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1.
研究了乳蛋白经恒磁场处理后的体外酶消化作用,结果表明:磁处理可提高胰蛋白酶对热变性牛乳蛋白,酪蛋白(CSN)的消化率;提高牛乳中蛋白酶对变性CSN的消化率;降低瘤胃胞外蛋白酶对变性CSN的消化率。磁处理对胰蛋白酶分解奶粉蛋白、牛血清白蛋白影响不显著,并且不影响牛血清白蛋白及热变性CSN的紫外吸收光谱。  相似文献   

2.
对水解黄粉虫蛋白适宜的酶进行了研究,结果表明:胰蛋白酶水解黄粉虫蛋白是最佳选择。并对影响酶解反应的因素进行了选择和分析,适宜的反应条件为:黄粉虫与水的重量比为30∶105,酶作用量为黄粉虫重量的0.5%,控制反应温度50℃,酶解时间5h,pH=8.0。在此基础上,针对单一酶水解的特异性,蛋白质水解率低的问题,进行了提高其水解率的研究,结果发现,采用脱脂、浸提、双酶水解等处理可大大提高蛋白水解率。最后用发酵法脱除异味,制得一种氨基酸含量丰富的水解液  相似文献   

3.
通过研究鲍鱼水解肽的清除自由基能力、还原能力来评价其抗氧化活性,测定水解肽的相对分子质量分布情况、氨基酸含量,对鲍鱼水解肽的营养价值进行全面分析. 结果表明:鲍鱼水解肽具有较强清除自由基的能力和还原力;其相对分子质量在107~10031u范围内呈连续分布,其中小于5000u的水解肽占比达82.0%;水解肽由18种氨基酸组成. 当温度在20~60℃,pH值为7、8、10时水解肽的活性无显著变化,金属离子对DPPH自由基的影响随质量浓度增加逐渐增强,经胃蛋白酶和胰蛋白酶消化5h后,DPPH自由基清除能力保持率分别为(66.03±0.29)%、(109.03±0.57)%.  相似文献   

4.
采用缓冲液提取、盐析、凝胶过滤及离子交换层析等方法,从苦荞种子中分离纯化出1种类胰蛋白酶水解酶,经十二烷基硫酸钠一聚丙烯酰胺凝胶电泳(SDS—PAGE)测得其分于量为67kD,等电聚焦(IEF)测得等电点为6.3.该酶可以水解胰蛋白酶的底物BApNA,而且其活性不受苦荞胰蛋白酶抑制剂的影响.通过比较,苦荞中的胰蛋白酶水解酶在性质上与报道的甜荞BAPAase极为相似,可能属于同一类蛋白酶.  相似文献   

5.
鲨软骨粘多糖的酶法提取及组分分析   总被引:2,自引:1,他引:1  
通过正交实验法分别研究单酶法提取次数和双酶法不同提取方式对鲨软骨粘多糖提取率的影响,从而获得胰蛋白酶和/或木瓜蛋白酶水解鲨软骨提取粘多糖的最佳工艺:并采用乙酸纤维素薄膜电泳和琼脂糖凝胶电泳分析不同提取方法获得的粘多糖的组分.实验结果表明:双酶水解方式比单酶水解方式的软骨降解率和多糖提取率要高;在双酶水解方式中,木-胰方式比胰-木方式能更有效地降解软骨,并且能获得更高的粘多糖提取率;而木瓜蛋白酶法提取的粘多糖纯度比胰蛋白酶法高.  相似文献   

6.
:37℃下用胰蛋白酶水解SOD ,于 2 ,4,6 ,8和 1 0h对水解样及对照进行聚丙烯酰胺凝胶电泳 ,同时用邻苯三酚自氧化法测定酶活。结果表明 ,在体外SOD不能被胰蛋白酶水解 ,不同时间处理的SOD PAGE电泳谱带与对照完全一致。即活性染色均出现 4条带 ,蛋白染色均出现 6条带。 4条谱带于酶活性染色图谱中表明有酶活力 ,而另 2条无活力。胰蛋白酶水解处理后SOD活力呈明显下降趋势 ,水解 1 0h酶活降至原来的 80 %左右。与对照 37℃温度处理SOD活力下降趋势相同 ,推测可能是温度使酶变性对活力下降起主要作用。  相似文献   

7.
胰蛋白酶是一种水溶性的大分子酶蛋白,它可以消化水解蛋白质多肽链上的赖氨酸和精氨酸羧基,藉以研究蛋白质的结构和功能的关系。近年来,国内外一些学者已将胰蛋白酶作为研究光合膜结构功能的一种手段,不过目前对胰蛋白酶在光合作用电子传递链上光系统Ⅱ中作用的部位还存在着不同的看法。我们利用胰蛋白酶消化叶绿体,比较研究了消化叶绿体对  相似文献   

8.
污泥超声预处理促进厌氧消化反应试验   总被引:4,自引:0,他引:4  
利用低频超声技术,对污水厂剩余污泥进行破解处理,研究破解反应对提高厌氧消化反应速率和效率的影响,试验结果表明,与未预处理污泥相比,超声破解能够明显提高污泥厌氧消化的生物气产量和有机物去除率,缩短厌氧消化时间.在5—15min的超声破解时间范围内,破解时间越长,厌氧消化效率提高越大,污泥经超声波预处理后,在生物气产量和有机物去除率维持稳定的条件下,厌氧消化时间可由一般20d缩短到8d.并且发现,经破解的污泥,当厌氧消化时间缩短时,单位污泥的产气率反而呈增加趋势.  相似文献   

9.
胆碱对黄鳝消化酶活性的影响   总被引:1,自引:0,他引:1  
研究了饲料中添加不同胆碱量对黄鳝消化系统内4种消化酶—蛋白酶、胰蛋白酶、淀粉酶和脂肪酶活性的影响.结果表明:黄鳝摄食不同胆碱量的饲料,其肝脏、胃和肠道等消化器官的蛋白质酶、胰蛋白酶、淀粉酶和脂肪酶的活性均存在变化,随着胆碱量的增加,此4种消化酶的活性均呈上升的趋势,且当添加量达到0.8%以上时,其活性增加显著.饲料中添加适宜的胆碱可提高黄鳝对饲料的消化能力.  相似文献   

10.
猪胰蛋白酶经胃蛋白酶有限度地水解后的活性产物可以用大豆胰蛋白酶抑制剂STI-Sepharose亲和层析方法分离出三种形式的活性分子:K~(**) ,λ~(**)和μ~(**)胰蛋白酶。三者的分子量与母体酶分子β-胰蛋白酶的分子量相同。它们与特异性底物反应时,三者的活性各异。N末端基测定,表明三者N末端氨基酸的不均一性。结果说明,猪胰蛋白酶经胃蛋白酶水解后在一至两个肽键处发生断裂,由于分子内二硫键的连接,并未导致胰蛋白酶肽链的脱落。  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.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
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   

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