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151.
Bukola M. Adenuga Magdalena Montowska 《Comprehensive Reviews in Food Science and Food Safety》2023,22(3):2112-2160
Despite the numerous studies on food safety and authenticity, especially for meat and meat products, not enough studies have been conducted focusing exclusively on game species and other unusual meat animals. As a result of the European horse scandal, the horse is currently the target of many meat authenticity studies. With this review, we aim to present various DNA-based methods that have been used by researchers to identify, detect, and quantify game, uncommon meat animals, and wildlife species. Polymerase chain reaction (PCR) is considered the standard method for DNA analysis in meat authenticity testing. However, in this paper, we present several other methods that may or may not involve the PCR technique. For this purpose, we systematically reviewed 131 articles selected according to various criteria such as target animal species, method of analysis, year of publication, and so forth. The result of our study shows the most studied game and uncommon meat species, PCR- and non-PCR-based methods for game meat analysis, and DNA-based methods in wildlife conservation. With this study, researchers can find detailed information about frequent game species used as adulterants for regular meat products and the DNA-based techniques to identify them. 相似文献
152.
Assessment of antimicrobial activity of coffee brewed in three different ways from different origins
Magdalena Mart��nez-Tom�� Antonia Ma Jim��nez-Monreal Laura Garc��a-Jim��nez Luis Almela Luis Garc��a-Diz Miguel Mariscal-Arcas M. Antonia Murcia 《European Food Research and Technology》2011,233(3):497-505
The antimicrobial effect against pathogens such as Staphylococcus aureus, Enterecoccus faecalis, Listeria monocytogenes, Pseudomonas aeruginosa, Escherichia coli and Salmonella choleraesius was determined in four types of coffee (Coffea arabica L. cv. Colombia, decaffeinated cv. Colombia, cv. Ethiopia and cv. Kenya). Coffee was seen to have significant activity against the growth of food spoilage bacteria. Among the Gram-positive bacteria, coffee was strongly active against S. aureus, moderately active against L. monocytogenes and had a slightly inhibitory effect against E. faecalis. However, coffee samples were found to be less active against Gram-negative bacteria. The results show that espresso Colombia coffee has better antimicrobial activity than filter and Italian coffee with significant differences (p?<?0.05). Taking into account the origin, there were significant differences (p?<?0.05) between Kenya and decaffeinated Colombia, on the one hand, and Ethiopia and Colombia coffee, on the other, the two last showing the highest antimicrobial activity. The antimicrobial activity of the coffee from different origins studied in this paper increased with concentration. Typical coffee compounds were also analysed, and only caffeic and chlorogenic acids showed any inhibitory effect against the growth of all the analysed bacteria. The antibacterial properties of coffee means that it has a promising potential as natural food ingredient to extend the shelf life of foods such as cake, cookies or biscuits, coffee flavoured with shakes, yoghurt. 相似文献
153.
Rita Głowacka Agata Górska Magdalena Wirkowska-Wojdyła Rafał Wołosiak Ewa Majewska Dorota Derewiaka 《International Journal of Food Science & Technology》2019,54(11):3008-3014
The content of bioactive compounds in spent coffee grounds (SGC) was studied. SGC were obtained from Coffea arabica beans of different roasting degrees (light and dark) and different geographical origins (Nicaragua, Columbia and Mexico) processed using four brewing methods (mocha, filtered, drip and infusion). The highest caffeine and chlorogenic acid contents were determined in filtered spent coffee extracts. All extracts of light roasted spent coffee grounds showed lower browning index levels in comparison to that from dark roasted spent coffee grounds. Generally, the highest content of total polyphenolic compounds and highest antioxidant capacity were determined in extracts prepared in drip. In conclusion, the results obtained in this study indicate that the spent coffee grounds produced of domestic levels, especially those obtained from filter coffeemaker, could be considered as a good source of natural antioxidants. 相似文献
154.
155.
People are an important source of pollution indoors, through activities such as cleaning, and also from “natural” emissions from breath and skin. This paper investigates natural emissions in high‐occupancy environments. Model simulations are performed for a school classroom during a typical summer in a polluted urban area. The results show that classroom occupants have a significant impact on indoor ozone, which increases from ~9 to ~20 ppb when the pupils leave for lunch and decreases to ~14 ppb when they return. The concentrations of 4‐OPA, formic acid, and acetic acid formed as oxidation products following skin emissions attained maximum concentrations of 0.8, 0.5, and 0.1 ppb, respectively, when pupils were present, increasing from near‐zero concentrations in their absence. For acetone, methanol, and ethanol from breath emissions, maximum concentrations were ~22.3, 6.6, and 21.5 ppb, respectively, compared to 7.4, 2.1, and 16.9 ppb in their absence. A rate of production analysis showed that occupancy reduced oxidant concentrations, while enhancing formation of nitrated organic compounds, owing to the chemistry that follows from increased aldehyde production. Occupancy also changes the peroxy radical composition, with those formed through isoprene oxidation becoming relatively more important, which also has consequences for subsequent oxidant concentrations. 相似文献
156.
157.
Oana Craciunescu Ana-Maria Seciu Vasile Sorin Manoiu Mihaela Trif Magdalena Moisei Alina Ioana Nicu 《Particulate Science and Technology》2019,37(6):753-759
Silver nanoparticles (AgNP) suspensions were biosynthesized by silver ions reduction in the presence of collagen, a nontoxic, organic polymer, intending to improve their medical use in periodontitis treatment. Spectrophotometric measurements showed a time- and concentration-dependent increase of AgNP formation in each suspension variant. Transmission electron microscopy revealed spherical morphology of AgNP in collagen and their mean diameter size was around 30?nm. The particle size distribution and zeta potential values of AgNP in collagen were determined by dynamic light scattering measurements. The surface charge of AgNP in collagen was positive, while commercial AgNP stabilized in citrate had negative surface charge. In vitro cytotoxicity testing of AgNP in collagen showed that they were biocompatible with human gingival fibroblasts in a wider range of concentrations than commercial nanoparticles. The antibacterial activity of AgNP in collagen against two pathogenic strains present in the periodontal pocket was dose-dependent and higher than that of AgNP in citrate. All these results demonstrated that AgNP prepared in collagen gel had improved properties, like small diameter, positive surface charge, high biocompatibility in human gingival fibroblasts, efficiency against bacterial growth and, thus, better therapeutic potential in periodontal disease treatment. 相似文献
158.
The bias against women in academia is a documented phenomenon that has had detrimental consequences, not only for women, but also for the quality of science. First, gender bias in academia affects female scientists, resulting in their underrepresentation in academic institutions, particularly in higher ranks. The second type of gender bias in science relates to some findings applying only to male participants, which produces biased knowledge. Here, we identify a third potentially powerful source of gender bias in academia: the bias against research on gender bias. In a bibliometric investigation covering a broad range of social sciences, we analyzed published articles on gender bias and race bias and established that articles on gender bias are funded less often and published in journals with a lower Impact Factor than articles on comparable instances of social discrimination. This result suggests the possibility of an underappreciation of the phenomenon of gender bias and related research within the academic community. Addressing this meta-bias is crucial for the further examination of gender inequality, which severely affects many women across the world. 相似文献
159.
Chuangang Hu Yi Lin John W. Connell Hui‐Ming Cheng Yury Gogotsi Maria‐Magdalena Titirici Liming Dai 《Advanced materials (Deerfield Beach, Fla.)》2019,31(13)
Owing to their high earth‐abundance, eco‐friendliness, high electrical conductivity, large surface area, structure tunability at the atomic/morphological levels, and excellent stability in harsh conditions, carbon‐based metal‐free materials have become promising advanced electrode materials for high‐performance pseudocapacitors and metal–air batteries. Furthermore, carbon‐based nanomaterials with well‐defined structures can function as green catalysts because of their efficiency in advanced oxidation processes to remove organics in air or from water, which reduces the cost for air/water purification and avoids cross‐contamination by eliminating the release of heavy metals/metal ions. Here, the research and development of carbon‐based catalysts in supercapacitors and batteries for clean energy storage as well as in air/water treatments for environmental remediation are reviewed. The related mechanistic understanding and design principles of carbon‐based metal‐free catalysts are illustrated, along with the challenges and perspectives in this emerging field. 相似文献
160.
Mrówka Jan Kosydar Robert Gackowski Mariusz Gurgul Jacek Lityńska-Dobrzyńska Lidia Handke Bartosz Drelinkiewicz Alicja Hasik Magdalena 《Journal of Materials Science》2022,57(26):12463-12482
Journal of Materials Science - Cross-linking of poly(hydromethylsiloxane) (PHMS) with 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane (D4Vi) in water-in-oil high internal phase emulsion... 相似文献