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排序方式: 共有5556条查询结果,搜索用时 15 毫秒
1.
Yating Zhang Fuge Niu Xiaoming Zhang Zhengli Lu Yi Guo 《International Journal of Food Properties》2018,21(1):2239-2249
This study aimed to investigate the effect of limited hydrolysis on conformational and antioxidant properties of soy protein isolate-maltodextrin (SPI-Md) conjugates. Extrinsic fluorescence analysis showed unfolding of the protein molecule and exposure of hydrophobic groups in SPI-Md conjugate hydrolysates. Free amino acid analysis showed that, the contents of hydrophobic amino acids in SPI-Md conjugates increased after hydrolysis. The contents of leucine, isoleucine, phenylalanine increased from 0.32, 0.30 and 0.54 to 1.36, 1.86 and 2.60, respectively, when the hydrolysis degree (DH) gradually increased from 0% to 5.7%. The FT-IR spectrum showed that C = O absorption of the amide group formed by glycosylation continued unabated after limited hydrolysis (DH 2.9%). The glycated SPI products showed good reducing power and superior resistance to lipid oxidation (34%, 12 mg mL?1), whereas the limit hydrolysates (DH 2.9%) of SPI-Md conjugates showed more ef?cient radical-scavenging capacity (89.5%, at 12 mg mL?1) and iron-chelation activity (91.3%, at 12 mg mL?1). Results of this study indicated that, slight enzymatic hydrolysis (DH 0–2.9%) could help partially unfolding the globular structure of SPI-Md conjugates without deteriorating amide bonds and had a positive effect on their antioxidant properties. 相似文献
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Wan-Li Tan Dr. Chun Zhang Yang Li Dr. Kai Guo Dr. Xiao-Wei Gao Dr. Jun Wei Dr. Dong Yi Prof. Lin Pu Prof. Dr. Qin Wang 《ChemMedChem》2021,16(23):3569-3575
Forty samples of optically active falcarindiol analogues are synthesized by using the easily available C2 symmetric (R)- and (S)-1,1’-binaphth-2-ol (BINOL) in combination with Ti(OiPr)4, Zn powder and EtI. Their anticancer activities on Hccc-9810, HepG2, MDA-MB-231, Hela, MG-63 and H460 cells are assayed to elucidate their structure-activity relationships. These results showed that the falcarindiol analogue (3R,8S)- 2 i with the terminal double bond has the most potent anti-proliferation effect on Hccc-9810 cells with IC50 value of 0.46 μM. The falcarindiol analogue (3R,8S)- 2 i can induce obvious Hccc-9810 cell apoptosis in a concentration-dependent manner by Hoechst staining and flow cytometry analysis. The proposed mechanism suggests that the falcarindiol analogue (3R,8S)- 2 i increases LDH release and MDA content, and reduces the levels of SOD activity, which lead to the accumulation of oxidative stress and induce apoptosis in Hccc-9810 cells. 相似文献
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Paweł Lula Octavian Dospinescu Daniel Homocianu Napoleon-Alexandru Sireteanu 《计算机、材料和连续体(英文)》2021,66(3):2425-2443
Our primary research hypothesis stands on a simple idea: The evolution of top-rated publications on a particular theme depends heavily on the progress and maturity of related topics. And this even when there are no clear relations or some concepts appear to cease to exist and leave place for newer ones starting many years ago. We implemented our model based on Computer Science Ontology (CSO) and analyzed 44 years of publications. Then we derived the most important concepts related to Cloud Computing (CC) from the scientific collection offered by Clarivate Analytics. Our methodology includes data extraction using advanced web crawling techniques, data preparation, statistical data analysis, and graphical representations. We obtained related concepts after aggregating the scores using the Jaccard coefficient and CSO Ontology. Our article reveals the contribution of Cloud Computing topics in research papers in leading scientific journals and the relationships between the field of Cloud Computing and the interdependent subdivisions identified in the broader framework of Computer Science. 相似文献
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采用鲣鱼为原料,以蛋白质回收率为指标,酶解制备不同工艺条件的样品。通过测定其黄嘌呤氧化酶(XOD)抑制活性、ORAC值、分子质量分布图谱和总氨基酸含量,构建鲣鱼蛋白肽体外化学活性与其分子质量分布图谱、总氨基酸含量图谱之间的谱效关系。结合超高效液相-质谱联用(LC-MS/MS)方法研究其降尿酸肽和抗氧化肽的分布。研究表明,鲣鱼蛋白肽的XOD抑制活性与其ORAC值具有显著的相关性。由多肽分子质量<1ku所占含量的分布区段和脂肪族氨基酸的含量可初步预测鲣鱼蛋白肽的化学活性。质谱分析表明,纯化组分的质谱基峰图在不同时间段的信号强度与鲣鱼蛋白肽的降尿酸活性和抗氧化活性具有明显的相关性。 相似文献
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Alessandra Cristina Pedro Giselle Maria Maciel Valéria Rampazzo Ribeiro Charles Windson Isidoro Haminiuk 《International Journal of Food Science & Technology》2020,55(2):429-442
Catechins belong to the group of flavonoids. Numerous studies show that consuming foods rich in catechins such as vegetables, fruits and especially teas may decrease the risk of developing various diseases. Therefore, we present in this compilation a critical and detailed analysis of the works published in the last 6 years and a guide for the reader with the main analytical techniques of quantification, in vitro and in vivo biological activities, the mechanisms of action in the organism and the bioaccessibility in treating the gastrointestinal effects of catechins from different matrices. The information presented in this review is important for a broad understanding of benefits that catechins can bring to human health and can be taken as an example for the study of new matrices, new effects and possible forms of application, such as dietary supplements or functional food ingredients for health promotion and the reduced risk for developing diseases. 相似文献
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Identification of potential technologies for 1,4-Butanediol production using prospecting methodology
Ramon Geraldo Campos Silva Tatiana Felix Ferreira Élcio Ribeiro Borges 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2020,95(12):3057-3070
1,4-Butanediol (1,4-BDO) is a four-carbon diol used for industrial applications such as organic solvents, and the production of adhesives, fibers and polyurethanes. 1,4-BDO currently is produced through several petrochemical routes: hydrogenation of maleic anhydride, isomerization of propylene oxide, acetoxylation of butadiene, and the reaction between formaldehyde and acetylene. The current trends in 1,4-BDO production involve the utilization of renewable sources such as biomass. In this context, the present study aimed to identify promising technologies of 1,4-BDO production through prospecting methodology based on the analyses of patents and scientific article, describing the most relevant aspects of those emerging technologies. An increasing amount of 1,4-BDO production focused on biotechnological routes has been reported, with the US heavily involved in the development of new technologies. This study tracked three promising technologies which have potential for application in a biorefinery context because those processes involve (i) production of 1,4-BDO from sugars, classified herein as the biotechnological route; (ii) production of intermediates from sugar fermentation followed by catalytic conversion into 1,4-BDO, classified herein as the hybrid route, and (iii) furan/furfural conversion into 1,4-BDO. © 2020 Society of Chemical Industry 相似文献