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361.
Cristiane Y. KawasokoCarlos E.D. Nazario Amanda S. SantanaLuiz H. Viana Gabriela R. HurtadoFrancisco A. Marques Gustavo FrenschPaulo R. de Oliveira Palimécio G. Guerrero Jr.Diego B. Carvalho Adriano C.M. Baroni 《Tetrahedron letters》2011,52(46):6067-6071
The hydroalumination of silylacetylenes with DIBAL-H followed by the addition of n-butyllithium generated in situ the (Z)-β-vinylorganosilane alanates intermediates, which were trapped with butyltellurenyl bromide (C4H9TeBr), furnishing exclusively the (E)-1-butyltelluro-1-tri(organyl)silyl-2-organyl-1-alkenes in 45-70% yields. These telluro(silyl)ketene acetals were utilized as substrates in Sonogashira cross-coupling Pd-catalyzed reactions, furnishing the (Z)-1,4-diorganyl-2-tri(organyl)silyl-1-buten-3-ynes with total control of regio- and stereochemistry in 62-80% yield. 相似文献
362.
Cliciane Guadalupe de Jesus Cristiane Maria Sampaio Forte Karen Wohnrath Christiana Andrade Pessôa Janete Elisa de Sá Soares Sérgio Toshio Fujiwara Pedro de Lima‐Neto Adriana Nunes Correia 《Electroanalysis》2011,23(8):1814-1820
A (SiPy+Cl?/CuTsPc)5 layer‐by‐layer film was employed for the electroanalytical determination of promethazine hydrochloride in BR buffer pH 5.0 with peaks at 0.48 and 0.79 V. After optimisation of the square‐wave parameters (f=100 s?1, a=40 mV and ΔEs=2 mV), the peak at 0.79 V was used for quantification and a detection limit of 8.71×10?9 mol L?1 and a quantification limit of 9.31×10?8 were calculated. The applicability of this procedure was tested on commercial formulations of promethazine hydrochloride by observing the stability, specificity, recovery and precision of the procedure in complex samples, without any preliminary treatment. 相似文献
363.
Tufy Kabbas Junior Cristiane de Moura Mariana Araújo Vieira do Carmo Luciana Azevedo Luis Antnio Esmerino Rosangela Capuano Tardivo Petri Kilpelinen Daniel Granato 《Molecules (Basel, Switzerland)》2021,26(13)
The aim of this study was to compare the influence of the extraction method, chemical composition, antimicrobial effects, antioxidant activity, and cytotoxicity on human cells of the non-polar extracts of grape (Vitis labrusca) and blackberry (Rubus fruticosus) seeds. The Soxhlet (Sox), Bligh–Dyer (BD), and ultrasound (US) methods were used for extractions. For blackberry non-polar seed extract, extraction via the BD method showed the highest mean values of total phenolic content (TPC), expressed in milligrams of gallic acid equivalent per 100 mL of non-polar seed extracts (102.37 mg GAE/100 mL), and higher antioxidant activity in relation to the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, expressed in milligrams of gallic acid equivalent per 100 mL of non-polar seed extracts (11.50 mg AAE/100 mL), if compared with the Sox and US extractions. Similar results were obtained for the non-polar grape seed extracts, where BD extraction obtained the highest values for TPC (28.61 mg GAE/100 mL) and DPPH (35.36 mg AAE/100 mL). The type of extraction method had an impact on the composition of fatty acids. Only the non-polar blackberry and grape seed extracts obtained via the Sox method showed some in vitro inhibitory effect against Escherichia coli (IAL 2064) and Staphylococcus aureus (ATCC 13565). Regardless of the extraction method used, the non-polar blackberry and grape seed extracts did not decrease the cell viability (IC50 >1000 µg/mL) of cancer and normal cell lines, thus indicating the relative safety of the extracts. All the seed extracts decreased the generation of reactive oxygen species in the cell lines. Blackberry and grape seed lipid fractions can be utilized as antioxidants, and the extraction methods used cause significant changes in relation to their bioactivity and chemical composition. 相似文献
364.
Matheus Mikio Takeyama Mrcia Corrêa de Carvalho Helena Sacco Carvalho Cristiane Rodrigues Silva Ana Paula Trovatti Uetanabaro Andrea Miura da Costa Joseph A. Medeiros Evaristo Fbio Csar Sousa Nogueira Ana Elizabeth Cavalcante Fai Maria Gabriela Bello Koblitz 《Molecules (Basel, Switzerland)》2022,27(15)
A sequential design strategy was applied to optimize the secretion of pectinases by a Saccharomyces cerevisiae strain, from Brazilian sugarcane liquor vat, on passion fruit residue flour (PFRF), through solid-state fermentation (SSF). A factorial design was performed to determine the influence variables and two rotational central composite designs were executed. The validated experimental result was of 7.1 U mL−1 using 50% PFRF (w/w), pH 5, 30 °C for 24 h, under static SSF. Polygalacturonase, pectin methyl esterase, pectin–lyase and pectate–lyase activities were 3.5; 0.08; 3.1 and 0.8 U mL−1, respectively. Shotgun proteomics analysis of the crude extract enabled the identification of two pectin–lyases, one pectate–lyase and a glucosidase. The crude enzymatic extract maintained at least 80% of its original activity at pH values and temperatures ranging from 2 to 8 and 30 to 80 °C, respectively, over 60 min incubation. Results revealed that PFRF might be a cost-effective and eco-friendly substrate to produce pectinases. Statistical optimization led to fermentation conditions wherein pectin active proteins predominated. To the extent of our knowledge, this is the first study reporting the synthesis of pectate lyase by S. cerevisiae. 相似文献
365.