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181.
Poliana Cristina Spricigo Banny Silva Barbosa Correia Karla Rodrigues Borba Isabela Barroso Taver Guilherme de Oliveira Machado Renan Ziemann Wilhelms Luiz Henrique Keng Queiroz Junior Angelo Pedro Jacomino Luiz Alberto Colnago 《Molecules (Basel, Switzerland)》2021,26(12)
The cambuci is a native Brazilian fruit from the Atlantic Forest biome. A soft and astringent pulp, a green color, and a sweet aroma are its main characteristics. Classical food quality attributes (fresh fruit mass, fruit height, diameters, total soluble solid, titratable acidity, and ratio) and the metabolic profile from ten accessions from three different locations were analyzed herein by analytical methods (refractometry and neutralization titration) and nuclear magnetic resonance spectroscopy. Concerning sugar content, sucrose was the predominant compound, with glucose and fructose alternating in second, depending on the accession. Citric acid was the most relevant acid, followed by shikimic and quinic acids in quite variable amounts. These three main acids vary in amounts for each accession. Ascorbic acid content emerges as an important quality attribute and makes this fruit nutritionally attractive, due to values comparable to those contained in citric fruits. The main amino acids identified in cambuci were glutamic acid individually or in comprising the tripeptide glutathione (glutamic acid, cysteine, glycine). The quality diversity of the evaluated accessions suggests the potentiality of cambuci use in future breeding programs. 相似文献
182.
Mozaniel Santana de Oliveira Jorddy Neves Cruz Oberdan Oliveira Ferreira Daniel Santiago Pereira Natanael Santiago Pereira Marcos Enê Chaves Oliveira Giorgio Cristino Venturieri Giselle Maria Skelding Pinheiro Guilhon Antnio Pedro da Silva Souza Filho Eloisa Helena de Aguiar Andrade 《Molecules (Basel, Switzerland)》2021,26(11)
Propolis is a balsamic product obtained from vegetable resins by exotic Africanized bees Apis mellifera L., transported and processed by them, originating from the activity that explores and maintains these individuals. Because of its vegetable and natural origins, propolis is a complex mixture of different compound classes; among them are the volatile compounds present in the aroma. In this sense, in the present study we evaluated the volatile fraction of propolis present in the aroma obtained by distillation and simultaneous extraction, and its chemical composition was determined using coupled gas chromatography, mass spectrometry, and flame ionization detection. The majority of compounds were sesquiterpene and hydrocarbons, comprising 8.2–22.19% α-copaene and 6.2–21.7% β-caryophyllene, with additional compounds identified in greater concentrations. Multivariate analysis showed that samples collected from one region may have different chemical compositions, which may be related to the location of the resin’s production. This may be related to other bee products. 相似文献
183.
Daniela Nunes da Silva Hanna Leijoto de Oliveira Keyller Bastos Borges Arnaldo César Pereira 《Electroanalysis》2021,33(2):506-514
The analysis of 17β-estradiol with high sensitivity and selectivity is extremely relevant to control the impacts that this compound can cause on health and the environment. Thus, we describe the development and application of a magneto carbon paste electrode based on magnetic molecularly imprinted polymer (MCPE-MMIP) for determination of 17β-estradiol. The analyte adsorbed on the MMIP was immobilized on the electrode surface by magnetic capture. The morphological and structural characterization of the obtained MMIP suggests that the material was effectively synthesized. MCPE-MMIP showed an improvement in the sensitivity for 17β-estradiol detection when compared to electrode configurations in the absence of this material. The optimum conditions (0.10 mol L−1 phosphate buffer pH 7.0) were reached by differential pulse adsorptive stripping voltammetry (DPAdSV), in which the method presented linearity ranged from 0.06 to 175 μmol L−1 with limits of detection and quantification of 0.02 and 0.06 μmol L−1, respectively. The proposed sensor was applied effectively in the analysis of 17β-estradiol in river water and raw milk samples, exhibiting excellent recovery values (between 96.20 and 104 %), which were confirmed by HPLC analysis. 相似文献
184.
Jonatas de Oliveira S. Silva Prof. Mércia V. S. Sant'Anna Dr. Ava Gevaerd MSc. Jéssica B. S. Lima MSc. Michael D. S. Monteiro Dr. Sanny W. M. M. Carvalho Dr. Eliana Midori Sussuchi 《Electroanalysis》2021,33(10):2152-2160
This study introduces modified carbon paste electrodes with carbon nitride nanosheets (CNNS) and outlines their application for the determination of hydroxychloroquine sulfate (HCQ) in tablets and synthetic urine samples. CNNS were synthesized by hydrothermal route (200 °C, 10 h) using melamine and citric acid as their precursors. The carbon nitride nanosheets-based electrode (CNNS/E) presented a linear dynamic range for HCQ (LDR), ranging from 10.0 nmol l−1 to 6.92 μmol l−1, and detection (LOD) and quantification limits (LOQ) of 0.16 nmol l−1 and 0.52 nmol l−1, respectively. LOD and LOQ were calculated by the equations: LOD=3(Sd/b), and LOQ=10(Sd/b). The modified sensor presented excellent relative standard deviations for parameters such as repeatability (2.39 % and 1.87 %) and reproducibility (3.22 % and 2.32 %) in HCQ oxidation peaks (1 and 2). The CNNS/E has not shown significant variations in its anodic signal intensity in the presence of some organic and inorganic substances. It is worth bearing in mind that CNNS/E can be easily manufactured and the sensor has the lowest HCQ detection limits reported so far. The proposed sensor was successfully applied for HCQ determination in tablets and synthetic urine, showing good recovery values and an error of 0.60 % about comparative method in tablet samples, assuring the quality of the method. 相似文献
185.
Duarte Valdyster Shirley Santos Rodrigues Aldimar Machado de Andrade-Filho Tarciso Silva Souza Divanizia do Nascimento de Novais Erico Raimundo Pereira Novais Andréa de Lima Ferreira de Oliveira Glaura Caroena Azevedo 《Structural chemistry》2021,32(4):1589-1595
Structural Chemistry - We investigatethe electronic and structural properties of two new amorphous materials, Bi6Ca2O28B12 and Bi6Ca2 O28B11:Tm, using density functional theory with a short-range... 相似文献
186.
A generalized Cho-Faddeev-Niemi ansatz for SU(3) Yang-Mills is investigated. The corresponding classical field equations are solved for its simplest parametrization. From
these solutions it is possible to define a confining non-relativistic central potential used to study heavy quarkonia. The
associated spectra reproduces the experimental spectra with an error of less than 3% for charmonium and 1% for bottomonium.
Moreover, the recently discovered new charmonium states can be accomodate in the spectra, keeping the same level of precision.
The leptonic widths show good agreement with the recent measurements. The charmonium and bottomonium E1 electromagnetic transitions widths are computed and compared with the experimental values. 相似文献
187.
de Souza EA Neves CA de Oliveira Campos LA Zanuncio JC Serrão JE 《Micron (Oxford, England : 1993)》2007,38(5):471-477
The effect of mating delay on the ovary structure of virgin queens of Melipona quadrifasciata anthidioides (Hymenoptera: Apidae) was investigated. Virgin queens 15, 20, 25 and 30 days old were dissected to analyze their degree of ovary degeneration. To verify whether the degeneration would cause permanent sterility, virgin queens of the same ages (15, 20, 25 and 30 days) were mated and accompanied for at least 14 days to verify whether there was physogastry and then dissected. The ovaries were analyzed by histology, histochemical tests and TUNEL to verify programmed cell death. The results showed that mating delay interrupted oogenesis preventing vitellogenesis. Mating delay results in ovary degeneration which increased with queen age. However, even when there was ovariole degeneration, 25-day-old virgin queens after mating presented normal ovariole activation. 相似文献
188.
Del Sordo Filho Giovanni Torrecilha Jefferson Koyaishi Scapin Marcos Antônio Oliveira Sonia Maria Barros da Silva Paulo Sergio Cardoso 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):61-70
Journal of Radioanalytical and Nuclear Chemistry - This study has evaluated chemical, radiological composition and determined the cation exchange capacity (CEC) for three commercially available... 相似文献
189.
Dr. Selina Beatrice van der Meer Theresa Seiler Christin Buchmann Georgia Partalidou Dr. Sophia Boden Dr. Kateryna Loza Dr. Marc Heggen Dr. Jürgen Linders Dr. Oleg Prymak Prof. Dr. Cristiano L. P. Oliveira Prof. Dr. Laura Hartmann Prof. Dr. Matthias Epple 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(4):1451-1464
Ultrasmall gold nanoparticles (diameter about 2 nm) were surface-functionalized with cysteine-carrying precision macromolecules. These consisted of sequence-defined oligo(amidoamine)s (OAAs) with either two or six cysteine molecules for binding to the gold surface and either with or without a PEG chain (3400 Da). They were characterized by 1H NMR spectroscopy, 1H NMR diffusion-ordered spectroscopy (DOSY), small-angle X-ray scattering (SAXS), and high-resolution transmission electron microscopy. The number of precision macromolecules per nanoparticle was determined after fluorescent labeling by UV spectroscopy and also by quantitative 1H NMR spectroscopy. Each nanoparticle carried between 40 and 100 OAA ligands, depending on the number of cysteine units per OAA. The footprint of each ligand was about 0.074 nm2 per cysteine molecule. OAAs are well suited to stabilize ultrasmall gold nanoparticles by selective surface conjugation and can be used to selectively cover their surface. The presence of the PEG chain considerably increased the hydrodynamic diameter of both dissolved macromolecules and macromolecule-conjugated gold nanoparticles. 相似文献
190.
Godoi C. M. Santos M. C. L. Silva A. J. Tagomori T. L. Ramos A. S. de Souza R. F. B. Neto A. Oliveira 《Research on Chemical Intermediates》2021,47(2):743-757
Research on Chemical Intermediates - PdxCuy/C catalysts combinations were employed to CH4 partial oxidation in mild condition using a solid electrolyte reactor—alkaline fuel cell type. The... 相似文献