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1.
【目的】分离鉴定雪白白僵菌红色素,分析红色素与环孢菌素A对底物缬氨酸的竞争和相互影响。【方法】对红色素进行分离纯化,利用UV、IR和ESI-MS对红色素进行初步鉴定。采用缬氨酸分批补料培养,通过控制溶氧水平,以及添加红色素,分析红色素与环孢菌素A合成之间的竞争关联及相互影响。【结果】经鉴定,雪白白僵菌红色素分子式为C15H10O5,推测为含有芳环结构的蒽醌类化合物。在补加缬氨酸和高DO条件下,环孢菌素的产量高于低DO水平,相反红色素在低DO条件下合成量大于高DO水平。在不补加缬氨酸条件下,实验结果与补加缬氨酸培养一致,但是红色素和环孢菌素A的产量都显著降低。进一步添加外源纯化的红色素时,随着添加量的增加出现了环孢菌素A合成先减弱后增加的变化。【结论】发现并证实了雪白白僵菌红色素与环孢菌素A合成都以缬氨酸为共同底物,但两者的途径又相互独立。  相似文献   

2.
肖黄栌红色素的理化性质研究   总被引:3,自引:0,他引:3  
本文研究了肖黄栌红色素的提取 ,并研究了不同糖浓度、温度、光照、紫外线、Na2 HPO4 -KH2 PO4 缓冲液、维生素C、氧化剂H2 O2 、还原剂Na2 SO3 等对肖黄栌红色素稳定性的影响。结果表明 ,肖黄栌红色素适应的pH范围较广、抗热、抗氧化、抗还原、耐糖、耐维生素C。因而是一种有重要开发价值的天然红色素  相似文献   

3.
辣椒红色素是红辣椒果实中的四萜类天然色素,着色效果好、安全性高,广泛应用于食品、药品、化妆品和饲料工业.概述了辣椒红色素的理化性质及其在辣椒果实成熟过程的动态变化,阐述了辣椒红色素的提取方法和在各领域应用,并展示了其广阔的应用前景.  相似文献   

4.
新疆的郁金香属种质资源   总被引:1,自引:0,他引:1  
谭敦炎 《生命世界》2001,(6):F003-F003,1
郁金香是百合科郁金香属(Tulipa)植物的总称,是举世公认的名贵花卉,被誉为“花卉王国中的皇后”,深受人们的喜爱。新疆是世界郁金香属植物的自然分布区之一,也是中国的集中分布区,目前已知有该属植物13种,占世界种类的10%左右。近几年来,在国家自然科学基金的资助下,我们对新疆产郁金香进行了深入调查及引种栽培工作,建立了13种约80个居群的野生郁金香属植物种质资源圃,并对其生物学特性进行了系统全面的观察。在此仅对这13种郁金香的分布及园艺性状做一简介,供读者参考。新疆郁金香(T.sinkiangensis)特有种。…  相似文献   

5.
龙葵红色素热效应的研究   总被引:1,自引:0,他引:1  
本文研究了温度对龙葵红色素的影响。结果表明:龙葵红色素的热降解遵从一级反应动力学规律,热降解速度随温度升高而加快。同时建立了60℃、80℃、100℃下的回归方程,求出了这三个温度下的半衰期和热降解的速度常数,从而为龙葵红色素的开发和利用提供了科学依据。  相似文献   

6.
爬山虎红色素的大孔树脂吸附和分离及理化性质研究   总被引:4,自引:0,他引:4  
本文比较了六种不同型号的大孔树脂对爬山虎红色素的吸附能力,筛选其中最佳的HPD600树脂作为爬山虎红色素的吸附和分离的树脂;用甲醇作为洗脱剂,洗脱效果好;研究了食品中几种常见的共存物、几种金属离子、氧化剂、温度及光等对爬山虎红色素稳定性的影响。  相似文献   

7.
胭脂萝卜红色素的研制   总被引:3,自引:0,他引:3  
本文报道了胭脂萝卜红色素的生产工艺,并结合生产方法与相关条件开展讨论。同时报道了胭脂萝卜红色素的三种物理性状,即溶解性、坚牢度、染着性  相似文献   

8.
为了探讨超声波对盐地碱蓬红色素提取效果的影响,为进一步提取纯化盐地碱蓬红色素提供一定的理论依据,通过单因素和正交实验,研究了不同提取时间、温度、液固比和功率下超声波辅助对盐地碱蓬红色素提取的影响.结果表明:各因素对红色素提取效果的影响程度依次为液田比>温度>功率>时间;最佳提取工艺条件为提取时间50 min,提取温度50℃,液固比15 mL/g,超声功率800 W.超声波对盐地碱蓬红色素的提取具有一定的促进作用.  相似文献   

9.
康乃馨红色素的提取研究   总被引:4,自引:0,他引:4  
研究了用树脂吸附和分离康乃馨红色素 ,比较了 4种树脂对康乃馨红色素的吸附。结果表明 ,四种树脂对康乃馨红色素的吸附效果均较好。本实验选用AB 8树脂作吸附剂。洗脱剂用 6 0 %的乙醇 ,洗脱效果好 ,产品杂质少 ,色价高 ,且使用 2 0次后其吸附性能稳定 ,所以选用AB 8树脂吸附康乃馨红色素  相似文献   

10.
郁金香种质资源遗传多样性的ISSR分析   总被引:1,自引:0,他引:1  
本研究利用22个ISSR引物对5个新疆野生郁金香种和19个郁金香栽培品种进行ISSR分析。扩增得到195条谱带,其中多态位点为191个,多态性位点百分比为97.95%。24个郁金香材料检测等位基因数(na~*)平均为1.979 5,有效等位基因数(ne~*)在1.000 0~2.000 0之间,平均为1.432 3;Nei's基因多样性指数(h~*)在0.000 0~0.500 0之间,平均为0.262;Shannon's信息指数(I~*)在0.000 0~0.693 1之间,平均为0.407 8;研究实验反映出郁金香遗传变异水平较高,具有丰富的遗传多样性。聚类实验表明:24个郁金香材料在阈值为0.54处被聚类为A和B两大类,在阈值为0.63处除伊犁郁金香(T. iliensis)以外,其余四个郁金香野生种与常规栽培品种被单独聚类,说明野生种与栽培品种之间遗传距离较远,且大部分栽培品种之间亲缘关系较近。5个野生郁金香种中垂蕾郁金香(T. patens)、柔毛郁金香(T. buhseana)、天山郁金香(T. tianschanica)与栽培品种之间的遗传距离均在0.4以上,可以考虑作为杂交育种的材料。本研究为合理利用我国野生郁金香种质资源提供分子水平上的研究基础,并为日后郁金香杂交育种工作中亲本组合的选择提供一定的理论参考。  相似文献   

11.
A lectin was isolated from tulip (Tulipa) bulbs by affinity chromatography on fetuin-agarose and partially characterized. The tulip lectin is a tetrameric protein composed of four identical subunits of Mr 28 000, which are not held together by disulphide bonds. It is not glycosylated and has an amino-acid composition typified by a high content of asparagine-aspartic acid, leucine, glycine and serine. Tulip lectin agglutinates human red blood cells, but has a much higher specific activity with rabbit erythrocytes. In hapten-inhibition assays with the latter type of red blood cell the lectin exhibits a complex specificity, whereas its agglutination with human erythrocytes is readily inhibited by N-acetylgalactosamine, lactose, fucose and galactose.Abbreviations DEAE diethylaminoethyl - PBS phosphate-buffered saline - TL Tulipa lectin - Mr relative molecular mass - SDS-PAGE sodium dodecyl sulphate-polyacrylamide gel electrophoresis  相似文献   

12.
Seven captive-born lemurs (Lemur fulvus) at the Duke University Primate Center were presented with leaves of different maturity from five species of North Carolina trees. The animals demonstrated three distinct behaviors toward the novel plant material. They sniffed, tasted, and/or ingested it. New leaves were sniffed, but little tasting and ingestion was observed. Intermediate pine needles were sniffed and ingested but little tasted. Mature leaves were sniffed equally, but the mature leaves of tulip trees and honeysuckle were tasted significantly more than pine, sweetgum, and red maple. Pine, sweetgum, and red maple were ingested significantly more than tulip trees and honeysuckle. Male lemurs ate significantly more mature pine needles and new sweetgum leaves than did the females. Chemical analysis of these plant materials indicated that the new and mature leaves of tulip tree and honeysuckle contained alkaloids. Captive-born lemurs apparently use their sense of smell and taste in choosing what to eat and seem just as capable as free-ranging animals in finding food when faced with the chemical defenses that protect trees from insect predation.  相似文献   

13.
The diversity and distribution of the genus Tulipa in Uzbekistan are discussed; 34 taxa of Tulipa are recognized in Uzbekistan. The taxa were mapped using GIS software and their distributions were analyzed. Six species are endemic to the country. A national check‐list of Tulipa was created based on the classification developed by Zonneveld (2009). ‘Hot spot’ areas of tulip diversity in Uzbekistan are western Tien‐Shan (18 taxa), the western Pamir–Alay mountains (18 taxa) and the Turan lowland (5 taxa). An assessment of rare tulip species according to IUCN red list categories and criteria was performed for the first time for Uzbekistan. Evaluation of the latest classification of Tulipa clearly shows that further studies are required to arrive at a natural classification of the genus.  相似文献   

14.
Diurnal variation in petiole specific hydraulic conductivity and simultaneous measurements of leaf water potential were recorded in red maple, tulip tree and fox grape. Petiole specific conductivity was determined from in situ measurements of water flow into the distal (leaf‐bearing) end of an attached petiole as a function of applied hydrostatic pressure and petiole dimensions. The hydraulic properties of the petiole dominated the measurements, indicating that this technique can be used for rapid estimates of petiole hydraulic conductivity. There was a significant decrease in petiole specific conductivity associated with increasingly more negative leaf water potentials in maple and tulip tree, but not in grape. Petiole specific conductivity increased during the afternoon while the plant was actively transpiring and the xylem sap was under tension. The recovery of petiole conductivity during the afternoon suggests that hydraulic conductivity reflects a dynamic balance between a loss of hydraulic conductivity with increasing water stress, and its restoration as tension within the xylem decreases. Three experimental manipulations were applied to red maple and tulip tree to examine the sensitivity of diurnal changes in petiole conductivity to various physiological perturbations. Both phloem girdling and application of HgCl2 to the transpiration stream resulted in a marked decrease in the degree to which petiole specific conductivity recovered as xylem tension relaxed during the afternoon. Delivery of a surfactant to the xylem, however, did not significantly alter the relation between leaf water potential and petiole hydraulic conductivity.  相似文献   

15.
Pure cultures of six races of Ditylenchus dipsaci derived from a single female, namely, lucerne race (LR), red clover race (RCR), white clover race (WCR), narcissus race (NR), tulip race (TR) and oat race (OR) were inoculated into eight plant species growing in pots. Onion was host to all six races, and tulip to all except RCR, whereas lucerne was susceptible only to LR and slightly to WCR. Hyacinth was not very susceptible to any race. The TR and OR were the most polyphagous. Severe symptoms were not necessarily associated with large nematode populations. Parthenogenesis did not occur. Ten fertile hybrids between races were produced and the host range of five of these was tested. On average the hybrids multiplied less than their parent races and their host ranges showed no relationship to those of their parent races. RCR and TR inoculated together into tulip produced significantly fewer nematodes than did TR alone and more than RCR alone. Mixed populations of races occur in nature which are probably a mixture of parental races, their hybrids and back-crosses. Repeated back-crossing of the hybrids with parental types and the slower multiplication of the hybrids is an explanation for the variation in host range of known races and the failure to record new races.  相似文献   

16.
A specific self-immobilization biomembrane-surface liquid culture (SIBSLC) was developed to overproduce a potential penicillium red pigment. Statistic analysis shows that both glucose concentration and membrane diameter are important factors influencing the yield of red pigment. After the optimization using central composite experimental design, the maximum yield of red pigment in shake flask reaches 4.25?g/l. The growth of strain HSD07B consists of three phases, and the pigment secreted in the decelerated phase, is originated from the interior of biomembrane where glucose exhaustion occurs. In addition, the batch and continuous SIBSLC were conducted for production of the pigment, and the latter was more competitive in consideration of the fact that it not only increased 61.5?% of pigment productivity, but also simplified the production process. Moreover, the pigment produced by SIBSLC is potentially acceptable for food applications although it is distinguished from the co-cultured red pigment we reported previously in components.  相似文献   

17.
Blue cone monochromatism (BCM) is a rare X-linked colour vision disorder characterized by the absence of both red and green cone sensitivity. Most mutations leading to BCM fall into two classes of alterations in the red and green pigment gene array at Xq28. In one class the red and green pigment genes are inactivated by deletion in the locus control region. In the second class genetic rearrangements have created an isolated pigment gene that carries an inactivating point mutation. Here we describe a clinical case of BCM caused by a new mutation where exon 4 of an isolated red pigment gene has been deleted. The finding represents the first intragenic deletion yet described among red and green pigment genes. Received: 29 December 1995 / Revised: 30 May 1996  相似文献   

18.
Molecular evolution of human visual pigment genes   总被引:9,自引:1,他引:8  
By comparing the published DNA sequences for (a) the genes encoding the human visual color pigments (red, green, and blue) with (b) the genes encoding human, bovine, and Drosophila rhodopsins, a phylogenetic tree for the mammalian pigment genes has been constructed. This evolutionary tree shows that the common ancestor of the visual color pigment genes diverged first from that of the rhodopsin genes; then the common ancestor of the red and green pigment genes and the ancestor of the blue pigment gene diverged; and finally the red and green pigment genes diverged from each other much more recently. Nucleotide substitutions in the rhodopsin genes are best explained by the neutral theory of molecular evolution. However, important functional adaptations seem to have occurred twice during the evolution of the color pigment genes in humans: first, to the common ancestor of the three color pigment genes after its divergence from the ancestor of the rhodopsin gene and, second, to the ancestor of the red pigment gene after its divergence from that of the green pigment gene.  相似文献   

19.
Wounds are common clinical entities of life which may be subacute or acute. Wound healing is a complex biochemical process where the cell structures are restored to normalcy, which depend on cell proliferation and migration, basically fibroblast cell. The present investigation was undertaken to evaluate the healing efficacy of red pigment isolated from marine isolate Vibrio sps on experimental wounds in albino rats. The red pigment was applied topically, twice daily for 14 days. Treatment with framycetin ointment was used as reference control. The red pigment treated group showed faster reduction in wound area in comparison with control and framycetin ointment treated groups. In conclusion, red pigment possesses significant healing potential in wounds and has a positive influence on the different phases of wound repair.  相似文献   

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