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The TiO2/MCM-41 nanomaterials were synthesized by impregnation with an excess solvent with different percentages of titanium dioxide. They were used for catalytic degradation of Benzene Toluene Ethylbenzene and Xylenes (BTEX) in the presence of hydrogen peroxide in aqueous media. The obtained materials were characterized by X-ray Diffraction, nitrogen adsorption-desorption using the BET method and Fourier Transform Infrared Spectroscopy. The nanostructured phase of the hexagonal ordered materials was obtained even after modification with titanium oxide and calcination. The characterizations have proven the effectiveness of the synthesis method used to incorporate titanium with anatase structure impregnated in the nanoporous of the MCM-41 material. Anatase is the main active phase of TiO2 to oxidize organic compounds. The catalytic evaluation wascarried out in a semi-bath reactor with 20 mL of a mixture containing BTEX (100 mg/L), hydrogen peroxide (2.0 mol/L) and TiO2/MCM-41 (2.0 g/L) in aqueous media. The reactions were carried out at a temperature of 60°C for 5 hours, and the analyses were performed by gas chromatography with a photoionization detector and headspace sampler. The catalytic tests showed satisfactory results with more than 95% of conversion, where the catalyst 48%TiO2/MCM-41 presented higher performance.

Early detection of herbicide resistance in weeds is crucial for successful implementation of integrated weed management. We conducted a herbicide resistance survey of the winter annual grasses feral rye (Secale cereale), downy brome (Bromus tectorum), and jointed goatgrass (Aegilops cylindrica) from Colorado winter wheat production areas for resistance to imazamox and quizalofop.All samples were susceptible to quizalofop. All downy brome and jointed goatgrass samples were susceptible to imazamox. Out of 314 field collected samples, we identified three feral rye populations (named A, B, and C) that were imazamox resistant. Populations B and C had a target-site mechanism with mutations in the Ser653 residue of the acetolactate synthase (ALS) gene to Asn in B and to Thr in C. Both populations B and C had greatly reduced ALS in vitro enzyme inhibition by imazamox. ALS feral rye protein modeling showed that steric interactions induced by the amino acid substitutions at Ser653 impaired imazamox binding. Individuals from population A had no mutations in the ALS gene. The ALS enzyme from population A was equally sensitive to imazamox as to known susceptible feral rye populations. Imazamox was degraded two times faster in population A compared with a susceptible control. An oxidized imazamox metabolite formed faster in population A and this detoxification reaction was inhibited by malathion.Population A has a nontarget-site mechanism of enhanced imazamox metabolism that may be conferred by cytochrome P450 enzymes. This is the first report of both target-site and metabolism-based imazamox resistance in feral rye. © 2022 The Authors. Pest Management Science published by John WileySons Ltd on behalf of Society of Chemical Industry.

The purpose of this research was to synthesize nanocomposites formed by sulfur nanoparticles, coated with eucalyptus and rosemary essential oil. To determinate the insecticidal effect in the control of nymphs of paratrioza (Bactericera cockerelli Sulc) in potato crops. A solution of thiosulfate was reduced to zero valent sulfur, the sulfur nanoparticles were coated with eucalyptus and rosemary essential oil at three concentrations: 0.25%, 0.5% and 0.75%. The samples were characterized by UV-visible spectroscopy, energy dispersive spectroscopy, transmission electron microscopy and scanning electron microscopy. Insecticidal efficacy was evaluated at 24, 48 and 72 hours after application. Furthermore, efficacy was compared versus the commercial insecticide thiamethoxam 0.25% and a control. The results show that eucalyptus nanocomposites at concentrations: 0.25%, 0.5% and 0.75% and rosemary nanocomposites at concentration of 0.5%, have an insecticidal efficacy of 100% for the control of insect nymphs 24 hours after application. While the insecticidal efficacy of rosemary nanocomposites at concentrations of 0.25% and 0.75% increases over time, reaching 100% at 24 and 72 hours respectively. The synthesized nanocomposites are more effective in controlling nymphs of paratrioza than the commercial insecticide thiamethoxam. Could be used for the development of new insecticides.

Mesoporous Cu(Fe)/SBA-15 catalysts were prepared with distinct metal loadings of ca. 2–10 wt.%. A detailed set of characterizations using X-ray diffraction (XRD), electron paramagnetic resonance (EPR), transmission electron microscopy (TEM), scanning electron microscopy coupled to energy dispersive spectroscopy (SEM-EDS), Mössbauer spectroscopy, X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy was performed to correlate the relationship among structure, electronic properties and catalytic performances. All solids were evaluated in the selective catalytic reduction of NOx in the presence of CO (CO-SCR). The influence of the metal loadings on the overall activity indicated that introducing high amounts of Fe or Cu on the catalysts was beneficial to form either CuO or α-Fe2O3 clusters. Cux/SBA-15 series exhibited more efficient activity and poison-tolerant ability during CO-SCR reaction, in contrast to Fex/SBA-15. In spite of the Fe species introduced on SBA-15 having structural features similar to those of Cu ones, low interactions among Fe nanoparticles, silica and clusters impeded the high performances of Fe10/SBA-15. XPS revealed the Fe species in a more oxidized state, indicating the stability of the solid after the catalytic tests, in agreement with EPR and Raman spectroscopy. Cu8/SBA-15 worked better, being recyclable due to the interaction of the Cu2+ ions with SBA-15, avoiding the deactivation of the catalyst.

The preparation, characterization and application of materials based on montmorillonite natural clay containing aluminum polyhydroxocomplexes of Keggin type ions (Al13) as intercalating agent and h...

In this work, we evaluated the short time-induced oxidative stress–mediated rapid metabolic and physiological responses of resistant and susceptible Sumatran fleabane [Conyza sumatrensis (Retz.) E. Walker; syn.: Erigeron sumatrensis Retz.] to 2,4-D herbicide. Under fixed conditions (25 C and 65 ± 5% relative humidity), we assayed injury symptoms, chlorophyll a fluorescence, and antioxidative systems of biotypes both resistant and susceptible to 2,4-D (1,005 g ae ha−1). Under 15 versus 25 C temperatures and light and dark conditions, oxidative stress–mediated damage was assayed on plants that received 2,4-D herbicide applications. The injury symptoms observed in the 2,4-D–resistant biotype were rapid necrosis in leaves within 30 min, with the reestablishment of normal growth within 1 to 2 wk after 2,4-D treatment. The basal antioxidant enzyme activities of superoxide dismutase, catalase, and ascorbate peroxidase were greater in the resistant than in the susceptible biotype, although the activities of all enzymes generally did not differ between untreated and treated in the resistant biotype. The resistant biotype showed great reduction (at 1 and 4 h after application) in the photosynthetic electron transport chain performance index, while these metabolic changes were only detected after 4 h in the susceptible biotype. The resistant biotype recovered from the foliar damage 1 to 2 wk after 2,4-D application, while the susceptible biotype was controlled. The production of H2O2 was responsive to temperature and increased more rapidly in the 2,4-D–resistant biotype than in the susceptible one at both 15 and 25 C; however, there was a greater increase at 25 C in the resistant biotype. H2O2 production was not light dependent in 2,4-D–resistant C. sumatrensis, with increases even under dark conditions. The 2,4-D–resistant biotype showed rapid photosynthetic damage, possibly due to the rapid necrosis and leaf disruption, and increased H2O2 content compared with the susceptible biotype.

Introduction: Seed storage proteins provide a store of amino acids for use during germination and seedling growth but can also play a defensive role in their insecticidal and antimicrobial properties. We determined the potential toxic activity of a 2S albumin, isolated, from crambe seeds, on the growth of Trypanosoma cruzi,a protozoan that causes Chagas disease. Human Chagas disease is a tropical illness that affects 6-8 million people worldwide, causing approximately 8000 deaths in 2015. Methods: Crambe seed proteins were extracted in phosphate buffer and chromatographically partitioned. The fractions were submitted to a growth-inhibition assay against T. cruzi epimastigotes and amastigotes in LLC-MK2 host cells. The cells were examined by light and transmission electron microscopy. Results: The 2S albumin protein was not toxic to LLC-MK2 cells at 500 µg/mL but eliminated 70% of the epimastigotes after 48 h and reduced the number of amastigotes infected cells. Amastigotes are the protozoa form found in the bloodstream or within host cells. Morphological and ultrastructural analyses demonstrated the parasite's deformation and organelles, including membrane damage and fragmentation of intracellular amastigotes. Conclusions: 2S albumin from crambe exhibits activity against both amastigote and epimastigote T. cruzi forms and may be sources of new compounds clinically active against T. cruzi.

Helichrysum italicum essential oil (H. italicum EO) is recognized for its anti-inflammatory, antimicrobial and wound-healing properties. The main goal of the present work was the development and characterization of a gel formulation comprising H. italicum EO loaded in chitosan nanoparticles (NPs) for dermatological applications. H. italicum EO-loaded chitosan NPs presented hydrodynamic diameter and PdI of about 300 nm and 0.28, respectively, and a surface charge of +19 mV. The H. italicum EO-loaded chitosan NPs were prepared by means of ionic gelation and then incorporated into a thermal water gel formulation. The organoleptic and physicochemical properties of the developed gel were studied. The gel remained stable under accelerated test conditions, maintaining pH, viscosity and organoleptic properties. In addition, the formulation presented pH, viscosity and spreadability properties suitable for topical application. Finally, the performance of the gel in topical application was evaluated on the skin of volunteers using non-invasive methods, particularly, by means of biometric evaluation. These assays showed that the properties of the developed thermal water-based gel formulation with H. italicum EO-loaded chitosan NPs can improve skin hydration and maintain healthy skin conditions, demonstrating its putative role for distinct dermatological applications.

The 2030 Sustainable Development Goals of the United Nations include a strong emphasis on ending hunger worldwide. According to the 2019 Global Food Security Index, while 88% of countries claim there is sufficient food supply in their country, the sad reality is that 1 in 3 countries is facing insufficient availability of food supply, which means that in those countries, more than 10% of the population is malnourished. Since nutrition is crucial to leading a healthy life and satisfying food security needs, several governments have turned to national nutrition surveys to gauge the extent of malnutrition in their populations. Plants are able to grow, develop, and store nutrients by photosynthesis, which convert light into chemical energy through cell redox regulatory networks. A photosynthesis system's electron flow may be adjusted to accommodate varying light and environmental circumstances. Many techniques exist for controlling the flow of electrons emitted during light processes in order to save or waste energy. The two protein molecules TROL and flavoenzyme ferredoxin (oxidoreductase+NADP) (FNR) interact dynamically to form an excellent molecular switch capable of splitting electrons from the photosystem. The TROL-FNR bifurcation may be limited by either generating NADPH or preventing reactive oxygen species from propagating. TROL-based genome editing is an experimental method for enhancing plant stress and defensive responses, efficiency, and ultimately agricultural production. Resumo Os Objetivos de Desenvolvimento Sustentável de 2030 da Organização das Nações Unidas incluem uma forte ênfase em acabar com a fome em todo o mundo. De acordo com o Índice Global de Segurança Alimentar de 2019, enquanto 88% dos países afirmam que há abastecimento alimentar suficiente em seu país, a triste realidade é que 1 em cada 3 países enfrenta disponibilidade insuficiente de alimentos, o que significa que, nesses países, mais de 10% da população está desnutrida. Uma vez que a nutrição é crucial para levar uma vida saudável e satisfazer as necessidades de segurança alimentar, vários governos recorreram a pesquisas nacionais de nutrição para avaliar a extensão da desnutrição em suas populações. As plantas são capazes de crescer, desenvolver e armazenar nutrientes pela fotossíntese, que converte luz em energia química por meio de redes reguladoras redox celulares. O fluxo de elétrons de um sistema de fotossíntese pode ser ajustado para acomodar luz variável e circunstâncias ambientais. Existem muitas técnicas para controlar o fluxo de elétrons emitidos durante os processos de luz, a fim de economizar ou desperdiçar energia. As duas moléculas de proteína TROL e a flavoenzima ferredoxina (oxidorredutase+NADP) (FNR) interagem dinamicamente para formar um excelente interruptor molecular capaz de separar elétrons do fotossistema. A bifurcação TROL-FNR pode ser limitada, gerando NADPH ou impedindo a propagação de espécies reativas de oxigênio. A edição do genoma baseada em TROL é um método experimental para aumentar o estresse da planta, as respostas defensivas, a eficiência e, finalmente, a produção agrícola.