共查询到19条相似文献,搜索用时 62 毫秒
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金樱子粗多糖的脱蛋白研究 总被引:3,自引:0,他引:3
采用Sevag法、酶法、酶法与Sevag法相结合对金樱子多糖进行脱蛋白研究。结果表明,酶法与Sevag法结合脱蛋白效果最佳,具体操作条件为酶用量为底物浓度的1%、pH为6.0时、60℃水浴3h,再加入占总体积1/5的氯仿-正丁醇(5∶1)溶液进行脱蛋白,重复操作5次,此时蛋白脱除率为80.5%,多糖含量为84.3%。 相似文献
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大枣多糖脱蛋白的研究 总被引:3,自引:0,他引:3
讨论采用大枣多糖酶制剂法脱蛋白的最佳工艺条件,试验确定为:温度60℃,pH5.0,浓度10g/L木瓜蛋白酶酶液与多糖液的体积比为0.4:1,酶解时间90 min,蛋白除去率为91.8%. 相似文献
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以蛋白去除率和多糖损失率为指标,比较Sevag法、三氯乙酸(trichloroacetic acid,TCA)法、木瓜蛋白酶法、木瓜蛋白酶-Sevag联用法和木瓜蛋白酶-TCA联用法脱除蚕蛹多糖蛋白的效果。结果显示:木瓜蛋白酶-TCA联用效果最好,其脱蛋白的最佳条件为木瓜蛋白酶用量[E]/[S] 2.0%、酶解温度50℃、酶解反应1.5h、采用TCA法除蛋白1次,此时蛋白去除率为97.98%,多糖损失率为18.76%;紫外光谱扫描定性实验显示脱蛋白的多糖在260~280nm处只有少量吸收,表明大多数蛋白已去除。木瓜蛋白酶-TCA联用法是一种有效的多糖脱蛋白方法。 相似文献
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Antioxidant activities of crude tea polyphenols, polysaccharides and proteins of selenium-enriched tea and regular green tea 总被引:1,自引:0,他引:1
Fang Yu Jianchun Sheng Juan Xu Xinxin An Qiuhui Hu 《European Food Research and Technology》2007,225(5-6):843-848
The crude tea polyphenols, polysaccharides and proteins of regular green tea and Se-enriched green tea were investigated in
vitro for antioxidant activities by auto-oxidation test (AAPH) and α,α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging
method. Results showed that crude tea polyphenols of Se-enriched green tea provided the highest antioxidant activity by DPPH
assay and the antioxidant activity was decreased in the order: crude tea polyphenols > crude tea proteins > tea polysaccharides.
The crude protein of Se-enriched green tea was found to exhibit the highest antioxidant activity by AAPH method and the antioxidant
activity was decreased in the order: crude tea proteins > tea polyphenols > tea polysaccharides. Tea polyphenols and tea polysaccharides
of Se-enriched green tea presented significantly higher antioxidant activities than that of regular green tea. No significant
difference of antioxidant activities was found between crude tea proteins of Se-enriched green tea and regular green tea.
The combinations of Se with tea polyphenols and tea polysaccharides were responsible for the higher antioxidant activities
of Se-enriched green tea than regular green tea. 相似文献
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Dongfeng Wang Xiaoling Zhou Lei Li Yangfeng Hou Jipeng Sun Jingfeng Wang 《European Food Research and Technology》2008,226(4):691-696
Tea polysaccharides (TPS) from five different kinds of tea contain similar composition of sugars and amino acids. Polysaccharide
part of TPS is mainly composed of arabinose, galactose and glucose with the approximate molar ratio of 1:1:0.5. Protein part
of TPS is composed of 16 normal amino acids among which Val, Ala, Gly, Glu are the major proportion. Based on the results,
the purified TPS was used as the calibration standard in phenol sulfuric acid reaction for the calibration curve that was
constructed by plotting absorbance versus mass of TPS with a correlation coefficient of 0.9961. In the developed method, TPS
mass recovery ranges from 84.88 to 95.7% with a relative standard deviation of 5.53%. It is found that the developed method
is simple, rapid, reliable and is ideally suitable for quantifying TPS from green tea or oolong tea. 相似文献
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探讨乙酰化修饰对绿茶多糖清除自由基、NO-2活性的影响,设计正交实验研究乙酰化修饰的最佳反应条件,在此条件下制取乙酰化绿茶多糖,对其修饰前后超氧阴离子(O-2·)自由基、羟自由基(·OH)和NO-2体外清除活性进行比较,并进行不同取代度的乙酰化茶多糖进行自由基及NO-2的清除作用实验,考察清除活性与取代度之间的关系。实验所得到乙酰化修饰最优条件为:茶多糖质量(g)与乙酸酐体积(m L)比为1∶40,保温时间4h,反应温度为30℃,乙酰化绿茶多糖最大取代度为0.337,乙酰化绿茶多糖对O-2·、·OH和NO-2体外清除活性最大提高率分别为32.06%、36.96%,55.99%,随着取代度的增大,O-2·、·OH及NO-2的清除活性均增大。研究证明乙酰化修饰能够提高绿茶多糖自由基、NO-2清除活性,且取代度与清除活性有关。 相似文献
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探讨了热水浸提提取柏树菌粗多糖的实验流程及条件.经热水提取,Sevage法去除蛋白质,乙醇沉淀等处理,得到多糖.从不同方面对柏树菌多糖的分离、纯化条件进行优化研究.通过单因子实验和正交实验进一步优化提取实验条件,在此条件下可得粗多糖5%左右. 相似文献
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为探讨黑茶茶褐素与茶多糖对脂肪酶的抑制作用,选择不同地区相同级别的黑茶为原料,提取茶褐素与茶多糖,采用对硝基苯酚法,分析茶褐素与茶多糖对脂肪酶活性的抑制率,并探讨各黑茶茶褐素与茶多糖对脂肪酶的抑制机理。结果表明:黑茶茶褐素与茶多糖对脂肪酶具有显著的抑制作用,普洱茶茶褐素与茶多糖IC50最小,分别为25.96,47.57mg/mL,抑制效果最好;其次为六堡茶;抑制效果最差的为茯砖茶褐素与茶多糖;康砖茶褐素与茶多糖抑制效果介于六堡茶与茯砖茶之间。各黑茶茶褐素的抑制类型均为可逆竞争性与非竞争性混合型,其中六堡茶接近于竞争性抑制类型;普洱茶、六堡茶与康砖茶多糖的抑制类型为可逆竞争性与非竞争性混合型,茯砖茶多糖抑制类型为可逆竞争性抑制。 相似文献
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研究绿茶在50、60、70、80℃水中不同时段萃取时萃出液中茶多酚(EG、EGC、ECG、GGEG)、氨基酸、果胶等的变化。结果显示,游离型儿茶素在冷水中比较容易溶出,3萃时有80%~90%溶出;酯型儿茶素的溶出较慢,3萃时只有50%左右溶出;咖啡因的溶出特性与游离型儿茶素相类似;氨基酸在1萃溶出量较多,从1萃到3萃前,依次下降,除精氨酸外,其他氨基酸在2萃时溶出率达70%~80%,3萃时溶出率为90%~100%,精氨酸在2萃时溶出率为50%,3萃溶出率为70%;钙、镁、磷酸类在1~3萃取中溶出量依次降低;1萃时水溶及盐溶性果胶的萃取率较高。以上参数为茶饮料的工业化生产及品质保证提供参考。 相似文献
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茶树花水提多糖的精制工艺初探 总被引:8,自引:0,他引:8
目的:优化茶树花多糖(Tea Flower Polysaccharides,TFPS)的提取、脱色、脱蛋白工艺,精制TF-PS。方法:先以TFPS的提取率为指标,正交实验法对TFPS水提过程中的提取温度(A)、提取次数(B)、提取时间(C)及料水比(D)4因素进行优选研究;再分别对TFPS不同脱色、脱蛋白方法效果进行对比;最后UV检测和凝胶层析鉴定纯度。结果:影响TFPS提取率的主要因素是温度和时间;TFPS的最佳提取参数为:温度为95℃、料水比为1∶10、次数为3次、时间为3h;筛选得出树脂法脱色效果最好,酶法-Sevage联用法脱蛋白效果最好,最佳提取、脱色、脱蛋白工艺处理获得的TFPSⅠ,280nm处有紫外吸收峰,Sephadex G-150洗脱曲线为单一对称峰。结论:TFPS是糖蛋白复合体,TFPSⅠ具有高度均一性。 相似文献