粮油食品中黄曲霉毒素去除方法研究进展

黄曲霉毒素广泛存在于粮油食品中,给全球农作物生产造成巨大经济损失。黄曲霉毒素具有极强的毒性和致癌性,严重威胁着人类的健康,迫切需要寻找一种有效、安全、环保控制黄曲霉生长或降解黄曲霉毒素的方法。对物理方法、化学方法和生物方法抑制黄曲霉生长或降解黄曲霉毒素的研究进行了综述。     

酱油中黄曲霉毒素B1的测定意义及测定方法比较

黄曲霉毒素是一种真菌毒素，其存在严重影响农作物的产量及农产品的质量。酱油产品无论在原料上还是在工艺上都有感染黄曲霉毒素的可能性。食品质量安全市场准入制度也将黄曲霉毒素列为酱油产品的必检项目。本文阐述了黄曲霉毒素的测定意义，并将国标中两种测定方法进行比较，供同行参考。     

ThermoFisher Scientific检测食品中五种黄曲霉毒素的完整解决方案

黄曲霉毒素因具有致癌性及强急性毒性,所以在食品和农产品贸易中为必检项目,尤其经过蒙牛乳制品中黄曲霉毒素M1超标事件后,人们对黄曲霉毒素的关注愈来愈热.黄曲霉毒素是霉菌的二级代谢产物,目前主要关注的黄曲霉毒素有黄曲霉毒素B1、B2、G1、G2、M1,其中黄曲霉毒素B1的毒性和致癌性最强,而黄曲霉毒素M1是黄曲霉毒素B1的代谢物.我国规定,乳品及乳制品中黄曲霉毒素M1限量为0.5μg/kg,粮食中黄曲霉毒素B1为10μg/kg.     

乳酸菌对乳制品中黄曲霉毒素的生物防治作用

黄曲霉及其毒素污染常发生于乳制品中,导致一定的经济损失,且严重危害人体健康。乳酸菌及其代谢产物均可有效地吸附去除黄曲霉毒素。就黄曲霉毒素、乳酸菌生物防治作用、乳酸菌对乳制品中黄曲霉毒素生物防治作用的应用及安全性评价进行综述,为提高我国发酵乳制品的卫生安全质量提供理论依据。     

茶叶中黄曲霉毒素的安全性风险研究进展

茶叶是世界上最流行的饮品之一,因其独特的风味和对人体有益的健康功能为人们所喜爱。茶叶在生长、采摘、加工、运输及储存过程中可能存在潜在的黄曲霉毒素污染,黄曲霉毒素是世界上已知毒性最大的真菌毒素,对人类健康存在极大威胁。黄曲霉毒素主要有四种常见的亚型,包括黄曲霉毒素B1,B2,G1,G2。其中黄曲霉毒素B1是毒性最大的黄曲霉毒素,被国际癌症研究机构列为Ⅰ类致癌物。因此评估茶叶中是否存在黄曲霉毒素及其安全性具有重要意义。本文系统地综述了黄曲霉毒素的理化性质、致病机理,以及茶叶中可能产黄曲霉毒素的微生物和黄曲霉毒素在茶叶中的检出情况等,并探讨茶叶中黄曲霉毒素的潜在风险,为茶叶中黄曲霉毒素的风险评估与防控提供支持。     

黄曲霉毒素的检测及其降解方法进展

黄曲霉毒素主要是由真菌寄生曲霉和黄曲霉产生的次生代谢产物,具有极强的毒性、致癌性,在自然界中普遍存在。文中论述了不同物质中黄曲霉毒素的检测方法及应用,同时介绍了黄曲霉毒素的降解方法及成果,并对黄曲霉毒素检测及降解技术的发展趋势进行了展望。     

黄曲霉毒素检测技术的研究进展

黄曲霉毒素（AFT）检测方法和技术的了解与掌握对黄曲霉毒素快速，准确的检测有重要意义，本中介绍了黄曲霉毒素的几种常见检测方法，并对其特点及检出限进行了概括性的分析。     

含水量对玉米粉贮藏期黄曲霉生长及黄曲霉毒素B1积累的影响

目的 研究含水量对玉米粉贮藏过程中黄曲霉生长及黄曲霉毒素B1积累的影响。方法 将初始水分含量10.42%、13.26%、16.35%、19.88%的玉米粉在28 ℃, 相对湿度75%的模拟环境中储藏30 d; 测定贮藏期间玉米粉含水量、黄曲霉生长量及黄曲霉毒素B1的积累量。结果 贮藏期间玉米粉中含水量呈现先上升后下降的变化趋势, 黄曲霉生长量及黄曲霉毒素B1的积累量随贮藏时间的延迟先快速升高, 后趋于平稳。初始含水量较高的玉米粉贮藏期间含水量、黄曲霉生长量及黄曲霉毒素B1含量始终处于较高的水平。相关性分析表明, 玉米粉含水量、黄曲霉生长量和毒素积累量之间均呈极显著的正相关(P<0.01)。结论 含水量是影响玉米粉贮藏过程中霉菌生长和毒素积累的关键因素, 降低玉米粉初始含水量可以有效减轻贮藏期间真菌危害。     

黄曲霉毒素的产生机制及污染防控策略

黄曲霉是一种广泛分布的环境习居菌,经常在种植、贮藏、加工、运输过程污染玉米、花生等富含脂肪酸的粮食及相关食品和饲料,并会产生多种有毒次生代谢产物。其中,黄曲霉毒素是黄曲霉产生的最主要真菌毒素之一,是公认的一类致癌物。黄曲霉毒素污染严重影响农产品质量安全;带来巨大的经济损失和贸易争端;更重要的是,黄曲霉毒素具有高毒性、高致癌性、致突变性和免疫抑制性,严重威胁人畜健康。因此,黄曲霉毒素合成、调控及防控的相关工作一直是食品安全领域的研究重点和热点。阐述已知的黄曲霉毒素产生途径及相关调控机制,并介绍了多种有效的防控手段。重点讨论光照、温度、水活度、营养物质、pH值、氧化胁迫等环境因子对黄曲霉毒素合成的影响及已明确的调控机制;阐明了参与不同环境因子调控毒素合成的关键转录因子;同时分别从物理、化学和生物等不同技术层面介绍了多种有效抑制或降解黄曲霉毒素的方法,总结了黄曲霉毒素污染防控策略;并对今后的关键研究方向和重点防控措施做出了展望。     

牛奶中黄曲霉毒素的来源与控制

本文概述了牛奶中黄曲霉毒素的存在种类,来源及其性质.对近年来国内外对牛奶中黄曲霉毒素毒素的检测方法、控制和消除方法进行了研究.     

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。     

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.     

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。     

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.     

STABILITY OF AQUEOUS EMULSIONS OF THE ESSENTIAL OIL OF HOPS

Hop oil emulsions prepared from different varieties of hops have been found to exhibit enhanced physical stability on the addition of blends of the emulsifiers Span 20/Tween 80 or Span 60/Tween 60. Examination of the particle size and volume distributions of an emulsion by use of a Coulter Counter was found to be an excellent method of monitoring its stability. An indication as to the relative efficiency of emulsifiers can be obtained from Coulter Counter measurements on hop oil emulsions after storage for 4 days. The use of an ultracentrifuge provies a rapid means of testing emulsion stability and hence the effectiveness of emulsion stabilizers.     

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.     

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.     

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.     

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．