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1.
基于响应面分析法的草鱼蛋白酶解工艺   总被引:7,自引:0,他引:7  
应用响应面分析法对草鱼蛋白两段酶解的条件分别进行优化,第一段酶解复合使用胰酶/风味蛋白酶(质量比为4:1),以蛋白质利用率为响应值;第二段酶解用木瓜蛋白酶,以肽得率为响应值.最终确定第一段酶解的最优条件为:酶(E)与底物(S)的质量比为0.3:100,温度为53℃,时间为5.90h;第二段酶解的最优条件为:E与S的质量比为0.12:100,温度为60℃,时间为5.60h.利用凝胶色谱测得最优条件下制备酶解液组分的相对分子质量范围介于714~8790之间,酶解液中肽含量超过50%(质量分数),与响应面模型所预测的肽得率(52.55%)相吻合.  相似文献   

2.
为了提高银鱼的附加值,采用蛋白酶水解其蛋白制备银鱼多肽.以水解度为优化指标,确定酸性蛋白酶为最佳用酶,研究了温度、pH、料液比和加酶量对水解度的影响.用Design-Expert 8.0软件进行响应面最佳条件优化,确定最适水解条件为:41℃,pH 4.0,料液比1∶52,酶解时间6h和加酶量2.3%.优化后水解度达到15.13%,为银鱼的综合利用提供了一种新方法.  相似文献   

3.
为优化鳙鱼活性多肽酶法制备工艺,分析了鳙鱼肉糜预处理温度和酶解温度对水解度的影响,确定了最佳的预处理条件为85℃水浴中加热预处理20 min,酶解温度设为55~75℃.经均匀设计实验优选和最优条件验证实验证实,以氮溶指数为指标的最优酶解条件为:酶解时间8.0 h,固液比1∶4.25,蛋白酶A用量3‰,酶解温度75℃,产物氮溶指数达80.54%;以多肽得率为指标的最优酶解条件为:酶解时间8.0 h,固液比1∶2,蛋白酶A用量3‰,酶解温度75℃,产物多肽得率达11.92%;以产物总抗氧化指数为指标的最优酶解条件为:酶解时间1.0 h,固液比1∶6,蛋白酶A用量3‰,酶解温度55℃,所得产物总抗氧化指数达87.42‰.  相似文献   

4.
徐曼  唐瑞华  龚军 《科技资讯》2014,12(23):112-113
选取果胶酶添加量、酶解温度和酶解时间三个因素进行中心组合设计,利用响应面法对其提取工艺进行优化研究.利用DesignExpert软件分析,结果表明最佳工艺条件为果胶酶用量0.18%,酶解时间91.9 min,酶解温度52℃.在此条件下,出汁率达到77.38%.  相似文献   

5.
为了提高虾类资源利用率以及加工副产物的风味,采用酶法水解技术对影响虾类加工副产物酶解程度的各个因素进行了研究,包括酶制剂及其用量、固液比、酶解时间、酶解温度和pH。通过一系列单因素实验和对酶用量、酶解时间、酶解温度的正交试验确定了最佳酶解条件。结果表明:最适酶制剂为由中性蛋白酶与风味蛋白酶复合而成的复合酶;酶用量分别为中性蛋白酶1 000 U/g,风味蛋白酶1 000 U/g;固液比为1:5,其中固体为20 g;最适合的酶解温度:第一段酶解为55℃,第二段酶解为50℃;酶解时间:第一段酶解为1 h,第二段酶解为3 h;最适pH为7.0。  相似文献   

6.
酒糟中蛋白质的提取工艺   总被引:1,自引:0,他引:1  
采用响应面法优化酒糟中蛋白质的提取条件.在单因素实验的基础上,选取醇碱比、固液比、提取时间为影响因子,应用Box-Behnken中心组合进行3因素3水平的实验设计,以蛋白质提取率作为响应值,进行响应面分析.结果表明,酒糟中蛋白质最佳提取条件为:提取时间87.2min,固液比(g/mL)为1:42.3,醇碱比为1:2.7,提取率预测值19.57%,验证值19.40%,与预测值的相对误差0.88%.  相似文献   

7.
研究纤维素酶法提取花生壳中木犀草素的最佳工艺条件。方法:采用紫外分光光度计在波长为n=408nm处测定木犀草素含量,以提取率为指标,分别考察了料液比、酶用量、酶解时间、酶解温度、回流时间对其含量的影响。纤维素酶酶解花生壳的最佳工艺条件:料液比1:8(w/v)、酶用量0.1%、酶解时间1.5h、酶解温度50℃、回流时间1.5h。  相似文献   

8.
小麦麸皮木瓜蛋白酶法提取工艺研究   总被引:2,自引:0,他引:2  
采用木瓜蛋白酶提取麦麸中的蛋白质,以蛋白提取率为指标,研究了温度、pH值、固液比、酶用量、提取时间对蛋白提取率的影响.用正交实验确定木瓜蛋白酶提取麦麸蛋白较适宜的条件为固液比为1∶10,提取时间为2.5 h,温度为55℃,pH值为7.0,酶与底物比为0.6%,提取率最高达到44.34%.  相似文献   

9.
采用了酶解辅助水法提取土茯苓总黄酮.以芦丁为标准品,用铝离子显色、紫外-可见分光光度法测定总黄酮含量.以总黄酮提取率为考察指标,通过单因素实验探讨酶用量、固液比、提取温度、提取次数对总黄酮提取率的影响,优化提取条件.结果表明最佳提取工艺条件为:酶用量2.0%、固液比例1:8、提取温度100℃、提取3次.最佳条件下,粗提物干粉得率为14.0%,干粉总黄酮含量为4.1%,总黄酮提取率为0.57%.  相似文献   

10.
采用响应面法优化丁二酸酐酯化修饰黑米色素的条件.以酯化率为衡量指标,选取酯化温度、pH、时间和液料比作为考察因素,在单因素实验基础上利用响应面法优化酯化工艺参数,依据回归分析确定各工艺条件的影响因子,用响应面和等高线分析各因素的显著性和交互作用.黑米色素酯化修饰最优工艺参数为:酯化温度63.℃,pH 6.0,时间4.0 h,液料比(mg﹕L)7.8﹕1.在该条件下酯化率为47.8%,经多次验证实验,在此条件下测得的酯化率为47%~48%.  相似文献   

11.
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   

12.
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   

13.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

14.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

15.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

16.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

17.
18.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

19.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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