Selective MMP inhibitors : Eleven α‐sulfonylphosphonates were synthesized and tested as MMP inhibitors. The IC50 values for most of them are in the nanomolar range against MMP‐2, ‐8, ‐13, and ‐14, with an interesting selectivity profile versus MMP‐9.
Delayed failure and creep behavior of high-purity Si3N4 sintered without additives with a mean grain size of 1 μm has been measured at 1400°C. Lifetime under 300 MPa was >240 h, which showed good agreement with the value predicted in our previous report. Creep strain rate ranged from 1 × 10−5 to 3 × 10−5 h−1 between 200 and 360 MPa. These values demonstrate the excellent potential of high-purity Si3N4 materials for structural application up to 1400°C. 相似文献
A method based on reversed-phase high-performance liquid chromatography with fluorescence detector has been developed for the determination of tocopherols in vegetable oils. Oils were diluted in acetonitrile/tetrahydrofuran (THF) and injected directly onto HyPurity C18 column. Methanol and THF (90:10) mixture was used as a mobile phase. Tocopherols were detected by fluorescence detector. The method had good limit of detection (LOD) (7 ng/g for α-tocopherol and 6 ng/g for β-, γ- and δ-tocopherols) and reproducibility (CV% < 2.8%). 相似文献
The distribution of aflatoxin M1 (AFM1) has been investigated in samples of whey, curd and a typical hard and long maturing cheese like Grana Padano (ripened for twelve months), produced with naturally contaminated milk in a range of 30–98 ng AFM1/kg. AFM1 determinations were carried out on 25 samples of each product by reverse-phase HPLC and fluorescence detection with post-column derivatisation, after a preliminary C18-SPE clean-up. Experimental results show that, in comparison to milk, AFM1 concentration levels increased both in curd (3-fold) and in long maturing cheese (4.5-fold), while AFM1 occurrence in whey decreased by 40%. 相似文献
The present study focused on the application of pulsed electric fields (PEF) as an innovative pre-treatment technique to improve the recovery of polyphenols from two food by-products, cocoa bean shell (CBS) and coffee silver skin (CS). The effect of the different operating parameters on the extraction of polyphenols was optimised using the response surface methodology statistical approach. The optimised methodology was compared with conventional extraction and applied to several CBS and CS samples to classify the samples according to origin, variety and industrial treatment. PEF-assisted extraction had higher (approximately 20%) recovery yields of polyphenols and methylxanthines than conventional extraction. Finally, the results highlighted that the composition of bioactive compounds from different extracts of CBS and CS and their antioxidant properties depended on the origin, variety and industrial processing of the raw material. These by-products may be a promising source of natural compounds, with potential applications on food and health sectors. 相似文献
Microwave-assisted sample digestion and inductively coupled plasma-mass spectrometry (ICP-MS) were considered for exploring major and trace elements in the Mediterranean Sepia ink. The present work aims to (a) fully validate the employed ICP-MS method and compare the Hg determinations by ICP-MS with those obtained by a direct mercury analyzer (DMA) and (b) interpret quantitative data by chemometrics and perform a risk/benefit analysis for assessing the quality/safety of Sepia ink. DMA gave Hg determinations similar to the ICP-MS counterpart (p > 0.05), confirming its reliability for food analysis. Sepia ink demonstrated to be both a reservoir of “healthy” elements and a sink of potential toxic metals. In fact, a good contribution of major and essential trace metals to the established RDAs was revealed, and, at the same time, potentially toxic elements showed to accumulate depending upon the environmental conditions, although not representing a risk for human consumers. 相似文献
This article is a critical overview of recent contributions on the dietary corrections and the foods that have been claimed to delay or hinder the onset of diabetic nephropathy (DN) and its progression to end-stage renal disease. Innovative dietary and behavioral approaches to the prevention and therapy of DN appear to be the most captivating in consideration of the rather well-established protocols for glucose and blood pressure control in use. In addition to restricted caloric intake to contrast obesity and the metabolic syndrome, adjustments in the patient's macronutrients intake, and in particular some degree of reduction in protein, have been long considered in the prevention of DN progression. More recently, the focus has shifted to the source of proteins and the content of glycotoxins in the diet as well as to the role of specific micronutrients. Few clinical trials have specifically addressed the role of those micronutrients associated with diet proteins that show the most protective effect against DN. Research on clinical outcome and mechanisms of action of such micronutrients appears the most promising in order to develop both effective intervention on nutritional education of the patient and selection of functional foods capable of contrasting the onset and progression of DN. 相似文献
Lactobacillus plantarum LB1 and Lactobacillus rossiae LB5, isolated from wheat germ and selected based on the kinetics of acidification, were used as starters for the manufacture
of sourdough fermented wheat germ. A bread containing sourdough fermented wheat germ as an ingredient (SFWGB) was compared
to breads made with (raw wheat germ bread, RWGB) or without (wheat flour bread, WFB) raw wheat germ. The higher concentration
of free amino acids mainly differentiated SFWGB from WFB and RWGB. The in vitro protein digestibility of WFB was the highest,
even if sourdough fermentation of wheat germ attenuated the difference. Phytase and antioxidant activities of SFWGB were highest.
The specific volume and cell-total areas were also the highest for SFWGB. As determined by texture profile analysis, the values
of hardness, resilience and fracturability of breads containing wheat germ were lower than those found in WFB. The crust lightness
showed a decrease from WFB to SFWGB. As determined by sensory analysis, SFWGB had mainly acid taste and flavour and resulted
more salty. Sourdough fermented wheat germ is an ingredient able to enhance nutritional, texture and sensory properties of
bread. 相似文献
The use of two recently developed diglycolamide-based extractants for the co-separation of trivalent actinides (An(III)) and lanthanides (Ln(III)) is described and compared to the well-known extractant TODGA (N,N,N’,N’-tetraoctyl diglycolamide). The addition of one or two methyl groups to the central methylene carbon atoms of the TODGA molecule leads to a reduction of the extraction efficiency for An(III) and Ln(III). This is attributed to a lower complex formation constant, which was proven by Time-Resolved Laser Fluorescence Spectroscopy (TRLFS). Conditional stability constants were determined by solvent extraction and TRLFS. The reduction in extraction efficiency leads to overall reduced distribution ratios of all tested metal ions, including Sr(II). The reduced Sr(II) extraction is beneficial as a co-extraction in a solvent extraction process could be avoided, while an efficient extraction of the desired An(III) and Ln(III) is still achieved. Furthermore, this might be a benefit, as the stripping behavior might be improved, even at moderate nitric acid concentrations. The slightly higher affinity of the diglycolamides towards Eu(III) over Am(III) is represented by all ligands, although the selectivity is rather low. This results in promising extraction properties of the modified diglycolamides towards the development of continuous solvent extraction processes. 相似文献