高效液相色谱法测定β-酪啡肽

以SinoChrom 300A C8柱为分离柱,对高效液相色谱法测β-酪啡肽进行了研究.结果表明,以水(内含体积分数为0.1%TFA)和体积分数95%乙腈(内含体积分数为0.1%TFA)分别为流动A相和B相,在梯度洗脱流速1.0 mL/min,检测波长215 nm条件下,β-酪啡肽-5和β-酪啡肽-7被有效分离且具有较大的响应值,峰面积和保留时间具有良好的稳定性.同时在β-酪啡肽-5和β-酪啡肽-7质量浓度分别为1.0 g/L和1.2 g/L时,进样体积与峰面积呈良好的线性关系(回归系数r分别为0.9950和0.9955).该法可快速准确分离分β-酪啡肽.     

β-酪啡肽-7生物活性肽的检测研究

研究了β-酪啡肽-7的分析检测方法。以β-酪啡肽-7标准品进行了色谱条件的探索,包括分离柱,流动相的选择以及柱温,柱压、流速、检测波长和灵敏度的选择,最后建立了简单有效的检测方法,并确定了β-酪啡肽-7高效液相色谱的检测条件。     

反相高效液相色谱法检测大豆蛋白外啡肽的研究

大豆蛋白序列中隐藏着外啡肽β-酪啡肽-3(β-CM-3)的片段,使得大豆肽食品中含有外啡肽β-CM-3成为可能,因此有必要对大豆肽食品进行外啡肽β-CM-3定性和定量的检测。采用反相液相色谱的方法,以β-酪啡肽-3标准品进行了包括分离柱、流动相的选择、柱温、柱压、流速、检测波长和灵敏度等色谱条件的探索,得出检测条件为波长220nm,柱温25℃,进样量10μL,采用等度洗脱,洗脱条件为:含0·1%TFA的14%乙腈溶液。流速0·9mL/min,洗脱时间为60min。该方法的相对标准偏差为4·07%,平均回收率为95·3%,最小检测浓度为0·4μg/mL。对照标准品保留时间和峰面积,得出酸性蛋白酶/Alcalase=4h/2h酶解液中含有目标外啡肽156·41μg/g。     

酪蛋白酶解液中β-酪啡肽-7的液相色谱检测

研究活性多肽β-酪啡肽-7的检测.采用高效液相色谱法对胃蛋白酶解样品中活性肽(β-酪啡肽-7)进行测定.结果表明,对比标准品的保留时间发现水解0.5,1.5,2.5h的1,3,5号样品含有β-酪啡肽-7.经过重复进样,结果仍然一致.     

乳源β-酪啡肽-7对老年小鼠肾功能的影响

本文研究了β-酪啡肽-7对老年小鼠肾功能可能的影响。50只雄性昆明小鼠,按组分别灌胃0.90%的生理盐水和低、中、高剂量的β-酪啡肽-7。连续灌胃30d后,收集所有小鼠的血清及组织样本进行检测。组织病理学研究显示β-酪啡肽-7对老年小鼠的肾脏组织老化有一定改善作用,但高剂量组小鼠的肾小体肿胀似乎没有减轻,并且上皮细胞有坏死脱落现象。与模型组相比,中剂量组小鼠的血清肌酐(CRE)水平、肾脏组织中总抗氧化能力(T-AOC),超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GPx)活性分别增加了22.16%、69.02%、71.26%(p0.05)和24.41%,而高剂量组分别增加了13.12%、64.88%、67.33%(p0.05)和17.90%。提示β-酪啡肽-7可以调节老年小鼠的肾功能,增加其抗氧化能力,但不是剂量依赖式作用。此外,干预低中剂量β-酪啡肽-7小鼠的MDA含量都比模型组低(分别降低了15.40%、3.17%),但高剂量组反而提升了16.08%,说明高剂量组小鼠肾脏的氧化有所加重。上述结果表明,β-酪啡肽-7有改善老年小鼠肾功能异常的可能,可能通过提高抗氧化能力来改善衰老引起的老化损伤,但摄入过多β-酪啡肽-7似乎会加重肾脏负担。     

乳源β-酪啡肽-7对自然衰老小鼠的抗衰老作用研究

探讨了乳源β-酪啡肽-7对自然衰老小鼠的抗衰老作用及其可能机制。选取10只2月龄C57小鼠作为青年对照组;40只16-18月龄C57小鼠随机分为自然衰老模型组β-酪啡肽-7处理组,其中β-酪啡肽-7处理组小鼠在饲喂与模型组相同日粮的基础上,每天灌胃高、中、低3种剂量的β-酪啡肽-7溶液。连续喂养60d后,眼眶采血吸取上清;采血后颈椎脱臼处死,取心脏、肝脏、肾脏、大脑等组织并称重,测定各组小鼠脏器系数以及血清和脏器匀浆液中SOD、MDA、MAO及GSH-Px含量。结果显示:(1)β-酪啡肽-7组对改善自然衰老小鼠脏器指数有促进作用;(2)β-酪啡肽-7能够提高自然衰老小鼠的SOD、GSH-Px活性,降低MDA、MAO在体内的堆积。结果表明添加乳源-酪啡肽-7可以有效改善自然衰老小鼠的脏器指数,缓解自然衰老小鼠的氧化应激反应,且随着灌胃β-酪啡肽-7剂量的增加,延缓衰老效果越显著。     

乳源酪啡肽的研究进展

80年代以来，国外一些学者相继从酪蛋白的酶解产物中发现生物活性肽，证明乳除了具有营养作用外，还具有重要的生理作用。酪啡肽就是其中重要的乳源阿片肽，自从1979年Brantl等人首先从酪蛋白的水解产物中分离到β-酪啡肽-7，对于酪啡肽的制备、分离、纯化等各个方面均有广泛的研究。随着具各种生物活性的短肽的不断发现，其研究和开发日益受到各国学者的关注。     

乳源β-酪啡肽-7对老年小鼠肝脏氧化应激的影响

观察乳源β-酪啡肽-7对老年小鼠肝脏氧化应激的影响。方法:32只老年雄性昆明小鼠随机分为四组(每组8只):模型对照组、低剂量组、中剂量组、高剂量组,另设空白对照组,二月龄雄性昆明小鼠8只。对照组和模型组用0.9%的生理盐水连续灌胃30d,各剂量组分别灌胃β-酪啡肽-7溶液2×10-7mol/d、1×10-6mol/d、5×10-6mol/d。连续灌胃30 d后,小鼠颈椎脱臼处死,取肝脏等组织进行超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和单胺氧化酶(MAO)活性与丙二醛(MDA)含量测定。结果显示β-酪啡肽-7能显著提高老年小鼠肝脏超氧化物歧化酶活性(P0.05),谷胱甘肽过氧化物酶、单胺氧化酶活性变化无统计学差异,而低、高剂量组丙二醛含量显著增加(P0.05)。结论为β-酪啡肽-7有提高老年小鼠肝脏抗氧化应激的可能,其机制可能与提高老年小鼠肝脏的超氧化物歧化酶活性有关。     

β-Casomorphin-7的酶联免疫吸附分析(ELISA)方法的建立

β－酪啡肽－7（β－Casomorphin-7)是一个有代表性的乳源外啡肽，有调节动物消化道运动和采食、内分泌、免疫等多种生物学功能。本研究以β－Casomorphin-7与人血清白蛋白（HSA）经戊二醛交联的复合物作为包被抗原；一抗为鸡抗β－Casomorphin-7与牛血清白蛋白（BSA）交联复合物的抗血清；酶标二抗为兔抗鸡IgG经戊二醛与辣根过氧化物酶（HRP）交换的复合物。包被抗原和一抗的稀释度经方阵稀释实验确定。本实验所建立的竞争ELISA方法的孔间差异为3．3％，板间差异为8．6％，检测灵敏度20ng/ml，检测范围20－320ng/ml，在实验浓度范围内。β－Casomorphin-7的抗血清与β－内啡肽、脑啡肽、强啡肽、精氨酸降压素和神经降压素等活性肽未显示免疫交叉反应。表明所建立的方法有较高的特异性，可用于酪啡肽的体内功能研究。     

β-酪啡肽对早期断奶仔猪生长性能及小肠形态、菌群、吸收功能的影响

将26头21日龄早期断奶仔猪随机均分2组.在其日粮中添加β-酪啡呔,探讨β-酪啡呔对其生长性能及小肠形态、菌群、吸收功能的影响.经3周饲喂后发现①第1周至第3周的日增重分别提高33.33%(P<0.01)、16.13%(P<0.05)和2.5%(P>0.05),饲料转化率分别提高13.73%、6.11%和1.21%,腹泻率分别降低41.67%(P<0.05)、10%(P>0.05)和0%;②在第1周内能极显著(P<0.01)地改善小肠形态、菌群以及对D-木糖的吸收能力,而第2周后差异不再显著(P>0.05);③β-酪啡肽在仔猪早期断奶后1～2周内投喂,是缓解断奶应激最合理的一种经济方式.     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

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.     

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     

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.     

National Development and Reform Commission Issued Announcement for Selection of Major Preliminary Research Projects for the "13~(th) Five-Year Plan"

In Apri Commi major p Plan＂ （h 2014, the National Development and Reform ssion issued an announcement for selection of reliminary research projects for the ＂13th Five-Year ereafter referred to as ＂The Announcement＂）     

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 scientific     

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,