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吡喃酮型花色苷衍生物的制备、光谱特性及抗氧化活性研究 被引量:4
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作者 吴闹 王静祎 +3 位作者 江甜 李书艺 祝振洲 何静仁 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2017年第7期2120-2127,共8页
吡喃酮型花色苷衍生物是一类具有非氧鎓离子结构和内酯型吡喃环结构的新型多酚类化合物。本研究以植物花色苷为原料,通过羧基吡喃花色苷形成及微氧化等两步反应法,结合柱色谱分离纯化技术,制备高纯度的吡喃酮花色苷衍生物A(Oxovitisin A... 吡喃酮型花色苷衍生物是一类具有非氧鎓离子结构和内酯型吡喃环结构的新型多酚类化合物。本研究以植物花色苷为原料,通过羧基吡喃花色苷形成及微氧化等两步反应法,结合柱色谱分离纯化技术,制备高纯度的吡喃酮花色苷衍生物A(Oxovitisin A)标准品;高效液相色谱-光电二极管阵列检测器-串联质谱法(HPLC-DAD-ESI-MS/MS)分析鉴定出纯化后反应产物Oxovitisin A的纯度达99%以上。利用荧光光谱仪、紫外可见光谱仪及超微弱化学发光光谱仪研究了Oxovitisin A及其前体物质花色苷(锦葵素-3-葡萄糖苷,Mv-3-gluc)与羧基吡喃花色苷A(Vitisin A))的光谱特性、色泽稳定性及抗氧化活性。结果表明:Oxovitisin A在440nm激发波长下有最大荧光峰,最大发射波长490nm,而具有氧鎓离子结构的两种前体物质无荧光特性。紫外光谱结合LAB色泽空间表征参数显示Oxovitisin A在不同pH值条件下具有不同的结构稳定性和色泽稳定性。Mv-3-gluc,VitisinA和Oxovitisin A在不同体系中均表现出良好的抗氧化活性,清除超氧阴离子自由基的IC50值分别为71.4,30.7和19μg·mL-1(抗坏血酸28μg·mL-1),清除羟自由基的IC50值分别为1.68,3.524,2.854μg·mL-1(抗坏血酸8.441μg·mL-1),对双氧水清除率的IC50值分别为1.311,0.4098和0.288μg·mL-1(抗坏血酸3.265μg·mL-1),表明Oxovitisin A清除自由基和抗氧化的能力均高于反应前体物Mv-3-gluc和VitisinA及抗坏血酸。 展开更多
关键词 吡喃酮花色苷衍生物 Oxovitisin A HPLC-MS/MS分析 光谱特性 抗氧化
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花色苷稳态化技术研究进展及应用前景
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作者 王二雷 黄佳莹 +1 位作者 段海章 徐彩娜 《食品工业科技》 CAS 北大核心 2024年第18期394-403,共10页
花色苷,即花青素糖苷形式,是重要的呈色化合物,具有多种生物活性,如抗氧化、抗癌、预防心血管疾病等。但由于花色苷稳定性差,在加工及贮藏过程中易降解和失活,从而限制了花色苷的应用及其功效的发挥。为进一步提高花色苷的稳定性,扩大... 花色苷,即花青素糖苷形式,是重要的呈色化合物,具有多种生物活性,如抗氧化、抗癌、预防心血管疾病等。但由于花色苷稳定性差,在加工及贮藏过程中易降解和失活,从而限制了花色苷的应用及其功效的发挥。为进一步提高花色苷的稳定性,扩大花色苷的应用潜力,本文主要介绍了近年来花色苷多种稳态化技术,如酰基化、酯基化、吡喃化、辅色、微胶囊化、纳米脂质体、纳米乳液、水凝胶等技术,概述了稳态化花色苷作为食品添加剂、着色剂、新鲜度指示剂、染料敏化剂等在多个领域中的应用现状和前景,旨在为后期大规模开发花色苷产品提供参考依据。 展开更多
关键词 花色 吡喃花色 稳定性 微胶囊 脂质体
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Studies on the Karyotype of Three Species in the Genus Orius Wolff (Hemiptera:Anthocoridae) 被引量:2
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作者 王义平 卜文俊 +1 位作者 张虎芳 吴鸿 《Entomotaxonomia》 CSCD 北大核心 2007年第3期205-208,共4页
Karyotype of 3 species of the genus Orius Wolff were firstly studied using the Giemsa staining and squashing slides method in male germ cell. It is reported that number of chromosome and system of sex chromosome of ha... Karyotype of 3 species of the genus Orius Wolff were firstly studied using the Giemsa staining and squashing slides method in male germ cell. It is reported that number of chromosome and system of sex chromosome of haploid chromosome complement of these species is n=11A+X (Y) in the first meiotic stage. However, the behavior of chromosomes among the species are different distinctly, thus cytotaxonomic character can be adopted to the identification among the three species. 展开更多
关键词 HEMIPTERA ANTHOCORIDAE ORIUS CHROMOSOME KARYOTYPE
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膨化食品的分类及其标准要素
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作者 徐元凤 《监督与选择》 2004年第4期A013-A013,共1页
膨化食品是一种采用膨化工艺制成的体积明显增大,且具有一定酥松度的食品。比如深受人们喜欢的炸薯片、虾球、蚱条、米饼、爆米花等。近年来在膨化食品中尤其以膨化小食品发展最为迅速,美国、日本以及欧洲和东南亚许多著名的膨化食品... 膨化食品是一种采用膨化工艺制成的体积明显增大,且具有一定酥松度的食品。比如深受人们喜欢的炸薯片、虾球、蚱条、米饼、爆米花等。近年来在膨化食品中尤其以膨化小食品发展最为迅速,美国、日本以及欧洲和东南亚许多著名的膨化食品生产企业都纷纷到我国来投资建厂。随着中国市场的日益扩大,人们的生活水平提高。 展开更多
关键词 分类 标准 非油脂膨化食品 色泽 直接挤压 花色型 滋味 形态
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说梅(散文)
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作者 周咏 《云南林业》 1999年第5期28-28,共1页
关键词 照水梅 宫粉 梅花 生长姿态 花色 内山完造 经济价值 花梅 武昌东湖 观赏价值
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Digital Jacquard Fabric Design in Colorful Mode 被引量:3
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作者 周赳 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期98-101,共4页
Digital image design is one of advanced technique in textile design. The investigation into digital Jacquard textile design in the colorful mode is one form of research in digital Jacquard fabric design, which aimed a... Digital image design is one of advanced technique in textile design. The investigation into digital Jacquard textile design in the colorful mode is one form of research in digital Jacquard fabric design, which aimed at expanding past and present jacquard design and production methods towards innovative ends. In this paper, the design principles and design methods for unconventional digital Jacquard fabric design in colorful mode have been analyzed based on the new technologies and computer applied color theory. The results of this study will enhance further research in the area of digital textile. 展开更多
关键词 digital textile Jacquard fabric colorful mode TRUE-COLOR shadow weaves.
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Timber Trucking Characteristics in Greece
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作者 Evangelos Karagiannis Petros A. Tsioras Ploutarchos Kararizos 《Journal of Environmental Science and Engineering(B)》 2012年第9期1079-1086,共8页
Wood transportation begins from the landing or the forest road where the processed wood assortments are placed, they are loaded on trucks and then transported to the wood-working industry and/or the consumption center... Wood transportation begins from the landing or the forest road where the processed wood assortments are placed, they are loaded on trucks and then transported to the wood-working industry and/or the consumption centers. Wood transportation in Greece is carried out, almost exclusively, by trucks. The aim of this study is to analyze the evolution of timber trucking in Greece through the analysis of wood transportation waybills. A total of 1,471 waybills have been collected and analyzed that cover the period 1981-2008 from nine of the most productive and representative forest districts in Greece, in terms of timber production. The final dataset included information on the type and technical characteristics of truck types, the transported wood quantities and haulage distances. Furthermore, data on the wood transportation cost for the year 2010 have been collected and analyzed. According to the results, the number of two-axle trucks that dominated in the 1980s is reducing rapidly, mostly to the benefit of larger three-axle and four-axle trucks. More than three quarters (77%) of wood transportation is conducted in the period June-October. Mean vehicle load per vehicle type differs between conifer and broadleaved species from 7.1% up to 23.9%. Transportation of stacked wood with semitrailers is conducted with overloaded trucks, which could entail serious problems for public safety and the condition of road network. New design standards will enhance serviceability of the wood transportation routes and environmental protection. 展开更多
关键词 Wood transportation trucks permissible truck load season of wood transportation Greece.
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Regulation of Anthocyanin during Storage Root Development Stage in Sweet Potato(Ipomoea batatas(L.) Lam.)
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作者 Fuyun HOU Aixian LI +4 位作者 Haiyan ZHANG Shunxu DONG Beitao XIE Liming ZHANG Qingmei WANG 《Agricultural Science & Technology》 CAS 2016年第6期1376-1378,1474,共4页
Anthocyanin accumulation during storage root development in purple-fleshed sweet potato was analyzed by detection of anthocyanin concentration, accumulation rate and the expression pattern of anthocyanin biosynthetic ... Anthocyanin accumulation during storage root development in purple-fleshed sweet potato was analyzed by detection of anthocyanin concentration, accumulation rate and the expression pattern of anthocyanin biosynthetic genes by semi-quantitative RT-PCR. Anthocyanin concentration in sweet potato cvs Jishu 18 and Ayamurasaki increased steadily during storage root development stage. The accumulation rate in two genotypes peaked at 50 to 65 d after transplanting, and then declined rapidly. During storage root development of Ayamurasaki, the anthocyanin biosynthesis gene, IbCHS, was constitutively expressed, the genes IbF3H, IbDFR, IbANS were induced steadily, reaching a maximum at the later stage of root thickening, and IbPAL steadily decreased. Therefore, the mechanism of anthocyanin accumulation differed between the two cultivars, and anthocyanin biosynthesis was regulated through regulation of its synthetic enzymes. 展开更多
关键词 Ipomoea Lam anthocyanin sweet potato Sweet purple biosynthesis enzymes steadily
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Safflower yellow injection combined with conventional therapy in treating unstable angina pectoris:a meta-analysis 被引量:20
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作者 Dezhao Kong Wei Xia +4 位作者 Zhe Zhang Lei Xiao Dongchao Yuan Yue Liu Guanlin Yang 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2013年第5期553-561,共9页
OBJECTIVE: To evaluate the clinical efficacy of safflower yellow injection combined with conventional therapy in treating unstable angina pectoris.METHODS: We searched online databases: Chinese journal full-text da... OBJECTIVE: To evaluate the clinical efficacy of safflower yellow injection combined with conventional therapy in treating unstable angina pectoris.METHODS: We searched online databases: Chinese journal full-text database, China National Knowledge Infrastructure, Wanfang database, Chinese journal full-text database, Pubmed, ScienceDirect,Embase, and the Cochrane Library with manual-screening of relevant literature. Eligible randomized controlled trials(RCT) on angina pectoris were included. We conducted meta-analysis using the RevMan 5.1 software from The Cochrane Collaboration. We treated the relief rate of angina symptoms and electrocardiograph(ECG) as evaluation.RESULTS: Seven articles, including in 1134 patients, were enrolled after the evaluation. Therewas no significant heterogeneity among the studies(χ2=1.08, df=6, P=0.98, I2=0%). The safflower yellow injection with conventional therapy has a higher effective rate than the control group in relieving the symptoms of angina pectoris [odds ratio(OR)=2.95, 95%(CI)(1.81, 4.81)] and improving ischemic ECG [OR=2.85, 95% CI(1.67, 4.86)]. The difference was statistically significant in the "80 mg dosage" and "100 mg dosage" subgroups(P0.05) for improving clinical symptoms and ECG. The funnel graphic was nearly symmetrical. Sensitivity analysis suggested that the results were stable.CONCLUSION: Safflower yellow injection as an adjunct therapy with conventional drugs shows advantages in easing the clinical symptoms of unstable angina and improving ECG over basic therapy alone. However, the conclusions should be interpreted with care until more high-quality RCTs are reported. 展开更多
关键词 Safflower yellow injection Angina unstable Meta-analysis
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国际毛巾市场三大变化
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《光彩》 1995年第1期31-31,共1页
国际毛巾市场三大变化当前,国际毛巾市场出现了三大变化:变中低档为中高档品。如丝光缎档、闪光缎档、割绒缎档系列产品,工艺别致,款式新颖,有富贵豪华感,颇受消费者欢迎。变单一品种为系列配套。在用途配套方面,由洗面中、餐巾... 国际毛巾市场三大变化当前,国际毛巾市场出现了三大变化:变中低档为中高档品。如丝光缎档、闪光缎档、割绒缎档系列产品,工艺别致,款式新颖,有富贵豪华感,颇受消费者欢迎。变单一品种为系列配套。在用途配套方面,由洗面中、餐巾、浴中等组成,有供不同档次宾馆使用... 展开更多
关键词 毛巾市场 工艺配套 缎档 花色 多种原料 系列产品 系列配套 纯棉纱 高档品 丝光
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Identification of medaka magnetoreceptor and cryptochromes
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作者 Yunzhi Wang Jianbin Chen +1 位作者 Feng Zhu Yunhan Hong 《Science China(Life Sciences)》 SCIE CAS CSCD 2017年第3期271-278,共8页
Magnetoreception is a hallmark ability of animals for orientation and migration via sensing and utilizing geomagnetic fields.Magnetoreceptor(MagR) and cryptochromes(Cry) have recently been identified as the basis for ... Magnetoreception is a hallmark ability of animals for orientation and migration via sensing and utilizing geomagnetic fields.Magnetoreceptor(MagR) and cryptochromes(Cry) have recently been identified as the basis for magnetoreception in Drosophila.However,it has remained unknown whether MagR and Cry have conserved roles in diverse animals.Here we report the identification and expression of magr and cry genes in the fish medaka(Oryzias latipes).Cloning and sequencing identified a single magr gene,four cry genes and one cry-like gene in medaka.By sequence alignment,chromosomal synteny and gene structure analysis,medaka cry2 and magr were found to be the orthologs of human Cry2 and Magr,with cry1 aa and crylab being coorthologs of human Cry1.Therefore,magr and cry2 have remained as single copy genes,whereas cry1 has undergone two rounds of gene duplication in medaka.Interestingly,magr and cry genes were detected in various stages throughout embryogenesis and displayed ubiquitous expression in adult organs rather than specific or preferential expression in neural organs such as brain and eye.Importantly,magr knockdown by morpholino did not produce visible abnormality in developing embryos,pointing to the possibility of producing viable magr knockouts in medaka as a vertebrate model for magnet biology. 展开更多
关键词 magnetoreception MagR cryptochrome magnetogenetics
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