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951.
Chiara Montanari Eleonora Bargossi Rosalba Lanciotti Fabio Chinnici Fausto Gardini Giulia Tabanelli 《LWT》2014
Pandoro is a traditional Italian sweet-leavened baked product, usually consumed at Christmas. It is manufactured according to specific procedures and preparation starts from a sourdough called ‘‘madre’’ (mother sponge) continuously refreshed. This sourdough is the result of a complex microbial association including yeasts and lactic acid bacteria (LAB) and its use can improve sensory quality and shelf-life of the resulting products. The aim of this work was to evaluate the effect of the use of two different sourdoughs matured at different temperature (13 and 19 °C) on some metabolites, which can affect the organoleptic characteristics of Pandoro. Different samples, taken throughout the 19 h of process, were analysed for the determination of yeast and LAB counts, pH, aw, carbohydrates, organic acids content and volatile profile. The results showed that, at the end of fermentation process, the sourdough propagated at 19 °C reached lower pH values than that at 13 °C. This was probably due to higher LAB counts (1 log unit higher), resulting also in higher lactic acid concentration and faster sugars depletion. On the contrary, temperature of dough during maturation did not affected yeast concentrations. Different production processes strongly affected also the volatile profile, both of sourdough at the end of fermentation and of the final products. 相似文献
952.
Aldo Corsetti Ombretta Massitti Fabio Minervini Patrick F. Fox Marco Gobbetti 《Food Biotechnology》2003,17(3):183-192
The aim of this work was to produce caseinophosphopeptides (CPPs) from Na-caseinates prepared from the milk of six species (bovine, sheep, goat, pig, buffalo, human) hydrolyzed by a partially purified proteinase from Lactobacillus helveticus PR4 and to characterize the CPP preparations by RP-FPLC (reversed-phase fast-protein liquid chromatography) and for calcium solubilizing/binding activity. The yield of CPPs ranged from 0.60 to 1.86% of the original proteins. The calcium-solubilizing activity varied from 2.5 (human CPPs) to 11.4 (buffalo CPPs) mg Ca2+ mg-1 CPP. Moreover, minor differences in calcium-binding ability between the CPP from different species were observed. This work showed that CPPs with different calcium-solubilizing activity can be produced from various Na-caseinates by a Lb. helveticus proteinase. Milks having casein-fractions with similar amino acid sequences (e.g., sheep and goat), showed CPPs with the same activity. The data generated in this study show the potential of different caseins to yield CPPs and may help in the selection of milk for the production of functional foods enriched in CPPs. 相似文献
953.
954.
Alice De Palo Dijana Draca Maria Grazia Murrali Stefano Zacchini Guido Pampaloni Sanja Mijatovic Danijela Maksimovic-Ivanic Fabio Marchetti 《International journal of molecular sciences》2021,22(14)
Piano-stool iridium complexes based on the pentamethylcyclopentadienyl ligand (Cp*) have been intensively investigated as anticancer drug candidates and hold much promise in this setting. A systematic study aimed at outlining the effect of Cp* mono-derivatization on the antiproliferative activity is presented here. Thus, the dinuclear complexes [Ir(η5-C5Me4R)Cl(μ-Cl)]2 (R = Me, 1a; R = H, 1b; R = Pr, 1c; R = 4-C6H4F, 1d; R = 4-C6H4OH, 1e), their 2-phenylpyridyl mononuclear derivatives [Ir(η5-C5Me4R)(kN,kCPhPy)Cl] (2a–d), and the dimethylsulfoxide complex [Ir{η5-C5Me4(4-C6H4OH)}Cl2(κS-Me2S=O)] (3) were synthesized, structurally characterized, and assessed for their cytotoxicity towards a panel of six human and rodent cancer cell lines (mouse melanoma, B16; rat glioma, C6; breast adenocarcinoma, MCF-7; colorectal carcinoma, SW620 and HCT116; ovarian carcinoma, A2780) and one primary, human fetal lung fibroblast cell line (MRC5). Complexes 2b (R = H) and 2d (4-C6H4F) emerged as the most active ones and were selected for further investigation. They did not affect the viability of primary mouse peritoneal cells, and their tumoricidal action arises from the combined influence on cellular proliferation, apoptosis and senescence. The latter is triggered by mitochondrial failure and production of reactive oxygen and nitrogen species. 相似文献
955.
Fabio Frustaci Stefania Perri Marco Lanuzza Pasquale Corsonello 《International Journal of Circuit Theory and Applications》2012,40(3):237-246
A new fast low‐power single‐clock‐cycle binary comparator is presented. High speed is assured by using parallel‐prefix architecture, whereas low power is guaranteed by reducing the switching activities of the internal nodes. When implemented with the ST 90 nm 1 V CMOS technology, the proposed circuit exhibits a 4.5 GHz maximum running frequency and 0.77µW/ MHz energy dissipation. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
956.
In this work, the effects on the volatile profile of the pre-fermentative substitution of SO2 with lysozyme and oenological tannins were studied in white wines. At the same time, in order to understand the changes of volatile compounds in SO2-free wines, the evolution of volatiles was evaluated over 1 year of storage in bottles. For this purpose, a number of laboratory scale fermentations of SauvignonBlanc musts were carried out and the effects of three variables (SO2, lysozyme and oenological tannins) were investigated by means of GC–MS analysis. Results showed that the replacement of SO2 with lysozyme and oenological tannins influenced the volatile composition of wines at the end of the alcoholic fermentation. Wines fermented with SO2 showed higher total alcohol amounts, while the presence of oenological tannins augmented the level of esters. The presence of SO2 influenced also the alcohols and esters profiles of wines during bottle storage. Moreover, the presence of oenological tannins displayed a positive role in maintaining the amounts of esters over certain levels in wine stored for 1 year, likely due to their oxygen scavenging ability. By contrast, acids were less affected by the investigated adjuvants both at the end of the alcoholic fermentation and during the storage time. 相似文献
957.
Oskar Larsson Ivanov Dániel Honfi Fabio Santandrea Håkan Stripple 《Structure and Infrastructure Engineering》2019,15(6):711-724
The construction and usage of transport infrastructure are major causes of greenhouse gas emissions and energy consumption. The effects of resource consumption and pollutant emissions are often quantified through Life Cycle Assessment (LCA) models. All decisions made in infrastructure projects during the whole life cycle are afflicted by uncertainty, e.g. physical properties of materials or amount of pollutants emitted by certain processes. The pervasive role of uncertainty is reflected in LCA models, which therefore should consider uncertainty from various sources and provide a sound quantification of their effects. The aim of the work presented in this paper is to give an overview of different sources of uncertainty in LCA of infrastructure projects and to describe systematic methods to evaluate their influence on the results. The possibility of including uncertainty in a LCA-tool for infrastructure is presented, studying the sensitivity of the model output to the input parameters and two alternative approaches for propagation of uncertainty using two case studies. It is shown that, besides the influence of uncertainty in emission factors, other inputs such as material amounts and service life could contribute significantly to the variability of model output and has to be considered if reliable results are sought. 相似文献
958.
Franciele M. Pelissari Fabio Yamashita Maria Victoria E. Grossmann 《International Journal of Food Science & Technology》2011,46(4):702-710
Despite the increased use of extrusion technology in the production of biodegradable films, a better understanding of its effects on the several biopolymers is required. Therefore, the influence of extrusion temperature (120, 130 and 140 °C) and screw speed (25, 35 and 45 r.p.m.) on the properties of an active film formulated with starch, chitosan and oregano essential oil was investigated. Mechanical and barrier properties, apparent opacity and blow‐up ratio (BUR) of films were determined. The increase in screw speed had a positive effect on BUR and water vapour permeability (WVP) and a negative effect on opacity, tensile strength and elongation at break of the films. Low die temperatures resulted in decreased tensile strength, elongation at break, Young’s modulus and WVP of the films. Sorption isotherms of films were directly influenced by the extrusion conditions and films produced at 130 °C and 35 r.p.m. were less hydrophilic. 相似文献
959.
960.