核桃虾青素复合油体外抗氧化活性研究

摘要：以特丁基对苯二酚（TBHQ）为阳性对照,通过测定核桃虾青素复合油（纯核桃油+2%虾青素油）对DPPH自由基（DPPH·）、羟自由基（·OH）、超氧自由基（O-2·）清除能力和还原能力以及Fe2+螯合能力,探讨复合油的体外抗氧化活性。结果表明：核桃虾青素复合油对DPPH·、O-2·、·OH的清除能力,还原能力和Fe2+螯合能力随着核桃虾青素复合油质量浓度的增加而升高,且对DPPH·、O-2·、·OH的清除能力均强于纯核桃油,对DPPH·、O-2·、·OH的半抑制质量浓度（IC50）分别为8.25、0.81、1.30 mg/mL;还原能力方面表现为添加TBHQ的核桃油>核桃虾青素复合油>纯核桃油;核桃虾青素复合油的Fe2+螯合能力明显强于纯核桃油和添加TBHQ的核桃油。研究表明核桃虾青素复合油较纯核桃油的体外抗氧化活性有所增强。     

天然抗氧化剂对鳄鱼油体外抗氧化活性的影响

为了筛选天然抗氧化剂和提高鳄鱼油体外抗氧化活性,采用Schaal烘箱法,比较3种常见的天然抗氧化剂茶多酚（TP)、维生素E和植酸对精制鳄鱼油的抗氧化效果,并优选出了天然抗氧化剂。在此基础上以优选抗氧化剂和VC为阳性对照,采用体外抗氧化法考察添加优选抗氧化剂的鳄鱼油对DPPH自由基、羟自由基（·OH）、超氧自由基（O-2·）清除能力,还原能力及Fe2+螯合能力。结果表明：3种天然抗氧化剂对鳄鱼油的抗氧化效果为TP＞维生素E＞植酸;鳄鱼油对DPPH自由基、·OH、O-2·清除能力,还原能力和Fe2+螯合能力均随其质量浓度的增加而升高;添加0.02%TP后鳄鱼油的体外抗氧化活性明显增强,添加TP的鳄鱼油对DPPH自由基、·OH和O-2·的IC50分别为0.874、0.064 mg/mL和0.96 mg/mL,均低于鳄鱼油的（5.448、0.684、4.53 mg/mL）,而还原能力和Fe2+螯合能力均高于鳄鱼油的。综上,TP可有效提高鳄鱼油的体外抗氧化活性。     

黄茶多糖的分离纯化及其抗氧化活性研究

该文对黄茶进行分离纯化,并对其抗氧化活性进行研究。对黄茶进行热水浸提、70%乙醇醇沉得到黄茶70部位的粗多糖（YT70）,利用阴离子交换柱对YT70进行分离纯化得到YT70-1,进一步对YT70-1进行DPPH·、ABTS+·、·OH的清除试验以及总还原力能力测定试验。结果表明YT70的糖含量为43.3%,YT70-1的单糖组成为甘露糖、鼠李糖、葡萄糖醛酸、葡萄糖、半乳糖、木糖、阿拉伯糖及岩藻糖。YT70-1对DPPH·、ABTS+·和·OH的清除率与质量浓度呈量效关系,且总还原能力与浓度成正比。在浓度为20 mg/mL时,YT70-1对DPPH·、ABTS+·和·OH的清除率分别为48.7%、77.01%和39.67%,还原力为0.415。YT70-1对ABTS+·的IC50值为3.87 mg/mL。因此YT70-1具有一定的体外抗氧化活性,能够清除DPPH·、ABTS+·和·OH,并且清除能力随多糖浓度的增大而增加。     

动态高压微射流辅助提取对鱼鳞多糖抗氧化活性的影响

采用动态高压微射流技术辅助提取鲤鱼鱼鳞多糖,以DPPH·、·O₂-、ABTS+·、·OH清除能力和Fe3+还原能力为评价指标,研究其对鲤鱼鱼鳞多糖抗氧化活性的影响。结果表明:动态高压微射流处理可以有效降低物料的平均粒度,粒径由未经处理的499.80 nm降低到192.57 nm;进而提高鲤鱼鱼鳞多糖的得率,当处理压力为130 MPa时,多糖得率达到7.81%。随着处理压力的提高,多糖提取液对DPPH·、·O₂-、ABTS+·和·OH的清除率以及Fe3+的还原能力逐渐增强,当处理压力为110 MPa时,DPPH·、·O₂-、·OH的清除率和Fe3+的还原能力最高分别达到了86.04%、61.23%、90.59%和0.64(OD值),当处理压力为150 MPa时,对ABTS+·的清除率达到89.58%,均显著高于空白对照组(P<0.05)。动态高压微射流辅助提取可以有效提高鲤鱼鱼鳞多糖的得率和体外抗氧化能力,本研究可为动态高压微射流技术在天然活性多糖辅助提取方面的应用提供理论依据和技术支撑。     

大口黑鲈鱼皮胶原蛋白肽的制备及抗氧化活性研究

目的：探究酶种类对胶原蛋白肽抗氧化活性的影响。方法：从大口黑鲈(Micropterus salmoides)鱼皮中提取胶原蛋白,采用碱性蛋白酶、中性蛋白酶、木瓜蛋白酶和胰蛋白酶酶解胶原蛋白,得到碱性蛋白酶酶解胶原蛋白肽(APP)、中性蛋白酶酶解胶原蛋白肽(NPP)、木瓜蛋白酶酶解胶原蛋白肽(PP)、胰蛋白酶酶解胶原蛋白肽(TP),比较其总抗氧化活性、还原活性、对DPPH·、·OH 和O-2·清除能力以及亚铁离子螯合能力和脂质氧化抑制活性。结果：4种蛋白酶酶解胶原蛋白肽都具有抗氧化活性,且抗氧化能力与胶原蛋白肽浓度呈正相关,其中APP的抗氧化活性最佳,总抗氧化活性和还原活性分别为1.725和0.958,对DPPH·和O-2·清除率分别为56.35%和38.41%。结论：碱性蛋白酶酶解的胶原蛋白肽抗氧化活性更佳。     

3种己糖糖基化修饰对豌豆蛋白结构和抗氧化活性的影响

目的 探究3种己糖糖基化修饰对豌豆蛋白结构和抗氧化活性的影响。。方法 通过自由氨基含量测定、内源荧光及表面疏水性变化、ABTS+·清除能力、DPPH·清除率、Fe2+螯合能力和超氧阴离子自由基清除能力分析研究豌豆蛋白糖基化产物的结构和 抗氧化活性。结果 经糖基化处理后,豌豆蛋白的自由氨基含量降低,空间结构发生改变,其中以半乳糖制备的豌豆蛋白糖基化产物（Pea protein-galactose conjugated compound,PP-gal）糖基化程度最大。就抗氧化性而言,PP-gal具有更好的ABTS+·清除能力、DPPH·清除率、Fe2+螯合能力和超氧阴离子自由基清除能力,即抗氧化活性最强。结论 本研究可为具有良好抗氧化活性的豌豆蛋白制备提供参考。     

油茶籽粕多糖不同分子修饰产物的抗氧化活性

为比较不同修饰方法对油茶籽粕多糖抗氧化活性的影响,通过硫酸酯化、羧甲基化及乙酰化3种方法对纯化的油茶籽粕多糖(COP)进行分子修饰,以制备具有不同取代度的COP。采用体外实验法,以羟自由基(·OH)、超氧阴离子自由基（·O-2）及DPPH自由基(DPPH·)清除率为指标,探究COP及其分子修饰产物的抗氧化活性。结果表明：较低取代度的硫酸酯化修饰能提高COP对·OH、·O-2以及DPPH·的清除能力;高取代度的羧甲基化修饰能提高COP对·OH的清除能力,低取代度的羧甲基化修饰则能提高COP对DPPH·的清除能力;高取代度的乙酰化修饰COP对·OH和DPPH·的清除效果更好;羧甲基化修饰和乙酰化修饰COP均会削弱其对·O-2的清除能力。总之,适度的分子修饰能提高COP的抗氧化活性。     

近江牡蛎糖胺聚糖的抗氧化活性及其稳定性

以近江牡蛎全脏器为原料,通过酶解法得到近江牡蛎糖胺聚糖,通过测定羟自由基(·OH)和1-二苯基-2-三硝基苯肼自由基(DPPH·)清除率探讨其抗氧化能力,并分析不同温度、pH、紫外照射、NaCl浓度以及模拟胃肠道消化对近江牡蛎糖胺聚糖抗氧化稳定性的影响。结果表明,近江牡蛎糖胺聚糖具有较好的体外抗氧化活性,DPPH·的清除率达到79.15%,·OH清除率达到了100.00%。近江牡蛎糖胺聚糖在温度为40~80℃、偏酸环境、紫外线照射下、或Na+存在的条件下仍保持较好的抗氧化活性。经模拟胃肠消化后,糖胺聚糖但仍具有一定的清除能力,DPPH·清除率为26.43%,·OH清除率为10.07%。因此,近江牡蛎糖胺聚糖具有较好的抗氧化能力,是一种相对稳定的天然抗氧化剂。     

文冠果果壳总皂苷的提取工艺优化及抗氧化、抗肿瘤活性评价

文冠果果壳是文冠果生产过程中产生的废弃物,该研究以文冠果果壳为原料,采用单因素结合响应面法优化超声细胞破碎法提取文冠果果壳总皂苷的工艺条件,以DPPH·清除率、ABTS+·清除率及Fe2+螯合能力为指标评价总皂苷提取物的抗氧化活性,用CCK-8法分析总皂苷提取物对HepG2和A549细胞增殖的抑制效果。结果表明,文冠果果壳总皂苷最佳提取条件为：乙醇体积分数65%、液料比35:1（mL/g）、超声功率200 W、超声时间35 min、超声温度50 ℃,总皂苷得率可达14.95 mg/g。抗氧化实验结果表明总皂苷提取物浓度为0.05 mg/mL,对DPPH·、ABTS+·的清除率分别为91.35%、82.63%;浓度为0.10 mg/mL,对Fe2+螯合能力为88.01%;总皂苷提取物浓度与ABTS+·清除能力、Fe2+螯合能力呈极显著相关（p<0.01）。抗肿瘤结果表明总皂苷提取物浓度为 120 μg/mL,作用于HepG2细胞和A549细胞的细胞存活率分别为10.95%和2.04%,其IC50值分别为79.30 μg/mL和63 μg/mL。综上可知,超声细胞破碎法是一种高效的制备文冠果果壳总皂苷的技术,文冠果果壳总皂苷提取物具有良好的抗氧化、抗肿瘤活性,该研究可为文冠果废弃物的有效开发利用提供方法学借鉴。     

蟛蜞菊总黄酮的超声波辅助提取工艺优化及其抗氧化能力的研究

以蟛蜞菊为研究对象,采用超声波辅助提取蟛蜞菊总黄酮,确定蟛蜞菊总黄酮的最佳提取工艺条件,并对其抗氧化能力进行探究。结果显示,蟛蜞菊总黄酮的最佳提取条件为：乙醇浓度45%,料液比1∶30（g/mL）,超声功率40 W,提取温度60℃,提取时间40 min,此条件下,蟛蜞菊总黄酮的得率高达6.64%。蟛蜞菊总黄酮的抗氧化能力结果表明,蟛蜞菊总黄酮提取液的质量浓度越大,对·OH、DPPH·以及NaNO2的清除能力就越强。当蟛蜞菊总黄酮的质量浓度为0.664 mg/mL时,对DPPH·、·OH、NaNO2的清除率分别为94.62%、76.29%、63.99%,即DPPH·的清除率＞·OH的清除率＞NaNO2的清除率。由此可见,蟛蜞菊总黄酮具有较好的抗氧化活性。     

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.     

Chlorohydrins of bisphenol A diglycidyl ether (BADGE) and of bisphenol F diglycidyl ether (BFDGE) in canned foods and ready-to-drink coffees from the Japanese market

BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H₂O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.     

European priorities for research to support legislation in the area of food contact materials and articles

A strong science base is required to underpin the planning and decision-making process involved in determining future European community legislation on materials and articles in contact with food. Significant progress has been made in the past 5 years in European funded work in this area, with many developments contributing to a much better understanding of the migration process, and better and simpler approaches to food control. In this paper this progress is reviewed against previously identified work-areas (identified in 1994) and conclusions are reached about future requirements for R&D to support legislation on food contact materials and articles over the next 5 or so years.     

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.     

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.     

Influence des ions sur le pouvoir hydratant de l'ure e: e tude sur peau de porc ex vivo

This study deals with the influence of ions (NaCl and MgSO4) in a W/O emulsion containing 10% urea. Moisturization kinetics are assessed by corneometry on pig skin ex vivo. The formula's influence on urea penetration is measured by infrared spectrometry with an ATR device and the stripping method. Corneometry and spectroscopy were chosen to record simultaneously the hydratation levels and urea localization into superficial cell layers. Urea crystallization after evaporation of emulsions and aqueous solutions is described. Results show that urea does not hydrate nor penetrate when applied to the skin through an aqueous gel. In a W/O emulsion, sodium chloride increases the ability of urea to moisturize without improving penetration. In vitro urea crystallization is disturbed by sodium chloride or magnesium sulphate for solutions and emulsions. This stabilization by ions is correlated with good moisturization values. The stabilization of urea in the solute state provided by ions increases its water epidermal binding capacity without enhancing penetration.     

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.     

Analysis on Economic Indicators from 62 Enterprises in Printing Machinery Industry in Q1 2014

Operation of printing machine industry was still unsatisfactory in the first quarter of 2014.Analysis on operation of printing machine industry.a.Market demand was not strong;sales of product undulated and declined.According to the statistics,the total industrial output value fell by 19.28% in the first quarter of 2014 than the average quarter value in 2013; industrial added value decreased by 4.16%; sales revenue dropped by 22.83%. h. Business operation of enterprises was in poor condition. c. R＆D of new products is an important transformation guarantee for enterprises. d. To take self explore new ways upgrading advantages,and explore new ways.