9个品种番石榴果实提取物抗氧化活性比较研究

目的 分析比较9个品种番石榴果实的抗氧化活性,为筛选适合开发天然抗氧化产品的番石榴优良品种提供理论依据。方法 测定‘紫色’‘红宝石’‘粉红蜜’‘西瓜’‘珍珠’‘帝王’‘翠玉’‘水蜜’‘本土’9个品种番石榴醇提物和水提物的总酚、黄酮含量,研究其对2,2’-联氮-双(3-乙基苯并噻唑啉-6-磺酸)二铵盐[2,2’-azino-bis（3-ethylbenzothiazoline-6-sulfonicacid）ammonium salt, ABTS]、1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl, DPPH）自由基清除能力和总抗氧化能力,利用抗氧化能力综合指数评价不同样品的抗氧化活性,并分析总酚、黄酮含量与抗氧化活性的相关性。结果 9个品种番石榴醇提物总酚和黄酮含量分别为1.363~2.394 g/100 g和0.607~1.875 g/100 g,对DPPH、ABTS自由基的半数清除浓度（medium inhibition concentration, IC50）分别为0.242~0.518 mg/mL和1.990~4.929 mg/mL,总抗氧化能力为0.113~0.206 mmol/g;水提物总酚和黄酮含量则为1.192~2.142 g/100 g和0.393~1.118 g/100 g,对DPPH、ABTS自由基的IC50分别为0.320~0.661 mg/mL和2.837~5.472 mg/mL,总抗氧化能力为0.105~0.181 mmol/g。水提物和醇提物的总酚、黄酮含量均以‘紫色’番石榴最高,抗氧化能力综合指数也以‘紫色’最高。除‘水蜜’外,其他品种醇提物的抗氧化活性均高于水提物。相关性分析结果显示,总酚、黄酮含量与DPPH自由基清除能力、ABTS自由基清除能力、总抗氧化能力和抗氧化能力综合指数呈正相关关系。结论 9个品种番石榴的提取物中,‘紫色’醇提物的总酚、黄酮含量和抗氧化活性最高,是开发天然抗氧化产品的最佳来源。     

干燥方法对番石榴活性物质含量及抗氧化能力的影响

为研究干燥方式、工艺参数对番石榴活性物质含量及抗氧化能力的影响,采用热风干燥、热风-红外联合干燥、真空干燥和真空冷冻干燥技术,比较其对番石榴总酚、黄酮、抗坏血酸含量、清除1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基能力、清除2,2’-联氮-二（3-乙基苯并噻唑啉-6-磺酸）二铵盐（2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)diammonium salt,ABTS）自由基能力和铁离子还原能力（ferric reducing antioxidant power,FRAP ）以及抑制亚油酸过氧化能力的影响。结果表明,与鲜果相比,干燥后番石榴总酚含量显著增加,黄酮和抗坏血酸含量显著降低（P＜0.05）,抗氧化能力显著降低。真空干燥和真空冷冻干燥得到的总酚、抗坏血酸含量较高,清除自由基及FRAP较高。热风干燥得到的番石榴干制品抑制亚油酸过氧化能力较高。随干燥温度升高,热风和热风-红外联合干燥后的黄酮保留量增加,抗坏血酸含量、清除自由基及FRAP降低。综合来看,真空冷冻干燥和中低温热风干燥（60 ℃和75 ℃）得到的番石榴干制品抗氧化能力较高。Spearman相关性分析表明,DPPH、ABTS、FRAP法测定的抗氧化能力及抗氧化效能综合指数分别与总酚含量的相关系数较高,且DPPH自由基清除能力、抗氧化效能综合指数与总酚含量呈显著正相关（P＜0.05）,说明多酚可能是番石榴干制品主要抗氧化物质。     

番石榴叶中黄酮类物质提取及其抗氧化性研究

研究了番石榴叶中黄酮类物质的提取工艺,并用正交实验确定了最佳的提取条件.实验结果表明:番石榴叶中总黄酮类物质的最佳提取条件为原材料经过微波处理3 min,再用40%的乙醇回流3 h,此条件下黄酮得率为9.91%.抗氧化实验表明,番石榴叶黄酮提取物能有效抑制猪油的氧化,对羟自由基和超氧自由基有良好的清除作用.     

金线莲不同器官及萃取部位的抗氧化活性研究

采用DPPH和ABTS+法比较金线莲黄酮和多酚含量与抗氧化活性的相关性。将金线莲不同器官乙醇提取物经石油醚(PEE)、乙酸乙酯(EAE)和正丁醇(NBE)依次萃取。结果显示,不同器官的同一萃取层中,黄酮和多酚含量为叶全草茎根状茎及根。同一器官不同萃取层中,黄酮含量为EAEPEENBEWE,多酚含量为NBEEAEWEPEE。其体外抗氧化试验结果表明,叶对自由基的清除能力显著高于其它器官,根状茎及根的清除能力最弱。正丁醇层对自由基的清除能力最强,石油醚层的清除力最弱,抗氧化能力为NBEEAEWEPEE。金线莲中的多酚含量与抗氧化活性呈显著正相关,而黄酮含量与抗氧化活性无显著相关性。     

20种花茶黄酮、总酚及抗氧化活性分析

为评价20种市售花茶的黄酮、总酚含量及抗氧化活性,该研究模拟日常饮茶,采用水提法对活性成分进行提取,测定黄酮、总酚含量,通过测定羟基自由基（·OH）、DPPH自由基和ABTS＋自由基的清除作用研究不同花茶的抗氧化能力,利用相关系数法分析黄酮、总酚与抗氧化活性的相关性。结果表明：20种花茶黄酮含量为0.15 mg/g～5.35 mg/g,总酚含量为4.57 mg/g～31.02 mg/g,不同花茶之间黄酮和总酚含量差异显著（P＜0.05）。其中蒲公英的黄酮和总酚含量最高,千日红最低。综合评价20种花茶的抗氧化能力,排在前5位的依次为蒲公英、苦丁、薄荷花茶、荷叶和牡丹花茶。抗氧化综合评价值和总酚、黄酮的相关系数分别为0.956和0.798,表明总酚含量和花茶的抗氧化能力相关性更强,总酚对花茶的抗氧化性有较多贡献。     

浸泡时间对绿豆浸泡液中多酚及抗氧化活性的影响

研究了不同浸泡时间对绿豆浸泡液中多酚、黄酮、DPPH自由基清除能力、ABTS+·自由基清除能力、总抗氧化能力的影响,分析了多酚、黄酮含量与抗氧化能力之间的相关性。结果表明:浸泡时间在4~12 h内,随着浸泡时间的增加,浸泡液中多酚、黄酮含量显著增加,ABTS+·自由基清除能力、DPPH自由基清除能力显著增强,浸泡12 h后,增长趋势渐缓;总抗氧化能力在4~8 h内,随浸泡时间的增加而快速增大,之后保持缓慢增长,24 h时总抗氧化能力达到最大;多酚、黄酮含量与抗氧化能力之间具有显著的相关性(P0.01)。     

马铃薯抗氧化活性成分研究

分析了宁夏地区种植的8种马铃薯总酚、总黄酮含量,并采用高效液相色谱法测定马铃薯中酚酸种类及其含量;通过体外抗氧化评价模型比较8种马铃薯对超氧阴离子、羟基自由基、DPPH自由基、ABTS自由基清除能力及FRAP铁还原能力。结果表明:黑美人总酚含量最高,为400.38 mg/100 g,夏波蒂总酚含量最低,为233.93mg/100g;费乌瑞它黄酮含量最高,为107.39mg/100g,庄薯3号黄酮含量最低,为33.17mg/100g;所有品种马铃薯的主要酚酸物质均为绿原酸,其中黑美人含量最高(91.46%);绿原酸含量与酚酸、黄酮含量呈极显著正相关性(P0.01);酚酸含量与ABTS自由基清除能力相关性最大;黄酮含量与羟基自由基清除能力呈极显著负相关(P0.01);绿原酸含量与ABTS自由基清除能力相关性最大。     

白肉番石榴总黄酮提取工艺优化及体外抗氧化活性分析

对白肉番石榴中总黄酮的提取工艺进行优化,并研究其体外的抗氧化活性。以珍珠番石榴(白肉)的叶、皮为原料,在单因素实验的基础上,以总黄酮提取量为指标,采用正交试验优化获得了番石榴叶、皮中总黄酮的提取工艺。在此基础上提取番石榴果肉中的总黄酮,然后比较番石榴叶、皮、果肉中黄酮的体外抗氧化作用。结果表明,番石榴叶、皮的总黄酮的最优提取工艺略有差异。番石榴叶总黄酮的提取最优工艺为:乙醇浓度50%,提取温度65 ℃,料液比1:20 (g/mL),提取时间135 min。番石榴皮总黄酮提取最优工艺为:乙醇浓度60%,提取温度45 ℃,料液比1:7 (g/mL),提取时间105 min。在最优条件下番石榴叶、皮总黄酮的提取量分别为(188.66±0.23)、(48.03±0.16) mg/g。番石榴叶、皮、果肉总黄酮在ABTS自由基及羟基自由基清除实验、铁还原力及总抗氧化力测定分析中显示良好的抗氧化活性,其中番石榴叶总黄酮的体外抗氧化能力最强。由此说明番石榴黄酮有望成为一种良好的天然抗氧化剂。     

番石榴多酚体外抗氧化活性的研究

微波辅助提取的番石榴多酚粗提物经过NKA-9大孔吸附树脂初步纯化和Sephadex LH-20葡聚糖凝胶的分离,得到四个不同组分(GP1、GP2、GP3、GP4)。以抗坏血酸(V C)为阳性对照,采用总抗氧化能力、羟自由基、超氧阴离子自由基和DPPH自由基四种体外抗氧化能力评价体系测定了番石榴粗多酚(CGP)、大孔吸附树脂纯化多酚(PGP)和各分离组分的抗氧化能力。结果表明:番石榴多酚具有很高的抗氧化活性,总抗氧化能力大小为GP4>V C>GP3>GP2>PGP>CGP>GP1。番石榴多酚能有效地清除羟自由基、超氧阴离子自由基和DPPH自由基,在一定范围内清除自由基能力和浓度成线性关系。     

连翘叶不同溶剂提取物体外抗氧化活性研究

比较连翘叶不同提取溶剂提取物的抗氧化活性。分别以水、60%乙醇、80%乙醇、无水乙醇、乙酸乙酯为溶剂制备连翘叶提取物,测定不同提取物中多糖、总酚和黄酮含量;以BHT为阳性对照,采用DPPH自由基(DPPH·)、羟基自由基(·OH)、超氧阴离子(O_2~-·)、ABTS自由基(ABTS~+·)清除活性和铁离子还原能力(FRAP)法考察各溶剂提取物的抗氧化活性;考察提取物中活性物质含量与其活性的相关性。连翘叶不同溶剂提取物均具有抗氧化活性,均呈一定的量效关系,且不同溶剂提取物的抗氧化活性强弱顺序随评价方法的不同而不同。连翘叶不同溶剂提取物中总酚含量和黄酮含量均与·OH清除活性和铁离子还原能力具有较高的相关性,黄酮含量还与O_2~-·清除活性具有较高的相关性。连翘叶80%乙醇提取物和60%乙醇提取物抗氧化活性相对较高。     

蛋白质水解度测定方法综述

对目前国内外常用的蛋白质水解度测定方法进行了综述，其中pH—state方法是通过滴定水解过程中释放的质子测定DH；OPA、TNBS及国内常用的水合茚三酮和甲醛等测定方法是利用游离氨基的反应测定DH。     

BASIS OF STABILITY OF AMINE SALTS OF LINOLEIC ACID

SUMMARY— The mechanism and generality of the known stabilization against autoxidation conferred on linoleic acid by certain basic amino acids, such as lysine and arginine, was investigated. Basic amino acids were the only class of compounds found to confer the effect. However, the smallest basic amino acid, 2,3-diaminopropionic acid, was not effective, nor was αβω-diaminc acid, 3,6-diaminohexanoic acid, although a simple isomer of lysine. The stabilization was observed only in the solid phase. Inclusion of sodium chloride in the solid matrix was deleterious to the effect. A large number of physical and chemical observations were made and correlated but it has not been possible to draw detailed conclusions about the mechanism of stabilization, nor can a detailed structure of the stabilized complex be suggested. The cause of the phenomenon appears to be closely associated with the physical arrangement of the ions in the crystal lattice.     

百年风尚

一场流光溢彩、赏心悦目的展览,一段百年风尚演进的传奇旅程,一次东西方文化艺术的完美对话。2013年9月13日,“博萃臻艺一中西方珍宝艺术展”在辽宁省博物馆举行了隆重的开幕仪式,法兰西共和国驻华大使白林女士、辽宁省文物局局长丁辉先生、辽宁省博物馆馆长马宝杰先生、卡地亚全球总裁兼首席执行官邓阁仕先生、卡地亚区域行政总裁（北亚洲）陆慧全先生、卡地亚中国区首席执行官陆意斯先生、辽宁省文物店总经理张春鹰先生,以及众多文化界与文博界的贵宾齐聚一堂,共同见证了这场文化艺术盛事。     

EFFECTS OF TYPES OF FAT AND OF RATES AND TEMPERATURES OF COMMINUTION ON DISPERSION OF LIPIDS IN FRANKFURTERS

ABSTRACT— The effect of time, temperature and rpm of comminution of emulsions was determined on the dispersion of approximately 25% of beef fat, pork fat or cottonseed oil in frankfurters. The numbers of lipid particles 5 μ or less in diameter increased in frankfurters containing either beef or pork fat as comminution was continued to higher temperatures, with pork fat dispersed more thoroughly. Fat tended to separate from frankfurters containing beef fat in particles 200 μ or more in diameter. In contrast, no specific degree of dispersion of particles 5 μ or less in diameter consistently indicated emulsion stability, or its lack. Increased rpm during comminution produced an increased dispersion of beef or pork fat. Under the same conditions pork fat was dispersed more finely than beef fat. Dispersion of cottonseed oil produced finely dispersed particles beyond the resolution of light microscopy, as was confirmed by electron microscopy which showed a substantial number of particles to be less than 1 μ in diameter.     

SEROLOGIC IDENTIFICATION OF SPECIES OF ORIGIN OF SAUSAGE MEATS

SUMMARY: A partially purified immunoglobulin G (lgG) solution prepared from the serum of species to be tested was heated to the specifications for sausages. The resulting supernatant fluid was decanted and the precipitate washed with saline and used to immunize rabbits. The supernatant fluid was used to sensitize tanned sheep red blood cells. The immune serum was rendered monospecific by absorptions with heterologous, heated lgG precipitates. A sample of monospecific immune serum was absorbed with a washed homogenate of sausage. Aliquots of the monospecific immune serum, both untreated and sausage absorbed, were tested with cells sensitized with the homologous heated lgG supematant fluid. A significant reduction of titer by sausage absorption indicated that the sausages contained the meat homologous to the immune serum.     

DEVELOPMENT OF CHAINS OF CELLS OF SACCHAROMYCES CEREVISIAE DURING FERMENTATION

The lengths of chains of cells of Saccharomyces cerevisiae were studied during fermentation. Pitching yeast generally contained about half of the total number of cells as two-celled chains. The chain lengths varied during the subsequent fermentation and the variations were characteristic of the strain. Electronic counting assessments of chain length were unreliable.     

聚多元羧酸盐的合成及应用

研究了聚多元羧酸盐的合成方法及反应机理,将其应用于洗涤剂和PVC制品中分别代替三聚磷酸钠和邻苯二甲酸二丁酯,证明有良好效果。     

矩阵乘积的行式,列式

给出了ｍ×ｍ矩阵与ｍ×ｎ矩阵的行（列）式的表达式．若Ａ＝ａ１１ａ１２…ａ１ｍａ２１ａ２２…ａ２ｍ……ａｍ１ａｍ２…ａｍｍＢ＝ｂ１１ｂ１２…ｂ１ｎｂ２１ｂ２２…ｂ２ｎ……ｂｍ１ｂｍ２…ｂｍｎ分别是ｍ×ｍ，ｍ×ｎ矩阵，则｜Ａ｜｜Ｂ｜＝｜ＡＢ｜＋∑ｉ１＜ｉ２＜…＜ｉｔｊ１＜ｊ２＜…＜ｊｔ１≤ｔ≤ｍｎ－ｔ≥ｍＮＢｉ１ｉ２…ｉｔｊ１ｊ２…ｊｔＮＡＢ１…ｍ（－１）ｓｔ＋１ｊｔ＋１…（－１）ｓｎｊｎ其中ｉ１，ｉ２，…，ｉｔ是１，２，…，ｍ中ｔ个数码；ｊ１，ｊ２，…，ｊｔ，ｊｔ＋１，…，ｊｎ是１，２，…，ｎ的一个排列；ｓｒ＝π（ｊ１，ｊ２，…，ｊｔ，ｊｒ）（ｒ＝１，２，…，ｎ）是排列ｊ１，ｊ２，…，ｊｔ，ｊｒ的反序数．     

山药水溶性多糖的提取及抗氧化性研究

研究山药水溶性多糖的提取及其抗氧化作用。方法是将小鼠分别口服给予山药水溶性多糖，每天1次，连续给药15d，取血测过氧化物酶（POD）活性，取血、肝、肾测超氧化物歧化酶（sOD）活性，脂质过氧化产物（MDA）含量。山药多糖物可显著提高POD活性及血、肝、肾的SOD活性，并减少血、肝、肾组织中MDA的含量。山药水溶性多糖有提高小鼠体内过氧化物酶、超氧化物歧化酶活性及减少脂质过氧化产物的抗氧化作用。     

ANALYTICAL CHARACTERIZATION OF THE PRODUCTS OF NONENZYMATIC GLYCOSYLATION OF LYSOZYME

The quantitative analysis of the reaction products of the water activity dependent nonenzymatic glycosylation of lysozyme was not straightforward. Difficulties arose in the determination of the number of bound glucose molecules because glycosylation leads to glucose mediated protein aggregation, and the likely presence of a mixture of relatively labile Schiff-base intermediates, and the more stable ketoamine products generated by Amadori rearrangement. Polyacrylamide gel electrophoresis was used to monitor protein aggregation; periodate oxidation, nuclear magnetic resonance (NMR), and oxalic acid hydrolysis combined with HPLC, emerged as the most promising methods to quantitate the degree of glycosylation. Possible interpretations are advanced to explain the apparent discrepancies in degree of glycosylation suggested by the different analytical methods evaluated.