叶黄素酯和叶黄素抗氧化作用比较

目的:研究叶黄素酯和叶黄素的抗氧化作用.方法:采用不同工艺制备叶黄素酯和叶黄素,通过体外还原能力试验及清除超氧阴离子自由基(O2·-)和羟基自由基(0H·)试验,测定并比较它们的抗氧化活性.结果:在还原能力试验中,叶黄素、叶黄素酯的还原能力远高于同浓度的VE,叶黄素的还原能力略高于叶黄素酯:在清除0H·和O2·-试验中,叶黄素酯和叶黄素的清除能力略高于BHT和VE,叶黄素酯清除0H·的能力略强于叶黄素,50%清除浓度EC50分别为0.88、1.36 mg/100 mL;叶黄素酯和叶黄素清除O2·-的EC50值基本相同,50%清除浓度EC50分别为1.11、1.07mg/100mL.结论:叶黄素和叶黄素酯都具有较强的清除自由基能力和抗氧化活性.叶黄素酯的光热稳定性强于叶黄素的.     

梅花鹿胎盘多肽体外抗氧自由基及抗油脂氧化性能的研究

研究了鹿胎盘多肽的抗氧化性.鹿胎盘多肽具有清除羟基自由基(·OH)、超氧自由基(O2-·)和H2O2的能力,同时时油脂有一定的抗氧化作用.随着多肽浓度的增大,抗氧化能力进一步增强.当鹿胎盘多肽浓度达到200μg/mL时,对·OH、O2,'->·、H2O2的抑制率分别为42.4%、73.7%、65.2%.在猪油贮藏的第7d,加入200、300μL浓度为200μg/mL的鹿胎盘多肽,其抗氧化作用比0.02%的BHT分别高28.83%、33.95%.     

水栒子果肉黄酮的体外抗氧化活性研究

以水枸子果肉总黄酮的粗提物为原料,测定其体外抗氧化能力.利用匀浆法提取水枸子果肉黄酮,比色法测定其含量.采用1,1-二苯基-2-三硝基苯肼（DPPH）自由基清除法、2,2-吖嗪双（3-乙基-7-苯并噻唑啉磺酸）二铵盐（ABTS）自由基清除法、超氧阴离子自由基清除法（SRSA）、还原能力测定法和铁离子还原/抗氧化能力法（FRAP）,对其进行体外抗氧化活性研究.结果表明,水枸子果肉总黄酮的自由基清除能力和还原能力随总黄酮浓度的升高而增强,DPPH自由基清除能力和超氧阴离子自由基（O2·）清除能力与特丁基对苯二酚（TBHQ）相当,高于丁基羟基甲苯（BHT）、丁基羟基茴香醚（BHA）、VC、VE; ABTS清除能力高于BHT、VC、VE,略低于TBHQ和BHA;还原能力与TBHQ相当,高于BHT、VE,略低于BHA和VC;铁还原能力与TBHQ相当,高于BHT、VC、VE,低于BHA.水枸子果肉黄酮有较强的体外抗氧化能力,具有很好的开发潜力.     

紫薯花青素体外抗氧化及对H_2O_2诱导HepG2细胞氧化损伤的保护作用

目的:研究紫薯花青素的体外抗氧化作用,建立H2O2诱导Hep G2细胞氧化损伤模型,初步评价紫薯花青素的抗氧化应激作用。方法:紫薯干粉经过提取、纯化制得紫薯花青素干粉,分别测定紫薯花青素的总还原力、对羟自由基(·OH)、超氧阴离子自由基(O2-·)的清除能力以及对大鼠红细胞溶血的保护作用。建立H2O2诱导Hep G2细胞氧化损伤模型,采用四甲基偶氮唑蓝(methyl thiazolyl tetrazolium,MTT)法检测不同质量浓度紫薯花青素对Hep G2细胞氧化损伤的保护作用。结果:紫薯花青素的还原力和VC基本相当;紫薯花青素对·OH有很好的清除效果,在实验浓度范围内有明显的剂量-效应关系;随紫薯花青素浓度的升高,对O2-·的清除作用增强,呈现良好的量-效关系,单位浓度的紫薯花青素对O2-·的清除作用比2,6-二叔丁基-4-甲基苯酚(butylated hydroxytoluene,BHT)效果好。不同质量浓度的紫薯花青素均可抑制H2O2诱导的大鼠红细胞溶血,且随着紫薯花青素质量浓度的升高,大鼠红细胞的溶血度降低,呈现良好的量-效关系。H2O2诱导的Hep G2细胞氧化损伤模型中,50~1 600μg/m L的紫薯花青素均能够抑制H2O2引起的Hep G2细胞凋亡,当紫薯花青素质量浓度达到800μg/m L时,Hep G2细胞存活率为(88.03±7.48)%。结论:紫薯花青素具有良好的体外抗氧化作用,并对H2O2诱导Hep G2细胞氧化损伤具有明显的保护作用,研究初步揭示了紫薯花青素具有体外抗氧化作用。     

菠菜色素蛋白复合物的抗氧化性研究

从菠菜叶中以硫酸铵沉降方式提取色素蛋白复合物,分析复合物中的主要功能成分,并以VC、BHT为对照,以总抗氧化能力和DPPH、·OH及O2-·等自由基的清除能力及亚油酸体系的抗氧化作用为指标,研究色素蛋白复合物的抗氧化能力及色素蛋白复合物与VC或BHT之间的相互作用.结果表明,在水相体系中复合物的总抗氧化能力为12.83 μ/mg复合物,与BHT相当,明显低于VC,当复合物浓度在10 μg/mL～500μg/mL时,对DPPH、·OH及O2-·等自由基的最大清除能力强于VC和BHT,分别为81.97％,88.14％和83.36％;以不同比例对复合物与VC或BHT进行复配,总浓度为100 μg/mL,与相同浓度色素蛋白复合物、VC或BHT单独作用时清除能力相比,发现VC与复合物之间存在协同增效作用,BHT无此效果.     

樱桃叶黄酮的体外抗氧化活性

考察樱桃叶黄酮的体外抗氧化活性,为樱桃叶黄酮在医药、食品方面的应用提供理论依据。从樱桃叶中提取黄酮,体外检测樱桃叶黄酮对羟自由基(·OH)和超氧阴离子自由基(O2-·)的清除作用,以及对H2O2诱发小鼠红细胞氧化溶血和肝脂质过氧化反应的抑制作用。结果显示,樱桃叶黄酮对·OH和O2-·具有清除作用,且呈现质量浓度依赖性,30μg/mL的黄酮溶液对·OH和O2-·的清除率分别达到85.67%和72.45%,并且对·OH的清除能力优于维生素C;樱桃叶黄酮对肝匀浆脂质过氧化反应和过氧化氢(H2O2)诱发红细胞氧化溶血具有抑制作用,当终质量浓度为30μg/mL时,抑制率分别为79.82%和75.54%。表明樱桃叶黄酮具有质量浓度依赖性的体外抗氧化活性。     

酸水解法提取酸浆果结合酚工艺及抗氧化活性

以酸浆果为试材,研究H2SO4体积浓度、液料比、水解时间、提取温度对酸浆果结合酚得率的影响及结合酚体外抗氧化能力。采用中心组合设计优化结合酚提取工艺,通过·OH、ABTS^+·及FRAP法评价结合酚体外抗氧化能力。结果表明,酸浆果结合酚最佳提取工艺为:H2SO4浓度5%,液料比55︰1 mL/g,水解时间16 h,提取温度45℃。此条件下提取得到的结合酚含量8.83±0.18 mg/g。酸浆果结合酚还原铁能力与BHT相当,比VC强,酸浆果游离酚原铁能力介于BHT与VC间(p<0.01);酸浆果结合酚、游离酚都有一定的ABTS^+·清除能力,都比VC、BHT清除能力弱(p<0.01),对·OH基团表现出一定还原能力,均比VC、BHT清除能力弱(p<0.01)。研究为酸浆果结合酚开发和利用提供依据,避免资源浪费。     

鱼腥藻藻蓝蛋白的抗氧化作用

目的:探讨鱼腥藻藻蓝蛋白(AnabaenaPhycocyaninAPC)的体外抗氧化作用。方法:采用化学比色法测定APC在体外的(1)总抗氧化能力;(2)抑制活性超氧阴离子自由基(O2·)的能力;(3)清除羟自由基(·OH)的能力;(4)在其作用下的小鼠肝组织中脂质过氧化产物丙二醛(MDA)含量的变化。结果:一定浓度范围内不同纯度的APC均有总抗氧化能力,能清除O2·和·OH及抑制MDA的生成,且呈现一定剂量关系。结论:APC在一定浓度范围内具有抗氧化作用。--     

襄荷乙醇提取物的体外抗氧化活性研究

目的:研究襄荷乙醇提取物(extract of Zingiber mioga Rose,EZR)的体外抗氧化作用.方法:用50%乙醇制备襄荷提取物,以V0作为阳性对照,测定EZR的总还原力及清除DPPH自由基的能力,并用荧光化学发光法测定了EZR对活性氧自由基(O2-·、·OH、H2O2)的清除能力.结果:EZR的总还原力为40.17±1.04mg Vc/g,在实验浓度范围内,对DPPH·、·OH、O2-·、H2O2的清除率分别达到了70%、64%、77%、71%.结论:EZR具有明显的体外抗氧化活性,但其抗氧化能力小于Vc.     

流动注射化学发光测定苹果多酚抗氧化活性

用流动注射化学发光法测定苹果多酚的体外抗氧化作用。将苹果多酚提取液加入3种化学发光体系,测量其发光强度,根据系统化学发光被抑制的程度评价苹果多酚对活性氧自由基的清除能力,并以抗坏血酸(VC)为阳性对照。结果表明,苹果多酚对三种活性氧自由基(O2-·、·OH、H2O2)的清除能力远强于VC;对H2O2和·OH的清除能力相当,强于对O2-·的清除能力。结果显示苹果多酚具有很好的抗氧化能力。     

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.     

An internet compendium of analytical methods and spectroscopic information for monomers and additives used in food packaging plastics

An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.     

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.     

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