Food additives are chemical substances added to improve organoleptic characteristics, in this context, there are several synthetic dyes, such as sunset yellow, tartrazine, erioglaucine, allura red, indigo carmine, and new coccine, that can also be identified through different analytical techniques such as infrared spectroscopy, UV-Vis spectrophotometry, high performance liquid chromatography with diode array detector and mass spectrometry. Therefore, the objective of this work was to compare methods developed for different analytical techniques, in order to identify the one that presents greater efficiency in certain applications. For this, the patterns of the dyes were analyzed, as well as their mixtures and foods that had them. As a result, the CLAE-DAD presents excellent selectivity and linearity of the calibration curves, but it presents higher LD and LQ values when compared to the UV-Vis, in turn the infrared provides information regarding functional groups and bonds. Mass spectrometry showed great capabilities in identifying the molecular formula and better selectivity in the absence of the erioglaucine dye. It is not feasible to indicate the best or worst analytical approach, but it is possible to point out which one is more suitable for each application. Regarding the quantification capacity, chromatography and UV-Vis are good alternatives, but in mixtures containing more than one dye, CLAE-DAD is more suitable due to the better selectivity. Regarding the identification capacity, mass spectrometry, especially FT-ICR MS, is the most appropriate technique to propose molecular formulas due to its high resolution and mass accuracy. The advantage of FTIR was the easier sample preparation, being able to analyze the dyes in the solid state.

In recent years, technological development in analytical instrumentation has progressed vigorously, which has allowed the evolution of analytical techniques that play an indispensable role within society, highlighting mass spectrometry. Parallel to the technological advance of this technique, the development of new ionization methods that are simpler, faster, and allow direct analysis without the need for prior treatment or sample processing is underway. The methods of ambient ionization derived from paper spray have been developing rapidly in current days, mainly in the forensic field, due to the chemical modifications made in the paper substrate and the introduction of new types of organic materials that function as a probe/substrate to collect, store, and ionize the sample, then enabling more efficient and selective analyzes. This review highlights direct analyzes by applying paper spray ionization in the forensic field and some variations of this technique, including Thread Spray Ionization (TSI) when a fabric thread is used; Touch Spray Ionization (TSI), which uses materials such as metallic needles, medical swabs, and wooden sticks; Fiber Spray Ionization (FSI), which applies polymeric fibers as substrates.

Eugenol (C10H12O2, 4-allyl-2-methoxyphenol) is a phenolic natural product that has several biological activities and possibilities of applications. It is herein described the synthesis of eugenol-fluorinated triazole derivatives and evaluation of their fungicidal activity. The reaction of eugenol with epichlorohydrin resulted in the preparation of (±)-2-((4-allyl-2-methoxyphenoxy)methyl)oxirane (1) in 88% yield. The azidolysis of 1 with sodium azide gave the azido-alcohol (±)-1-(4-allyl-2-methoxyphenoxy)-3-azidopropan-2-ol (2) in 94% yield. The CuAAc reaction between compound 2 and different terminal alkynes afforded a series of eleven derivatives (3a 3k) within 48-80% yield. All the synthesized compounds were characterized by infrared (IR) and nuclear magnetic resonance (1H and 13C) spectroscopies and high-resolution mass spectrometry. The in vitro inhibitory activity of the compounds on the mycelial growth of a strain of Colletotrichum sp., that causes anthracnose disease on papaya fruits, was evaluated. The best result was observed for compound 1-(4-allyl-2-methoxyphenoxy)-3-(4-(2-fluorophenyl)-1H-1,2,3-triazol-1-yl)propan-2-ol (3d) that showed a mean growth-inhibition zone of 5.10 mm in a well-diffusion assay, and may serve as a template for additional structural modifications, aiming for more potent fungicidal activity.

This study proposed using a portable microscope combined with a smartphone and application (PhotoMetrix® application) to evaluate the authenticity of Brazilian banknotes (R$50 and R$100) and national driver’s licenses (NDL) through image acquisition (Samsung S7) and chemometric treatment (principal component analysis (PCA)). Six regions of the banknote were analyzed: holographic band; lower and upper tactile regions containing the number referring to the value of the note; microprints above the effigy (obverse); and numbers and the surroundings of the animal formed by microprints (reverse). For NDLs, the regions were the following: the coat of arms of the republic; the state map with microprints; optical ink variation; distorted positive microletters with technical failure; negative guilloche; typographic numbering; micro letter wire; and region with line printing. For the chemometric study with Photometrix®, we selected a region of interest (ROI) of 32 × 32 and 64 × 64 pixels with autoscaled data using the channels red (R), green (G), blue (B), hue (H), saturation (S), value (V), lightness (L) and intensity (I). We obtained excellent results for differentiating banknotes and NDLs, both by visual and chemometric analyses (PCA). This study demonstrates the effectiveness of using a portable microscope and a smartphone as a portable forensic tool that is fast, robust, low-cost and reliable.

Beer is commonly produced with four inputs: water, malt, hops, yeast and, in some cases, brewing adjuncts. Industrial and artisanal processes essentially follow the same steps and may undergo minor changes due to the style of beer. Despite this, many consumers attribute higher quality to craft beer compared to industrial ones. In this study, we applied the analytical techniques of infrared (IR), hydrogen nuclear magnetic resonance (1H NMR) and mass spectrometry (ESI(±)FT-ICR MS) to discriminate craft beers from industrial ones (brands common to the Brazilian market). In addition, Partial Least Squares (PLS) and Support Vector Machine (SVR) regression were used to estimate some beer properties (pH, total acidity (meq·L-1, color (EBC), bitterness (IBU), alcohol content (%v/v) and density (g·mL-1)). The use of the IR allowed the identification of vibrations attributed to chemical compounds common to beverages, such as water (3320 and 1640 cm-1), carbohydrates (1500 cm-1) and ethanol (1050-1040 and 875-865 cm-1). 1H NMR showed good applicability in identifying classes of organic compounds in the beverage, where signs attributed to alcohols, organic acids, carbohydrates and amino acids were observed. The ESI(+)FT-ICR MS allowed the identification of chemical compounds present in beverages, allowing the construction of a fingerprint of the beers. In addition, the application of chemometric tools enabled the prediction of physicochemical properties, presenting promising results in the prediction of alcohol content (RMSEC 0.2430 and RMSEP 0.3929) and bitterness (RMSEC 1.3022 and RMSEP 1.6008), and also in the classification regarding the manufacturing process (craft and industrial beer).

This work describes the synthesis and application of an europium(III) complex, [Eu(TTA)3(2-pyr) (H2O)], containing 2-thenoyltrifuoroacetonate (TTA) and 2-pyrrolidone (2-pyr) as ligands, obtained as white solid and soluble in ethanol. In solution, the complex showed red emission, characteristic of the EuIII emission in the solid state (λexc = 375 nm and λem = 612 nm). The complex was tested with PbII, CdII, and HgII ions in water. The effect of metal ions was monitored and evaluated by hypersensitive transition 5D0 → 7F2 (612 nm). The results show that PbII suppresses the complex luminescence and present high sensitivity, according to the values for the Stern-Volmer constant (K SV = 2300 L mol−1), showing good linearity, i.e., determination coefficient (R 2) of 0.9913, and low limit of detection (LOD = 6.03 µM). Luminescence quenching increased with the increasing concentration of PbII. These results indicate that the synthesized complex is a potential luminescent sensor for detecting PbII in a simple and fast way, being applicable for routine environmental analysis. When applied as an ethanol sensor in gasoline, the complex hypersensitive transition intensity decreased with the increasing volume of ethanol in gasoline, reaching the values of R 2 = 0.9815 and LOD = 4.94% v/v.

RESUMO: O acúmulo de nutrients em plantas/frutos variam de acordo com o estádio de desenvolvimento das culturas, sendo que sua quantificação é importante na determinação da exportação de nutrientes para o planejamento da adubação e para o balanceamento de nutrientes. Esse estudo objetivou determinar o acúmulo de nutrientes em diferentes partes dos cachos de Piper nigrum ‘Bragantina’ colhidos em dois estágios de maturação (coloração da casca verde e coloração da casca vermelha). As avaliações foram feitas separadamente nos cachos de Piper nigrum com coloração verde (fruto e pedúnculo) e vermelha (grão, casca e pedúnculo), em que os cachos foram colhidos, secos e as partes foram separadas para análises químicas. N e Mn foram os macro e micronutrientes mais acumulados nos frutos dos cachos com coloração da casca verde e nos grãos dos cachos com coloração da casca vermelha, enquanto K e B foram mais acumulados em outras partes da planta, independente do estágio de maturação. O processo de removação da casca para produção de pimenta branca levou a uma diferença na concentração e no acúmulo de nutrientes nos frutos de pimenta preta e nos grãos de pimenta branca. Uma contribuição significativa para entrada de nutrientes pode ser obtida se as cascas e pedúnculos forem mantidos na área de cultivo, o que diminui a dependência de fertilização, contribuindo para uma agricultura mais sustentável.

ABSTRACT: Nutrients accumulation in plants/fruits varies according to the crop development stage and its quantification is important to determine nutrients exportation for fertilization planning and nutrient balancing. This study determined the accumulation of nutrients in different parts of Piper nigrum ‘Bragantina’ spikes harvested at two ripening stages (still-green and red-colored spikes). Assessments in separate parts of still-green spikes (fruits and peduncles) as well as in red-colored spikes (grains, flesh and peduncles) were performed. Piper nigrum spikes were harvested, dried, and the parts were thereafter separated for chemical analysis. N and Mn were the macro and micronutrient most accumulated in the fruits of still-green spikes and in the grains of red-colored spikes, while K and B were most accumulated in the other parts of black pepper assessed, regardless of the ripening stage. The process of removing the flesh from the fruits for white pepper production led to a difference in nutrient concentration and accumulation between the fruits of still-green spikes and the grains of red-colored spikes. A significant contribution of nutrient input can be achieved by maintained flesh and peduncles in the crop area, decreasing the dependence of external fertilizers and thus contributing to a more sustainable agriculture.

Mass spectrometry (MS) is a high-performance analytical technique that allows a measurement of the mass/charge (m/z) ratio of compounds present in a sample. MS is able to separate two m/z ions with determined values (mass resolution), being an important characteristic, especially in the analysis of biochemical components and complex mixtures. Mass analyzers define the resolving power and accuracy of different types of mass spectrometers. Herein, the performance of two mass analyzers (Fourier Transform Ion Cyclotronic Resonance (FT-ICR) and quadrupole ion trap (LTQ)) was tested on low (Mw = 165-679 Da) and high (Mw = 783-8.58 kDa) molecular weight molecules (Phenacetin, Procaine, Benzocaine, Caffeine anhydrous, Lidocaine, two metal porphyrin standards, the first cobalt and the second vanadium, and two protein standards, Ubiquitin and Beauvericin), and finally, for an oil sample. LTQ-MS and FT-ICR-MS had similar performance and high reproducibility. However, the mass accuracy and resolution power of the FT-ICR (error lower than 5 ppm and RP higher than 400,000) was higher, being therefore, it was more suitable for the analysis of proteins and oil, for instance. On the other hand, the CID analysis via LTQ demonstrated its applicability in fragmentation experiments, being able to determinate the chemical connectivity of organic compounds in non-complex mixtures.

The objective of this work was to control the purity level of canephora coffees (Conilon coffee) from the state of Espírito Santo (Brazil), as a function of the addition of grounds produced by the coffees themselves using a portable microspectrometer in the infrared region. (microNIR), associated with chemometric tools. The PCA model grouped the coffees according to the level of adulterant in the samples and showed that the presence of moisture and polysaccharides is important for the discrimination between pure and adulterated samples. PLS-DA and SIMCA classification models were built with commercial samples and resulted in the discrimination of authentic and non-authentic samples with accuracy values above 90% and 82% for PLS-DA and SIMCA, respectively. The quantification results presented by the PLS model were satisfactory for all models, reaching the best results at 75 °C with RMSEP values of 6.13 wt%, R2p = 0.9917; and LOD in the range of 5.6-8.9 wt%; LOQ = 17-26.8 wt%, according to IUPAC; relative standard deviation for repeatability of 1.0 and 1.7 wt%; and intermediate precision of 3.4 and 1.1 wt% for low (<10 wt%) and high (≈ 90 wt%) levels of adulterants, respectively. Therefore, this work represents the first exploratory study to analyze adulterations with coffee grounds by portable NIR, demonstrating the potential of the equipment against this type of adulteration.

In this work, three complexes were synthesized from the trivalent europium ion (EuIII), using the picrate anion (pic), and delta-valerolactam (DVL), epsilon-caprolactam (EPK), and oenantholactam (OEN). The synthesized complexes [Eu(pic)3·(DVL)3], [Eu(pic)3·(EPK)3], and [Eu(pic)3·(OEN)3] were studied as luminescent markers for application as security elements in Brazilian banknotes. All complexes showed red color emission with absorption at 397 nm and emission at 614 nm. Qualitative luminescence tests were performed on R$10, R$20, R$50, and R$100 Brazilian banknotes. The complexes were applied on the surface of the banknotes and were exposed to different wavelengths of 254, 312, 365, and 320-400 nm. The chemical profiles of the complexes were identified on the banknotes employing the laser desorption ionization mass spectrometry (LDI (±) MS) technique. Generally, tests were promising, and can thus provide a simple, fast, and easy method to identify the authenticity of questioned documents, with an average cost of R$0.65 per mg.

It is herein described the synthesis of a series of thirty novel 1,2,3-triazole-1,4 disubstituted compounds inspired on the known SRPKs inhibitor N-(2-(piperidin-1-yl)-5-(trifluoromethyl)phenyl)isonicotinamide (SRPIN340) and biological evaluation of them against human glioblastoma multiforme cell line U87MG. Starting with 1-fluoro-2 nitro-4-(trifluoromethyl)benzene (1), the substances were prepared via a five-step synthetic route. The crucial step corresponded to the copper-catalyzed cycloaddition reaction between trifluoromethyl phenyl azides and different alkynes. In general, the compounds were obtained with good yields and they were characterized utilizing spectroscopic (IR and NMR) and spectrometric (HRMS) techniques. The evaluation of the synthesized compounds at three different treatment time (24 h, 48 h, and 72 h) and concentrations (50, 100, and 150 µmol L-1) revealed that five derivatives were capable of reducing cell viability by 50% after 72 h of treatment at the highest concentration. On the contrary, three derivatives significantly increased cell viability being this effect more pronounced after 48 h of treatment. In this regard, it stands out the compound 2-((1-(2-morpholino-5-(trifluoromethyl)phenyl)-1H-1,2,3-triazol-4-yl)methyl)isoindoline-1,3-dione (7) which increased cell viability in approximately 300% after 48 h of treatment at 100 µmol L-1. The substances that increased cell viaiblity present as common structural features the presence of a saturated nitrogen-containing six-membered ring and carbonylated fragments.

Many instrumental techniques are used to monitor the quality of food products, highlighting near infrared spectroscopy (NIRS). In order to determine the authenticity of 60 commercial oil samples seized by the Espírito Santo state police, this work used a portable spectrometer in the NIR region associated with chemometric tools such as principal component analysis (PCA) and partial least squares regression (PLS) to classify and quantify possible adulterants present such as soybean oil. In addition, physicochemical tests (acidity, peroxide and ultraviolet absorption) were carried out on commercial samples. The PLS regression model built to quantify soybean oil showed a coefficient of determination (R2) greater than 0.99, showing itself to be satisfactory. The results showed that all samples analyzed had a high content of adulterant and cannot be classified as extra virgin olive oil.

Wax deposit is of a great concern in the petroleum industry and causes partial or total blockage of the pipelines. In this work, four Brazilian crude oils (P1-P4) and five inhibitors solutions (I1-I5) were used associating rheology results to understand, at a molecular level, the characteristics of the saturated fractions by high-resolution mass spectrometry (Orbitrap coupled to atmospheric pressure chemical ionization (APCI) source) and two-dimensional gas chromatography coupled to mass spectrometry (GC × GC-MS). The effectiveness of wax inhibitors can be demonstrated by the viscosity decrement. The characterization of the saturated fractions by GC × GC-MS and high resolution mass spectrometry showed that is possible to conclude that inhibitor I1 favored the inhibition process of paraffins when oils have a smaller and monocyclic saturated chain hydrocarbon (HC) profiles, whereas for oils with larger amounts of polycyclic chain HCs, the inhibitor I4 appeared to be the alternative.

The semi-synthesis of 11 isatin derivatives was achieved through bimolecular nucleophilic substitution and click chemistry. Seven new compounds were obtained. All chemical structures were determined by infrared spectroscopy (IR), nuclear magnetic resonance spectrometry (NMR) and high-resolution mass spectrometry (HRMS) data. These derivatives were evaluated for their anti-GSK-3b activity and all isatin derivatives (N-alkyl and 1,2,3-triazolic) exhibited strong inhibitory activity, with 2b and 4h exhibiting remarkable potency. In addition, docking studies were performed with 2b and 2e models to unravel the molecular mechanism underlying the polar interactions on the GSK-3b ATP-binding site.

New Schiff base compound N, N’-bis-(4-hexadecanate)-salicylethylenediamine (named IM) was synthesized, and characterized via infrared and nuclear magnetic ressonance spectroscopies. IM was tested as corrosion inhibitor and antioxidant in soybean biodiesel. Corrosion studies were developed with AISI 1020 carbon steel in a three-step accelerated corrosion assay and IM inhibitory activity was evaluated using microscopic techiniques: optical microscopy (OM), scanning electron microscopy (SEM) and atomic force microscopy (AFM). In 750 ppm concentration, IM showed better inhibitory activity compared to commercial compounds tert-butylhydroquinone and pyrogallol, reducing root-mean-square roughness (Rq) from 37.8 to 11.7 nm and peak-peak height (PP) from 454.1 to 120.2 nm after 8 days of immersion. Antioxidant studies were conducted using the PetroOXY equipment. In 250 ppm concentration, IM showed better antioxidant activity as metal chelator, reducing biodiesel oxidation induced by copper on biodiesel. In this concentration, IM increased the induction period from 3.0 to 5.8 h. Furthermore, the new Schiff base acts as an oxygen scavanger. This is a great property because it reduces oxygen concentration in biodiesel, reducing metal corrosion reactions.