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1.
采用L9(34)正交实验方法、考察提取法与水浴提取法中乙醇浓度(A),作用时间(B),温度/功率(c),料液比(D)4个因素对总黄酮提取量的影响,筛选最佳提取工艺;以此优化工艺分析不同种类及浓度的激素对再生苗总黄酮含量的影响,分析提取物的不同菌体的抑制效果.结果表明超声波提取法优于水浴法,最佳参数固液比为110,在80%的乙醇中按50%的功率处理30min;源于添加0.5 mg.L-1Kt的MS培养基再生的扯根菜中的总黄酮含量最大,为3.28%;提取物对金黄色葡萄球菌具有最大的抑制效果.添加激素的提取物对金黄色葡萄球菌和铜绿假单胞菌的抑菌效果具有促进作用.  相似文献   

2.
研究比较了超声波法、微波法、乙醇提取法等工艺提取黄芪总黄酮的效果,得出超声波法提取黄芪总黄酮的工艺最佳.以提取温度、提取时间、料液比、乙醇体积分数为考察因素,黄芪总黄酮提取率为考察指标,采用止交试验法优化黄良总黄酮提取工艺.结果表明,最佳工艺条件为:超声波提取温度为65C、提取时间30min、料液比为1:15(g/mL)、乙醇体积分数为65%,总黄酮的提取率为0.418%,是微波提取法的1.31倍,乙醇提取的1.69倍.  相似文献   

3.
白子菜总黄酮含量的测定   总被引:3,自引:0,他引:3  
白子菜样品经45%乙醇提取后,以芦丁为标准品,用聚酰胺吸附-硝酸铝显色法于510nm处测定总黄酮含量.结果表明,白子菜植株总黄酮质量分数为1.43%,叶为1.16%,茎为2.60%,根为4.28%.研究结果可为利用白子菜生产黄酮类药用成分提供科学依据.  相似文献   

4.
超声波提取抱茎苦荬菜总黄酮工艺的研究   总被引:1,自引:0,他引:1  
以抱茎苦荬菜全草为原料,在单因素实验基础上,以乙醇浓度、超声时间、超声功率、料液比4因素进行正交实验,优化超声波提取抱茎苦荬菜内总黄酮物质的提取工艺.在实验影响因素中,影响程度从大到小依次为超声波功率>乙醇浓度>料液比>超声提取时间.实验结果表明,抱茎苦荬菜全草中黄酮类物质的最佳提取条件为:7.72 mol/L乙醇,料液比1:20,超声功率400 W,在50℃提取60 min,连续提取2次,总黄酮得率高达1.102%.  相似文献   

5.
为了优选光石韦叶中总黄酮类化合物的超声波提取工艺,以芦丁为对照品,乙醇浓度、料液比、超声时间、萃取温度为影响因素设计正交实验,采用紫外分光光度法测定总黄酮得率。最终确定光石韦叶片总黄酮超声波提取最佳工艺为:乙醇浓度50%,料液比1∶40,时间40min,温度70℃。在此工艺条件下,超声波提取总黄酮平均得率为16.16%,由此可见,超声波辅助提取法可以加快提取速度,提高提取效率。  相似文献   

6.
采用超声波辅助法来提取紫苏叶总黄酮,通过研究提取剂乙醇浓度、料液比、超声波处理时间、浸提水浴温度等单因素及正交试验对紫苏叶总黄酮提取率的影响,确定了超声波辅助提取紫苏叶中总黄酮的工艺条件.结果表明,在浸提液为30%的乙醇、料液比1∶40、超声波(80 Hz、200 W)处理70 min、80 ℃水浴温度下提取2次,得到的紫苏叶粗提液总黄酮含量最高,提取率为21.81 mg/g.  相似文献   

7.
葛根总黄酮成分的超声提取及抗氧化作用   总被引:19,自引:0,他引:19  
采用超声波方法从葛根中提取总黄酮,用正交法确定了超声波方法提取总黄酮的最佳工艺条件为:乙醇浓度70%,超声波提取25min,提取次数3次,温度25℃;同时测定了在最佳条件下提取的葛根总黄酮对DDPH自由基的清除率,证实葛根总黄酮具有一定的抗氧化作用,是一种天然的抗氧化剂。  相似文献   

8.
以显脉旋覆花根为试验材料,用乙醇和甲醇为提取剂,采用浸提法分别对显脉旋覆花根中总黄酮进行提取,并用紫外分光光度法进行了测定.结果表明:乙醇70%,甲醇体积分数50%,浸提时间均为24 h时,总黄酮的提取效果较好,乙醇和甲醇提取的总黄酮得率分别为2.33%和1.84%,乙醇的提取效果优于甲醇,总黄酮测定方法平均回收率为99.89%,相对标准偏差RSD为0.89%,结果可靠.  相似文献   

9.
目的研究马鞭草总黄酮的超声波辅助提取方法。方法通过单因素试验和正交试验,探讨影响超声波辅助提取马鞭草总黄酮的优化工艺条件,并对马鞭草中黄酮类化合物的抗氧化活进行测定。结果马鞭草中总黄酮的最佳超声提取工艺条件为乙醇溶液体积分数70%、固液比1:40(g/mL)、超声功率500W、超声辅助提取温度70℃条件下提取20min,在此条件下提取率可达2.87%。影响马鞭草中总黄酮提取效果的主次因素为:固液比〉超声波功率〉提取温度〉乙醇体积分数。马鞭草黄酮类化合物具有清除羟自由基、超氧阴离子自由基的作用,其清除效果在一定范围内随着黄酮类化合物质量浓度的增加而增强。结论运用超声波辅助提取法从马鞭草中提取黄酮类化合物可以加快提取速度,提高提取效率,方法简单,结果准确,重现性好,是提取马鞭草总黄酮的有效途径。  相似文献   

10.
超声波强化提取牡丹花黄酮   总被引:8,自引:0,他引:8  
采用超声波技术对牡丹花黄酮提取进行强化,选择超声频率、乙醇浓度、超声时间、物料比为因素进行正交实验,优选出超声提取最佳工艺:即以70%的乙醇,料液比为1:20,在频率为22kHz的超声波下处理10min,提取率可达91.5%。具有提取效率高,提取时间短,温度低的优点。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

18.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
赵英华 《科技信息》2008,(12):219-220
0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation's behavior in their social life throughout the long history is beyond list.  相似文献   

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