HPLC测定撑篙竹竹叶中异牡荆苷的含量

建立HPLC测定撑篙竹竹叶中异牡荆苷的含量。采用反相高效液相色谱法,色谱柱:Z0RBAX SB-C18(2.1 mm×100 mm,3.6μm),甲醇(A)-0.1%冰醋酸水溶液(B)为流动相,梯度洗脱(0 min~3 min,85%~70%B;3 min~6 min,70%~55%B;6 min~9 min,55%~35%B;9 min~12 min,35%~35%B;12 min~15 min,35%~70%B;15 min~18 min,70%~85%B),流速0.6 mL/min,检测波长340 nm,柱温30℃。异牡荆苷在1.733 1μg/mL~10.832 0μg/mL呈良好的线性关系(r=0.999 6),平均回收率为98.01%,RSD1.02%,试验测得异牡荆苷的含量为2.928 5 mg/g。     

高效液相色谱法测定奶粉中酪蛋白磷酸肽的含量

采用高效液相色谱(HPLC)法对奶粉中酪蛋白磷酸肽(CPP)含量进行测定,样品通过调节p H、超声提取、离心分离和浓缩等方式进行前处理,C18柱分离,流动相为乙腈+0.1%TFA和水+0.1%TFA,梯度洗脱,检测波长215 nm,以保留时间定性,外标法定量,并与钡-乙醇沉淀法测定的结果进行对比。结果表明,HPLC检测CPP与杂质分离效果良好,线性范围0.1~2.0 mg/m L,加标0.1%~0.3%,回收率97.59%~100.00%;并测定多个厂家奶粉中的微量CPP,与实际添加量较接近,适用性良好,表明该方法简便,准确度和灵敏度高,其检测限为15.34 mg/kg、定量限为51.14mg/kg,适用于奶粉中微量CPP含量检测。钡-乙醇沉淀法测定奶粉中CPP含量结果与实际差别太大,不适用于奶粉中CPP含量的测定。     

LC-MS法测定钙片中酪蛋白磷酸肽含量

用液相色谱-质谱联用法,以选择离子模式(SIM)检测钙片中酪蛋白磷酸肽(CPP)含量。结果表明,该法前处理简便,专属性好,灵敏度高,检出限为1μg/ml,在1～100μg/ml范围内线性回归方程为y=3074.6x+684.6,R2=0.999,回收率为96%～104%,可用于测定钙片中CPP的含量,也可用于其它钙强化剂中添加CPP的检测。     

HPLC测定阿昔莫司缓释片的含量

目的建立采用高效液相色谱(HPLC)测定阿昔莫司缓释片含量的方法。方法采用Agilent TC-C_(18)色谱柱(4.6 mm×150 mm,5μm),流动相为0.13%庚烷磺酸钠溶液-甲醇-冰醋酸(85:15:1),检测波长为273 nm,流速为1 mL/min。结果阿昔莫司在19.63~98.16μg/mL范围内线性关系良好(r=0.9999),平均回收率为99.61%,RSD为0.60%。结论本方法准确、高效,可用于阿昔莫司缓释片质量控制。     

高效液相色谱法同时测定泡蒜中的有机酸

建立了HPLC同时测定泡蒜中有机酸含量的分析方法。通过色谱条件的优化,确定了泡蒜中有机酸含量测定的最佳色谱条件:色谱柱为Agilent ZORBAX SB-Aq(4.6mm×250mm,5μm),流动相为0.01mol/L磷酸氢二铵(pH 2.5)和甲醇溶液,流速0.6mL/min,柱温30℃,检测波长220nm。在此条件下,酒石酸等6种有机酸可得到很好的分离和测定。该方法各种酸的线性范围为0.001~1.000mg/mL,标准曲线相关系数均在0.9999以上,精密度检测RSD为0.07%~0.36%(n=5),重复性检测RSD为0.43%~4.64%(n=5),回收率为96.25%~105.57%。该方法简单、快捷、准确、重复性好,可应用于泡蒜成品中有机酸的同时测定。     

红葡萄酒中合成色素的测定研究

建立了HPLC测定红葡萄酒中色素柠檬黄、苋菜红、日落黄、胭脂红含量的方法,采用色谱柱:THERMO C18(4.6 mm×250 mm,5μm),检测波长:254 nm,流量:1.0 mL/min,进样量:10μL,流动相:0.02 mol/L乙酸铵与甲醇。梯度条件为:甲醇20%~35%,3%/min;35%~98%,9%/min;98%继续6 min。结果表明:柠檬黄、苋菜红、胭脂红、日落黄在0~50μg/mL范围内呈现良好的线性关系,Y=30 264 440X+3 047.2(R=0.999 8)、Y=29 741 606.67X+607.03(R=0.999 8)、Y=28 790 266.67-6 523.42(R=0.999 8)、Y=25 122 776.67X+1 953.58(R=0.999 8)。色素在24 h内稳定。本方法简单,快速、准确、重现性好,可以用作葡萄酒中色素的含量测定。     

HPLC法测定冬枣环磷酸腺苷含量

采用HPLC法对冬枣中环磷酸腺苷(cAMP)含量进行测定。色谱条件:色谱柱为Hypersil-ODS2(25cm×4.6mm,5μm)柱,流动相为V(甲醇):V(0.05mol/L磷酸二氢钾)=10:90,流速1.0mL/min,紫外检测器UV254nm×0.2AUFS。测定结果表明:标准曲线在1μg/mL～50μg/mL范围内线性良好,回收率为99.14%,相对标准误差为1.32%(n=6)。     

腈纶中残留DMSO含量的研究

采用HPLC法对腈纶中的DMSO含量进行测定。色谱条件为:色谱柱ODSC18柱(250mm×4.6mm,5μm),流动相为甲醇-水(25∶75),流速1.0mL/min,紫外检测波长245nm,灵敏度0.1AUFS。测定结果表明:标准曲线在0.02￣0.64mg/mL范围内线性良好,回收率为99.82%,相对标准误差(RSD)为1.53%。     

高效液相色谱法测定保健食品多维康胶囊中叶酸的含量

目的建立高效液相色谱法(high performance liquid chromatography,HPLC)测定多维康胶囊中叶酸含量的方法。方法采用C₁₈(150mm×4.6mm,5μm)色谱柱,以磷酸二氢钾-甲醇溶液为流动相,流速0.8 mL/min,检测波长254 nm,柱温30℃,进样体积10μL。结果叶酸的线性关系良好,相关系数为1.000;方法检出限为0.034μg/mL,定量限为0.091μg/mL;方法平均加标回收率为98.80%~104.17%,平均相对标准偏差为0.02%。结论该方法操作简单,灵敏度高,可作为保健食品多维康胶囊中叶酸的测定方法。     

高效液相色谱法测定秘鲁鱿鱼肌肉中的有机酸

研究建立了高效液相色谱(HPLC)同时测定秘鲁鱿鱼肌肉中多种有机酸的方法。有机酸的分离采用Atlantis T3色谱柱(4.6 mm×150 mm,5μm),流动相为0.08 mol/L KH_2PO_4(pH 3.00),流速0.5 mL/min,柱温30℃,检测波长210 nm。丙酮酸、苹果酸、α-酮戊二酸、乳酸、乙酸、柠檬酸、富马酸、丁二酸、丙酸等9种有机酸均能够得到很好的分离,其相关系数均在0.999以上,相对标准偏差为0.03%~0.37%,有机酸的回收率为94.5%~105%。     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Review of techniques to manufacture micro-hydrogel particles for the food industry and their applications

Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.     

12—A CRITIQUE OF SOME HYPOTHESES RELATING TO THE HETEROGENEITY OF THE HIGH-SULPHUR PROTEINS OF WOOL

Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of     

The Latest Data about Development of Chinese Printing Industry in 2013

In the 2014 China（Shanghai）International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;     

The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)"

正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly     

China textile machinery: taking off in progress

正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,     

Top Ten News of China's Paper Industry 2013

On December 24th, 2013, the meeting on the selection of top 10 news of China＇s paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.