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1.
干姜超临界CO2萃取与水蒸气蒸馏工艺比较研究   总被引:4,自引:0,他引:4  
目的:比较干姜的超临界CO2萃取与水蒸气蒸馏两种工艺的差别,为其在复方制剂中的应用提供工艺设计参考。方法:分别用超临界CO2萃取和水蒸气蒸馏处理干姜药材,采用GC、TLC对产物进行分析比较。结果:超临界CO2萃取产物得率为8.0%,水蒸气蒸馏得率为0.2%,GC、TLC显示超临界CO2萃取物比水蒸气蒸馏样品有较多的成分。结论:干姜的超临界CO2萃取工艺较水蒸汽蒸馏工艺的产物量高,成分较多。  相似文献   

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采用正交实验设计,对肾叶天胡荽(Hydrocotyle wigordi Maxim.)精油超临界CO2萃取条件进行了优化,并用GC—MS分析技术对精油的化学成分进行了鉴定,初步探讨了肾叶天胡荽精油对小菜蛾2龄幼虫的触杀活性。结果表明,肾叶天胡荽精油超临界CO2萃取的最佳条件为萃取压力35MPa、萃取温度50℃、解析压力5MPa、解析温度40℃、萃取时间75min、CO2流量34—36L·h^-1,精油得率最高可达5.32%。从精油中共鉴定出19种成分,总相对含量达到89.266%,主要成分为邻苯二甲酸二辛酯(64.302%)。用超临界CO2萃取技术提取的肾叶天胡荽精油对小菜蛾2龄幼虫有一定的触杀作用,20g·L^-1精油对小菜蛾2龄幼虫的24h校正死亡率高达90.00%。  相似文献   

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利用超临界CO2萃取微孔草籽油,并对籽油进行了HPLC/MS分析。实验确定的最佳超临界CO2流体萃取条件是:萃取温度45℃,萃取压力20MPa,CO2流量为35-40kg/h,萃取时间120min,在此条件下白刺籽油的萃取率为16.12%。利用HPLC/MS对微孔草籽油分析,发现其不饱和脂肪酸的相对含量高达73.19%。比较了超临界CO2萃取微孔草籽油油样和石油醚萃取微孔草籽油油样的理化性质,发现超临界CO2流体萃取的籽油质量优于传统溶剂萃取的籽油。  相似文献   

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超临界CO2萃取百合花挥发油的工艺研究   总被引:2,自引:0,他引:2  
本文介绍了超临界CO2萃取百合花中挥发油的提取分离工艺,重点研究了超临界CO2萃取压力、温度、时间对出油率的影响。正交试验结果表明:影响超临界CO2萃取的主要因素为C3〉A2〉B2(A为萃取压力,B为萃取温度,C为萃取时间);最佳工艺参数:SC-CO2萃取压力为18MPa,温度为50℃,时间为90min,流量为25L/min,所得百合花挥发油的出油率高达2.92%。  相似文献   

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超临界CO2萃取鱼腥草的挥发油成分   总被引:12,自引:2,他引:10  
从萃取的压力、温度、流量和时间等条件探讨超临界CO2萃取对鱼腥草(Houttuynia cordata Thunb.)挥发油萃取率的影响,确定最佳萃取条件为萃取压力20mPa、温度35℃、CO2流量40kg/h和萃取时间80min,鱼腥草挥发油得率为1.76%。而水蒸气蒸馏提取和石油醚提取的得率分别为0.05%和0.08%。超临界CO2法萃取的鱼腥草挥发油收率高,萃取时间短。  相似文献   

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本文通过超临界CO2提取芝麻油的均匀设计实验和微波和超声波诱导提取芝麻油的正交实验比较,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:压力32MPa,温度60℃,CO2流量31kg/h,萃取时问80min,得率46.39%;微波萃取最佳工艺条件为:溶剂为丙酮,物料与溶剂比例1:7,辐射时间7min,辐射功率810W,得率23.01%。超声波萃取最佳工艺条件为:物料与溶剂比例1:7,溶剂为石油醚,浸泡时间30h,得率23.99%。结果表明超临界CO2萃取芝麻油品质最好,而且萃取也最高,质量最稳定。  相似文献   

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通过对盆栽穿心莲(Andrographis paniculata)幼苗浇灌Cu SO4溶液实验,研究外施Cu2+对穿心莲幼苗的生理特性和药效成分含量的影响。结果显示,外施Cu2+对穿心莲幼苗的生长、生理生化指标和穿心莲内酯、脱水穿心莲内酯的含量均有显著影响。当Cu SO4溶液浓度超过6.25 mmol/L时,Cu2+能显著抑制穿心莲幼苗株高、叶长、叶宽的增长,且随胁迫时间的延长和Cu2+浓度的增大抑制作用增强;穿心莲叶片中超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量均随Cu2+浓度增大和胁迫时间的延长而升高,当Cu SO4溶液浓度达到12.5 mmol/L且胁迫20 d和30 d时,叶片中SOD活性达到对照组的168.3%和171.18%;过氧化物酶(POD)、过氧化氢酶(CAT)活性则随Cu2+浓度的增大呈先升高后下降的趋势;当外施Cu SO4溶液浓度大于1.25 mmol/L时,与对照相比,穿心莲药效成分穿心莲内酯和脱水穿心莲内酯的含量均显著降低(P0.05)。研究结果表明,外施Cu SO4溶液浓度高于6.25 mmol/L时,能显著影响穿心莲幼苗的生理特性和有效成分含量,从而降低穿心莲药材的产量和质量。  相似文献   

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研究棘托竹荪孢子粉超临界萃取物的抗氧化活性。采用超临界CO2萃取破壁棘托竹荪孢子粉,正交试验优化萃取温度、压力、CO2流速、萃取时间;气相色谱-质谱(gas chromatography-mass spectrometry,GC-MS)分析萃取物成分组成;通过检测萃取物清除DPPH自由基及ABTS+·能力考察其抗氧化活性。结果表明:萃取时间80 min、萃取温度45℃、萃取压力35 MPa、CO2流量25 L/h条件下,萃取得率达6.74%。GC-MS分析发现,从萃取物中共鉴定出40种成分,其中酸类物质13种、酯类10种、烃类7种、醇类4种、醛类3种、酮类2种、其他1种。其中相对含量最高的为芹子酸(23.23%),其次为亚油酸(19.98%)、二十烯(9.68%)、正十六酸(7.47%)及十九烯(7.12%)。萃取物具有较强的DPPH自由基和ABTS+·清除活性,其质量浓度10 mg/m L时,对DPPH自由基的清除率达86.41%,对ABTS+·清除能力为0.67 mmol Trolox/g。  相似文献   

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超临界CO2萃取大豆油与大豆磷脂工艺条件研究   总被引:10,自引:0,他引:10  
应用超临界CO2萃取技术从大豆中直接提取大豆油和纯度为95.98%的大豆磷脂。探讨了超临界CO2萃取的压力、温度、流量、时间等条件对大豆油和大豆磷脂的影响,确定其最佳萃取条件:萃取压力25MPa,温度50℃,CO2流量30kg/h,萃取时间150min,大豆磷脂夹带剂乙醇的流量为3kg/h,得率分别为15.72%和1.954%。  相似文献   

10.
艾叶超临界CO2萃取物的抑菌活性研究   总被引:9,自引:0,他引:9  
本文研究了艾叶超临界CO2萃取物的抑菌活性。结果表明:艾叶超临界CO2萃取物对细菌、酵母、霉菌都有一定的抑菌作用,在酸性环境和碱性环境较为显著,对大多数细菌、酵母、霉菌的MIC不超过0.78 g/L。高温长时间处理对萃取物抑菌活性影响较大,但高温瞬时或低温处理对萃取物抑菌活性影响不大。  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   

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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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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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