Herbicide and Cytogenotoxic Activity of Inclusion Complexes of Psidium gaudichaudianum Leaf Essential Oil and ß-Caryophyllene on 2-Hydroxypropyl-ß-cyclodextrin.

The present investigation aimed to develop inclusion complexes (ICs) from Psidium gaudichaudianum (GAU) essential oil (EO) and its major compound ß-caryophyllene (ß-CAR), and to evaluate their herbicidal (against Lolium multiflorum and Bidens pilosa) and cytogenotoxic (on Lactuca sativa) activities. The ICs were obtained using 2-hydroxypropyl-ß-cyclodextrin (HPßCD) and they were prepared to avoid or reduce the volatility and degradation of GAU EO and ß-CAR. The ICs obtained showed a complexation efficiency of 91.5 and 83.9% for GAU EO and ß-CAR, respectively. The IC of GAU EO at a concentration of 3000 µg mL-1 displayed a significant effect against weed species B. pilosa and L. multiflorum. However, the ß-CAR IC at a concentration of 3000 µg mL-1 was effective only on L. multiflorum. In addition, the cytogenotoxic activity evaluation revealed that there was a reduction in the mitotic index and an increase in chromosomal abnormalities. The produced ICs were able to protect the EO and ß-CAR from volatility and degradation, with a high thermal stability, and they also enabled the solubilization of the EO and ß-CAR in water without the addition of an organic solvent. Therefore, it is possible to indicate the obtained products as potential candidates for commercial exploration since the ICs allow the complexed EO to exhibit a more stable chemical constitution than pure EO under storage conditions.

Green synthesis of Fe0 nanoparticles using Eucalyptus grandis leaf extract: Characterization and application for dye degradation by a (Photo)Fenton-like process.

Zero-valent iron nanoparticles (EGnZVI) were synthesized using Eucalyptus grandis (EG) leaf extract as a reducing/stabilizing agent. The studied materials (EG leaves, extract and EGnZVI) were characterized using the XRD, FTIR, Raman spectroscopy, SEM, TEM/EDS techniques. The results indicate that several organic compounds, including phenolics, present in the EG leaves were successfully extracted and incorporated into the structure of the material, possibly promoting the capping and stabilization of the formed zero-valent iron particles. The EGnZVI presented low crystallinity, varied size (50-500 nm), approximately spherical shape, and formed aggregates. The EGnZVI were utilized in the removal of the Direct Red 80 (DR80), an azo dye. The effects of the temperature (15-35 °C), initial DR80 concentration (10-250 mg L-1), initial pH (2.5-8.5), the doses of H2O2 (0.5-5 mmol L-1) and EGnZVI (0.2-10 mg L-1), and the incidence of UV-light were evaluated. The EGnZVI did not present reactivity towards the DR80 in the absence of H2O2. However, in the presence of H2O2, the EGnZVI was highly efficient at removing the DR80 at slightly acidic pH0 values (4 and 5.5). Under these pH0 conditions, the EGnZVI/Fenton process proved to be more effective than the classic homogenous Fenton. Finally, in the presence of the UV-light, the process was highly efficient throughout the studied pH0 interval, with increased removal rates. Therefore, the nZVI/Fenton process, using the synthesized material, presents itself as a promising alternative for the degradation of organic pollutants, and the incidence of UV light can considerably improve its efficiency.

Triazole-functionalized hydrochar-stabilized Pd nanocatalyst for ullmann coupling.

Biomass valorization is essential, particularly in emerging countries. Here, hydrochar from arabica coffee straw was functionalized with a triazole group (HD-TRz) for use as a support of palladium nanoparticles (PdNPs-HD-TRz) applied in the Ullmann coupling reaction for the first time. It provided remarkably excellent selectivities, conversions at a temperature as low as 45 °C and catalyst recyclability, surpassing previous literature performances. Hydrochar was obtained by one-pot reaction via hydrothermal synthesis, using NaOH solution as activating agent and functionalized with a 1,3-triazole group by CuAAC "click" reaction. The PdNPs were prepared via reduction of hydrochar-bound Pd(II) using NaBH4. Hydrochar functionalization was monitored by infrared spectroscopy, and X-ray diffraction (XRD) allowed to observe carbon and palladium planes in hydrochar and PdNPs HD-TRz structures. The PdNPs presented a spherical shape with 2.1 ± 0.1 nm size, homogeneously distributed in the carbon coverslips. The HD-TRz-supported PdNPs were used as a catalyst in the Ullmann reaction of iodobenzene, using ethanol as solvent with 100% of conversion and 91% selectivity at 45 °C. The material was reused, presenting 100% of conversion and selectivities of 92, 84 and 73% for the 1st, 2nd and 3rd cycle, respectively. The scope of the reaction was expanded to other molecules showing the potential of this and other triazole-hydrochar-supported nanocatalysts.

Reuse of iron ore tailings as an efficient adsorbent to remove dyes from aqueous solution.

In this work, an iron ore tailings sample (IOT), collected from a tailings dam in Minas Gerais, Brazil, was characterized. The IOT presented point of zero charge of ∼ 6, specific surface area of 4 m2 g-1, and was mainly composed of hematite and quartz. Subsequently, experiments were performed to evaluate the adsorption of an anionic dye, Direct Red 80 (DR80), and a cationic dye, Methylene Blue (MB), by the IOT, studying the effects of its dose (doseIOT) and the solution initial pH (pH0). The DR80 removal increased with the decrease of the pH0 while the opposite effect occurred in the experiments with the MB, suggesting the process is governed by the adsorption resulting from electrostatic forces. The increase in the doseIOT increased the DR80 and MB removal, which can be attributed to the greater availability of adsorption sites. Pseudo-second order kinetic (R2 > 0.9994) and the Langmuir equilibrium isotherm (R2 > 0.9842) models described well the DR80 adsorption by the IOT, being the reaction rate and maximum adsorption capacity higher at lower pH0. In a regeneration experiment, it was possible to desorb almost entirely the DR80 using a NaOH solution. Additionally, the regenerated IOT was able to adsorb the DR80, demonstrating its reusability. In a preliminary assay, the IOT decreased the colour of the textile wastewater sample at pH0 3. Therefore, the results indicate the potential use of IOT for removing electric-charged pollutants by adsorption, especially anionic ones under acidic conditions.

Cr(VI) reduction and adsorption by bimetallic nanoparticles from Li-ion batteries.

In this work, bimetallic nanoparticles of cobalt and copper (NPLIB) were synthetized from obsolete Li-ion batteries cellphones and applied for the first time in the Cr(VI) removal. NPLIB has approximately 50 and 40% of Co and Cu content, respectively. The material is composed of Cu0 and Co0 but also presents metal oxides on its surface. The nanoparticles have spherical morphology and a high agglomeration capacity. The cobalt was better distributed on the surface, while copper was present in small scattered clusters. The NPLIB have an average diameter of 13.5 nm being confirmed the formation of the core-shell structure. The point of zero charge was calculated as 8.3. The NPLIB were used in the Cr(VI) removal process in aqueous solution, exhibiting a removal efficiency of ≈ 90% in 60 min of reaction. The kinetics study showed a mechanism consisting of two phases and better fit by pseudo-second-order model. The first phase is faster than the second. It is possible to observe peaks related to the oxidation of Co and Cu in the post reaction NPLIB by X-ray diffraction analysis, suggesting the modification of the material. Raman spectroscopy has shown that Cr(VI) is reduced to Cr(III) and remains bound to the surface of the nanoparticle, even after the desorption process, reducing its removal efficiency in new cycles. Graphical abstract.

Environmental remediation processes by zero valence copper: reaction mechanisms.

Recent studies have shown Cu(0) as a promising material for the removal of organic and inorganic pollutants. However, there is no review addressing the studies performed. This fact may be related to the toxicity of the particles and the copper released in solution that has not motivated researchers, which entails in a reduced number of publications. However, studies point out how to solve the problem of Cu deposition in support materials. In this work, a detailed review of Cu(0) applications was performed. The specific focus was the reaction mechanisms related to adsorption, oxidation, and reduction processes. Initially, the resources that allow the understanding of the reaction mechanism, such as characterization techniques and the experimental conditions for investigation of the species involved in the process, were presented. The studies were evaluated separately, showing the mechanisms involved only with the application of Cu(0) in pure and isolated form and in association with oxidizing or reductive agents, combined with irradiation sources and ultrasonic waves and in the form supported in polymer matrices. It was verified that by the proposed reaction mechanisms, the exclusive participation of Cu(0), being the removal process, explained only by the redox behavior of copper. Therefore, the review showed the need for future research regarding the redox behavior of the contaminants.

Study of Cu NPs reactivity for compounds with different chemical structures: Black reactive dye 5, picric acid and 2,4-D herbicide.

In this study, the copper nanoparticles (Cu NPs) reactivity for degradation of the reactive dye black 5 (RP5), picric acid (PA) and 2,4-D herbicide was evaluated. The RP5 degradation occurred by oxidative via, through hydroxyl radicals generated in situ, with active participation of Cu(I) and H2O2. The use of catalase confirmed the hydrogen peroxide formation in situ. Reduction degradation via electron transfer was also possible. On the other hand, PA had low degradation efficiency (less than 20%) under any conditions studied (similar to those used for RP5). High degradation efficiency for 2,4-D was achieved by the association of the Cu NPs/H2O2. Thus, the behavioral model of Cu NPs has been proven. This behavioral difference of the chemical species to be degraded in relation to the behavior of the Cu NPs was studied, evaluating its redox behavior by voltammetric analyzes. This study aided in the understanding and selection of the chemical species that can be degraded by these NPs.

Characterization and evaluation of sorption potential of the iron mine waste after Samarco dam disaster in Doce River basin - Brazil.

The Fundão dam collapsed releasing 60 million tons of mining waste into the environment. The mining wastes should be better studied, since some of them are deposited on the alluvial plains soil and at the bottom of the rivers, like sediments, of the region affected. Thus, this work aims to perform the chemical, physical and adsorptive characterization of the samples colleted in region de Paracatu de Baixo. The mining waste has uneven surface, with sizes ranging from 2 to 200 µm, pHPCZ in 6.0. Are composed predominantly by kaolinite, goethite, hematite, gibbsite and quartz. It has been classified as non-hazardous residues. The adsorption studies showed the mining waste have a low Cationic Exchange Capacity. The sorption process was occurs by ion exchange and the kinetics follows the pseudo second order model (R2 > 0.78). The process is endothermic (ΔH in 29.33 kJ mol-1) and spontaneous (ΔG in -24.7 kJ mol-1 at 25 °C). The Langmuir model presented a better fit (R2 > 0.995) to the experimental data. Therefore, the methylene blue can be used as a cation model to predict the behavior of cationic species on the mining waste, with maximum adsorption capacity of 4.42 mg g-1 at 25 °C.

Development and validation of a multiclass method for the determination of veterinary drug residues in chicken by ultra high performance liquid chromatography-tandem mass spectrometry.

A multiclass method has been optimized and validated for the simultaneous determination of 20 veterinary drug residues belonging to several classes, as quinolones, sulfonamides, macrolides, anthelmintics, avermectins and diamino derivatives, and benzathine, used as a marker of the presence of penicillin, in muscle chicken. It has been based on QuEChERS methodology (quick, easy, cheap, effective, rugged and safe) and ultra high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC-MS/MS). Several chromatographic conditions were optimized, obtaining a running time <8.5 min. The developed method was validated on the basis of international guidelines. Mean recoveries ranged from 70 to 120%, except for benzathine (65.6% at 20 µg kg(-1)) and sulfadimidine (69.0% at 100 µg kg(-1)). Repeatability was lower than 20.0% except for sulfachlorpyridazine (22.1% at 20 µg kg(-1)) and tylosin (20.5% and 20.6% at 30 and 50 µg kg(-1), respectively), whereas reproducibility was lower than 25% except for flumequine (27.4% at 20 µg kg(-1)) and benzathine (37.8% and 27% at 20 and 50 µg kg(-1), respectively). Limits of detection (LODs) and quantification (LOQs) ranged from 3.0 to 6.0 µg kg(-1) and 10.0 to 20.0 µg kg(-1), respectively, except for tylosin that showed a LOD and LOQ of 9.0 and 30.0 µg kg(-1). Decision limit (CC(α)) and detection capability (CC(ß)) were calculated and CC(ß) ranged from 24.1 µg kg(-1) (mebendazole) to 423.6 µg kg(-1) (flumequine). Finally, the method was applied to real samples and traces of some compounds were found in eight samples of chicken and benzathine was detected in one sample at 29.9 µg kg(-1).

Multiresidue determination of veterinary drugs in aquaculture fish samples by ultra high performance liquid chromatography coupled to tandem mass spectrometry.

A simple, selective and fast multiresidue method was developed for the determination of 32 veterinary drug residues belonging to several families, in gilthead sea bream (Sparus aurata) by ultra high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). The extraction was based on modified QuEChERS (quick, easy, cheap, effective, rugged and safe) procedure, using as extraction solution a mixture of acetonitrile and methanol (75:25, v/v), and it reduces sample handling, increasing sample throughput in relation to current methodologies. The developed method was validated and mean recovery ranged from 69% to 125% (at 10, 25, 50 and 100 µg/kg). Intra and interday precision, estimated as the same levels and expressed as relative standard deviation, RSD, were lower than 20% and 30%, respectively. Limits of detection (LODs) and quantification (LOQs) were lower than 7.5 and 25 µg/kg, respectively, except for danofloxacin, oxytetracycline and tetracycline (LOD and LOQ of 15.0 and 50 µg/kg, respectively). Decision limit (CC(α)) and detection capability (CC(ß)) were also calculated and ranged from 16.7 µg/kg (levamisole) to 605.0 (flumequine) µg/kg and from 23.5 µg/kg (levamisole) to 611.5 µg/kg (flumequine), respectively. The expanded uncertainty, U, was also evaluated ant it was below 25% at 100 µg/kg level, except for tetracycline (28%). Finally, the method was applied to ten samples obtained from local supermarkets in Almería (Spain) and traces of some compounds were detected.

Development and validation (according to the 2002/657/EC regulation) of a method to quantify sulfonamides in porcine liver by fast partition at very low temperature and LC-MS/MS.

A novel multi-residue method for the quantification of 15 sulfonamides in porcine liver is described. It involves the application of a liquid-liquid extraction with fast partition at very low temperature (LLE-FPVLT) procedure followed by HPLC-MS/MS (high performance liquid chromatography coupled to tandem mass spectrometry) analysis. By this innovative method, acetonitrile is added to a minced porcine liver sample and the resulting suspension centrifuged and immersed in a container with liquid nitrogen for 15 s. The acetonitrile phase, which remains liquid under these conditions, is isolated, evaporated to dryness, recomposed with formic acid 0.1% v/v, and injected into the liquid chromatograph. The whole analytical procedure was validated according to the European Commission Decision 2002/657/EC and acceptable values (except for sulfanilamide) were obtained for the following parameters: linearity (0.97 < R2 < 0.99), decision limit (107.70 µg kg-1 < CCα < 128.65 µg kg-1), detection capability (115.40 µg kg-1 < CCß < 157.29 µg kg-1), limit of detection (5.58 µg kg-1 < LOD < 16.75 µg kg-1), limit of quantification (18.41 µg kg-1 < LOQ < 55.26 µg kg-1), accuracy (recovery rates), precision (repeatability, intermediate precision, and measurement uncertainty tests), selectivity, and robustness. Recoveries higher than 70%, at three concentration levels (0.5, 1.0 and 1.5 of the maximum residue limit, MRL), were attained for the majority of the sulfonamides. These very promising results point to the inclusion of the present methodology into the National Residue Control Plan scope of the Ministry of Agriculture, Livestock and Food Supply of Brazil.

O idoso e a úlcera por pressão em serviço de atendimento domiciliar / Elderly people and ulcer caused by pressure at home care service

Esta pesquisa teve por objetivo estimar a prevalência de úlcera por pressão num serviço de atendimento domiciliar. Estudo transversal realizado em julho/agosto de 2009, com 194 idosos acamados. Para coleta dos dados, aplicou-se a Escala de Braden e um instrumento composto por dados sociodemográficos, clínicos e medidas preventivas para úlcera por pressão. Os dados foram analisados pelo programa SPSS 16.0 e apresentados em estatística descritiva. Do total, 69,6% (n = 135) eram mulheres; 68% (n = 132) ≥ 80 anos; 33% (n = 64) tinham Alzheimer e 26,3% (n = 51) sequela de acidente vascular encefálico; 31,4% (n = 61) apresentavam úlcera por pressão, sendo 54,1% (n = 33) hospitalar. Identificou-se prevalência de 31,4% e risco moderado (13,2) para úlcera por pressão. Recomenda-se estudo longitudinal para avaliar a relação dos indicadores da Escala de Braden com o desenvolvimento das úlceras por pressão.