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排序方式: 共有146条查询结果,搜索用时 140 毫秒
111.
Rodrigo Rodrigues Denise Bilibio Manuel S. V. Plata-Oviedo Edimir A. Pereira Marina L. Mitterer-Dalto Ellen C. Perin Solange T. Carpes 《Molecules (Basel, Switzerland)》2021,26(21)
The residue from commercial propolis extraction may have significant antioxidant power in food technology. However, among the challenges for using the propolis co-product as an inhibitor of lipid oxidation (LO) in baked goods is maintaining its bioactive compounds. Therefore, this study aimed to determine the propolis co-product extracts’ capability to reduce LO in starch biscuit formulated with canola oil and stored for 45 days at 25 °C. Two co-product extracts were prepared: microencapsulated propolis co-product (MECP) (with maltodextrin) and lyophilized propolis co-product (LFCP), which were subjected to analysis of their total phenolic content and antioxidant activity (AA). Relevant antioxidant activity was observed using the methods of analysis employed. The spray-drying microencapsulation process showed an efficiency of 63%. The LO in the biscuits was determined by the thiobarbituric acid reactive substances (TBARS) test and fatty acid composition by gas chromatography analysis. Palmitic, stearic, oleic, linoelaidic, linoleic, and α-linolenic acids were found in biscuits at constant concentrations throughout the storage period. In addition, there was a reduction in malondialdehyde values with the addition of both propolis co-product extracts. Therefore, the propolis co-product extracts could be utilized as a natural antioxidant to reduce lipid oxidation in fatty starch biscuit. 相似文献
112.
Christopher N. Schdle Stephanie Bader-Mittermaier Solange Sanahuja 《Molecules (Basel, Switzerland)》2022,27(6)
Low-calorie and low-fat foods have been introduced to the market to fight the increasing incidence of overweightness and obesity. New approaches and high-quality fat replacers may overcome the poor organoleptic properties of such products. A model of processed cheese spread (PCS) was produced as a full-fat version and with three levels of fat reduction (30%, 50%, and 70%). Fat was replaced by water or by corn dextrin (CD), a dietary fiber. Additionally, in the 50% reduced-fat spreads, fat was replaced by various ratios of CD and lactose (100:0, 75:25, 50:50, 25:75, and 0:100). The effect of each formulation was determined by measuring the textural (firmness, stickiness, and spreadability), rheological (flow behavior and oscillating rheology), tribological, and microstructural (cryo-SEM) properties of the samples, as well as the dynamic aroma release of six aroma compounds typically found in cheese. Winter’s critical gel theory was a good approach to characterizing PCS with less instrumental effort and costs: the gel strength and interaction factors correlated very well with the spreadability and lubrication properties of the spreads. CD and fat exhibited similar interaction capacities with the aroma compounds, resulting in a similar release pattern. Overall, the properties of the sample with 50% fat replaced by CD were most similar to those of the full-fat sample. Thus, CD is a promising fat replacer in PCS and, most likely, in other dairy-based emulsions. 相似文献
113.
Reactions of bis(pyridin-2-yl)ketone with tin tetrahalides, SnX4 (X = Cl or Br), or organotin trichlorides, R′SnCl3 (R′ = Ph, Bu or CH2CH2CO2Me), in ROH (R = Me or Et) readily produces RObis(pyridin-2-yl)methanolato)tin complexes, [5: RO(py)2C(OSnX3)] (5: R,X = Me,Cl; Et,Cl; Et,Br) or [6: MeO(py)2C(OSnCl2R′)] (R′ = Ph, Bu, CH2CH2CO2Me). In addition, halide exchange reaction between SnI4 and (5: R,X = Me,Cl) occurred to give (5: R,X = Me,I). The crystal structures of six tin(IV) derivatives indicated, in all cases, a monoanionic tridentate ligand, [RO(py)2C(O−)-N,O,N], arranged in a fac manner about a distorted octahedral tin atom. The Sn–O and Sn–N bonds lengths do not show much variation amongst the six complexes despite the differences in the other ligands at tin. 相似文献
114.
The sulfoxide thermolysis of the diastereoisomeric methyl (3R,4aS,10aR)‐6‐methoxy‐1‐methyl‐3‐(phenylsulfinyl)‐1,2,3,4,4a,5,10,10a‐octahydrobenzo[g]quinoline‐3‐carboxylates 3a and 3′b in toluene yields, by loss of benzenesulfenic acid, an almost 1 : 1 mixture of the vinylogous urethane 2b and the isomeric α‐aminomethyl enoate 2a . When this elimination is performed in acetic acid, the enoate 2a is formed rather selectively. The same solvent effects on the regioselectivity of the elimination of benzenesulfenic acid are observed with a simple sulfoxide of ethyl piperidine‐3‐carboxylate ( 7 ). 相似文献
115.
116.
Magda Ferreira Maria Ogren Joana N. R. Dias Marta Silva Solange Gil Luís Tavares Frederico Aires-da-Silva Maria Manuela Gaspar Sandra Isabel Aguiar 《Molecules (Basel, Switzerland)》2021,26(7)
Antimicrobial drugs are key tools to prevent and treat bacterial infections. Despite the early success of antibiotics, the current treatment of bacterial infections faces serious challenges due to the emergence and spread of resistant bacteria. Moreover, the decline of research and private investment in new antibiotics further aggravates this antibiotic crisis era. Overcoming the complexity of antimicrobial resistance must go beyond the search of new classes of antibiotics and include the development of alternative solutions. The evolution of nanomedicine has allowed the design of new drug delivery systems with improved therapeutic index for the incorporated compounds. One of the most promising strategies is their association to lipid-based delivery (nano)systems. A drug’s encapsulation in liposomes has been demonstrated to increase its accumulation at the infection site, minimizing drug toxicity and protecting the antibiotic from peripheral degradation. In addition, liposomes may be designed to fuse with bacterial cells, holding the potential to overcome antimicrobial resistance and biofilm formation and constituting a promising solution for the treatment of potential fatal multidrug-resistant bacterial infections, such as methicillin resistant Staphylococcus aureus. In this review, we aim to address the applicability of antibiotic encapsulated liposomes as an effective therapeutic strategy for bacterial infections. 相似文献
117.
Stella Maris Resende Josefredo R. Pliego Jr Solange Vandresen 《Molecular physics》2013,111(7):841-848
The atmospheric reaction of H2S with Cl was investigated using high level ab initio calculations and Canonical Variational Transition State Theory (CVTST). The adduct formation step is the dynamical bottleneck, and the rate constant was calculated to be 1.2 × 10?9 cm3 molecule?1 s?1, which is around ten times greater than the upper experimental value. Additional ab initio classical trajectory calculations show that the adduct formed in the initial collision can easily dissociate, recrossing the variational transition state. The stabilization of this species depends on the vibrational excitation of H2S molecule, which requires an almost collinear SH-Cl collision. These dynamical effects provide an explanation for the substantial error in the rate constant obtained using CVTST. 相似文献
118.
James L. Wardell Solange M. S. V. Wardell Janet M. S. Skakle John N. Low Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(7):o428-o430
Molecules of the title compound, C13H9IN2O2, are linked into [010] chains by a single C—H?O hydrogen bond and these chains are linked into (100) sheets by two independent aromatic π–π‐stacking interactions, each involving one of the two substituted arene rings. 相似文献
119.
Giorgio Abbiati Valentina Canevari Solange Caimi Elisabetta Rossi 《Tetrahedron letters》2005,46(42):7117-7120
The unusual [1,4]oxazino[4,3-a]indole nucleus was prepared, under mild reaction conditions, by reacting 1-alkynyl-1H-indole-2-carbaldehydes with various alkoxides, generated in situ from the corresponding alkyl, benzyl, allyl and propargyl alcohols. 相似文献
120.
Daniela Vieira Cortez Solange I. Mussatto Inês Conceição Roberto 《Applied biochemistry and biotechnology》2016,180(5):969-979
Cells of Candida guilliermondii permeabilized with Triton X-100 were able to efficiently produce xylitol from a medium composed only by d-xylose and MgCl2·6H2O in potassium phosphate buffer, at 35 °C and pH 6.5. Under these conditions, the results were similar to those obtained when cofactor and co-substrate or nutrients were added to the medium (about 95 % d-xylose was assimilated producing 42 g/L of xylitol, corresponding to 0.80 g/g yield and 2.65 g/L h volumetric productivity). Furthermore, the permeabilized cells kept the d-xylose assimilation in about 90 % and the xylitol production in approx. 40 g/L during three bioconversion cycles of 16 h each. These values are highly relevant when compared to others reported in the literature using enzyme technology and fermentative process, thereby demonstrating the effectiveness of the proposed method. The present study reveals that the use of permeabilized cells is an interesting alternative to obtain high xylitol productivity using low cost medium formulation. This approach may allow the future development of xylitol production from xylose present in lignocellulosic biomass, with additional potential for implementation in biorefinery strategies. 相似文献