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1.
紫外光谱分析法对辣椒素萃取工艺的研究   总被引:2,自引:0,他引:2  
以辣椒素稀溶液为原料,利用紫外光谱法对辣椒素萃取工艺进行了研究,获得了较理想的萃取工艺条件。  相似文献   

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超临界CO2萃取烟叶中茄尼醇的工艺研究   总被引:1,自引:0,他引:1  
采用超临界二氧化碳萃取烟叶中的茄尼醇,考察了萃取过程温度、压力、二氧化碳流量、萃取方式、夹带剂种类及其用量对萃取过程的影响。采用四因素三水平的正交设计,以茄尼醇的提取率为指标,对萃取条件进行了优化。并建立了能较准确测定烟叶中游离茄尼醇含量的方法,采用高效液相色谱对萃取产物进行了分析。以探索提高提取率的方法,为其工业化生产提供参考。结果表明:最佳萃取工艺条件为:甲醇为夹带剂,萃取温度45℃,萃取压力25MPa,CO2流量15kg·h-1。在最佳工艺条件下茄尼醇的提取率为:92.1%。  相似文献   

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本文探索AOT-异辛烷反胶束萃取苦参碱的最佳工艺和条件,以AOT-异辛烷反胶束对粗苦参碱中的苦参碱进行萃取,利用毛细管电泳对苦参碱进行定量分析,通过正交试验优化萃取工艺和条件,确定影响萃取率的主要因素为萃取水相的酸度,次要因素为水相的温度,反胶束的W0和离子强度对萃取率的影响较小,得出最优萃取条件为:pH=12,W0=30,T=35℃。  相似文献   

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目的:为明确薯蓣皂苷元的最佳提取工艺,我们采用超临界CO2萃取技术,通过正交试验优化穿山龙中薯蓣皂苷元的提取工艺。方法:探讨萃取压力、萃取温度、分离Ⅰ压力、分离Ⅰ温度等因素对薯蓣皂苷元收率的影响。确定了薯蓣皂苷元的最佳萃取条件。结果:穿山龙中薯蓣皂苷元超临界萃取的最佳条件为萃取压力30 MPa,萃取温度50℃,分离Ⅰ压力13 MPa,分离Ⅰ温度40℃。结论:超临界CO2萃取法提取薯蓣皂苷元工艺简单,安全有效。  相似文献   

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本实验以永州香樟叶为原料,优化了超临界CO2萃取制备香樟叶精油的工艺条件。结果显示,超临界CO_2萃取香樟叶精油的最适工艺条件为:CO_2流量20 L/h,萃取压力18 MPa,萃取温度46℃,萃取时间1.6 h,在此工艺条件下永州香樟叶精油萃取率可达到98.37%,高出索氏提取法42.97%,高出水蒸气蒸馏法26.69%。当加入0.6%CO_2流量的乙醇作为夹带剂萃取时间缩短了26 min,可进一步节省能耗。同时研究了永州香樟叶精油在一年内各季度的变化规律,发现夏秋两季精油含量水平较高,而春冬两季较少,在1月含量达到最低。  相似文献   

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超临界CO_2和微波辅助萃取艾叶挥发油工艺的研究   总被引:13,自引:0,他引:13  
曾虹燕  张晓云  冯波 《广西植物》2005,25(3):285-288,263
通过超临界CO2萃取均匀设计实验和微波辅助萃取艾叶挥发油的正交实验比较,考察影响提取的主要因素,寻求最佳萃取工艺。超临界CO2萃取最佳工艺条件为:萃取压力16MP,萃取温度31℃,CO2流量20kg/h和时间80min,得率3.75%;微波萃取最佳工艺条件为:辐射功率720w,辐射时间200s,溶剂量400mL,洗涤剂量50mL,得率4.85%。水蒸馏法提取率为1.87%。结果表明超临界CO2和水蒸馏法萃取艾叶挥发油品质最好;微波萃取收率最高,但品质较差。  相似文献   

7.
响应面法对超临界CO_2萃取茶籽仁油的工艺优化   总被引:1,自引:0,他引:1  
为了保证茶籽油的原生态品质,研究了茶籽仁油的超临界CO2萃取技术,并运用响应面法对其萃取压力、温度和时间等工艺条件进行了优化分析,得到的最佳工艺条件是在33 MPa压力和43℃温度下连续萃取时间2 h。此条件下的萃取得率为39.6%、出油效率达86.5%,所得茶籽油只需简单的脱酸处理即达到国标GB11765—2003规定的压榨一级茶籽油水平。  相似文献   

8.
秋橄榄果实中番茄红素的超临界萃取技术研究   总被引:1,自引:0,他引:1  
秋橄榄果实中番茄红素含量丰富。利用超临界二氧化碳技术萃取秋橄榄中的番茄红素,对影响萃取的诸因素,如萃取压力、萃取温度、萃取时间、夹带剂等进行研究,并进一步用响应曲面法优化萃取工艺条件。结果表明:丙酮作为夹带剂效果最佳,优化后的最佳萃取工艺条件是萃取压力37MPa,萃取温度52℃,萃取时间3.8h。  相似文献   

9.
从废弃啤酒酵母细胞提取乙醇脱氢酶的新工艺   总被引:4,自引:0,他引:4  
用细胞破碎与两水相萃取相结合的新工艺从废弃的啤酒酵母细胞中提取乙醇脱氢酶,探讨了影响破碎萃取效率的因素,确定了破碎萃取的最佳工艺条件  相似文献   

10.
反向微胶团萃取分离酪氨酸的研究   总被引:4,自引:0,他引:4  
研究了AOT反向微胶团的性质 ,并以酪氨酸为反向微胶团的萃取对象 ,探讨了各种因素对酪氨酸分配比的影响 ,优化了萃取、反萃取的工艺条件。  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

16.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

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Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

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正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

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