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以当归多糖得率为指标,采用正交实验法对提取过程中水用量、提取时间、提取次数及醇沉浓度对多糖得率的影响进行研究。结果表明,最优提取工艺为8倍用水量,提取时间3 h,提取次数2次,醇沉浓度为60%。 相似文献
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以当归的多糖得率为评价指标,采用正交实验,运用紫外分光光度法对提取物中相关指标性成分的含量进行测定。结果表明,当归多糖最优提取工艺为12倍用量水,提取时间2 h,提取次数2次,醇沉浓度为70%。 相似文献
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以甘草和山药为主要原料,采用浸提法从中提取美白成分甘草酸及山药多糖,并对甘草提取物进行红外谱图表征,最终制备美白保湿霜。以保湿率为考察指标,分别探讨了在不同质量百分比下硬脂酸、十八醇、单硬脂酸甘油酯、甘草酸对美白保湿霜的影响,并经皮肤测试后证明美白保湿霜性能良好。 相似文献
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研究了热水法浸提牡丹雄蕊多糖的工艺。以热水为溶剂,考察了提取时间、提取温度、料液比,提取次数等因素对多糖提取率的影响。通过正交实验确定最佳提取工艺为:提取温度90℃,料液比1∶15(g∶mL),提取3次,每次提取3h,在此条件下,牡丹雄蕊多糖提取率为3.06%。 相似文献
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山药作为日常生活中一种常见的食材,口感细腻,营养丰富,具有增强人体免疫力、改善睡眠、补脾益肺等功效.现代医学研究表明,山药具有多种生物活性,并认为山药中的主要功效成分是山药多糖.本文对山药多糖的功效及其提取、纯化、含量测定方法研究予以综述. 相似文献
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Electrochemical detections of 14 munitions constituents (MCs) listed on the Environmental Protection Agency hazardous waste list were examined using square wave voltammetry. Of the MCs that showed peak resolution in the scanned range, the reduction potential, limit of detection and limit of quantitation are reported here. The MCs tested are in three groups: nitrobenzenes, nitrotoluenes, and other nitro-aromatics: tetryl, HMX, and RDX. There was a correlation between peak resolution and the number of nitro groups for the nitrobenzenes and nitrotoluenes. The nitro group distance from the methyl for the nitrotoluenes with two nitro groups showed some correlation to the ability to detect as well. Some mixture experiments were conducted in which MCs with three and two nitro groups were detected simultaneously. While tetryl readily displayed two peaks, RDX and HMX did not show such clear peak resolution. 相似文献
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Natural cellulose fibers with cellulose content, strength, and elongation higher than that of milkweed floss and between that of cotton and linen have been obtained from the stems of common milkweed plants. Although milkweed floss is a unique natural cellulose fiber with low density, the short length and low elongation make milkweed floss unsuitable as a textile fiber. The possibility of using the stems of milkweed plant as a source for natural cellulose fibers was explored in this research. Natural cellulose fibers extracted from milkweed stems have been characterized for their composition, structure, and properties. Fibers obtained from milkweed stems have about 75% cellulose, higher than the cellulose in milkweed floss but lower than that in cotton and linen. Milkweed stem fibers have low % crystallinity when compared with cotton and linen but the strength of the fibers is similar to cotton and elongation is higher than that of linen fibers. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers 相似文献
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茶叶活性成分综合提取过程研究 总被引:13,自引:0,他引:13
以低档绿茶为原料,研究了茶多酚、咖啡碱和茶多糖的提取、分离、纯化等工艺条件,探索出一条综合提取新工艺。研究表明,以纤维素酶和果胶酶为主体的复合酶解提取,可提高茶叶中各有效成分的提取率,并可降低其活性损失;通过超滤膜过滤酶提液不但精制了料液而且利用膜浓缩液可方便地制备茶多糖;采用H-600树脂吸附阶段洗脱层析法分离茶多酚咖啡碱,解决了传统工艺中使用有毒溶剂脱除咖啡碱的难题。文章计算了吸附柱的传质区高度和总传质系数,为放大设计奠定了基础。 相似文献
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采用超声波辅助提取法提取马齿苋中抑制糠秕马拉色菌的活性成分,通过纸片法测定其抑菌效果,并以抑菌效果为指标,采用单因素试验确定较佳提取工艺。结果表明,当提取温度为60℃,提取时间为50 min,料液比为1∶25(g∶mL),超声功率为210 W时,所得提取物的抑菌效果较佳,抑菌圈直径为(46.68±1.21)mm。通过理化反应对马齿苋提取物中的成分进行初步检识,结果表明马齿苋提取物中存在生物碱类、皂苷类、蛋白质多肽或氨基酸和糖类,可能含有鞣质及酚类、黄酮类和三萜类,不存在有机酸类。 相似文献
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超临界CO2萃取黑胡椒中有效成分的研究 总被引:2,自引:1,他引:1
用超临界CO2萃取技术,首先在低压、低温的条件下选择性萃取黑胡椒精油,进而在高温、高压及极性夹带剂的协同作用下,萃取富含胡椒碱的黑胡椒油树脂。另外,利用分子蒸馏技术纯化超临界CO2萃取的黑胡椒精油,得到适用于日化行业的无色、无辛辣感的挥发油,并通过GC-MS对比分析其香气成分。研究结果表明,超临界CO2萃取黑胡椒精油的较优条件为:萃取压力10MPa、萃取温度35℃、萃取时间1.5h,在该条件下产物得率为3.01%;超临界CO2萃取黑胡椒油树脂的最佳条件为:m(原料)∶m(体积分数95%食用乙醇)=2∶1、萃取压力30MPa、萃取温度50℃、萃取时间4h,在该条件下油树脂得率为7.88%,油树脂中胡椒碱质量分数为65.79%。 相似文献