Microwave and ultrasound extraction of antioxidant phenolic compounds from Lantana camara Linn. leaves: Optimization, comparative study, and FT-Orbitrap MS analysis.

INTRODUCTION: The species Lantana camara is used in folk medicine. The biological activities of this medicinal plant are attributable to the presence of various derivatives of triterpenoids and phenolic compounds present in its preparations, indicating excellent economic potential. OBJECTIVE: In this study, the operational conditions of ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) were optimized using Box-Behnken design to improve the total phenolic content (TPC) recovered in hydroethanolic extracts of L. camara leaves. MATERIAL AND METHODS: The TPC, total flavonoid content (TFC), and antioxidant activities of the hydroalcoholic extracts of L. camara, prepared by UAE and MAE under the optimized extraction conditions, were compared with those of the extracts obtained by conventional extraction methods. RESULTS: Under the optimal conditions, the extracts obtained by UAE (35% ethanol, 25 min, and a solvent-to-solid ratio of 60:1 mL/g) and by MAE (53% ethanol, 15 min, and 300 W) provided high yields of 32.50% and 38.61% and TPC values of 102.89 and 109.83 mg GAE/g DW, respectively. The MAE extract showed the best results with respect to TPC, TFC, and antioxidant activities, followed by extracts obtained by UAE, Soxhlet extraction, decoction, maceration, and infusion, in that order. CONCLUSION: The results obtained indicate that L. camara may be used as an important source of antioxidant phenolic compounds to obtain products with high biological and economic potential, especially when the extraction process is performed under appropriate conditions using MAE and/or UAE, employing environmentally friendly solvents such as water and ethanol.

Assessment of the effect of short-term weathering on the molecular-level chemical composition of crude oils in contact with aquatic environments.

Multiple studies have focused on the effect of long-term weathering processes on oils after spill events, without considering the chemical compositional changes occurring shortly after the release of oil into the environment. Therefore, the present study provides a broad chemical characterization for understanding of the changes occurring in the chemical compositions of intermediate (°API = 27.0) and heavy (°API = 20.9) oils from the Sergipe-Alagoas basin submitted to two simulated situations, one under marine conditions and the other in a riverine environment. Samples of the oils were collected during the first 72 h of contact with the simulated environments, followed by evaluation of their chemical compositions. SARA fractionation was used to isolate the resins, which were characterized at the molecular level by UHRMS. The evaporation process was highlighted, with the GC-FID chromatographic profiles showing the disappearance of compounds from n-C10 until n-C16, as well as changes in the weathering indexes and pristane + n-C17/phytane + n-C18 ratios for the crude oils submitted to the riverine conditions. Analysis of the resins fraction showed that basic polar compounds underwent little or no alterations during the early stages of weathering. The marine environment was shown to be much less oxidative than the riverine environment. For both environments, a feature highlighted was an increase of acidic oxygenated compounds with the increase of weathering, especially for the crude oil with °API = 27.0.

Chemical evaluation of pyrolysis oils from domestic and industrial effluent treatment station sludges with perspective to produce value-added products.

The use of renewable sources for energy has increased due to the high demand of modern society and the environmental impacts caused by the use of fossil fuels. Environmentally friendly renewable energy production may involve thermal processes, including the application of biomass. We provide a comprehensive chemical characterization of sludges from domestic and industrial effluent treatment stations, as well as the bio-oils produced by fast pyrolysis. A comparative study of the sludges and the corresponding pyrolysis oils was performed, with characterization of the raw materials using thermogravimetric analysis, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, elemental analysis, and inductively coupled plasma optical emission spectrometry. The bio-oils were characterized using comprehensive two-dimensional gas chromatography/mass spectrometry that identified compounds classified according to their chemical class, mainly related to nitrogenous (62.2%) and ester (18.9%) for domestic sludge bio-oil, and nitrogenous (61.0%) and ester (27.6%) for industrial sludge bio-oil. The Fourier transform ion cyclotron resonance mass spectrometry revealed a broad distribution of classes with oxygen and/or sulfur (N2O2S, O2, and S2 classes). Nitrogenous compounds (N, N2, N3, and NxOxclasses) were also found to be abundant in both bio-oils, due to the origins of the sludges (with the presence of proteins), making these bio-oils unsuitable for use as renewable fuels, since NOxgases could be released during combustion processes. The presence of functionalized alkyl chains indicated the potential of the bio-oils as sources of high added-value compounds that could be obtained by recovery processes and used for the manufacture of fertilizers, surfactants, and nitrogen solvents.

Assessment of black liquor hydrothermal treatment under sub- and supercritical conditions: Products distribution and economic perspectives.

This study reports an alternative method for black liquor treatment with potential for energy and process savings in the paper and pulp industry. Gasification of black liquor was carried out under sub- and supercritical conditions, varying the black liquor feed composition (0.10, 2.55 and 5.00 wb%) and temperature (350, 425 and 500 °C). Liquid products were identified by high resolution mass spectrometry (FT-Orbitrap MS) and compounds belonging to classes O3 and O4 were found to be the most representative in the products of reactions performed at 500 °C. The mass spectra results also revealed the overall selectivity of reactions, where decarboxylation and demethoxylation reactions were favored under subcritical and supercritical conditions, respectively. Among the gaseous products, hydrogen and methane were produced with maximum of 69.04 and 28.75 mol%, respectively, at 2.55 wb% and 425 °C. The proposed thermodynamic modelling of the reaction system satisfactorily predicted the gas phase behavior of the system. In the economic analysis, the simulated conditions indicated that the main energy requirements for a scaled-up black liquor gasification process are related to the necessary heat exchangers and pressurizing of the black liquor solution. Furthermore, the cost of the black liquor gasification is around 0.06 US$ per kg of feed stream. Liquid and gaseous products from gasification could be obtained at a cost of 56.64 US$ and 3.35 US$ per tonne of stream, respectively. Therefore, black liquor gasification is an interesting route for obtaining combustible gases and value-added bioproducts.

Selective carbonaceous-based (nano)composite sensors for electrochemical determination of paraquat in food samples.

A novel electrochemical sensor based on activated biochar (AB4) and reduced graphene oxide (rGO) was developed and tested for detection of paraquat (PQ) in food samples. Precursor biochar was obtained by the pyrolysis of water hyacinth biomass at 400, 500, and 600 °C, followed by a chemical activation step using HNO3 to increase the amount of oxygenated and nitrogenated groups. The modified electrodes (rGO-AB4) were tested in different experimental conditions, and exhibited good response under the optimized conditions, showing linearity from 0.74 to 9.82 µmol L-1 and a limit of detection and limit of quantification of 0.02 µmolL-1 and 0.07 µmol L-1, respectively. Interfering species such as glyphosate caused insignificant changes in the peak current of paraquat, and the selectivity of the method was tested using blank and spiked samples of coconut water, wastewater, honey, lettuce and lemon. Recovery ranged from 87.70±2.07% to 103.80±3.94%.

Comprehensive approach of methods for microstructural analysis and analytical tools in lignocellulosic biomass assessment - A review.

The trend in the modern world is to replace fossil fuels with green energy sources in order to reduce their environmental impact. The biorefinery industry, within this premise, needs to establish quantitative and qualitative analytical methods to better understand lignocellulosic biomass composition and structure. This paper presents chemical techniques (chromatography, thermal analysis, HRMS, FTIR, NIR, and NMR) and physicochemical techniques (XRD, optical and electron microscopy techniques - Confocal fluorescence, Raman, SPM, AFM, SEM, and TEM) for the microstructural characterization of lignocellulosic biomass and its derivatives. Each of these tools provides different and complementary information regarding molecular and microstructural composition of lignocellulosic biomass. Understanding these properties is essential for the design and operation of associated biomass conversion processing facilities. PAT, monitored in real-time, ensures an economical and balanced mass-energy process. This review aimed to help researchers select the most suitable analytical technique with which to investigate biomass feedstocks with recalcitrant natures.

Multiple reaction monitoring tool applied in the geochemical investigation of a mysterious oil spill in northeast Brazil.

In 2019, much of the northeastern coast of Brazil was impacted by a mysterious oil spill that caused an environmental disaster affecting 1009 beaches. Four samples were collected in the beaches between Sergipe and Pernambuco for geochemical characterization of the spilled oil and to compare with those main produced in Sergipe-Alagoas basin. Our approach in this evaluation was the use of a highly selective technique of sequential mass spectrometry by multiple reaction monitoring, to obtain the diagnostic ratios of hopanes and steranes biomarkers. Using these biomarkers ratios associated with multivariate statistical analysis, we found direct correlation between the spilled oil collected along the northeastern coast and no relationship between Sergipe-Alagoas basin crude oils was found. Furthermore, reported data for oils from Orinoco belt in Venezuelan basins were used for qualitative evaluation considering the indicative aspects suggested by the literature. Presence of highly specific biomarker 18α(H)-oleanane, and five other important diagnostic ratios evidenced correlation between the spilled oil and Naricual formation crude oils. Besides, due to the oleanane index, Ayacucho's crude oil presented the strongest factor of correlation with the spilled oil found on the northeast coast of Brazil.

Renewable Hydrocarbon Production from Waste Cottonseed Oil Pyrolysis and Catalytic Upgrading of Vapors with Mo-Co and Mo-Ni Catalysts Supported on γ-Al2O3.

In this work, the production of renewable hydrocarbons was explored by the means of waste cottonseed oil (WCSO) micropyrolysis at 500 °C. Catalytic upgrading of the pyrolysis vapors was studied using α-Al2O3, γ-Al2O3, Mo-Co/γ-Al2O3, and Mo-Ni/γ-Al2O3 catalysts. The oxygen removal efficiency was much lower in non-catalytic pyrolysis (18.0%), whilst γ-Al2O3 yielded a very high oxygen removal efficiency (91.8%), similar to that obtained with Mo-Co/γ-Al2O3 (92.8%) and higher than that attained with Mo-Ni/γ-Al2O3 (82.0%). Higher conversion yields into total renewable hydrocarbons were obtained with Mo-Co/γ-Al2O3 (61.9 wt.%) in comparison to Mo-Ni/γ-Al2O3 (46.6%). GC/MS analyses showed a relative chemical composition of 31.3, 86.4, and 92.6% of total renewable hydrocarbons and 58.7, 7.2, and 4.2% of oxygenated compounds for non-catalytic bio-oil (BOWCSO), BOMoNi and BOMoCo, respectively. The renewable hydrocarbons that were derived from BOMoNi and BOMoCo were mainly composed by olefins (35.3 and 33.4%), aromatics (31.4 and 28.9%), and paraffins (13.8 and 25.7%). The results revealed the catalysts' effectiveness in FFA decarbonylation and decarboxylation, as evidenced by significant changes in the van Krevelen space, with the lowest O/C ratio values for BOMoCo and BOMoNi (O/C = 0-0.10) in relation to the BOWCSO (O/C = 0.10-0.20), and by a decrease in the presence of oxygenated compounds in the catalytic bio-oils.

Magnetic nanostructured material as heterogeneous catalyst for degradation of AB210 dye in tannery wastewater by electro-Fenton process.

Degradation of the Acid Black 210 dye (AB210) in synthetic and industrial effluent samples was performed, for the first time, using a heterogeneous electro-Fenton (EF) process with a CoFe2O4/NOM magnetic hybrid catalyst (Hb200). The technique was compared with electrochemical oxidation using electrogenerated hydrogen peroxide (AO-H2O2). The catalyst was synthesized by the sol-gel technique, using water with a high content of natural organic matter (NOM) as an eco-friendly solvent. Analyses using XRD, FTIR, and TEM showed the formation of hybrid nanostructures with average size of 4.85 nm. Electrochemical assays were performed with a GDE/BDD electrode pair, electrogenerated H2O2, and current density of 45.4 mA cm-2. For the synthetic solution of AB210 at pH 3, the EF process presented higher efficiency, compared to AO-H2O2, with the optimum condition achieved using a lower mass of the catalyst (30 mg) and a higher concentration of the dye (55 mg L-1). The EF method also showed superior performance in the treatment of an industrial effluent with high organic load, at pH 6, with almost complete mineralization of AB210 (95%) in 7 h, while the AO-H2O2 process achieved 82% mineralization. The Hb200 hybrid maintained excellent catalytic activity during reuse in 3 cycles, with only 10% lower mineralization efficiency in the last cycle. GC-MS analysis showed that most of the contaminants in the effluent, including bis(2-ethylhexyl) phthalate, one of the most toxic, were eliminated or transformed after the EF treatment with Hb200.

Heterogeneous electro-Fenton process for degradation of bisphenol A using a new graphene/cobalt ferrite hybrid catalyst.

A simple, efficient, environmentally friendly, and inexpensive synthesis route was developed to obtain a magnetic nano-hybrid (GH) based on graphene and cobalt ferrite. Water with a high content of natural organic matter (NOM) was used as solvent and a source of carbon. The presence of NOM in the composition of GH was confirmed by FTIR and Raman spectroscopy, which evidenced the formation of graphene, as also corroborated by XRD analyses. The diffractograms and TEM images showed the formation of a hybrid nanomaterial composed of graphene and cobalt ferrite, with crystallite and particle sizes of 0.83 and 4.0 nm, respectively. The heterogeneous electro-Fenton process (EF-GH) achieved 100% degradation of bisphenol A (BPA) in 50 min, with 80% mineralization in 7 h, at pH 7, using a current density of 33.3 mA cm-2. The high catalytic performance was achieved at neutral pH, enabling substantial reduction of the costs of treatment processes. This work contributes to understanding the role of NOM in the synthesis of a magnetic nano-hybrid based on graphene and cobalt ferrite, for use in heterogeneous catalysis. This nano-hybrid has excellent potential for application in the degradation of persistent organic pollutants found in aquatic environments.

Molecular behavior assessment on initial stages of oil spill in terrestrial environments.

The contamination of terrestrial environments by oil spills creates biological risks to humans and affects the ecosystem's health. The studies that aim to evaluate the toxicity and changes in the environments are a field of potential interest to the scientific community. The objective of this study was to evaluate the changes in the chemical composition of crude oil fractions after the simulation of a spill in soil and sand, with emphasis on an immediate temporal investigation. Samples of intermediate (°API = 27.0) and heavy (°API = 20.9) oils from Sergipe-Alagoas basin were used. The evaporation process in the soil was highlighted; while the GC-FID chromatographic profiles demonstrated (1) the disappearance from n-C12 until n-C14 compounds, besides a decrease of more than 50% in n-C15 and n-C16 n-alkanes and (2) no changes in n-C17/Pr and n-C18/Ph ratios for both oils. Analysis of resins fraction performed by Orbitrap-MS has shown changes in the mass spectra profile and compound distribution during the soil and sand exposure process, with N1, O1, and O2 species showing changes in the relative abundance in ESI(+) mode, and O2, N1, and O1 for ESI(-). Changes in polar compounds of oil will depend on the extent of the time of interaction with soil and sand, taking into account intrinsic aspects, such as the nature of the soil and components in it as the organic matter.

Streptomyces hygroscopicus UFPEDA 3370: A valuable source of the potent cytotoxic agent nigericin and its evaluation against human colorectal cancer cells.

Streptomyces hygroscopicus UFPEDA 3370 was fermented in submerged cultivation and the biomass extract was partitioned, obtaining a fraction purified named EB1. After purification of EB1 fraction, nigericin free acid was obtained and identified. Nigericin presented cytotoxic activity against several cancer cell lines, being most active against HL-60 (human leukemia) and HCT-116 (human colon carcinoma) cell lines, presenting IC50 and (IS) values: 0.0014 µM, (30.0) and 0.0138 µM (3.0), respectively. On HCT-116, nigericin caused apoptosis and autophagy. In this study, nigericin was also screened both in vitro and in silico against a panel of cancer-related kinases. Nigericin was able to inhibit both JAK3 and GSK-3ß kinases in vitro and its binding affinities were mapped through the intermolecular interactions with each target in silico.

Electrochemical sensor based on biochar and reduced graphene oxide nanocomposite for carbendazim determination.

For the first time, a nanocomposite based on biochar and reduced graphene oxide (rGO) was employed to construct a modified carbon paste electrode and applied for the determination of carbendazim (CBZ). Biochar was obtained by through pyrolysis of Eichhornia crassipes biomass, also known how "Aguapé" at 400 °C. The modified electrode with our nanocomposite proposal shows to be able to preconcentrate CBZ and presented the highest analytical response in comparison to the unmodified electrode and by the electrodes prepared with the proposed materials separately. Using differential pulse voltammetry (DPV) under optimized conditions, the sensor showed a linear dynamic response (LDR) from 30 to 900 nmol L-1, a limit of detection (LOD) of 2.3 nmol L-1 and limit of quantification (LOQ) of 7.7 nmol L-1. No significant influence of inorganic ions or organic compounds on sensor response was verified, considering the recovery evaluation data. The proposed sensor was successfully applied for the determination of CBZ in spiked whole orange juice, lettuce leaves, drinking water, and wastewater samples. Good recovery values were found using the ex-situ methodology, showing excellent analytical performance of the electrochemical sensor based on biochar and rGO nanocomposite.

Assessing biochar applications and repeated Brassica juncea L. production cycles to remediate Cu contaminated soil.

Copper contamination and toxicity in soils is a worldwide problem, especially in areas where copper-based fungicides are applied. Indian mustard (Brassica juncea L.) plants are used in phytoremediation and are also edible crops commonly cultivated in organic agricultural areas. Application of biochar to Cu contaminated soils may reduce Cu availability and uptake, thereby allowing for greater Indian mustard production. A (3 × 2) + 1) experiment in a randomized complete block design was used to evaluate the effect of three different biochars (coconut shell, orange bagasse and sewage sludge) and two application rates (30 and 60 t ha-1) on Cu uptake by Indian mustard during three successive growth cycles and Cu immobilization in soil, under greenhouse conditions. Coconut husk biochar did not influence available soil Cu; however, its presence increased shoot Cu uptake by 117% and 38% in the two last growth cycles. Orange bagasse biochar, at the 60 t ha-1 application rate, reduced Cu availability, but it was not effective in reducing Cu uptake. Sewage sludge biochar did not affect Cu availability and caused an approximated 100% increase in shoot Cu uptake at the highest application rate. Therefore, the orange bagasse biochar is the most effective whereas the sewage sludge biochar is the least in Cu immobilization. None of the biochars was shown to be suitable as soil amendment to reduce the uptake of Cu by Indian mustard. However, coconut shell and sewage sludge biochar can be effectively applied to soil as an auxiliary tool to remediate Cu-contaminated soils.

Lotus corniculatus regulates the inflammation induced by bradykinin in a murine model of pleurisy.

This study evaluated the anti-inflammatory efficacy of the crude extract (CE), the fractions derived from hexane (HEX), ethyl acetate (AcOEt), n-butanol (BuOH), and aqueous (Aq) and isolated compounds (oleanolic acid or kaempferitrin) obtained from the aerial parts of Lotus corniculatus var. São Gabriel in mice with bradykinin-induced pleurisy. Swiss mice were used for the In Vivo experiments. Inflammatory parameters [leukocytes; exudate concentrations; myeloperoxidase and adenosine-deaminase activities, and nitric oxide and interleukin-17 levels] were evaluated 4 h after pleurisy induction. The crude extract of Lotus corniculatus, its derived fractions, and isolated compounds inhibited leukocytes and the exudate. This inhibitory effect was associated with decreased of myeloperoxidase and adenosine-deaminase activities, nitric oxide products, and IL-17A levels. Lotus corniculatus presented important anti-inflammatory action by inhibiting leukocyte influx and exudate concentrations. This effect was directly related to the inhibition of nitric oxide and interleukinin17 levels. Oleanolic acid and kaempferitrin can account for these anti-inflammatory effects.

Use of ozone in a pilot-scale plant for textile wastewater pre-treatment: physico-chemical efficiency, degradation by-products identification and environmental toxicity of treated wastewater.

In this study, ozonation of raw textile wastewater was conducted in a pilot-scale plant and the efficiency of this treatment was evaluated based on the parameters color removal and soluble organic matter measured as chemical oxygen demand (COD), at two pH values (9.1 and 3.0). Identification of intermediate and final degradation products of ozone pre-treatment, as well as the evaluation of the final ecotoxicity (Lumistox test) of pre-treated wastewater, was also carried out. After 4h of ozone treatment with wastewater recirculation (flow rate of 0.45 m(3)h(-1)) the average efficiencies for color removal were 67.5% (pH 9.1) and 40.6% (pH 3.0), while COD reduction was 25.5% (pH 9.1) and 18.7% (pH 3.0) for an ozone production capacity of 20 g h(-1). Furthermore, ozonation enhances the biodegradability of textile wastewater (BOD(5)/COD ratios) by a factor of up to 6.8-fold. A GC-MS analysis of pre-treated textile wastewater showed that some products were present at the end of the pre-treatment time. In spite of this fact, the bacterial luminescence inhibition test (Lumistox test) showed a significant toxicity reduction on comparing the raw and treated textile wastewater. In conclusion, pre-ozonation of textile wastewater is an important step in terms of improving wastewater biodegradability, as well as reducing acute ecotoxicity, which should be removed completely through sequential biological treatment.

Chemical composition and antibacterial activity of essential oils of Eugenia species.

The essential oils of the leaves of Eugenia brasiliensis, Eugenia beaurepaireana, and Eugenia umbelliflora were analyzed by GC-MS. The major compounds found in the oil of E. brasiliensis were spathulenol (12.6%) and tau-cadinol (8.7%), of E. beaurepaireana were beta-caryophyllene (8.0%) and bicyclogermacrene (7.2%), and of E. umbelliflora were viridiflorol (17.7%) and beta-pinene (13.2%). These oils were assayed to determine their antibacterial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. All of the oils analyzed showed antibacterial activity, ranging from moderate to strong, which was most accentuated for the E. umbelliflora and E. brasiliensis oils, which strongly inhibited the growth of S. aureus giving values of MIC = 119.2 and 156.2 microg/mL, respectively.

Characterization and potential uses of Copaifera langsdorfii seeds and seed oil.

Copaifera langsdorfii (Desf.) Kuntze (copaiba) seeds are abundantly produced and have not yet been characterized. The seed oil presents a characteristic odor of coumarin (250.1+/-6.57 mg/g determined through LC). The fatty acid composition of the oil was determined through CG/FID, being 45.3% linoleic acid, 32.3% monounsaturated, and 22.4% saturated fat. For the lipid-free seeds, the total carbohydrate, protein and moisture were 75.4%, 6.8% and 14.8%, respectively. The C. langsdorfii xyloglucan had an intrinsic viscosity of 804 mL/g, and the average molar mass (Mw) was 7.82 x 10(5)g/mol and Rg of 65 nm. The degree of polydispersion was 1.7, indicating the polydisperse family of polysaccharides. Its homogeneity, low degree of polymer contaminants and high intrinsic viscosity and molecular mass, represent good potential as a thickening agent. The presence of coumarin and xyloglucan as major components of C. langsdorfii seeds denotes its potential for use in the cosmetic or pharmaceutical industries.