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乳铁素B是牛乳铁蛋白经胃蛋白酶酶解后得到的最重要的抗菌肽,具有较强抗菌活性.研究表明,乳铁素B对大肠杆菌的最小抑菌质量浓度为0.5mg/mL,对金黄色葡萄球菌的最小抑菌浓度为0.4mg/mL;葡萄糖、蔗糖、麦芽糖、牛血清白蛋白(BSA)、尿素、硫酸铵在0~10mg/mL,乳糖、可溶性淀粉在0~4mg/mL,的质量浓度范围内,对乳铁素B的抗菌活性影响不大;当NaCl或KCl的浓度为25~100mmol/L,MgCl2或CaCl2的浓度为1.0~5.0mmol/L时,乳铁素B的抗菌活性就会大大降低;随着缓冲盐浓度和有机酸浓度(25~100mmol/L)的增大,乳铁素B的抗菌活性呈下降趋势,且在微碱性环境下乳铁素B表现出较强的抗菌活力. 相似文献
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常用防腐剂对牛乳铁蛋白抗菌活性的影响 总被引:1,自引:0,他引:1
乳铁蛋白的抗菌活性常受到其他共存成分的影响。本文研究了常用防腐剂对乳铁蛋白抗菌活性的影响。在研究过程中,以大肠杆菌为实验菌株,进行了实验研究。研究表明,在牛肉膏蛋白胨培养基中,pH6.0,菌浓为106CFU/ml的条件下,乳铁蛋白对大肠杆菌的最小抑菌质量浓度为3mg/ml;苯甲酸钠、山梨酸钾、乳酸链球菌素、对羟基苯甲酸等分别与乳铁蛋白共同作用时,对乳铁蛋白的抗菌活性都有明显的影响。其中,山梨酸钾和苯甲酸钠减弱了乳铁蛋白的抗菌活性,乳酸链球菌素和对羟基苯甲酸丁酯加强了乳铁蛋白的抗菌活性。 相似文献
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本文对添加乳铁蛋白延长巴氏奶贮存时间进行了研究。乳铁蛋白是从牛初乳中分离出来的一种功能性成分,具有广谱抗菌、抗病毒感染作用,同时还能促进人体对铁的吸收。因此,将乳铁蛋白添加到巴氏奶中,不仅可以增强其抗菌能力,延长保质期,同时还能够提高产品的营养价值。在不同温度下(恒温37℃、常温23℃、冷藏4℃),在巴氏奶中添加不同浓度(0.025、0.05、0.1mg/ml)的乳铁蛋白,通过对巴氏奶添加乳铁蛋白和不添加乳铁蛋白在不同温度贮存时微生物的变化的比较,观察其微生物生长变化情况;结果表明,添加乳铁蛋白具有延长巴氏消毒奶保藏期的作用。 相似文献
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牛乳铁蛋白抗菌活性及其影响因素的研究 总被引:1,自引:0,他引:1
乳铁蛋白具有广谱的抗菌性 ,它通过直接性的“铁剥夺”和间接性的“膜渗透”2种机制发挥抗菌作用。文中开展了牛乳铁蛋白抗菌活性的研究 ,研究表明 ,牛乳铁蛋白对大肠杆菌的最小抑菌浓度为 2mg/mL ,对金黄色葡萄球菌的最小抑菌浓度为 1 6mg/mL。葡萄糖、蔗糖、麦芽糖、牛血清白蛋白 (BSA)、尿素、硫酸铵在 0~ 1 0mg/mL ,乳糖、可溶性淀粉在 0~ 4mg/mL ,酪蛋白在 0~ 1 2mg/mL的质量浓度范围内 ,对牛乳铁蛋白的抗菌活性影响不大。当NaCl或KCl的浓度为2 5~ 1 0 0mmol/L ,MgCl2 或CaCl2 的浓度为 1 0~ 5 0mmol/L时 ,牛乳铁蛋白的抗菌活性就会大大降低。随着缓冲盐浓度和有机酸浓度 (2 5~ 1 0 0mmol/L)的增大 ,牛乳铁蛋白的抗菌活性呈下降趋势 ,且在微碱性pH环境下牛乳铁蛋白表现出较强的抗菌活力。 相似文献
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Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates 总被引:2,自引:0,他引:2
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. 相似文献
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Anne Theobald Catherine Simoneau Philippe Hannaert Patrizia Roncari Anna Roncari Thomas Rudolph Elke Anklam 《Food Additives & Contaminants》2000,17(10):881-887
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. 相似文献
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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. 相似文献
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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. 相似文献
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A. Boenke 《Food Additives & Contaminants》2001,18(12):1135-1140
The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here. 相似文献
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《肉类研究》2014,(12)
<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 相似文献
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《印刷工业》2014,(9):94-95
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; 相似文献
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The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)" 下载免费PDF全文
《造纸信息》2014,(8)
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 相似文献
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《纺织机械》2014,(3)
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, 相似文献
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《造纸信息》2014,(8):99-100
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. 相似文献