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A first approach towards the development of geographical origin tracing models for North Moroccan olive oils based on triacylglycerols profiles
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54.
The controlled synthesis of narrowly distributed low molecular weight polymers with functionalization possibilities is of great industrial interests. Although living polymerization allows for control over polymer architecture, the production of low molecular weight polymers with low polydispersities via living polymerization systems is challenged by the use of large amounts of catalysts and broadening in molecular weight distribution. This review addresses the synthesis of narrowly distributed, functional, low molecular weight polyethylene and polyethylene mimics. The review is structured for quick identification of relevant systems for the production of specific polymer architectures with specific cost, efficiency, and safety concerns. 相似文献
55.
Gabriela Loscalzo Julia Scheel Jos Santiago Ibaez-Cabellos Eva García-Lopez Shailendra Gupta Jos Luis García-Gimenez Salvador Mena-Moll Alfredo Perales-Marín Jos Morales-Rosell 《International journal of molecular sciences》2022,23(1)
In a prospective study, 48 fetuses were evaluated with Doppler ultrasound after 34 weeks and classified, according to the cerebroplacental ratio (CPR) and estimated fetal weight (EFW), into fetuses with normal growth and fetuses with late-onset fetal growth restriction (LO-FGR). Overexpression of miRNAs from neonatal cord blood belonging to LO-FGR fetuses, was validated by real-time PCR. In addition, functional characterization of overexpressed miRNAs was performed by analyzing overrepresented pathways, gene ontologies, and prioritization of synergistically working miRNAs. Three miRNAs: miR-25-3p, miR-185-5p and miR-132-3p, were significantly overexpressed in cord blood of LO-FGR fetuses. Pathway and gene ontology analysis revealed over-representation of certain molecular pathways associated with cardiac development and neuron death. In addition, prioritization of synergistically working miRNAs highlighted the importance of miR-185-5p and miR-25-3p in cholesterol efflux and starvation responses associated with LO-FGR phenotypes. Evaluation of miR-25-3p; miR-132-3p and miR-185-5p might serve as molecular biomarkers for the diagnosis and management of LO-FGR; improving the understanding of its influence on adult disease. 相似文献
56.
David Betancur‐Ancona Santiago Gallegos‐Tintor Luis Chel‐Guerrero 《Journal of the science of food and agriculture》2004,84(10):1193-1201
The optimum extraction conditions for integral use of Phaseolus lunatus seed, in alkaline medium, are 1:6 (w/v) flour:water ratio, pH 11 and a 1 h extraction time. Three main fractions were produced under these conditions: starch; protein isolate and fibrous residue by‐product. The yield is 288.4 g kg?1 starch, 188.2 g kg?1 protein isolate and the remaining quantity, fibrous residue. The starch has 98.4% purity, a 75 °C gelatinization temperature and high syneresis even at high concentrations. It also has high viscosity, good stability and middle retrogradation during the heating–cooling cycle. The protein isolate contains 711.3 g kg?1 protein as well as 75.5 g lysine kg?1 protein, 10.1 g methionine kg?1 protein and 12.2 g tryptophan kg?1 protein. Its in vitro digestibility is 79% with a 2.5 c‐PER. The fibrous residue contains 63 g kg?1 of protein, 328.4 g kg?1 of crude fiber and 567.3 g kg?1 of NFE. Copyright © 2004 Society of Chemical Industry 相似文献
57.
Ultraviolet (UV)-C treatments are a promising technology for liquid food pasteurization as an alternative to heat treatments. However, the design of efficient UV reactors to reduce pertinent microorganisms and comply with current food safety goals is still an engineering challenge due to the low penetration depth of UV light in liquid foods with high UV absorbance and suspended particles, and the variations in the residence time of the product in the UV reactors. This review focuses on physical aspects of UV radiation related to the essential product and processing parameters for the design of UV reactors. The UV equipment available for liquid food processing is described and the main drawbacks and advantages are discussed. 相似文献
58.
David Sanz Luis Mata Santiago Cond��n Mar��a ��ngeles Sanz Pedro Razquin 《Food Analytical Methods》2011,4(2):212-220
Concerns regarding the presence of drug residues in foods include allergic reactions, toxicity, technological problems in
fermented products and the development of antibiotic resistance in human pathogens. The analysis of antimicrobial residues
in foods is generally carried out, in a first step, through microbiological screening tests. These tests commonly use Geobacillus stearothermophilus as target specie but show a low ability to detect quinolones. The goal of our study was to evaluate the performance of a
new microbiological test (Equinox) for detection of quinolone residues in muscle. The kit contains an ampoule with a standardized
number of freeze-dried Escherichia coli and must be diluted with a specific detection medium containing a redox indicator. Microbial growth will modify the redox
potential of the medium being observed through a colour change (from blue to brown/orange). Equinox limits of detection for
most of tested quinolones (enrofloxacin, norfloxacin, sarafloxacin, marbofloxacin, ciprofloxacin, danofloxacin and difloxacin)
were below or around maximum residue limit (MRL) UE and CCβ values obtained corresponded with the determined sensitivities.
In contrast, flumequine could not be detected at MRL UE levels. Moreover, Equinox displayed a low sensitivity to other antimicrobials.
Sensitivity data obtained in vitro were consistent when testing incurred muscle samples. Matrix constituents, test batch and
animal species did not affect the performance of the test. Equinox could be easily automated enabling a large numbers of simultaneous
analysis, and a photometric reading can be applied for a precise interpretation. The results obtained in this study prove
that Equinox is a useful tool when screening for quinolone residues or can be combined with other methods for screening of
unknown samples. 相似文献
59.
María Julia Spotti Martina J. Perduca Andrea Piagentini Liliana G. Santiago Amelia C. Rubiolo Carlos R. Carrara 《Food Hydrocolloids》2013
The effect of Maillard reaction on the mechanical properties of whey protein isolate (WPI) heat-induced gels was evaluated. WPI and dextran (15–25 kDa) conjugates were obtained by controlled dry heating during storage at 60 °C and 63% relative humidity for 2, 5 and 9 days. Changes in browning intensity and content of free amino groups were used to estimate the Maillard reaction. A decrease in free amino groups of WPI was observed when increasing polysaccharide concentration and reaction time. An increase in both a* and b* CIE Lab colour parameters indicated the development of a reddish-brown colour, typical of the Maillard reaction. Uniaxial compression and stress relaxation tests were performed to measure the mechanical properties of mixed and conjugate gels. Maillard reaction significantly modified the mechanical properties of WPI/DX gels, and even prevented fracture when conjugate gels were subjected to 80% deformation in uniaxial compression test. 相似文献
60.
Leonardo Queiroz de Souza Ana Dolores Santiago de Freitas Everardo Valadares de Sá Barretto Sampaio Patrícia Maia Moura R?mulo Sim?es Cezar Menezes 《Nutrient Cycling in Agroecosystems》2012,94(2-3):171-179
Despite the recognized importance of the process, estimates of the amount of nitrogen fixed by biological symbiosis in tropical dry forests are almost nonexistent. We estimated the nitrogen fixed annually by the leaves of trees and shrubs at sites regenerating for 16 and 38?years and in an old-growth dry forest using 15N abundance methodology. The total leaf biomass (1,824?C3,036?kg?ha?1) and nitrogen contents (62?C90?kg?ha?1) did not differ among the areas. In all of the areas, most of the leaf biomass belonged to legume plants, but the proportion of the N2-fixing legumes decreased with increasing regeneration time. In the 16-year regenerating area, almost all of the N was in the leaves of the N-fixing Mimosa tenuiflora plants, but fixation was absent or very low as it was in the N-fixing species present in the 38-year regenerating area. In the old-growth Caatinga, all of the N-fixing species (M. tenuiflora, Piptadenia stipulacea and Anadenanthera colubrina) had large proportions (47?C62?%) of their N derived from atmospheric N2, but the amount of fixed N (6?kg?ha?1) was a small proportion of the total leaf N because these plant species were a small part of the vegetation. The total input of biologically fixed N to the old-growth forest was similar in magnitude to an estimate made for a humid tropical forest in Amazonia. 相似文献