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1.
苦良姜又名黄姜。属于薯蓣科,薯蓣属。是理想的提取甾体激素类药物的重要原料,皂甙元(俗称皂素),其甾体结构化合物加以改造,就可得到各种不同的甾体激素类药物。从苦良姜根状茎中提取的最初产品为皂雄酮、醋酸孕酮(单酯)、强的松、可的松系列以及催产素、避孕  相似文献   

2.
基于清洁生产和资源综合利用的理念,提出一种从盾叶薯蓣根茎中提取薯蓣皂甙元的新工艺。该工艺由两部分组成,第一部分利用淀粉酶和糖化酶分离黄姜根茎中的淀粉,第二部分利用里氏木霉转化糖渣中的皂苷制备薯蓣皂甙元。研究表明,与直接酸水解相比,新工艺可以提取约98.7%薯蓣皂甙元,并以还原糖的形式回收98.0%淀粉,降低生产废水中99.4%COD,100%SO24-和100%酸。在酸水解废水中检测到24种有机物,其中邻苯二甲酸二丁酯和邻苯二甲酸-2-乙基己酯属于美国环保局优先控制污染物。而新工艺废水中仅检测到两种有机物(17β-羟基雄甾-5-烯-3-酮和邻苯二甲酸二异丁酯)。本研究为皂素清洁生产提供了一种新方法。  相似文献   

3.
黄姜皂甙元清洁生产工艺   总被引:2,自引:0,他引:2  
以黄姜为原料.研究提取皂甙元的清洁生产工艺。本工艺采用溶剂把黄姜中的皂甙与淀粉、纤维素等成分分离.然后再将皂甙水解、过滤、中和、脱水、提取、重结晶.从而得到高纯度的皂甙元。研究表明:用4样溶剂提取皂甙效果较好:溶剂的回收率可达98%以上:水解的酸浓度为[H^ ]=0.5mol/I较好、水解的压力为0.7—0.8Mpa较适合、水解时间为6h。在这些条件下.皂甙元的得率可以达到95%以上。本工艺产生的生产废水不到传统工艺的10%.酸的用量约为传统工艺的10%.皂甙元的得率有所提高.生产周期也大大缩短了.资源的综合利用率明显提高。  相似文献   

4.
甾体皂苷的选择性酸水解研究   总被引:1,自引:0,他引:1  
甾体皂苷的药物活性不仅与苷元有关,而且与糖链部分有更为密切的联系.为了研究糖链结构对甾体皂苷生物活性的影响,从龙葵(Solanum nigrum L.)和穿龙薯蓣(Dioscorea nipponica Makino)中提取了3种甾体皂苷类化合物澳洲茄边碱、澳洲茄碱和薯蓣皂苷,通过选择性酸水解,制备了一系列糖链结构不同的产物.研究结果表明,澳洲茄边碱水解得到4种产物,澳洲茄碱水解得到3种产物,β1-澳洲茄碱无法分离得到.用浓度为2%的H2SO4水解薯蓣皂苷,90℃反应75 min,主要得到γ-薯蓣皂苷水解产物,此条件下具有很好的选择性;而用5%的H2SO4水解,75℃反应75 min,则主要得到β-薯蓣皂苷水解产物.  相似文献   

5.
以月见草籽为原料,以乙醇-水做提取剂,采用溶剂浸取法提取月见草籽中的皂甙和甾体,通过化学法和光谱法对提取物进行定性分析,确定提取物为皂甙和甾体,同时研究了提取条件对提取率的影响.结果表明提取最佳条件是月见草籽和乙醇的质量比约为1∶8,乙醇体积分数95%,在回流温度下浸提8 h,该条件下的皂甙和甾体的提取率分别为0.405%和0.313%.  相似文献   

6.
硫酸浸泡法提取薯蓣皂苷元的研究   总被引:1,自引:0,他引:1  
鉴于传统工艺等方法的不足,介绍了从黄姜中提取薯蓣皂苷元新方法—硫酸浸泡法,并探索了硫酸浸泡黄姜提取薯蓣皂苷元的最佳工艺条件。以稀硫酸浸泡黄姜粉末数天,再加热酸解,采用单影响因素,对其工艺参数进行了探讨,得出最佳工艺条件:常温状态下用1.5 mol/L硫酸浸泡8 d,然后加热酸解2.5 h,提取率为1.258%,比传统工艺提高了15.9%。该方法操作简便、投资少、效果好。  相似文献   

7.
响应面法优化超声-酸水解法提取薯蓣皂素工艺研究   总被引:1,自引:0,他引:1  
采用先超声后水解的方法,从黄姜中提取薯蓣皂素.利用响应面分析法(response surface methodology,RSM)优化超声提取的工艺条件.实验结果表明,对于所研究的10 g黄姜,最佳提取乙醇体积分数为72%,溶剂体积为100 mL,超声时间为45 min,超声功率为420 W.与发酵-酸水解法提取薯蓣皂素相比,本方法提取率提高了26.46%.  相似文献   

8.
盾叶薯蓣中薯蓣皂甙元的提取研究进展(综述)   总被引:11,自引:0,他引:11  
简述了从盾叶薯蓣中提取薯蓣皂甙元的意义,对薯蓣皂甙元的化学结构、性质、提取和测定方法及应用领域进行了评述,概括了盾叶薯蓣中薯蓣皂甙元的提取与分离的研究现状.  相似文献   

9.
借助已有的酸水解/醇提取的方法,分析了来自四川攀枝花、成都、海南西部、南非中部4个不同生境地域的共10个蕃麻鲜叶片样品,以及来自云南楚雄元谋、保山施甸、丽江永胜、四川攀枝花4个典型的金沙江干热河谷地域的15个蕃麻麻膏(干料,含水量15~20%)样品,得到了其甾体总甙元组分、含量等基础数据资料。并在此基础上,重点开展了对蕃麻皂素的提取、分离、精制工作,建立了合适的工艺技术路线,乙酰蕃麻皂素产率4.7%。结果表明:金沙江干热河谷地域很适合蕃麻生长,而且生源积累优势组分蕃麻皂甙元,利于后加工,很有希望成为我国甾体药业新的原料基地。蕃麻作为一种种植业发展潜力巨大。  相似文献   

10.
黑叶菝葜中甾体皂甙成分研究   总被引:4,自引:0,他引:4  
从黑叶菝葜根中首次分得5个甾体甙和1个酚甙,采用化学方法和光谱技术鉴定其结构分别为:熊果甙(Ⅰ),胡萝卜甙(Ⅱ),薯蓣皂甙元-3-O-[α-L-鼠李吡喃糖基(1-4)]-β-D-葡萄吡喃糖甙(Ⅲ),薯蓣皂甙元-3-O-[α-L-鼠李吡喃糖基(1-2)]-β-D-葡萄吡喃糖甙(Ⅳ),薯蓣皂甙(Ⅴ)和孕甾-5,16-二烯-3β-醇-20-酮-3-O-[α-L-鼠李吡喃糖基(1-2)][α-L-鼠李吡喃  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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
1 Rise of studies on climate change's effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America's annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].  相似文献   

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