检索结果-南通市图书馆

high Performance Liquid Chromatographic Determination of Phenolic Acids in Fruits and Vegetables

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 1993年第4期6卷 389-398页

作者： LI PING, WANG xu-QlNG, WANG HlJAI-ZHOU, AND WU yong-NlNGinstitute of nutrition and food hygiene, chinese academy of preventive medicine, 29 Nanwei Road, beijing 100050, china institute of nutrition and food hygiene Chinese Academy of Preventive Medicine Beijing.

A simple isocratic HPLC technique has been developed for the quantitative analysis of phenolic acids (PAs) in fruits and vegetables. Nine benzoic and cinnamic acid derivatives were separated in less than 30 min, and the resolution was all more than 1.23. The ranges of linearity for PAs standards were 0.2-100 ng, even up to 600 ng (r = 0.983-1.000) and the detection limits were 0.02-0.24 mg/kg. Samples of fresh vegetables and fruits were extracted with 80% mcthanol and ethyl acetate, then purified with C18 Sep-Pak cartridge and determined by HPLC. This method was applied to the determination of PAs in 7 kinds of fruits and vegetables, i.e., apple, pear, chinese cabbage, cauliflower, turnip, soybean sprout and white grape wine. The content of the 9 PAs varied widely in the 7 kinds ol'foods studied. The average concentrations ofchlorogenic acid in apple (100.2 mg/kg) and pear (30.8 mg/kg) were quite high, and sinapinic acid was remarkable (42.5 mg/kg) in chinese cabbage, and protocatechuic acid had the highest concentration of all the PAs in white wine.

关键词： high Performance Liquid Chromatographic Determination of Phenolic Acids in Fruits and Vegetables

The Blocking Effect of Phenolic Acid on N-Nitrosomorpholine Formation in vitro

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 1994年第1期7卷 68-78页

作者： LI PlNG WANG HUAI-ZHOU WANG xu-QING AND WU yong-NING(institute of nutrition and food hygiene, chinese academy of preventivemedicine, 29 Nanwei Road, beijing 100050, china)( Present address: institute of Environmental Health and Engineering, chinese Acad institute of nutrition and food hygiene Chinese Academy of Preventive Medicine Beijing.

Phenolic acids (PAs) are widely found in many daily consumed vegetables and *** inhibitory effects of PAs on Nnitrosomorpholine (NMOR) formation in vitro undersimulated gastric juice condition were studied. The results showed that the inhibjtoryIX)tency of thirteen varieties of PAs differed greatly, which may be related to theirchemical structures; the blocking rate (BR) of different killds of PAs were as follows:caf feic acid, 92.5%; tannic acid, 90.0%; gallic acid, 86.8%; sinaPinic acid, 86.2%; ferulicacid, 8l.l%; chlorogenic acid, 69.4%; gentisic acid, 69.2%; syringic acid, 62.1%; protocatechuic acid, 56.0%; p-coumaric acid, 52.5%; vannilic acid, 35.4%; moreover,p-hydroxybenzoic acid and m-coumaric acid had the least blocking effect or even slightcatalyzing effect. The results also demonstrated that amounts of NMOR formed werenegatively correlated with molar ratio of PAs to nitrite and that the optimum pH forinhibition was between 2 and 3.

关键词： The Blocking Effect of Phenolic Acid on N-Nitrosomorpholine Formation in vitro

Two aquaporins,PIP1;1 and PIP2;1,mediate the uptake of neonicotinoid pesticides in plants

在线全文

学校读者我要写书评

暂无评论

Plant Communications 2024年第5期5卷 176-188页

作者： Qun Wan Yixin Li Jinjin Cheng Ya Wang Jing Ge Tingli Liu Liya Ma yong Li Jianan Liu Chunli Zhou Haocong Li Xing Sun Xiaolong Chen Qing X.Li Xiangyang Yu Key Laboratory of food Quality and Safety of Jiangsu Province State Key Laboratory Breeding BaseNanjing 210014China institute of food Safety and nutrition Jiangsu Academy of Agricultural Sciences50 Zhongling StreetNanjing 210014China Jiangsu Provincial Key Construction Laboratory of Special Biomass Resource Utilization Nanjing Xiaozhuang University3601 Hongjin AvenueNanjing 211171China Department of Molecular Biosciences and Bioengineering University of Hawaii at ManoaHonoluluHI 96822USA

Neonicotinoids(NEOs),a large class of organic compounds,are a type of commonly used pesticide for crop *** uptake and accumulation in plants are prerequisites for their intra-and intercellular move-ments,transformation,and *** the molecular mechanisms that underpin NEO uptake by plants is crucial for effective application,which remains ***,we demonstrate that NEOs enter plant cells primarily through the transmembrane symplastic pathway and accumulate mainly in the *** plasma membrane intrinsic proteins discovered in Brassica rapa,BraPIP1;1 and BraPIP2;1,were found to encode aquaporins(AQPs)that are highly permeable to NEOs in different plant species and facilitate NEO subcellular diffusion and *** conserved transport function was further demonstrated in Xenopus laevis oocyte and yeast ***1;1 and BraPIP2;1 gene knockouts and interaction as-says suggested that their proteins can form functional *** of the potential of mean force indicated a negative correlation between NEO uptake and the energy barrier of BraPIP1;1 *** study shows that AQPs transport organic compounds with greater osmolarity than previously thought,providing new insight into the molecular mechanisms of organic compound uptake and facilitating innovations in systemic pesticides.

关键词： neonicotinoid aquaporin Brassica rapa plasma membrane uptake systemic pesticide

Postharvest Quality and Physiological Behavior of Sweet Potato (Ipomoea batatas Lam.) Leaf Stalks Under Three Temperatures

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Agricultural Sciences in china 2009年第2期8卷 244-248页

作者： PENG Yan xu yong-quan DUAN Dao-fu MAO Lin-chun Department of food Science and nutrition College of Biosystem Engineering and Food Science Zhejiang University Hangzhou 310029 P.R.China Tea Research institute Chinese Academy of Agricultural Sciences Hangzhou 310008 P.R.China Maize Research institute Zhejiang Academy of Agricultural Sciences Dongyang 322100 P.R.China

Sweet potato （Ipomoea batatas Lam.） leaf stalks were cut into 20 cm length, and stored at 20, 6, and 2℃. The respiration rate, ethylene production, ascorbic acid, free amino acid, total chlorophyll content, freshness, and shelf life were determined during storage to investigate the effect of storage temperatures on the quality and physiological responses in sweet potato leaf stalks. Wound responses were observed as high respiration rate and ethylene production immediately after cutting. Sweet potato leaf stalks were found to be sensitive to chilling injury manifested as browning and water-soaking on the surface at 2℃. In contrast, sweet potato leaf stalks were susceptible to senescence, exhibited by etiolating and yellowing, at 20℃. Loss in weight and chlorophyll was minimized under low temperatures. high temperatures also caused the accumulation of amino acids with a significant loss of ascorbic acid and chlorophyll. Sweet potato leaf stalks had a storage life of 16 days at 6℃, 8 days at 2℃, and 6 days at 20℃, respectively.

关键词： sweet potato leaf stalks storage quality

在线全文

学校读者我要写书评

暂无评论

大豆肽的功能活性及在食品加工产业中的应用

中国调味品 2024年第6期49卷 200-205页

作者：程娟娟程江华蔡永萍万娅琼徐雅芫安徽农业大学生命科学学院合肥230036 安徽省农业科学院农产品加工研究所合肥230031 安徽省食品微生物发酵与功能应用工程实验室合肥230031

大豆肽是大豆蛋白水解后得到的小分子化合物,分子量小,一般由3~6个氨基酸组成。大豆肽富含多种生物活性成分,具有易吸收、高营养、低成本等优点,并且具有抗癌症、抗氧化、增强免疫力等生物功能,在食品、制药、化妆品等领域具有较好的应... 详细信息

大豆肽是大豆蛋白水解后得到的小分子化合物,分子量小,一般由3~6个氨基酸组成。大豆肽富含多种生物活性成分,具有易吸收、高营养、低成本等优点,并且具有抗癌症、抗氧化、增强免疫力等生物功能,在食品、制药、化妆品等领域具有较好的应用前景。但其存在应用限制因素,常见的限制因素如具有苦味、乳化性差、色泽不佳等,阻碍了其在生产中的大量使用。文章综述了大豆肽的功能和在食品加工中的应用情况,以期为大豆肽的综合利用提供理论依据。

关键词：大豆肽功能食品加工应用

表面增强拉曼光谱技术快速筛查白酒中对苯二甲酸二辛酯

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

食品安全质量检测学报 2024年第14期15卷 67-73页

作者：白永庆何平杨永陈军妃路燕徐桂锋赵菁蕾方慧文防城港市检验检测中心防城港市粮油安全与营养健康重点实验室防城港538001 武汉食品化妆品检验所国家市场监管重点实验室(食用油质量与安全)武汉430040 武汉轻工大学食品科学与工程学院武汉430023

目的建立表面增强拉曼光谱法(surface enhanced Raman spectroscopy,SERS)快速筛查白酒中对苯二甲酸二辛酯(dioctyl terephthalate,DOTP)的方法。方法采用水合肼将DOTP对还原成对苯二酸二肼,增强亲水性能,进而与金纳米粒子(Au nanoparti... 详细信息

目的建立表面增强拉曼光谱法(surface enhanced Raman spectroscopy,SERS)快速筛查白酒中对苯二甲酸二辛酯(dioctyl terephthalate,DOTP)的方法。方法采用水合肼将DOTP对还原成对苯二酸二肼,增强亲水性能,进而与金纳米粒子(Au nanoparticles,AuNPs)结合产生拉曼光谱增强效应而被测定。通过比较DOTP的亲水性修饰产物与对苯二酸二肼标准溶液的SERS谱图,确定方法的可行性。研究进一步探索最佳亲水性修饰反应条件和拉曼光谱测定条件,确定反应的温度、时间、水合肼用量以及促凝剂的浓度。结果在0.2~20.0μg/mL范围内,DOTP特征峰1612 cm^(-1)的强度与DOTP的浓度呈良好线性关系,相关系数(r)为0.993,检出限为0.1μg/mL。方法用于添加DOTP浓度为10、25、50mg/kg的白酒样品中DOTP快速筛查,结果准确可靠。结论本方法所需设备廉价易得,操作简单快速,在DOTP的现场快速检测方面具有良好的应用潜力。

关键词：对苯二甲酸二辛酯分子修饰表面增强拉曼光谱快速筛查

在线全文

学校读者我要写书评

暂无评论

美国营养项目对中国大豆消费的启示

中国食物与营养 2024年第1期30卷 30-34页

作者：王禹李干琼许世卫张永恩李灯华中国农业科学院农业信息研究所/北京市农业监测预警工程技术研究中心/中国农业科学院智能化农业预警技术与系统重点开放实验室/农业农村部农业监测预警技术重点实验室北京100081

目的:当前中国大豆产业支持主要集中在生产端,消费端缺乏项目支持,而当前国内大豆产业问题的解决,既要靠提升国内大豆产能,更重要的是优化大豆消费结构,提升国产大豆消费需求。方法:通过研究美国大豆产业支持政策,从政策目标、支出情况... 详细信息

目的:当前中国大豆产业支持主要集中在生产端,消费端缺乏项目支持,而当前国内大豆产业问题的解决,既要靠提升国内大豆产能,更重要的是优化大豆消费结构,提升国产大豆消费需求。方法:通过研究美国大豆产业支持政策,从政策目标、支出情况、执行情况、执行效果等不同角度揭示了作为美国农业支持支柱项目—营养项目在保障国民营养供应、饥饿改善和健康提升等方面的显著成效,同时对美国经济和工人就业也起到了积极的作用。结果:与美国营养项目支持相比,以豆制品消费为桥梁的国产大豆消费长效稳定机制还未建立,大豆消费支持项目可为低收入、儿童、学生等特殊人群营养健康提供保障,对于当前提升大豆优质农产品消费、促进大豆加工业发展、帮助农民增收、实现大豆消费和生产双赢具有积极作用。结论:建议通过尽快建立保障特殊人群豆制品需求的长短期机制,通过提升国产大豆消费,促进国内大豆产业链的健康发展。

关键词：农业项目支持政策营养项目消费结构消费补贴大豆消费

Derivation and applications of human hepatocyte-like cells

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Stem Cells 2019年第8期11卷 535-547页

作者： Shuang Li Shi-Qian Huang yong-xu Zhao Yu-Jie Ding Dan-Jun Ma Qiu-Rong Ding CAS Key Laboratory of nutrition Metabolism and Food Safety Shanghai Institute of Nutrition and Health Shanghai Institutes for Biological Sciences University of Chinese Academy of Sciences Chinese Academy of Sciences Shanghai 200031 China College of Mechanical Engineering Dongguan University of Technology Dongguan 523808 Guangdong Province China Department of Pharmacy Mudanjiang Kang’an Hospital Mudanjiang 157011 Heilongjiang Province China institute for Stem Cell and Regeneration Chinese Academy of Sciences Beijing 100101 China

Human hepatocyte-like cells (HLCs) derived from human pluripotent stem cells (hPSCs) promise a valuable source of cells with human genetic background, physiologically relevant liver functions, and unlimited supply. With over 10 years’ efforts in this field, great achievements have been made. HLCs have been successfully derived and applied in disease modeling, toxicity testing and drug discovery. Large cohorts of induced pluripotent stem cells-derived HLCs have been recently applied in studying population genetics and functional outputs of common genetic variants in vitro. This has offered a new paradigm for genomewide association studies and possibly in vitro pharmacogenomics in the nearly future. However, HLCs have not yet been successfully applied in bioartificial liver devices and have only displayed limited success in cell transplantation. HLCs still have an immature hepatocyte phenotype and exist as a population with great heterogeneity, and HLCs derived from different hPSC lines display variable differentiation efficiency. Therefore, continuous improvement to the quality of HLCs, deeper investigation of relevant biological processes, and proper adaptation of recent advances in cell culture platforms, genome editing technology, and bioengineering systems are required before HLCs can fulfill the needs in basic and translational research. In this review, we summarize the discoveries, achievements, and challenges in the derivation and applications of HLCs.

关键词： Hepatocyte-like cells Human pluripotent stem cells Hepatic differentiation Biomedical application

Studies on BN rats model to determine the potential allergenicity of proteins from genetically modified foods

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2005年第34期11卷 5381-5384页

作者： xu-Dong Jia Ning Li yong-Ning Wu Xiao-Guang Yang National institute for nutrition and food Safety Chinese Center for Disease Control and Prevention 29 Nanwei Road Beijing 100050China

AIM： To develop a Brown Norway （BN） rat model to determine the potential allergenicity of novel proteins in genetically modified food. METHODS： The allergenicity of different proteins were compared, including ovalbumin （OVA）, a potent respiratory and food allergen, bovine serum albumin （BSA）, a protein that is considered to have a lesser allergenic potential, and potato acid phosphatase （PAP）, a non-allergenic protein when administered to BN rats via different routes of exposure （intraperitoneally or by gavage）. IgG and IgE antibody responses were determined by ELISA and PEA, respectively. An immunoassay kit was used to determine the plasma histamine level. In addition, possible systemic effect of allergens was investigated by monitoring blood pressure. RESULTS： OVA provoked very vigorous protein-specific IgG and IgE responses, low grade protein-specific IgG and IgE responses were elicited by BSA, while by neither route did PAP elicit anything. In either routes of exposure, plasma histamine level in BN rats sensitized with OVA was higher than that of BSA or PAP. In addition, an oral challenge with BSA and PAP did not induce any effect on blood pressure, while a temporary drop in systolic blood pressure in few animals of each routes of exposure was found by an oral challenge with OVA. CONCLUSION： BN rat model might be a useful and predictive animal model to study the potential allergenicity of novel food proteins.

关键词： Animal model food protein Allergenicity