油茶籽毛油中多酚类物质对自由基的清除作用

油茶籽油具有重要的保健功能和药效功能.通过油茶籽毛油中多酚类物质对不同种自由基清除的活性作用研究,其结果表明,油茶籽毛油中多酚类物质对羟基自由基和超氧阴离子自由基有良好的清除作用,加入多酚样品的质量浓度在0.53～7.29 μg/mL范围内,对羟基自由基的清除率高达65.21%以上;不同极性的多酚类物质清除效果不同,极性大的多酚类物质其总抗氧化能力较弱,对自由基的清除能力较强,为开发功能性油脂提供理论依据.     

油茶籽油抗氧化及对自由基清除作用研究

以贵州册享农家油茶籽油为原料,添加不同浓度的茶多酚（TP）、TBHQ以及不添加为对照,贮藏在（62±2）℃的温度条件下,观察贮藏过程中酸值、过氧化值（POV）的变化;同时提取不同处理油茶籽油中多酚类物质测定贮藏前后总酚、抗氧化能力及对自由基的清除作用。结果表明：茶多酚的抗氧化效果高于TBHQ及对照组,随着添加浓度的升高而增加。高温贮藏后从油茶籽油中提取的酚类物质具有很强的抗氧化能力;对DPPH、羟基自由基和超氧阴离子自由基有良好的清除作用。其中0.02%TP＞0.03%TP＞0.04%TP＞TBHQ＞空白。     

4种油茶籽油中多酚类物质的抗氧化活性比较研究

采用80%乙醇溶液分别提取雅安当地的白花和红花油茶籽毛油与精炼油中的多酚类物质,比较研究这4种油茶籽油中多酚类物质的抗氧化活性。结果表明:多酚类物质的含量分别为1.41(白花油茶籽毛油)、1.04(白花油茶籽精炼油)、0.75(红花油茶籽毛油)、0.68μg/mL(红花油茶籽精炼油);4种油茶籽油多酚类物质均表现出较强的抗氧化活性,并随多酚含量的增加而增强;白花油茶籽油中多酚类物质的抗氧化能力均强于红花油茶籽油中的;毛油相对于精炼油均具有更强的抗氧化作用;白花油茶籽毛油中多酚类物质的抗氧化活性不稳定。     

栝楼籽油清除自由基作用研究

以栝楼籽油清除羟基自由基能力和对超氧阴离子自由基的清除能力为指标,研究了栝楼籽油的抗氧化活性。实验表明栝楼籽油具有较好的清除超氧阴离子自由基的作用,最大抑制率为68.19%。栝楼籽油具有较好的清除羟自由基的作用,EC50为0.23mg/ml,具有明显的抗氧化作用。     

洋葱油的抗氧化活性研究

探讨洋葱油对羟基自由基、超氧阴离子自由基、过氧化氢的清除作用以及对羟基自由基引发DNA损伤的抑制作用,并与天然抗氧化剂Vc作比较。结果显示洋葱油对羟基自由基的清除作用及对羟基自由基引发DNA损伤的抑制作用效果明显,与Vc相当。对超氧阴离子自由基、过氧化氢的也有一定的清除作用,效果稍差于Vc。研究表明,洋葱油具有很好的抗氧化作用。     

猕猴桃根提取物体外抗氧化作用的研究

探讨猕猴桃根提取物的体外抗氧化作用.采用DPPH自由基、超氧阴离子、羟基自由基、过氧化氢和还原力的反应体系,测定猕猴桃根提取物的体外抗氧化作用,并用VC进行对照实验.实验条件下,ERHM对DPPH自由基、超氧阴离子(·O2-)、羟基自由基(·OH)、过氧化氢H2O2等均有较强的清除或抑制作用,且显示较好的量效关系,同时具有一定的还原力.其消除DPPH自由基的EC50为8.03 μg/mL,清除超氧阴离子(·O2-)的EC5o为1.28 mg/mL,抑制羟基自由基(·OH)能力可达69.4％,浓度为100 μg/mL时对过氧化氢(H2O2)的清除率为42％.猕猴桃根提取物具有较强的还原力,能有效清除DPPH和超氧阴离子自由基,并抑制羟基自由基的产生.所以,ERHM有效成分具有较为显著的抗氧化作用.     

椰肉乙醇提取物抗氧化性的研究

主要从清除超氧阴离子自由基、还原力、清除DPPH自由基、清除羟基自由基等方面,研究椰肉乙醇提取物的抗氧化性.结果表明,椰肉乙醇提取物对超氧阴离子自由基、DPPH·自由基和羟基自由基都有较强的清除能力;与VC、BHT和没食子酸相比较,椰肉乙醇提取物对Fe2+的络合能力最强;同时椰肉乙醇提取物还有一定的还原能力.因此,椰肉乙醇提取物是一种具有全面抗氧化功效的活性物质,具有很好的保健功能.     

杏仁皮中黄酮类化合物抗氧化性的研究

从清除超氧阴离子自由基、还原力、清除DPPH自由基、清除羟基自由基等方面,研究杏仁皮中黄酮类化合物的抗氧化性.结果表明,杏仁皮中黄酮类化合物的还原能力较强,对DPPH·自由基和羟基自由基有较强的清除能力,对Fe~(2+)的络合能力和脂质体过氧化反应的抑制作用也较强,但对超氧阴离子自由基的清除能力较弱.因此,杏仁皮中黄酮类化合物是一种抗氧化功效较强的活性物质,具有很好的保健功能.     

红花油茶籽油的抑菌和抗氧化作用研究

研究了红花油茶籽油对细菌、酵母菌、霉菌的抑制作用,以及其清除自由基和抗油脂氧化功效。结果表明,红花油茶籽油能很好地清除超氧阴离子自由基O2-.;对菜籽油和花生油有较好的抗氧化作用;对金黄色葡萄球菌、大肠杆菌、黄曲霉和啤酒酵母抑制效果明显,其最低抑菌浓度分别为2%、3%、1%、1%,但对枯草芽孢杆菌和米曲霉抑制作用较弱;红花油茶籽油的抑菌活性不受温度的影响,对热稳定性良好;而pH的影响较为复杂,对大肠杆菌和黄曲霉的抑制效果与pH变化无关,但对啤酒酵母和金黄色葡萄球菌的抑制作用以酸性条件较好。     

红松松塔多糖抗氧化活性的研究

松塔多糖的提取采用传统的水提醇沉法,抗氧化性评价分别考察松塔多糖对ABTS自由基、羟基自由基和超氧阴离子的清除作用.结果表明,红松松塔多糖对于ABTS自由基和羟基自由基的清除效果要好于超氧阴离子,当多糖浓度达到30mg/mL的时候,对于ABTS自由基和羟基自由基的清除率分别达到了90.42％和90％,而对于超氧阴离子的清除率未能达到50％.红松松塔多糖具有较强的抗氧化功能.     

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.     

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.     

Aroma characterization of various apricot varieties using headspace–solid phase microextraction combined with gas chromatography–mass spectrometry and gas chromatography–olfactometry

The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.     

Tests of potential functional barriers for laminated multilayer food packages. Part I: Low molecular weight permeants

The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.     

Analysis of benzo[a]pyrene in spiked fatty foods by second derivative synchronous spectrofluorimetry after microwave-assisted treatment of samples

A simple, rapid and inexpensive method has been developed for the determination of benzo[a     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. II: Certification study

This paper describes the second part of a project undertaken to develop certified mussel reference materials for paralytic shellfish poisoning toxins. In the first part two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin and decarbamoyl-saxitoxin in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the certification exercise. Fifteen laboratories participated in this certification study and were asked to measure saxitoxin and decarbamoyl-saxitoxin in rehydrated lyophilized mussel material and in a saxitoxin-enriched mussel material. The participants were allowed to use a method of their choice but with an extraction procedure to be strictly followed. The study included extra experiments to verify the detection limits for both saxitoxin and decarbamoyl-saxitoxin. Most participants (13 of 15) were able to meet all the criteria set for the certification study. Results for saxitoxin.2HCl yielded a certified mass fraction of <0.07 mg/kg in the rehydrated lyophilized mussels. Results obtained for decarbamoyl-saxitoxin.2HCl yielded a certified mass fraction of 1.59+/-0.20 mg/kg. The results for saxitoxin.2HCl in enriched blank mussel yielded a certified mass fraction of 0.48 +/- 0.06 mg/kg. These certified reference materials for paralytic shellfish poisoning toxins in lyophilized mussel material are the first available for laboratories to test their method for accuracy and performance.     

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     

Chinese CTP Market

According to Printing and Printing Equipment Industries Association of China（PEIAC）＇s statistics to the plate manufucturer in China, in 2013, the actual offset plate production has reached 346 million square meters in China. Among them, the CTP production volume was 245 million square meters, up by 11% than that of last year; the total sales of the CTP plate was 239 million square meters, up by 13%.     

Preparatory Work of Print China 2015 is Going Smoothly

正Held at Guangdong Modern International Exhibition Center,Print China 2015 will cover 7exhibition halls,besides the original Hall No.3,4,5,6,7,the newly built F zone of Hall 3 will be used too.The total area will be140,000 square meters.Hall 3:Offset and large printing equipment,package printing equipment,post press