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1.
目的建立一种普洱茶中茶多糖的提取工艺。方法以普洱茶为材料,采用水提醇沉法,研究了浸提温度、浸提时间、浸提次数、乙醇浓度4个因素对普洱茶中茶多糖提取率的影响,并通过正交实验确定茶多糖的最佳提取工艺。且用此提取工艺测定市售不同级别普洱茶中茶多糖含量。结果普洱茶中茶多糖的最佳提取工艺为:浸提温度90℃,浸提时间40 min,浸提次数3次,乙醇浓度80%。该提取工艺重复性好,吸光度与葡萄糖含量呈良好的线性关系(n=5),线性范围0.02~0.10 mg/L(r2=0.9999)。实验也发现,普洱茶的嫩度越低,茶多糖的含量越高。结论本方法简便、快捷、重复性好,可作为茶叶多糖原材料和产品质量控制的方法。  相似文献   

2.
乌龙茶多糖提取工艺及抗氧化作用研究   总被引:2,自引:0,他引:2  
以乌龙茶为原料,研究不同因素对乌龙茶多糖得率的影响,初步探讨了乌龙茶多糖的抗氧化活性.结果表明,各因素对茶多糖得率的影响为:提取次数>提取温度>提取时间>料液比;最佳提取工艺为提取时间80min,提取温度80℃,提取次数3次,料液比1∶35.在此条件下,茶多糖得率为15.73%.体外抗氧化试验表明,乌龙茶多糖对羟自由基、超氧阴离子自由基、1,1-苯基-2-苦基肼自由基均具有一定的清除效果,且清除率随浓度的增大而增加.  相似文献   

3.
采用微波辅助提取油茶籽粕中的茶籽多糖。在单因素实验的基础上,利用正交实验优化茶籽多糖提取条件。并对茶籽多糖的体外抗氧化活性进行了研究。结果表明,茶籽多糖最佳提取工艺条件为:微波功率800 W,微波时间6.5 min,料液比1∶60,提取时间2 h,提取温度100℃。在最佳工艺条件下,茶籽多糖得率为(7.61±0.5)%。茶籽多糖对羟自由基、DPPH自由基和亚硝酸盐都呈现出一定的清除能力,但清除超氧阴离子自由基能力和还原能力较弱。  相似文献   

4.
绿茶中提取茶多糖最佳工艺的优化   总被引:5,自引:0,他引:5  
采用单因素实验和L9(34)正交实验对绿茶中茶多糖的提取工艺进行了研究,研究了料水质量比、浸提温度、浸提时间、浸提次数对茶多糖提取的影响。结果表明,影响茶多糖得率的主次因素为:料水质量比、浸提温度、浸提次数、浸提时间;最佳提取工艺条件为:料水质量比为1∶25,提取温度85℃,提取时间为90min,提取1次。在此最佳工艺条件下,茶多糖得率为1.92%。  相似文献   

5.
主要探讨辣木茎叶中水溶性多糖的提取工艺条件以及抗氧化活性。以辣木茎叶干粉为原料,采用水为提取剂,通过单因素和正交试验对浸提温度、浸提时间及料液比进行研究;采用水杨酸法和邻苯三酚法分别测定辣木多糖对羟自由基以及超氧阴离子的清除率,以确定提取物的抗氧化活性。实验条件下辣木茎叶多糖最佳提取工艺条件为料液比1∶20(g/mL)、浸提温度80℃、浸提时间120 min,在此条件下,辣木粗多糖的提取率可达5.66%;多糖提取物对羟自由基及超氧阴离子均有清除作用,且随着提取物浓度的提高对二者的清除作用逐渐增强,存在剂量效应关系。清除作用的半数抑制率(IC50)分别是7.252 8 mg/mL和2.501 1 mg/mL。  相似文献   

6.
为综合利用底圩茶资源,研究超声波辅助法提取底圩茶多糖工艺及体外抗氧化活性。考察颗粒度、超声时间、料液比、提取温度、超声功率5个因素对多糖得率的影响,通过正交试验确定其最佳提取工艺,并考察其抗氧化性。结果表明:最佳提取工艺为:颗粒度40目、料液比1:40 g/mL、超声时间110 min、提取温度60 ℃、超声功率750 W,在此条件下底圩茶多糖得率为11.28%±0.49%。抗氧化活性试验结果显示在浓度为2.0 mg/mL时,底圩茶多糖对O2-·、·OH、DPPH·、ABTS+·清除率分别为66.55%±2.67%、85.17%±1.70%、66.48%±2.99%、82.37%±1.00%,表明底圩茶多糖抗氧化能力较强,具有作为天然抗氧化剂的潜力。  相似文献   

7.
板栗多糖的提取及抗氧化活性研究   总被引:1,自引:0,他引:1  
通过正交试验对板栗多糖的最佳提取条件进行了研究;从还原能力,抗脂质体氧化及对Fenton体系产生的羟自由基和NO2-.自由基的清除效果等方面对板栗多糖的抗氧化活性进行了研究和评价。结果表明:最佳提取工艺为提取温度65℃、料液比1∶15(g/mL)、提取时间1.5 h,在最佳工艺条件下板栗多糖浸提两次后的提取率达到9.88%;板栗多糖具有一定的还原能力,对脂质体氧化,Fenton反应产生的羟自由基和NO2-.自由基均具有一定的消除作用或抑制作用,并随多糖浓度增加板栗多糖的抗氧化活性呈现出增强的趋势。  相似文献   

8.
芝麻叶多糖的提取及抗氧化活性研究   总被引:2,自引:0,他引:2  
目的:探讨芝麻叶水溶性多糖的提取条件及其抗氧化活性。方法:采用三因素三水平正交试验设计,研究提取温度、提取时间和料液比等因素对芝麻叶水溶性多糖提取率的影响,并对芝麻叶水溶性多糖清除O2-.、.OH、DPPH.自由基的能力进行研究。结果:芝麻叶水溶性多糖的提取条件是:料液比1∶10,提取温度75℃,提取时间45 min。抗氧化试验结果表明,芝麻叶水溶性多糖具有较好的抗氧化活性,其清除O2-.、.OH、DPPH.的IC50值分别为0.0250、0.2031、2.0510 mg/mL。芝麻叶水溶性多糖是一种效果好、安全性高的新型天然抗氧化物质,值得深入研究其生理功能并开发功能产品。结论:获得芝麻叶水溶性多糖的最佳提取条件,在该条件下芝麻叶多糖的得率为4.32%。芝麻叶水溶性多糖具有较明显的体外抗氧化能力。  相似文献   

9.
丁世环  张嘉杨  鲁群岷 《食品工业科技》2018,39(18):187-192,200
为了解决普洱茶茶渣所带来的环保问题,本研究探讨了普洱茶茶渣中茶多糖超声波提取的优化工艺,并研究了最佳提取工艺条件下的茶多糖的抗氧化性。在单因素实验基础上进行响应面试验,制定了茶多糖超声波辅助提取工艺的4因素3水平响应面法试验设计方案。研究结果表明,普洱茶茶渣中茶多糖超声波提取的最佳试验因素组合为:浸提温度为100 ℃、浸提时间为120 min、料液比为1:30 g/mL,超声波功率为420 W。在此条件下,茶多糖得率为2.29%。该工艺所得茶多糖对羟基自由基以及超氧离子自由基均具有较强的清除能力:当茶多糖浓度为3.2 mg/mL时,茶多糖对羟基自由基的清除率达到最高,为60.37%;当茶多糖浓度为2.4 mg/mL时,茶多糖对羟基自由基的清除率达到最高,为53.91%。  相似文献   

10.
目的:开发香菇柄多糖的工业化生产。方法:以多糖得率为指标,采用均匀设计试验优化提取工艺,采用4种方法测定多糖抗氧化活性并与传统的热水浸提法进行比较。结果:闪式辅助热水浸提法提取香菇柄多糖最优工艺条件为闪式提取时间120 s,液料比(V去离子水∶m香菇柄)40∶1 (mL/g),热水浸提时间105 min,温度50℃,提取两次,此条件下多糖得率为(5.03±0.22)%,与模型预测值基本一致,是传统热水浸提法的1.82倍;香菇柄多糖具有较强的Fe3+还原能力、总抗氧化能力、羟自由基和DPPH自由基清除能力,且呈量效关系;闪式辅助热水浸提法所得多糖抗氧化活性强于传统热水浸提法。结论:闪式辅助热水浸提有利于香菇柄多糖提取,且能保持其抗氧化活性。  相似文献   

11.
蛋白质水解度测定方法综述   总被引:27,自引:0,他引:27  
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。  相似文献   

12.
百年风尚     
《中国服装(北京)》2013,(19):130-133
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。  相似文献   

13.
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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。  相似文献   

18.
山药水溶性多糖的提取及抗氧化性研究   总被引:1,自引:0,他引:1  
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。  相似文献   

19.
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.  相似文献   

20.
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