Resumo em Inglês:

Fusel oil (FO) is one of the by-products of the sugar-alcohol industry, which has application as an additional source of higher alcohols for the production of esters with flavoring, fuels and lubricants properties, as well as additives in petroleum-based fuels and in pesticide formulations. Thus, this review is focused on the characteristics of FO and its applications as an acyl acceptor in transesterification and esterification reactions for esters production, its addition to fossil fuels, and the herbicidal and fungicidal potential of the compounds presented in its chemical composition. The operating conditions of the process, results obtained, and patented applications in the food, cosmetic, transportation and agricultural sectors are also reported and discussed. Furthermore, main trends, challenges and recommendations are proposed in order to overcome the disadvantages of applying FO in the reported sectors, as well as alternatives for the development of new lines of research are suggested.

Resumo em Inglês:

In this study, the preparation and adsorption properties of cobalt ferrite core-shell nanoparticles coated with silica and decorated with poly(4-vinylpyridine) (CoFe2O4@SiO2-P4VP) applied to bisphenol A (BPA) adsorption were described. The CoFe2O4-based core was coated by a nanometric layer of silica under Stöber conditions and followed by coating with poly(4-vinylpyridine) via surface polymerization in miniemulsion. The characterizations involved transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), Fourier transform infrared (FTIR), thermogravimetry (TGA), dynamic light scattering (DLS) and zeta potential. The polymeric core-shell nanoparticle showed a spherical structure with a magnetic core of ca. 11 nm and a layer of silica of ca. 4 nm. The amount of poly(4 vinylpyridine) that decorated the nanoparticle surface was verified by thermogravimetric analysis. CoFe2O4@SiO2-P4VP exhibited the capacity to adsorb bisphenol A. The chemometric model indicated a significant effect between the ionic strength and pH of the solution in the adsorption of bisphenol A. CoFe2O4@SiO2-P4VP presented a superior adsorption capacity towards BPA (46.6 mg g-1) in optimized conditions. The adsorption kinetics of BPA by CoFe2O4@SiO2-P4VP involved a pseudo-second order process. Also, the adsorption isotherm indicated a multilayer process with data well-adjusted by Freundlich equation. The nanomaterial CoFe2O4@SiO2-P4VP can be reused in adsorption of BPA for up to eight cycles.

Resumo em Inglês:

This study aimed to evaluate the effect of gamma irradiation (GI) on the physicochemical, technological, antioxidant and microbiological characteristics of different whole sorghum flours (WSF), as well as to characterize the profile of chemical constituents by paper spray mass spectrometry (PS-MS). The doses applied interfered in the staining characteristics of the evaluated flours, providing the darkening of the same. For the other physicochemical, technological, and antioxidant parameters, no significant influence of the process was observed. The fingerprint obtained in both ionization modes had not been influenced by irradiation, being flavonoids, phenylpropanoids, amino acids, benzoic acid derivatives, carboxylic acids, and sugars tentatively identified. In microbiological terms, there was a reduction of molds, yeasts, and Bacillus cereus in irradiated WSF compared to control (non-irradiated). Therefore, the application of low doses of gamma irradiation represents an advantageous alternative for the conservation of WSF and maintenance of bioactive compounds identified by the PS-MS technique.

Resumo em Inglês:

The classical alkylation reaction of benzene with isopropyl chloride catalyzed by the species AlCl3 and Al2Cl6 was studied using reliable calculations at M06-2X/def2-TZVPP//X3LYP/def2/SVP level of theory and SMD model for solvent effect. We evaluated the formation of dimers, trimers, tetramers, and pentamers and showed that Al2Cl6 dimers exist in greater proportion, in agreement with experimental observations. The experimental solubility of Al2Cl6 in benzene was also included in the theoretical kinetics analysis. The reaction catalyzed by AlCl3 species presents the highest barrier, in part due to unfavorable dissociation of the Al2Cl6 species. The mechanism via Al2Cl6 catalysis is more effective and even considering its low solubility, the calculated observed DG‡ is only 20.6 kcal mol-1, indicating a fast reaction rate. The mechanism involves the formation of the CH3CHCH3+…Al2Cl7- ion pair, which reacts with benzene to form a Wheland intermediate and this carbon-carbon bond formation step corresponds to the rate-determining one.

Resumo em Inglês:

The composition of human milk (HM) includes changes under the influence of factors such as genetics, stage of lactation, time of day, and even breastfeeding time. However, the authors are not aware of studies that evaluated the influence of breastfeeding time on fatty acid composition and cytokine. Thus, the objective of this study was to evaluate the influence of breastfeeding time (previous, intermediate, posterior milk) on kilocalorie concentration, fatty acid (FA) composition, and concentration of the cytokines interleukin-10 (IL-10), interferon factors for necrotic tumor (TNF-α) in HM colostrum. The results showed that the concentration of kilocalories was higher in posterior milk than in the previous, the composition of the main fatty acids found in the samples was influenced by the breastfeeding time, and the concentration of IL-10 and TNF-α was influenced in all samples with exception to mother 2. The principal component analysis explained 71% of the variances in the results. Thus, we concluded that the breastfeeding time is a factor that influences the concentration of kilocalories, and if it is necessary to use a more caloric milk, it is recommended to use the posterior milk; the FAs composition and the evaluated cytokines were also influenced by the breastfeeding time.

Resumo em Inglês:

The aim of this study was to develop a fast, simple and accurate analytical method for the classification of reference tablet analgesic drugs containing dipyrone, orphenadrine and caffeine using differential scanning calorimetry (DSC) and visible-near infrared spectroscopy (VNIRS) associated with one-class chemometric classification algorithm. The training set is based on reference medicine with 15 samples as target class. Three different brands with 10 samples each and five reference medicine samples, obtaining 35 samples, were used as the test set. Chemometric models based on principal component analysis (PCA) and data-driven soft independent modelling of class analogy (DD-SIMCA) were used to obtain the results. Two DD-SIMCA models obtained 100% sensitivity, specificity, and accuracy using DSC and VNIRS, both with a significance level of 0.01. This method using one-class classification as a chemometric tool proved to be a good alternative for quality control of pharmaceutical samples.

Resumo em Inglês:

Considering the relevance of natural products to the development of new drugs, this study focuses on the species Sida rhombifolia (L.), Malvaceae, widely used as a traditional remedy in several countries. The species is used to treat several diseases such as fevers, skin diseases, stomach pain, diarrhea, gum infection, conjunctivitis, urinary infections and inflammation. Many researchers around the word have investigated its pharmacological potential, and many uses have been confirmed. In spite of that, the phytochemical composition of its extracts is still poorly investigated. This research aims to make advances on the understanding of the constituents of S. rhombifolia identifying its alkaloidal compounds using ultra-high performance liquid chromatography coupled to mass spectrometry (UPLC-QTOF-MS/MS). By analyzing its alkaloidal fraction, it was possible to identify: 11-cryptolepine carboxylic acid (1), cryptolepine (2), quindoline (3), 11 methoxyquidoline (4), quindolinone (5), cryptolepinone (6), and 11-quindoline methyl ester (7). The alkaloids 1 and 7 are being reported for the first time from Sida genus. Based on the antimicrobial potential of cryptolepinone-type alkaloids, we prepared by semi-synthesis two cryptolepinone derivatives: 10-methylcryptolepinone (8) and the unreported compound 10-ethylcryptolepinone (9). Both derivatives were tested against fungal and bacterial strains and 10-methylcryptolepinone (8) showed strong activity against Cryptococcus neoformans, Candida albicans, Candida tropicalis, Aspergillus fumigatus and Aspergillus flavus.

Resumo em Inglês:

This study indicates the use of Phallusia nigra as a potential biomonitor of mercury contamination. In this way, Hg levels were measured in seawater and different parts of ascidians (tunic, hepatopancreas, and branchial basket) from eight different sites in the Todos os Santos Bay, Salvador-Bahia. The ascidians were lyophilized, weighed, and taken to the DMA-80 (direct mercury analyzer); the method accuracy was confirmed by analyzing the certified material DORM 4 muscle tissue and MEES-3 marine sediment with a confidence level of 95%. The results were evaluated through the Tukey’s test and it was possible to observe a higher concentration of Hg (82.00 312.7 ng g-1) in the branchial basket, followed by the hepatopancreas (69.67 130.7 ng g-1) and tunic (21.63-33.27 ng g-1). Thus, the branchial basket was the only tissue capable of identifying spatial differences in pollution between the points.

Resumo em Inglês:

The aim of this work was to identify and quantify the metabolites present in the roots of Combretum lanceolatum inoculated with its endophytic fungi. The metabolomics was accomplished using the 1H nuclear magnetic resonance (NMR) spectral data and evaluated via rNMR software and Madison Metabolomics Consortium Database (MMCD). The principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) showed that plants inoculated with Trichoderma spirale (Ts) present differentiation and discrimination over the time compared to control. Seven days after Ts fungal inoculation, 15 metabolites were identified at different concentrations comparing to the control plants. The plants inoculated with Ts fungus present the metabolites spermidine and pantothenate in higher concentrations and 3-hydroxybutyric acid and b-alanine in lower concentrations compared to control plants, indicating any response to biotic stress. These metabolites are involved in various plant processes, including secondary metabolites biosynthesis, energy metabolism and self-defense. Therefore, this work demonstrates the diversification of primary metabolites composition influenced by endophytes inoculation.

Resumo em Inglês:

The 1,4-naphthoquinones are an important group of compounds intensively studied because of their wide range of biological activities. Four 2-chloro-3-(substituted-phenylamino)-1,4 naphthoquinone derivatives were synthesized, and the vibrational modes of these molecules were assigned using Raman and Fourier transform infrared spectroscopy (FTIR) techniques. In addition, X-ray studies were performed for one of these derivatives. Density functional theory (DFT) calculations were also developed for these compounds and presented. In summary, the results obtained from these studies can assess chemical changes in the structures of functionalized quinones and the discovery of candidate biologically active compounds.

Resumo em Inglês:

Chemical modification reactions are viable alternatives for improving the properties of starch because they allow the insertion of molecules that change the original behavior of the polymer. Glycidyl methacrylate (GMA) is an example of a vinylic molecule added to starch to decrease its hydrophilicity and improve mechanical properties. This modification reaction is affected by parameters like the volume of the modifier, time, and temperature. Furthermore, the correlation between these parameters might change the response of an individual parameter on the degree of substitution (DS), crystallinity (Xc), and molecular-weight-related parameters. This work evaluated how these effects and their correlations would affect DS, Xc, molecular weight, and polydispersity index (PDI) of starch. The results suggested that, while higher volumes of GMA and temperatures decreased the DS and Xc, the correlation between them increased the DS by 2.47, and Xc by 1.25. On the other hand, higher temperatures also favored the occurrence of hydrolysis. Also, although none of the parameter correlations had a significant effect on the assessed properties (at 95%), the statistical analysis confirmed that the correlation between two parameters changed the effect of individual parameters.

Resumo em Inglês:

The occurrence of emerging contaminants (ECs) in the aquatic systems under influence of urban areas have been considered as an environmental marker of anthropogenic contamination. In this study, 10 ECs were investigated in sediment samples from Santos Bay using a quick, easy, cheap, effective, rugged, and safe method with determination by liquid chromatography tandem mass spectrometry. The method showed acceptable accuracy (51-116%) and precision (relative standard deviation (RSD) ≤ 9), limits of quantification in ng g-1 levels and matrix effect lower than 29%. Environmental occurrence of benzophenone-3, caffeine, ketoconazole and triclocarban was detected in two campaigns (2015 and 2019), with concentrations ranging from < 1 to 470 ng g-1. Caffeine and triclocarban were the most abundant target chemicals occurring in up to 71 and 100% of the sample point, respectively. The results indicated that ECs in sediment samples came from diffused sources as the discharge of treated and untreated sewage in the estuary.

Resumo em Inglês:

Activated carbons (ACs) from olive stone were prepared using CO2, steam, KOH, and H3PO4 as activating agents. The resultant activated carbons were characterized by proximate and ultimate analysis, N2 adsorption (Brunauer-Emmett-Teller (BET) method), iodine number, Boehm titration, temperature-programmed desorption (TPD), and Fourier transform infrared spectroscopy (FTIR). Ammonia (NH3) was used as a test molecule to be adsorbed. The BET surface areas of the ACs obtained ranged from 1000 to 1986 m2 g-1. Type I isotherms were obtained for all the samples, although steam and H3PO4 ACs showed a significant mesopore contribution. KOH activation resulted in carbon with a high microporosity (98%) and high iodine adsorption (1030 mg g-1). KOH AC prepared with a KOH/pyrolyzed char weight ratio of 2 and at 900 °C showed the highest NH3 adsorption (252 mg g-1), favored by the high microporosity and adequate acidity. Chemical activation (KOH and H3PO4) promotes higher NH3 adsorption than the physical ACs prepared (CO2 and steam). Langmuir and Freundlich adsorption equilibrium models were used to correlate the NH3 adsorption isotherms, obtaining the best fit for the Freundlich equation. The results indicated that olive stone-based activated carbon could be used for commercial AC to remove NH3 from gaseous streams.

Resumo em Inglês:

Florpyrauxifen-benzyl is the new active ingredient authorized by Brazilian legislation, which acts as herbicide and may be used to control weeds in rice cultivation, but studies on toxicity to humans and the environment are still under review. Due to recent insertion in the world pesticide market, there are still few studies related to the extraction and detection methodologies of this compound. Therefore, this study aimed to optimize and validate solid-liquid extraction with low temperature purification (SLE-LTP) for determining florpyrauxifen-benzyl in soil using high-performance liquid chromatography coupled to a diode array detection (HPLC-DAD). The results showed that the best conditions were achieved using Poroshell column, a temperature of 30 °C, mobile phase composition of acetonitrile:water (85:15 v/v) acidified with formic acid 0.1% (v/v), a flow rate of 0.3 mL min-1, and 243 nm as the wavelength. The best extracting phase was acetonitrile acidified with formic acid 0.1% (v/v) which achieved a recovery rate ca. 100% and relative standard deviation (RSD) less than 3.9%. The methodology was precise, accurate, linear and selective, with a limit of quantification of 20 µg kg-1. The stability study of this compound in soil showed that approximately 17.5 days is the half-life of florpyrauxifen-benzyl in soil.