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191.
In Finland, berries are part of the traditional diet significantly contributing to the intake of flavonoids and other phenolic compounds. Compositional data on phenolic compounds in berries has been rapidly accumulating and included in the national food composition database. Among the different bioactive substances in berries, phenolic compounds including flavonoids, tannins, and phenolic acids have received considerable interest due to their effects in food and health. A great amount of in vitro evidence exists showing that berry phenolics are powerful antioxidants. However, the antioxidant effect of berry phenolics is strongly dependent on the choice of berry raw material, as the antioxidant activity differs between the different phenolic constituents, including anthocyanins, ellagitannins, and proanthocyanidins. In foods, the antioxidant effect is also influenced by the structure of food. Tannin-containing berries exhibit antimicrobial properties against pathogenic bacteria, thus offering many new applications for food industry. Much of the interest in berry phenolics has focused on cranberries and both cultivated and wild blueberries, although also other berries including black currants, cloudberries, lingonberries, and red raspberries possess promising bioactivities that may have relevance to human health. Antioxidant activity of berry phenolics, in addition to other mechanisms, may contribute to human health, but the possible relationship remains yet to be scientifically substantiated.  相似文献   
192.
Brewers’ spent grain (BSG) is the main solid by‐product of the brewing process and is typically disposed of as cattle feed. In this study, BSG was evaluated as a substrate for the production of polyphenols and the lignin‐degrading enzyme laccase using fungal solid‐state fermentation by Trametes versicolor. Laccases are finding increasing applications in the food industry and polyphenols have benefits for human health. After 14 days of fermentation with T. versicolor, there was a 3.4‐fold increase in the extraction of total polyphenols compared with untreated BSG. Using BSG as the sole source of carbon and nitrogen, maximum laccase activity was achieved after seven days of treatment with an activity of 560 U/L. Based on these results, BSG is suggested to be a good lignocellulose waste material to produce value‐added products such as the enzyme laccase and polyphenols. Copyright © 2018 The Institute of Brewing & Distilling  相似文献   
193.
The yeast Dekkera/Brettanomyces bruxellensis can cause enormous economic losses in wine industry due to production of phenolic off-flavor compounds. D. bruxellensis is a distant relative of baker's yeast Saccharomyces cerevisiae. Nevertheless, these two yeasts are often found in the same habitats and share several food-related traits, such as production of high ethanol levels and ability to grow without oxygen. In some food products, like lambic beer, D. bruxellensis can importantly contribute to flavor development. We determined the 13.4 Mb genome sequence of the D. bruxellensis strain Y879 (CBS2499) and deduced the genetic background of several "food-relevant" properties and evolutionary history of this yeast. Surprisingly, we find that this yeast is phylogenetically distant to other food-related yeasts and most related to Pichia (Komagataella) pastoris, which is an aerobic poor ethanol producer. We further show that the D. bruxellensis genome does not contain an excess of lineage specific duplicated genes nor a horizontally transferred URA1 gene, two crucial events that promoted the evolution of the food relevant traits in the S. cerevisiae lineage. However, D. bruxellensis has several independently duplicated ADH and ADH-like genes, which are likely responsible for metabolism of alcohols, including ethanol, and also a range of aromatic compounds.  相似文献   
194.
Storage of maize products such as tortillas may cause starch retrogradation and lead to resistant starch (RS) formation. This study was carried out to determine if storage of maize tortillas under refrigerated conditions enhanced RS content and/or modified RS structure. Improved Costeño variety maize grain was nixtamalized and processed into tortillas which were stored for five and ten days at 5°C. Total resistant starch (TRS) and retrograded resistant starch (RRS or RS3) contents were determined on raw and nixtamalized maize grain and tortillas stored for zero, five and ten days. Differential scanning calorimetry (DSC), X‐ray diffraction (XRD) and near‐infrared (NIR) spectroscopy were use to evaluate structural changes in retrograded resistant starch isolated from each sample type. Total starch content was 67 ± 1.5% for all samples, TRS ranged from 3.3% in the raw grain at 7.2% in tortillas stored for ten days, while RRS starch content ranged from 0% in the raw grain to 3.2% in tortillas stored for ten days. DSC showed endothermic transitions corresponding to amylopectin and amylose retrogradation, at 31.9 and 139.7°C in RRS from tortillas stored for five days, and at 47.9 and 146°C in RRS from tortillas stored for ten days. These values agreed with the higher total RS content recorded after prolonged storage. XRD revealed a starch crystallinity of 13.7% in tortillas stored for five days and 15.3% in those stored for ten days. NIR spectroscopy analysis showed evidence of structural changes in polymeric order that were more pronounced in RRS of tortillas stored for ten days, due to increase in crystalline region.  相似文献   
195.
The sulfated polysaccharide obtained from a species of red microalga has proved to be a potent antiviral agent against various members of the herpes family. In the present study, we used microscopic Fourier transform infrared spectroscopy (FT-IR) to investigate differences between normal cells, those infected with herpes viruses, and infected cells treated with red microalgal polysaccharide. FT-IR enables the characterization of cell or tissue pathology based on characteristic molecular vibrational spectra of the cells. The advantage of microscopic FT-IR spectroscopy over conventional FT-IR spectroscopy is that it facilitates inspection of restricted regions of cell cultures or tissue. Our results showed significant spectral differences at early stages of infection between infected and noninfected cells, and between infected cells treated with the polysaccharide and those not treated. In infected cells, there was an impressive decrease in sugar content and a considerable increase in phosphate levels in conjunction with the infection progress. Our results also proved that sugars penetrated and accumulated inside cells treated with the red microalgal polysaccharide. These could have been sugar fragments of low molecular weight present in the polysaccharide solution, despite purification by dialysis. Such sugar accumulation might be responsible for a breakdown in the internal steps of the viral replication cycle.  相似文献   
196.
Objective: To investigate the attitudes of terminally ill individuals toward the legalization of euthanasia or physician-assisted suicide (PAS) and to identify those who would personally desire such a death. Design: In the Canadian National Palliative Care Survey, semistructured interviews were administered to 379 patients who were receiving palliative care for cancer. Patients who expressed a desire for physician-hastened death were followed prospectively. Main Outcome Measures: Attitudes toward the legalization of euthanasia or PAS were determined, as was the personal interest in receiving a hastened death. Demographic and clinical characteristics were also recorded, including a 22-item structured interview of symptoms and concerns. Results: There were 238 participants (62.8%) who believed that euthanasia and/or PAS should be legalized, and 151 (39.8%) who would consider making a future request for a physician-hastened death. However, only 22 (5.8%) reported that, if legally permissible, they would initiate such a request right away, in their current situations. This desire for hastened death was associated with lower religiosity (p = .010), reduced functional status (p = .024), a diagnosis of major depression (p  相似文献   
197.
Nowadays, the disposal of plastic waste is an issue of major concern worldwide because of its considerable volume and growth. An option to tackle this problem is to recycle this waste. This alternative reduces the quantity of net discards, conserves both material and energy and provides a comparatively simple way to make a substantial reduction in the overall volume of solid waste. The purpose of this study is to investigate an environmentally friendly approach about the influence of recycling different percentages of urban and rural plastic waste by adding them in a dry process on an asphalt mixture, through a comparative laboratory study. The resulting mixtures are analyzed considering their volumetric parameters and the values from diverse laboratory mechanical tests. The performance tests include, Marshall stability, Marshall quotient, indirect tensile strength, fracture energy, resilient modulus, permanent deformation and creep compliance, which were carried out on unmodified and modified hot asphalt mixtures. The obtained results are presented and discussed in this paper showing that the reuse of recycled plastics in asphalt mixtures is a viable alternative that contributes to the reduction of plastic wastes as well as the protection of the environment.  相似文献   
198.
The selective degradation of disease-associated microRNA is promising for the development of new therapeutic approaches. In this study, we engineered a series of bulge-loop-forming oligonucleotides conjugated with catalytic peptide [(LeuArg)2Gly]2 (BC–miRNases) capable of recognizing and destroying oncogenic miR-17 and miR-21. The principle behind the design of BC–miRNase is the cleavage of miRNA at a three-nucleotide bulge loop that forms in the central loop region, which is essential for the biological competence of miRNA. A thorough study of mono- and bis-BC–miRNases (containing one or two catalytic peptides, respectively) revealed that: (i) the sequence of miRNA bulge loops and neighbouring motifs are of fundamental importance for efficient miRNA cleavage (i.e., motifs containing repeating pyrimidine–A bonds are more susceptible to cleavage); (ii) the incorporation of the second catalytic peptide in the same molecular scaffold increases the potency of BC–miRNase, providing a complete degradation of miR-17 within 72 h; (iii) the synergetic co-operation of BC–miRNases with RNase H accelerates the rate of miRNA catalytic cleavage by both the conjugate and the enzyme. Such synergy allows the rapid destruction of constantly emerging miRNA to maintain sufficient knockdown and achieve a desired therapeutic effect.  相似文献   
199.

Abstract  

The gaseous products of photocatalytic oxidation (PCO) of acrylonitrile on sulphated P25 in concentrations from 10 to 100 ppm at 60 to 130 °C were CO2, HCN and HNCO. This photocatalyst showed disproportionally improved performance at higher temperature and longer retention times. The temperature-programmed oxidation (TPO) after PCO disclosed possible reaction routes.  相似文献   
200.
The results of studies on the oxidation of carbon black are represented. It was found that materials with different porosity can be obtained by varying the nature of an activating agent and the conditions of activation. A correlation of the sizes of carbon crystallites in the initial sample, the extent of their boundaries, and the rates of pyrocompaction and oxidation of these samples with the specific surface area of materials obtained upon activation was established.  相似文献   
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