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191.
The effect of a flax seed (Linum usitatissimum) soaking on the development of rancidity in frozen mackerel (Scomber scombrus) was studied. Fresh mackerel fillets were soaked in an aqueous flax seed extract for 20 min and then kept frozen (?20 °C) for up to 7 months. A parallel experiment with non‐soaked fillets was carried out under the same conditions. The development of rancidity was measured by biochemical (free fatty acids, peroxides, conjugated dienes and trienes, secondary oxidation products, fluorescent and browning compounds and lipoxygenase activity) and sensory (general aspect, odour and colour) analyses. An inhibitory effect of the soaking treatment on rancidity development was observed according to the peroxide content and the formation of fluorescence and browning. A lower lipoxygenase activity was detected at 1 month in the soaked fillets; after this, no differences were obtained between either type of sample, whose activities at month 7 were negligible. According to the sensory analyses, non‐soaked fillets had fair quality at 1 month and were rejectable at 3 months, while the soaked ones were still of good quality at 1 month and rejectable at 5 months. According to the present results, soaking in an aqueous flax seed extract could be useful for inhibiting the development of rancidity in fatty fish fillets. Copyright © 2006 Society of Chemical Industry  相似文献   
192.
Pickling is one of the methods for preserving food. However, this term may refer to both types of products, that is, to those subjected to lactic acid fermentation and to marinated ones (acidified) that are usually produced by the addition of acetic acid. Various raw materials are subjected to lactic acid fermentation (vegetable and animal origin), which yields food products with high nutritional and dietary value. In many regions of the world, the process of lactic fermentation is also traditionally used to preserve fruiting bodies of edible mushrooms. Mushrooms are appreciated for their organoleptic qualities as well as the presence of many different bioactive substances exhibiting healing and health‐promoting properties. This article reviews the literature related to the use of lactic fermentation in the process of mushroom preservation. Particular attention has been paid to the aspects of the technological process and its impact on the quality and suitability of the final products. Moreover, research results concerning the influence of lactic fermentation on chemical and physical changes in fruiting bodies of edible fungi are also presented.  相似文献   
193.
Amyloid fibrils have been known for many years. Unfortunately, their fame stems from negative aspects related to amyloid diseases. Nevertheless, due to their properties, they can be used as interesting nanomaterials. Apart from their remarkable stability, amyloid fibrils may be regarded as a kind of a storage medium and as a source of active peptides. In many cases, their structure may guarantee a controlled and slow release of peptides in their active form; therefore, they can be used as a potential nanomaterial in drug delivery systems. In addition, amyloid fibrils display controllable stiffness, flexibility, and satisfactory mechanical strength. In addition, they can be modified and functionalized very easily. Understanding the structure and genesis of amyloid assemblies derived from a broad range of amyloidogenic proteins could help to better understand and use this unique material. One of the factors responsible for amyloid aggregation is the steric zipper. Here, we report the discovery of steric zipper-forming peptides in the sequence of the amyloidogenic protein, human cystatin C (HCC). The ability of short peptides derived from this fragment of HCC to form fibrillar structures with defined self-association characteristics and the factors influencing this aggregation are also presented in this paper.  相似文献   
194.
Ischemic heart disease (IHD) is among the leading causes of death in developed countries. Its pathological origin is traced back to coronary atherosclerosis, a lipid-driven immuno-inflammatory disease of the arteries that leads to multifocal plaque development. The primary clinical manifestation of IHD is acute myocardial infarction (AMI),) whose prognosis is ameliorated with optimal timing of revascularization. Paradoxically, myocardium re-perfusion can be detrimental because of ischemia-reperfusion injury (IRI), an oxidative-driven process that damages other organs. Amyloid-β (Aβ) plays a physiological role in the central nervous system (CNS). Alterations in its synthesis, concentration and clearance have been connected to several pathologies, such as Alzheimer’s disease (AD) and cerebral amyloid angiopathy (CAA). Aβ has been suggested to play a role in the pathogenesis of IHD and cerebral IRI. The purpose of this review is to summarize what is known about the pathological role of Aβ in the CNS; starting from this evidence, we will illustrate the role played by Aβ in the development of coronary atherosclerosis and its possible implications in the pathophysiology of IHD and myocardial IRI. Better elucidation of Aβ’s contribution to the molecular pathways underlying IHD and IRI could be of great help in developing new therapeutic strategies.  相似文献   
195.
Journal of Housing and the Built Environment - One of the largest problems in the real estate market analysis, which includes valuation, is determining the significance of individual property...  相似文献   
196.

Biomass waste contains an abundant source of energy that can be transformed into high-calorific fuel during intermediate pyrolysis, consequently reducing the use of fossil fuel resources. In the present study, medium density fibreboard (MDF), brewery spent grains (BSG) and post-extraction soybean meal (SM) were used to pyrolysis. Valorisation of these wastes via intermediate pyrolysis was carried out at a temperature of 773 K in a fixed-bed reactor under nitrogen atmosphere. The ultimate analysis showed that MDF char has offered the highest carbon content. Generally, chars obtained from these feedstocks were characterized by different internal microstructures. On the one hand, the surface of MDF char has exhibited pores with a regular pattern of small perpendicular blocks. On the other hand, irregular open spaces were detected in BSG and SM chars. The results of this investigation of the microstructure proved that the studied biomass wastes are perspective feedstocks to obtain high-value bioenergy products. Based on the enthalpy balance, it was concluded that the heating value of the pyrolysis gas was higher, the more endothermic pyrolysis process. The research hypothesis confirms that the higher the K2O/CaO ratio in the ash, the better biomass pyrolysis process was catalysed and as a result, less additional heat was required for pyrolysis. To carry out the pyrolysis of MDF, SM and BSG, additional heat input was required in the amount of 2016.8, 1467.9 and 881.1 kJ, respectively. It was found that 4–10% of the higher heating value of the raw materials was missing to achieve the self-sustaining energy of intermediate pyrolysis.

Graphical abstract
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197.
The aim of the study was to assess the physicochemical properties, texture, colour and sensory quality of organic yoghurts with regard to the milk treatment (raw milk obtained directly from organic farms, partially skimmed and heat‐treated in the laboratory vs organic milk purchased in the shop that was pasteurised in a dairy), production season and starter culture. The yoghurts produced on the basis of bulk milk obtained from farms during the spring/summer season proved to be of greater nutritional value and had higher content of bioactive whey proteins, except for β‐lactoglobulin, and lipophilic vitamins than retail milk.  相似文献   
198.
In the search for an effective strategy to overcome antimicrobial resistance, a series of new morpholine-containing 5-arylideneimidazolones differing within either the amine moiety or at position five of imidazolones was explored as potential antibiotic adjuvants against Gram-positive and Gram-negative bacteria. Compounds (7–23) were tested for oxacillin adjuvant properties in the Methicillin-susceptible S. aureus (MSSA) strain ATCC 25923 and Methicillin-resistant S. aureus MRSA 19449. Compounds 14–16 were tested additionally in combination with various antibiotics. Molecular modelling was performed to assess potential mechanism of action. Microdilution and real-time efflux (RTE) assays were carried out in strains of K. aerogenes to determine the potential of compounds 7–23 to block the multidrug efflux pump AcrAB-TolC. Drug-like properties were determined experimentally. Two compounds (10, 15) containing non-condensed aromatic rings, significantly reduced oxacillin MICs in MRSA 19449, while 15 additionally enhanced the effectiveness of ampicillin. Results of molecular modelling confirmed the interaction with the allosteric site of PBP2a as a probable MDR-reversing mechanism. In RTE, the compounds inhibited AcrAB-TolC even to 90% (19). The 4-phenylbenzylidene derivative (15) demonstrated significant MDR-reversal “dual action” for β-lactam antibiotics in MRSA and inhibited AcrAB-TolC in K. aerogenes. 15 displayed also satisfied solubility and safety towards CYP3A4 in vitro.  相似文献   
199.
200.
ABSTRACT

This work presents unique microstructure and thermal properties of the Fe55Ni20Cu5P10Si5B5 alloy produced by novel modification of the melt-spinning method, where two precursor alloys are simultaneously ejected i.e. Fe40Ni40P10Si5B5 and Fe70Cu10P10Si5B5, forming a composite ribbon. The investigation of melting the precursors by differential scanning calorimetry confirms the liquid miscibility of the Fe70Cu10P10Si5B5 alloy. The two-component melt-spun composite obtained from the two alloys is compared to the alloys produced from a homogeneous liquid. The electron microscopy, X-ray diffraction and differential scanning calorimetry show different microstructure of the composite in comparison with the traditionally melt-spun alloys and our results reveal that the composite alloy inherits the thermal properties of the precursors.

This paper is part of a Thematic Issue on The Crystallographic Aspects of Metallic Alloys.  相似文献   
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