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1.
脱脂豆粕中提取大豆异黄酮的条件研究   总被引:4,自引:0,他引:4  
通过溶剂对比实验及单因素实验和正交实验,确定了从脱脂豆粕中提取大豆异黄酮的最佳提取溶剂及最佳提取条件.最佳提取条件为:乙醇浓度60%,提取温度70℃,物料比1:18,提取时间2h,提取次数2次.采用该方法从脱脂豆粕中提取大豆异黄酮的提取率为0.45%.  相似文献   

2.
以大豆豆粕为原料,以总异黄酮为目标产物。采用正交试验设计探讨了用乙醇—水体系作溶剂提取大豆异黄酮的最佳条件,即体积分数为70%的乙醇,m乙醇:V水=0.1g/ml。50℃下提取3次,每次回流时间1.0h。采用酸水解法和等电点沉淀法研究了异黄酮在提取液中的存在形式。即水不溶性异黄酮占8.0%,水溶性异黄酮占92.0%.其中与糖结合的占61.3%,与蛋白质结合的占30.7%。为进一步分离异黄酮提供了试验基础。采用HPLC法测定异黄酮的量。  相似文献   

3.
葛根提取物中异黄酮的测定   总被引:1,自引:0,他引:1  
用薄层层析法对陕西太白产野葛根提取物中的异黄酮进行了定性检测,确定了葛根素(Rf=0.21)、大豆甙(Rf=0.34)、大豆甙元(Rj=0.56)、芒柄 花素(Rf=0.76)的存在;在测定波长为249nm条件下,建立了测定葛根提取物中异黄酮含量的柱层析、紫外分光光地,线性回归方程A=0.046+92.55C(r=0.9998);平均回收率为99.1%(RSD=0.71)。  相似文献   

4.
大豆异黄酮提取及纯化分离工艺探索   总被引:6,自引:0,他引:6  
通过溶剂提取、浓缩、离心,然后进行层析分离,从大豆原料中提取及纯化分离大豆异黄酮,大豆异黄酮质量分数由原料中的0.0955%增加为提取液的0.582%,层析分离后达到8.23%,含量测定用HPCL法。  相似文献   

5.
均匀设计优化大豆异黄酮的超临界流体萃取   总被引:1,自引:0,他引:1  
采用CO2超临界流体法提取大豆中异黄酮类成分.在单因素实验的基础上,利用均匀设计法考察萃取压力、萃取时间、萃取温度及药材粒度等4因素对大豆异黄酮提取率的影响,确定了CO2超临界流体法提取大豆异黄酮的最佳工艺为萃取压力45 MPa、萃取温度50 ℃、萃取时间4 h、药材粒度40目,在此工艺条件下进行实验,大豆异黄酮的提取率为(0.361±0.012)%.  相似文献   

6.
为了提高黑豆中大豆异黄酮的提取率,采用超声提取法,以乙醇水溶液为提取溶剂,选择乙醇浓度、提取时间、提取温度及物料粉碎度进行四因素三水平的正交实验,考察各提取因素对黑豆中大豆异黄酮提取率的影响,以优选出黑豆中大豆异黄酮的最佳提取工艺.结果表明,物料粉碎后过20目筛,以60%乙醇水溶液为溶剂,温度为50℃,超声提取50 m...  相似文献   

7.
大豆天然甾醇的提取   总被引:6,自引:0,他引:6  
用皂化法研究了7种不同原料中大豆甾醇的提取量,实验表明大豆油脱臭馏出物(简称DD油))是大豆箱醇提取的理想原料,对皂化法从DD油中提取大豆甾醇的实验条件进行正交优化,最佳实验条件是:400gDD油,500mL乙醇(95%),50gKOH(82%),回流皂化2h.在此条件下.粗甾醇的产量为26.0g,纯度为47.5%.  相似文献   

8.
大豆异黄酮是大豆中的一类重要生理活性物质.近些年来,随着超声技术在异黄酮提取中的应用,其高效率、零污染的优点受到越来越多学者的关注.本文采用超声波结合乙醇法从酱油渣中提取大豆异黄酮,分别以乙醇浓度、料液比、提取时间、温度、提取次数、超声频率为单因素进行实验.结果表明,最佳的提取工艺条件是乙醇浓度为40%、料液比1∶50、温度30 °C、提取时间60 min、提取4次.  相似文献   

9.
大豆甙元磺酸盐对豚鼠离体回肠收缩的影响及途径分析   总被引:2,自引:0,他引:2  
实验采用豚鼠回肠离体肠段,置于装有Krebs液的恒温灌流浴槽中,记录肠段收缩活动,探讨大豆甙元对消化道平滑肌的作用及其作用机理.结果表明,大豆甙元磺酸盐对豚鼠离体回肠收缩有明显抑制作用,纳洛酮能减弱大豆甙元磺酸盐对回肠的抑制作用,心得安、酚妥拉明、阿托品均不影响大豆甙元磺酸盐对回肠平滑肌的作用.实验结果提示,大豆甙元能抑制回肠平滑肌的收缩活动,其作用部分由μ-受体介导.  相似文献   

10.
超声波辅助提取大豆异黄酮生产工艺条件优化   总被引:2,自引:0,他引:2  
探讨用超声波法提取大豆中异黄酮的工艺,大豆粉过40目筛,以石油醚脱脂后通过单因素实验和正交试验改变不同的提取工艺选取最佳提取条件。结果表明超声波辅助提取大豆异黄酮是行之有效的方法,影响提取的主次因素为乙醇浓度>料液比>温度>时间。最佳提取条件为:提取时间40 min,料液比1∶30(g.mL-1),乙醇体积分数60%,温度70℃。  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.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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