ; 2326: 47-54, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34097260

RESUMO

Drosophila melanogaster, the fruit fly, has been widely used in biological investigation as an invertebrate alternative to mammals for its various advantages compared to other model organisms, which include short life cycle, easy handling, high prolificacy, and great availability of substantial genetic information. The behavior of Drosophila melanogaster is closely related to its growth, which can reflect the physiological conditions of Drosophila. We have optimized simple and robust behavioral assays for determining the larvae survival, adult climbing ability (mobility assay), reproductive behavior, and lifespan of Drosophila. In this chapter, we present the step-by-step detailed method for studying Drosophila behavior.


Assuntos
Drosophila melanogaster/fisiologia , Animais , Bioensaio/métodos , Drosophila melanogaster/efeitos dos fármacos , Drosophila melanogaster/crescimento & desenvolvimento , Feminino , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Locomoção/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Masculino , Reprodução/efeitos dos fármacos , Testes de Toxicidade/métodos
15.
Methods Mol Biol ; 2326: 55-66, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34097261

RESUMO

Exposure to multiple stressors often results in higher toxicity than one stressor alone. Examining joint effects of multiple stressors could provide more realistic exposure scenarios and a better understanding of the combined effects. In amphibian toxicology, simultaneous exposure to some pesticides and ultraviolet B (UVB) radiation has been suggested to be detrimental and more harmful in amphibian early-life stages than either stressor alone. Therefore, it is important to investigate the joint effects of these two stressors and provide data that could lead to more informed risk assessment. Here we describe how to set up a co-exposure to pesticides and ultraviolet B radiation to examine their joint toxicity in amphibian embryos and larvae, focusing on Xenopus laevis with notes on other amphibian species. With modifications, the methods may be applied to other types of chemicals or other aquatic organisms of interest.


Assuntos
Exposição Ambiental/efeitos adversos , Praguicidas/toxicidade , Raios Ultravioleta/efeitos adversos , Xenopus laevis/crescimento & desenvolvimento , Animais , Feminino , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/efeitos da radiação , Masculino , Testes de Toxicidade/métodos , Xenopus laevis/embriologia
16.
Methods Mol Biol ; 2326: 203-214, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34097270

RESUMO

Cyantraniliprole can effectively control lepidopteran pests and has been used all over the world. In general, the risk of cyantraniliprole seems low for fish, but the toxicity selectivity among different fish species was not clear. Here, we present the methods for the acute toxicity and chronic effects of cyantraniliprole by using juvenile tilapia (Oreochromis mossambicus). Based on this test, 96 h LC50 of cyantraniliprole to tilapia was 38.0 mg/L. After exposed for 28 days, specific growth rates of the blank control, solution control, and the treatments of 0.037, 0.37 and 3.7 mg/L of cyantraniliprole were 1.14, 0.95, 0.93, 0.82, and 0.70% per day, respectively. The results of micronucleus experiment and single cell gel electrophoresis showed that cyantraniliprole damaged DNA in liver cells of tilapia larvae. Quantitative PCR results showed that cyantraniliprole could induce the upregulation of Rpa 3 that is responsible for the DNA repair. The significant downregulation of Chk 2 gene was related to p53 pathway. It is therefore proposed that cyantraniliprole causes DNA damage in liver cells of tilapia and activates DNA damage and repair pathways.


Assuntos
Dano ao DNA/efeitos dos fármacos , Inseticidas/toxicidade , Pirazóis/toxicidade , Tilápia , Poluentes Químicos da Água/toxicidade , ortoaminobenzoatos/toxicidade , Animais , Larva/citologia , Larva/efeitos dos fármacos , Larva/genética , Larva/crescimento & desenvolvimento , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Testes para Micronúcleos/métodos , Análise de Célula Única/métodos , Tilápia/crescimento & desenvolvimento , Tilápia/metabolismo , Testes de Toxicidade/métodos
17.
Exp Parasitol ; 226-227: 108120, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34089701

RESUMO

The bio-efficacy of crude ethyl acetate extract, fractions and a compound phenyl acetic acid from the ethyl acetate extract of Streptomyces collinus was evaluated on Culex quinquefasciatus Say and Aedes aegypti L. mosquitoes (Diptera: Culicidae). The larvae were exposed to concentrations of 2.5, 5.0, 7.5 and 10.0 ppm for fractions and 0.5, 1.0, 1.5 and 2.0 ppm for compound. After 24 h, the larval mortality was assessed and the LC50 and LC90 values were calculated. Similarly, per cent ovicidal activity was calculated for eggs after 120 h post treatment for phenyl acetic acid. Among the eleven fractions screened, fraction 7 from the ethyl acetate extract of Streptomyces collinus exhibited good larvicidal activity against both mosquito species. The LC50 and LC90 values of fraction 7 were 4.42, 6.23 ppm against Cx. quinquefasciatus larvae and 5.13, 14.51 ppm against Ae. aegypti larvae, respectively. Further, the isolated compound, phenyl acetic acid from fraction 7 recorded 100% larvicidal activity at 2 ppm concentration with LC50 and LC90 values of 2.07, 4.87 ppm on Cx. quinquefasciatus larvae and 3.81, 9.87 ppm on Ae. aegypti larvae, respectively. Phenyl acetic acid presented 50.3% and 42.0% ovicidal activity against Cx. quinquefasciatus and Ae. aegypti eggs at 2 ppm concentration after 120 h post treatment. The compound, phenyl acetic acid could be used in mosquito control programme.


Assuntos
Aedes , Culex , Fenilacetatos , Streptomyces/química , Aedes/efeitos dos fármacos , Aedes/enzimologia , Aedes/crescimento & desenvolvimento , Análise de Variância , Animais , Bioensaio , Culex/efeitos dos fármacos , Culex/enzimologia , Culex/crescimento & desenvolvimento , Esterases/antagonistas & inibidores , Glutationa Transferase/antagonistas & inibidores , Índia , Larva/efeitos dos fármacos , Dose Letal Mediana , Óvulo/efeitos dos fármacos , Fenilacetatos/química , Fenilacetatos/isolamento & purificação , Fenilacetatos/farmacologia
18.
Int J Food Microbiol ; 352: 109281, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34126526

RESUMO

Food-borne pathogenic bacteria are dispersed throughout the entire chain of the food industry. However, many food preservatives are limited by poor biocompatibility such as cumulative poisoning. The antimicrobial peptide is increasingly regarded as a promising preservative in food research due to its high bioactivity and low cytotoxicity. In this study, thirteen peptides were designed, synthesized, and screened for application as food preservatives. One of them, termed zp65, whose sequence is GIOAOIIIOIOO-NH2, demonstrated potent bactericidal effect against common Gram-negative strains including enterohemorrhagic Escherichia coli, Salmonella, and Citrobacter freundii. Encouragingly, zp65 showed negligible cytotoxicity to both mammalian cells and Galleria mellonella larvae. Peptide zp65 was prone to form α-helix structure in amphiphilic environments, facilitating its affinity with bacterial membrane. Furthermore, the proteolytic stability of zp65 was much higher than its derivatives consisting of totally natural amino acids. Isothermal titration calorimetry indicated that zp65 has a strong binding affinity to lipopolysaccharide with Kd = 1.3 µM, suggesting its possible action target on the bacterial envelope. Mechanistic studies revealed that this peptide also influenced the membrane potential of E.coli O157:H7 (O157) in a dose-dependent manner. Surprisingly, peptide zp65 did not induce disruption of membrane permeability even at a higher concentration of 4-fold minimal inhibitory concentration. By employing confocal microscopy, peptide zp65 labeled by fluorescein isothiocyanate mainly aggregated on the bacterial membrane. These results suggested that the bactericidal mode of action of zp65 is likely attributed to depolarization of the cell membrane. The minced lean beef experiment indicated that the maximum reduction of O157 reached 1.46 log colony-forming unit (CFU) per gram on day 1 after zp65 treatment at the dosage of 40 µg/g. Compared with the untreated cooked beef sample, the CFU of the zp65-treated group remained at a much lower level after 10-day storage. Subsequently, treatment with zp65 at concentrations above 32 µM also significantly reduced O157 viable counts in fresh tomato juice. And the zp65 treatment could rescue about 40% of Galleria mellonella larvae injected with O157-contaminated tomato juice. The peptide zp65 exhibits great potential and deserves further study as a candidate for food preservative.


Assuntos
Escherichia coli O157/efeitos dos fármacos , Microbiologia de Alimentos , Conservantes de Alimentos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Proteínas Citotóxicas Formadoras de Poros/farmacologia , Animais , Antibacterianos/farmacologia , Bovinos , Contagem de Colônia Microbiana , Larva/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Mariposas/efeitos dos fármacos , Ornitina/química , Carne Vermelha/microbiologia
19.
Molecules ; 26(9)2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-34068691

RESUMO

Due to widespread multi-drug resistance in parasitic nematodes of livestock animals, there is an urgent need to discover new anthelmintics with distinct mechanisms of action. Extending previous work, here we screened a panel of 245 chemically-diverse small molecules for anti-parasitic activity against Haemonchus contortus-an economically important parasitic nematode of livestock. This panel was screened in vitro against exsheathed third-stage larvae (xL3) of H. contortus using an established phenotypic assay, and the potency of select compounds to inhibit larval motility and development assessed in dose-response assays. Of the 245 compounds screened, three-designated MPK18, MPK334 and YAK308-induced non-wildtype larval phenotypes and repeatedly inhibited xL3-motility, with IC50 values of 45.2 µM, 17.1 µM and 52.7 µM, respectively; two also inhibited larval development, with IC50 values of 12.3 µM (MPK334) and 6.5 µM (YAK308), and none of the three was toxic to human liver cells (HepG2). These findings suggest that these compounds deserve further evaluation as nematocidal candidates. Future work should focus on structure-activity relationship (SAR) studies of these chemical scaffolds, and assess the in vitro and in vivo efficacies and safety of optimised compounds against adults of H. contortus.


Assuntos
Haemonchus/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Haemonchus/crescimento & desenvolvimento , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Fenótipo , Bibliotecas de Moléculas Pequenas/química
20.
Int J Mol Sci ; 22(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065835

RESUMO

The discovery of eco-friendly, rapid, and cost-effective compounds to control diseases caused by microbes and insects are the main challenges. Herein, the magnesium oxide nanoparticles (MgO-NPs) are successfully fabricated by harnessing the metabolites secreted by Penicillium chrysogenum. The fabricated MgO-NPs were characterized using UV-Vis, XRD, TEM, DLS, EDX, FT-IR, and XPS analyses. Data showed the successful formation of crystallographic, spherical, well-dispersed MgO-NPs with sizes of 7-40 nm at a maximum wavelength of 250 nm. The EDX analysis confirms the presence of Mg and O ions as the main components with weight percentages of 13.62% and 7.76%, respectively. The activity of MgO-NPs as an antimicrobial agent was investigated against pathogens Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans, and exhibited zone of inhibitions of 12.0 ± 0.0, 12.7 ± 0.9, 23.3 ± 0.8, 17.7 ± 1.6, and 14.7 ± 0.6 mm respectively, at 200 µg mL-1. The activity is decreased by decreasing the MgO-NPs concentration. The biogenic MgO-NPs exhibit high efficacy against different larvae instar and pupa of Anopheles stephensi, with LC50 values of 12.5-15.5 ppm for I-IV larvae instar and 16.5 ppm for the pupa. Additionally, 5 mg/cm2 of MgO-NPs showed the highest protection percentages against adults of Anopheles stephensi, with values of 100% for 150 min and 67.6% ± 1.4% for 210 min.


Assuntos
Anopheles/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Inseticidas/farmacologia , Óxido de Magnésio/farmacologia , Penicillium chrysogenum/crescimento & desenvolvimento , Animais , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Bacillus subtilis/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Cristalografia por Raios X , Escherichia coli/efeitos dos fármacos , Química Verde , Inseticidas/química , Inseticidas/isolamento & purificação , Larva/efeitos dos fármacos , Óxido de Magnésio/química , Óxido de Magnésio/isolamento & purificação , Metabolômica , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Penicillium chrysogenum/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pupa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
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