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131.
Casaburi A Aristoy MC Cavella S Di Monaco R Ercolini D Toldrá F Villani F 《Meat science》2007,76(2):295-307
In this study, two strains of Staphylococcus xylosus isolated from traditional fermented sausages of Vallo di Diano (Southern Italy) were used in combination with an acidifying strain of Lactobacillus curvatus as starter culture for the production of fermented sausages. Two starter formulation were developed combining the proteolytic but not lipolytic (prt(+), lip(-)) S. xylosus CVS11 with the L. curvatus AVL3 (starter S1) and the S. xylosus FVS21 (prt(-), lip(+)) with the same strain of L. curvatus (starter S2). Proteolysis and lipolysis were observed during ripening by the increase in total free amino acids (FAA) and free fatty acids (FFA), respectively. Such activities were observed in both started and non started sausages (control). Moreover, the proteolytic and lipolytic activities were detected in products started by both formulations irrespective of the presence of such activities in the strains used. Therefore, it was not possible to conclude whether the effect of proteolysis and lipolysis during ripening of the started fermented sausages was due to the activity of the starter cultures or to the action of meat endogenous enzymes. 相似文献
132.
Silvana Mattedi Pedro J. CarvalhoJoão A.P. Coutinho Víctor H. AlvarezMiguel Iglesias 《The Journal of Supercritical Fluids》2011,56(3):224-230
The use of ionic liquids for CO2 capture and natural gas sweetening is being object of intense research. Within the enormous group of existing ionic liquids, those based on conjugate bases of carboxylic acids seem to be particularly promising. This work addresses the study of the high pressure CO2 solubility (up to 80 MPa) in two protic ionic liquids, N-methyl-2-hydroxyethylammonium formate and N-methyl-2-hydroxyethylammonium acetate, in a wide range of temperatures (293-353 K). A thermodynamic model based on the Peng-Robinson equation of state with the Wong-Sandler mixing rule, using the NRTL model for the activity coefficients, was here adopted to describe and evaluate the thermodynamic consistency of the experimental data. Furthermore, the study of a ternary mixture of CO2 + CH4 + N-methyl-2-hydroxyethylammonium acetate was investigated showing a high selectivity from the IL towards these solutes. 相似文献
133.
Blends of polystyrene (PS) with polyester polyurethane elastomer (PU‐es) were compatibilized by addition of poly(styrene‐co‐maleic anhydride) (SMA) containing 7 wt % of maleic anhydride. Binary nonreactive (PS/PU‐es) blends, binary reactive (SMA/PU‐es) blends, and ternary reactive blends (PS/SMA/PU‐es) were prepared with 10 and 20 wt % of PU‐es. The maleic anhydride content in the ternary reactive blends was varied through addition of different SMA amounts from 0.5 to 5 wt %. Polyurethane in the blends was crosslinked by using dicumyl peroxide or sulfur to improve its mechanical properties. The experimental processing conditions, such as temperature and rotor speed in an internal mixer, were analyzed before blend preparation by processing the individual polymers, PS and SMA, and the PS/PU‐es nonreactive blend (90/10), to prevent the degradation of the polymer during melt mixing and to assure macroscopic homogeneity. The torque behavior during the mixture indicated a grafting copolymerization, which was responsible for the significant drop of the PU‐es domain size in the glassy matrix, as observed by scanning electronic microscopy (SEM). The miscibility of the glassy matrix, which was shown to be dependent on the composition and the phase behavior of ternary blends, became very complex as the SMA concentration increased, as concluded from dynamical–mechanical analysis. Blends containing 20 wt % of PU‐es presented an increase up to a factor of 2 in the deflection at break in relation to PS. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2297–2304, 2004 相似文献
134.
Marchetti R. Penco E. Armandillo E. Salvetti G. 《Quantum Electronics, IEEE Journal of》1982,18(2):170-173
The performance of a very compact TEA CO2 laser is described. The system utilizes simple circularly profiled electrodes and a single spark gap circuit for energizing both preioninizing and main discharges. An output power density in excess of 500 MW . 1-1has been measured. 相似文献
135.
136.
Silvana Martini María L. Herrera 《European Journal of Lipid Science and Technology》2008,110(2):172-182
The quality of shortenings, such as solid fat content (SFC) and texture, strongly depends on temperature fluctuations during storage and handling. The quality of a shortening might be affected not only by temperature fluctuations but also by its chemical composition and the presence of emulsifiers. The objective of this work was to investigate the effect of emulsifier addition and storage conditions on the texture, thermal behavior and SFC of low‐trans shortenings formulated with palm oil, palm kernel oil, and vegetable oils such as sunflower and soybean oils. Several conclusions can be drawn from this study: (a) The crystallization behavior of fat blends strongly depends on the type of emulsifier used and the chemical composition of the sample; (b) the addition of emulsifiers affects not only the type of crystals formed (fractionation) but also the amount of crystals obtained (enthalpy, SFC), inducing or delaying the crystallization process; (c) emulsifiers affect the texture of the crystalline structure formed by making it softer; (d) the storage conditions affect both the texture and the SFC of the materials. This study shows that samples that are highly super‐cooled during storage become harder while samples that are less super‐cooled become softer with storage conditions. 相似文献
137.
138.
Ettari R Bonaccorso C Micale N Heindl C Schirmeister T Calabrò ML Grasso S Zappalà M 《ChemMedChem》2011,6(7):1228-1237
Proteasome inhibition is a topic of great interest in anticancer research. The proteolytic activity of this multicatalytic complex relies on three subunits, β1, β2 and β5, containing a caspase-like, a trypsin-like and a chymotrypsin-like active site, respectively. Several studies have demonstrated that, of the three activities, the chymotrypsin-like activity was the most necessary for cell viability and protein processing. Thus, most efforts towards the development of proteasome inhibitors have focused on the selective inhibition of the β5 subunit active site. Herein, we report the design and synthesis of a series of conformationally constrained tripeptidyl vinyl sulfones were determined to be good inhibitors of the chymotrypsin-like activity of proteasome, with K(I) values in the sub-micromolar to micromolar range. These compounds were also tested against bovine pancreatic α-chymotrypsin and human cathepsin B and L, revealing a good selectivity for the target enzyme over these related enzymes. 相似文献
139.
Temponi Vdos S da Silva JB Alves MS Ribeiro A de Jesus Ribeiro Gomes de Pinho J Yamamoto CH Pinto MA Del-Vechio-Vieira G de Sousa OV 《International journal of molecular sciences》2012,13(3):3887-3899
The ethanol extract from Vernonia polyanthes leaves (EEVP) was investigated for antinociceptive and anti-inflammatory effects at the doses (p.o.) of 100, 200 and 400 mg/kg in animal models. The extract reduced the number of abdominal contortions by 16.75% and 31.44% at a dose of 200 and 400 mg/kg, respectively. The results obtained showed that EEVP exerted a significant antinociceptive effect in the two phases of formalin. The EEVP increased the reaction time on a hot plate at the doses of 100, 200 and 400 mg/kg after 90 min of treatment. The paw edema was reduced by EEVP at the doses of 100, 200 and 400 mg/kg after 4 h of application of carrageenan. Doses of 200 and 400 mg/kg, administered 4 h before the carrageenan injection, significantly reduced the exudate volume (29.25 and 45.74%, respectively) and leukocyte migration (18.19 and 27.95%, respectively). These results suggest that V. polyanthes can be an active source of substances with antinociceptive and anti-inflammatory activities. 相似文献
140.
Antonietta Ruggiero Sara Vitalini Nedda Burlini Silvana Bernasconi Marcello Iriti 《Food chemistry》2013
To improve the knowledge on the chemical diversity and complexity of grapevine, we investigated the plant sterol content of berry and seed tissues at pre-véraison and véraison stages in 2009 and 2010. We also assessed the effects of benzothiadiazole and chitosan elicitors on content of sterols in grapes and their levels in the corresponding experimental wines. β-Sitosterol was the most abundant component in berry tissues, in both growth stages and years, with the highest amounts in the flesh and skin at pre-véraison and véraison, respectively. Stigmasterol and campesterol were present in lower concentrations in both phenological stages and vintages. During the transition from pre-véraison to véraison, phytosterols decreased in all tissues, in both years, apart from stigmasterol in seeds. In addition, the results showed that the plant activators were more effective than conventional fungicides in rising the levels of sterols, particularly β-sitosterol, both in grapes and in microvinificates. 相似文献