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目的:确定黄粉虫抗菌肽的最佳酶解工艺。方法:以黄粉虫为原料,碱提酸沉法提取黄粉虫蛋白质,再利用筛选出的蛋白酶进行水解,并用琼脂平板扩散法(打孔法)表征制得抗菌肽的抑菌活性。在单因素试验的基础上,应用Box-Behnken中心组合试验设计和响应面(RSM)分析法,探讨酶解温度、pH值、酶解时间、加酶量及底物质量浓度对酶解产物抑菌活性的影响。结果:碱性蛋白酶最适合水解黄粉虫蛋白制备抗菌肽,其最佳工艺条件为:底物质量浓度810g/100mL、酶解时间4.4h、加酶量440U/g pro、酶解温度54℃、pH9.5;酶解物抑菌圈大小理论预测值为15.17mm,实际测量值为15.04mm。结论:碱性蛋白酶水解黄粉虫蛋白能够得到抑菌活性较强的酶解物,优化的工艺条件与理论预测拟合程度较高。 相似文献
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为探究具有抑菌作用的核桃粕蛋白酶解抑菌肽的制备工艺,本实验以核桃仁经压榨提油后的副产物-核桃粕为原材料,利用酶解法制备核桃粕蛋白抑菌肽,优化制备工艺,进一步分离纯化,测试抑菌肽对金黄色葡萄球菌、大肠杆菌、枯草芽孢杆菌的抑制效果,筛选出具有最佳抑菌效果抑菌肽组分。研究结果表明:响应面优化胃蛋白酶酶解核桃粕工艺最佳条件为:温度54℃,pH3.46,加酶量5475.71 U/g,蛋白质水解度最优,可达13.99%;利用超滤技术对酶解肽分离纯化,得到4种不同分子量的酶解肽,抑菌实验表明H-Ⅱ (分子量为3~10 kDa)范围的酶解肽抑菌效果显著高于其他分子量范围的酶解肽(P<0.05)。本研究为核桃粕的深入研究利用以及新型抑菌肽产品的开发提供了数据支撑。 相似文献
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目的筛选得到产抗菌肽菌株,对抗菌肽进行分离纯化及理化性质研究。方法利用琼脂扩散法筛选产抗菌肽的菌株,运用细胞吸附解吸和阳离子交换层析法纯化抗菌肽,从热稳定性、酸碱稳定性和蛋白酶敏感性3方面研究抗菌肽的理化特性。结果筛选得到7株产抗菌肽的菌株,其中菌株4121具有较广的抑菌谱,命名为鼠李糖乳杆菌4121。对抑菌物质进行分离纯化和理化性质测定,电泳结果显示抗菌肽的分子量约为11 kDa,最终获得的抗菌肽比活力为12379.11 AU/mg,最终纯化倍数为91.99倍。该抗菌肽的抑菌能力在20~80℃及偏酸条件下具有很好的稳定性。同时该抗菌肽对蛋白酶K和α-胰凝乳蛋白酶敏感。结论筛选出的鼠李糖乳杆菌4121所产生的抗菌肽热稳定性及酸稳定性良好,具有广谱抑菌能力,并建立了有效的抗菌肽分离纯化法—细胞吸附解吸-阳离子交换层析法。 相似文献
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以牦牛血的胰蛋白酶水解液为原料,用Sephadex G-15凝胶柱,在以10 mmol/L磷酸盐缓冲液(pH7.0)为洗脱液,流速为0.4 mL/min的洗脱条件下,利用抗菌肽与细菌细胞膜的吸附结合特性,分离出两个含抗菌肽组分的洗脱峰。研究显示抑菌活性大的洗脱峰再经过RP-HPLC反复纯化,收集组分并检测抑菌活性,得到两个色谱纯的抗菌肽YakB-1和YakB-2。抑菌实验表明,抗菌肽YakB-1/2对细菌和真菌都具有广谱抗菌活性;抗菌肽YakB-2无论对G-菌还是G+菌的抗菌活性都比YakB-1强,但YakB-1对真菌的抑菌活性更强。研究结果可为牦牛血资源开发与利用提供参考依据。 相似文献
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响应面试验优化双酶酶解法制备鱼鳞抗菌肽工艺及其抑菌性能分析 总被引:2,自引:0,他引:2
采用双酶酶解法制备鱼鳞抗菌肽,进行酶筛选并通过响应面法优化酶解条件;通过葡聚糖凝胶G-25分离纯化酶解液,研究有效抑菌组分对不同菌的最小抑菌浓度(minimum inhibitory concentration,MIC)。结果表明,当采用碱性蛋白酶结合酸性蛋白酶分步酶解鱼鳞,底物质量浓度为30?g/100?mL时,最适酶解条件为碱性蛋白酶在pH?9.5时首次酶解,酶解时间62?min,酶解温度55?℃;酸性蛋白酶在pH?3.0时再次酶解,酶解时间3?h,酶解温度34.4?℃。此条件下制备的酶解液对副溶血性弧菌的抑菌圈直径为27.72?mm,与预测值基本相符。酶解液经层析后,其抑菌性G2组分对假单胞菌和希瓦氏菌的MIC为1.56?μg/mL,对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌、沙门菌及副溶血性弧菌的MIC为6.25?μg/mL。可见,双酶酶解法制备的鱼鳞抗菌肽具有较强的抑菌性。 相似文献
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以液压压榨澳洲坚果粕为原料,采用碱性蛋白酶水解制备澳洲坚果多肽(macadamia nut peptide-0,MNP-0),以对金黄色葡萄球菌与白色念珠菌的抑菌活性为跟踪指标,通过超滤、DA201-C型大孔吸附树脂、交联葡聚糖凝胶Sephadex G-25对其进行逐级分离纯化,获得抑菌活性较强的抗菌肽,并运用液相色谱串联质谱(liquid chromatography tandem mass spectrometry,LC-MS/MS)技术对其进行肽段组成与氨基酸序列分析。结果表明:超滤分离的不同分子量澳洲坚果多肽在所有多肽中所占质量分数不同,抑菌活性也有所差异。其中,澳洲坚果多肽组分MNP-4占比最高,为29.55%;抑菌活性也最强,对金黄色葡萄球菌与白色念珠菌的抑菌圈直径分别为10.01 mm与9.41 mm。大孔吸附树脂纯化多肽组分MNP-4的技术条件为75%乙醇溶液为解吸剂,静态吸附3 h,动态洗脱体积60 mL。经大孔吸附树脂与交联葡聚糖凝胶Sephadex G-25分离纯化,获得3个澳洲坚果纯化多肽(macadamia nut purified peptide,MPP)组... 相似文献
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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. 相似文献
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Sophie Guillot Laurence Peytavi Sylvie Bureau Renaud Boulanger Jean-Paul Lepoutre Jean Crouzet Sabine Schorr-Galindo 《Food chemistry》2006
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. 相似文献
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Jesus Simal-Gandara Miguel Sarria-Vidal Arjen Koorevaar Rinus Rijk 《Food Additives & Contaminants》2000,17(8):703-711
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. 相似文献
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M. S. Garcí a-Falc n J. Simal-G ndara S. T. Carril-Gonz lez-Barros 《Food Additives & Contaminants》2000,17(12):957-964
A simple, rapid and inexpensive method has been developed for the determination of benzo[a 相似文献
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H. J. Van Den Top A. Boenke P. A. Burdaspal J. Bustos H. P. Van Egmond T. Legarda A. Mesego A. Mourino W. E. Paulsch C. Salgado 《Food Additives & Contaminants》2001,18(9):810-824
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. 相似文献
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《肉类研究》2014,(2)
<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 相似文献
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《印刷工业》2014,(11):95-95
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%. 相似文献
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《印刷工业》2014,(8):103-103
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 相似文献
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《印刷工业》2014,(12):102-103
Sponsored by Printing and Printing Equipment Industries Association of China (PEIAC) and organized by Print China magazine, the Seventeenth Beijing International Printing Information Conference (INFOPRINT 2014) was successfully held on 11th Dec. 2014 at Dongguan Exhibition International Hotel. 相似文献