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1.
本文分析了温度、酸度和时间三因素与毛发酸解胱氨酸提取率之间的相互关系,建立温度、酸度和时间对胱氨酸提取率的回归模型,其中时间和温度两个处理为线性模型,酸度为非线性模型.  相似文献   

2.
本文研究了以猪毛为原料,经过水解、赶酸、中和、结晶、精制提取出胱氨酸纯品;并从分离胱氨酸后的母液中,经过脱色、离子交换、浓缩、结晶、精制,制备出复合氨基酸.在本工艺条件下,胱氨酸产品的收率为4.8%,纯度在99%以上;复合氨基酸产品的收率为41%,纯度在83%以上.本文为扩大试验打下了基础.  相似文献   

3.
以重组人tPA蛋白为材料研究了精氨酸、精氨酸盐酸盐、半胱氨酸、胱氨酸对蛋白质复性效果的影响,重组tPA蛋白包涵体经尿素变性溶解后,在精氨酸、精氨酸盐酸盐、半胱氨酸、胱氨酸存在的条件下进行复性,结果表明,碱性的精氨酸在质量分数0.2%时可减少蛋白质凝聚,显著提高复性效果,tPA复性后的活性可提高50%以上,半胱氨酸单独使用具有类似β-巯基乙醇的作用,精氨酸盐酸盐和胱氨酸单独使用对复性无影响,而半胱氨酸和胱氨酸联合使用,有类似氧化-还原系统作用。可提高活性20%。  相似文献   

4.
从人发中连续提取亮氨酸和胱氨酸工艺初探   总被引:8,自引:1,他引:7  
介绍了一种从人发中连续提取亮氨酸和胱氨酸的新工艺。人发用盐酸水解后 ,将水解液减压赶酸 ,再直接加入邻二甲苯 - 4-磺酸沉淀亮氨酸 ,所得沉淀经氨解及后续的精制过程可得亮氨酸精品 ,沉淀亮氨酸后所得的母液按传统的工艺用液氨和得胱氨酸粗品 ,再经一次精制中和可得胱氨酸精品。亮氨酸和胱氨酸的收率分别可达 4 .9%和 7.8% ,产品质量符合日本味之素标准  相似文献   

5.
对以DL-2-氨基-?2-噻唑啉-4-羧酸(DL-2-amino-?2-thiazoline-4-carboxylic acid, DL-ATC)为底物原料, 经微生物酶法催化合成L-半胱氨酸, 并进一步氧化和分离纯化产物L-胱氨酸的生产工艺和条件进行了研究。建立了以恶臭假单胞菌TS1138 (Pseudomonas putida TS1138)全细胞为酶源, 反复多次催化底物合成L-半胱氨酸, 并以2.0%二甲基亚砜(DMSO)为氧化剂氧化生成L-胱氨酸, 进而通过001×7型阳离子交换树脂纯化胱氨酸的新工艺。采用高效液相色谱法考察该方法L-胱氨酸的总收率可以达到78.55%, 纯度为99.12%。该方法简单高效, 解决了酶稳定性差不能重复使用, 而固定化酶方法繁琐成本高的问题, 为我国L-半胱氨酸和L-胱氨酸的生产开辟一条新途径。  相似文献   

6.
利用毛发提取L-胱氨酸的生产工艺探讨   总被引:2,自引:0,他引:2  
在毛发提取胱氨酸的生产过程中,采用降低酸的用量(1:1.5)、蒸汽搅拌的方法进行迴流水解;经真空浓缩回收的盐酸,作为胱氨酸脱色之用;活性碳的再利用以及水解终点的确定等,即使胱氨酸平均收率达到8.30%以上,又使原辅料的消耗大大降低。产品主要质量指标达到日本AJINOMOTO Co.标准。  相似文献   

7.
用单扫描极谱法研究了胱氨酸在乙醇胺-HCl介质中产生的吸附还原波,并应用该方法测定了头发样品及胱氨酸片剂中胱氨酸的含量。结果表明,极谱波高与8.2×10~(-7)~1.2×10~(-5) mol/L的胱氨酸呈线性关系,检测限为3.5×10~(-7)mol/L,且多种氨基酸在较高浓度共存的情况下不干扰胱氨酸的测定。  相似文献   

8.
本文应用响应面分析的方法研究了酶用量、酶解温度和pH对薏苡仁油提取率的影响,并得到了最佳的提取条件。研究结果表明,酶用量为1.569%、酶解温度在47.7℃、酶解pH为4.75。响应的薏苡仁油提取率为10.948%。油脂质量分析结果表明,酶法处理并没有显著改变薏苡仁油的性质。  相似文献   

9.
恶臭假单胞菌TS1138转化生产L-胱氨酸的工艺研究   总被引:3,自引:1,他引:3  
对以DL-2-氨基-△2-噻唑啉-4-羧酸(DL-2-amino-△2-thiazoline-4-carboxylic acid,DL-ATC)为底物原料,经微生物酶法催化合成L-半胱氨酸,并进一步氧化和分离纯化产物L-胱氨酸的生产工艺和条件进行了研究.建立了以恶臭假单胞菌TS1138(Pseudomonas putida TS1138)全细胞为酶源,反复多次催化底物合成L-半胱氨酸,并以2.0%二甲基亚砜(DMSO)为氧化剂氧化生成L-胱氨酸,进而通过001×7型阳离子交换树脂纯化胱氨酸的新工艺.采用高效液相色谱法考察该方法L-胱氨酸的总收率可以达到78.55%,纯度为99.12%.该方法简单高效,解决了酶稳定性差不能重复使用,而固定化酶方法繁琐成本高的问题,为我国L-半胱氨酸和L-胱氨酸的生产开辟一条新途径.  相似文献   

10.
发酵茯苓菌丝体和天然茯苓多糖的研究   总被引:8,自引:0,他引:8  
本文对发酵茯苓菌丝体和天然茯苓中多糖的提取分离进行了研究,并分别测定了二者总多糖的提取率及总糖的平均含量。发酵茯苓菌丝体和天然茯苓中总多糖的提取率分别为24.47%和82.93%;发酵茯苓菌丝体和天然茯苓总糖的平均含量分别为45.17%和87.24%。  相似文献   

11.
本文介绍了用不同方法处理的猪毛分别在实验室和工厂提取胱氨酸,证明胱氨酸的得率和猪毛质量有关。含杂15%左右的干打猪毛大生产胱氨酸的得率平均4.4%;不含杂质的猪座子毛胱氨酸得率平均达6.71%探讨了清除猪毛杂质,提高猪毛质量对胱氨酸生产的重要意义。  相似文献   

12.
野薄荷叶腺毛的发育形态学研究   总被引:6,自引:1,他引:5  
研究了分布于我国东北部的野薄荷叶表面腺毛的结构和发育。主要腺毛有两种:多细胞盾状腺毛和弯曲单细胞头状腺毛。多细胞盾状腺毛由1个基细胞,1个柄细胞和一个由8-12个分泌细胞构成的头部组成。单细胞头状腺毛由1个基细胞,1个柄细胞和一个分泌细胞头部构成。  相似文献   

13.
火炬树腺毛的形态结构和发育的研究   总被引:8,自引:0,他引:8  
研究了火炬树(RhustyphinaTorner.)叶柄腺毛的形态结构和发育过程,结果表明,其腺毛起源于叶柄的表皮细胞,每个腺毛都由1个基细胞、3个柄细胞和分泌细胞组成的头部3部分组成。  相似文献   

14.
We are using patterns of cuticle specialization in Drosophila larvae as models to investigate the molecular, genetic, and developmental bases of morphological evolution. Members of the virilis species group differ markedly from one another in the distribution of hairs on the dorsal surface of first instar larvae. In particular, characteristic bands of hairs cover about 20% of each trunk segment in some species but about 70% in others. These major types do not correlate with recently proposed phylogenetic relationships, suggesting that similar phenotypes have arisen independently in different lineages. The patterns of expression of several genes that control or reflect intrasegmental patterning are indistinguishable in species with very different cuticle morphologies. We conclude that, in this case, morphology probably has evolved via altered response to a conserved molecular prepattern.  相似文献   

15.
徐文龙 《人类学学报》1989,8(4):367-371
本文观察了91名中国人头发的截面特征,包括短径、长径、截面指数和截面积,并与其他种族进行了比较。发现中国人头发最粗,截面形状较接近圆形,唯长径显著小于黑人。本文还对头发截面特征的性别差异和个体差异进行了变差分析。根据本文的观察结果,对司法鉴定中头发的形态学检验问题提出了初步意见。  相似文献   

16.
Treatment of excessive hair growth is an important issue in both dermatological and cosmetic practice. In contrast to treatments with medication, most physical methods are treatments that focus on the hair follicle. To obtain insight in the failure behavior of the anchorage of hairs, hairs were extracted (in vitro) from pig skin at a speed of 0.1mm/s, one at a time. The pulling force and tweezers displacement were recorded. The extracted hairs were classified with respect to the phase in the growing cycle: anagen (growing phase), telogen (resting phase) or other (catagen phase or unable to determine). The anagen hairs showed a different relation between the tweezers displacement and the pulling force than the telogen hairs. Moreover, the maximum force that could be applied before a hair was extracted proved to be lower for anagen hairs than for telogen hairs (0.36N, 1.8N, respectively). The extracted hair length, defined as the part of the hair that had been embedded in the skin which was extracted, was higher for anagen hairs than for telogen hairs (4.8mm, 3.0mm, respectively). Removing proximal skin tissue and the embedded parts of the anagen hair (root) resulted in a change of the extraction curves. The results indicate that two phenomena play a role in the anchorage of anagen hairs. We have proposed a model for the extraction of an anagen hair that has been based on these results: first the interface between hair and skin that is located around the inner root sheath (IRS) starts to fail, followed by failing of the hair itself in the region where the hair keratinizes.  相似文献   

17.
杜鹃花属的子叶形态分类   总被引:4,自引:0,他引:4  
张长芹   《广西植物》1993,13(1):12-25
通过对杜鹃花属中4个亚厲104种或变种的广叶形态观察发现:1、杜鹃花属中4个亚属间的子叶形态差异较大,杜鹃花鳞片的有无从子叶上就可以清楚地看出。2、常绿无鳞杜鹃亚属Subgenus Hymenanthes(BL)K.Koch的子叶边缘多只腺体状毛或白、棕色单毛,极少无毛。背面多为暗紫红色或为灰白及灰绿色,叶片多具侧脉少数仅具中脉;有鳞杜鹃亚屈SubgenusRhododendron的子叶边缘无毛或仅少数有白色单毛,背面基部或边缘具可数片,背面多为灰绿色极少暗紫色,叶片多具中脉少有侧脉;映山红亚属Subgeuus Tsutsusi(Sweet)Pojar-kova的子叶边缘无毛或仅一种有毛,背面灰绿色,具侧脉;马银花亚属Subgentis AzaleaslrumPlanch.的子叶近圆形,边缘无毛,具侧脉3-4对,背面白绿色。 有关杜鹃花属子叶形态研究,国外虽有报道,但仅涉及少数种类,最多的也不超过35种,其中野生种仅有7种,其代表性显然是不够的。在国内,有关杜鹃花属于叶形态分类方面的研究目前尚未见报道。杜鹃花是久负盛誉的世界名花,云南是杜鹃花的分布中心之一。观察杜鹃花和子叶形态并进行分类,不仅为杜鹃花的系统发育及杜鹃花属的分类提供佐证而且为杜鹃花的育种提供一个早期的鉴定指标。  相似文献   

18.
A field study to determine the precise times of year at which three intertidal species of Fucus start to produce hyaline hairs and cease producing such hairs was conducted on the Isle of Man, U.K. Hairs were first observed during February, and within 6 days of their initial appearance, all tagged plants of all species at all tidal heights on the shore possessed hairs. Hair production continued until the beginning of October, at which time Fucus plants growing at the lowest stations (+ 3.0 m) had glabrous apical growth. Hair production continued later into the year for plants growing higher on the shore, and it was not until mid-November that glabrous apical growth was observed in all plants. Phosphate uptake rates of pilose (hairy) and glabrous (hairless) apical sections were measured in November 1988 for F. spiralis L. and in January 1989 for F. spiralis and F. serratus L., at phosphate concentrations ranging from 0.8 μM (ambient seawater) to 9.0 μM. In ambient seawater, pilose plants of F. spiralis removed phosphate 2–3 times faster than glabrous plants, whereas the uptake rates of pilose plants of F. serratus were about 50% greater than those of glabrous plants. The differences between uptake rates of pilose and glabrous plants of both species were smaller or nonsignificant at higher phosphate concentrations. The field and laboratory data are consistent with the hypothesis that hairs are formed in Fucus as a response to increased nutrient demand and that hairs facilitate the uptake of nutrients from seawater at concentrations typical of natural situations.  相似文献   

19.
We analysed the abundance, spatial distribution and soil contact of wheat roots in dense, structured subsoil to determine whether incomplete extraction of subsoil water was due to root system limitations. Intact soil cores were collected to 1.6 m below wheat crops at maturity on a red Kandosol in southern Australia. Wheat roots, remnant roots, soil pores and root–soil contact were quantified at fresh breaks in the soil cores. In surface soil layers (<0.6 m) 30–40% of roots were clumped within pores and cracks in the soil, increasing to 85–100% in the subsoil (>0.6 m), where 44% of roots were in pores with at least three other roots. Most pores contained no roots, with occupancy declining from 20% in surface layers to 5% in subsoil. Wheat roots clumped into pores contacted the surrounding soil via numerous root hairs, whereas roots in cracks were appressed to the soil surface and had very few root hairs. Calculations assuming good root–soil contact indicated that root density was sufficient to extract available subsoil water, suggesting that uptake is constrained at the root–soil interface. To increase extraction of subsoil water, genetic targets could include increasing root–soil contact with denser root hairs, and increasing root proliferation to utilize existing soil pores.  相似文献   

20.
Vigilant L 《Biological chemistry》1999,380(11):1329-1331
Hair can be a valuable source of DNA for the noninvasive study of human and nonhuman populations. However, hairs contain extremely small quantities of DNA, making the method used to extract the DNA of paramount importance. This study compares the effectiveness of 4 different methods of DNA extraction from shed chimpanzee hair, as measured by the ability to amplify mtDNA targets using PCR. The most successful method is also the simplest, requiring only digestion of the root end in a buffer compatible with subsequent PCR without a prior purification or extraction step. Strategies to non-specifically preamplify the template are not successful with DNA from stored shed hairs.  相似文献   

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