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1.
从木通科木通属植物白木通[Akebia trifolinta (Thunb.) Koidz. var. australis(Dies)Rehd]的种子(蓣知子)抗肿瘤活性的乙醇提取物中以硅胶层析等方法分得一种三萜皂甙。经波谱分析及酸碱水解确定了其化学结构,命名为:3-O-α-L-吡喃阿拉伯糖常春藤皂甙元-28-O-β-D吡喃葡萄糖-(1→6)-β-D-吡喃葡萄糖甙(即Saponin D),为首次自该植物中获得。  相似文献   

2.
银耳孢子多糖TF-A、TF-B、TF-C的分离、纯化及组成单糖的鉴定   总被引:25,自引:0,他引:25  
用固体培养法获得的中国福建产银耳孢子(Tremella fucifromis Berk)经热水提取,三氯醋酸-正丁醇除杂蛋白、透析、乙醇沉淀,再通过DEAE-Dextran-Gel A-25柱层析分离和Sephadex G-200柱层析纯化,得到三种白色粉末状的多糖,命名为TF-A、TF-B及TF-C。用聚丙烯酰胺凝胶电泳,葡聚糖凝胶柱层析及气相色谱分析证明三者均为均一体。TF-A、TF-B及TF-C用酸完全水解,经纸层析和气相色谱分析表明:TF-A由L-岩藻糖、L-阿拉伯糖、D-木糖、D-甘露糖、D-半乳糖和D-葡萄糖组成,摩尔比为葡萄糖:甘露糖:木糖:岩藻糖:阿拉伯糖:半乳糖=1.06:1.0:0.33:0.29:0.037:0.75,TF-B及TF-C都由L-岩藻糖、L-阿拉伯糖、D-木糖、D-甘露糖、D-葡萄糖和葡萄糖醛酸组成,摩尔比分别为:葡萄糖:甘露糖:木糖:岩藻糖:阿拉伯糖:葡萄糖醛酸=0.16:1.0:0.28:0.73:0.036:0.19和0.086:1.0:0.37:0.75:0.058:0.37。  相似文献   

3.
九里香(Murraya Paniculata L.Jack)皮部经热水提取、乙醇沉淀、SephadexG—100柱层析分离、磷酸氢钙吸附、酸溶,再通过Sephadex G-200柱层析纯化,得到灰白色粉末状九里香蛋白多糖。总糖含量为52.1%(其中葡萄糖醛酸含量为10.9%),蛋白质含量为20.0%。九里香蛋白多糖去蛋白后,即得九里香多糖,总糖含量为88.2%(其中葡萄糖醛酸含量为20.0%),经纸层析和聚丙烯酰胺凝胶园盘电泳鉴定为单一斑点和单一区带。平均分子量约为1.7×10~(-5)。组成单糖的摩尔比为葡萄糖:露甘糖:木糖:阿拉伯糖:岩藻糖:葡萄糖醛酸=1.0:0.40:0.16:0.17:0.20:0.48.  相似文献   

4.
黄蜀葵的化学成分研究   总被引:15,自引:0,他引:15  
黄蜀葵花对多种口腔炎症有止痛作用,治疗慢性气管炎疗效亦较好。从其酒精浸膏中分离出五种黄酮类成分,经光谱分析、衍生物的制备、酸水解以及物理化学常数的测定,分别鉴定为槲皮素-3-洋槐糖甙、槲皮素-3′葡萄糖甙、金丝桃甙、槲皮素及杨梅素。其中槲皮素-3-洋槐糖甙及槲皮素-3′-葡萄糖甙在本属植物中系首次分得。  相似文献   

5.
皂角菌经水提醇沉除蛋白质,精制得多糖,并对多糖成分进行了定性、定量分析。SephadexG-150柱层析证明为均一性多糖,糖含量为22.62%,红外光谱证明为β-甙键聚合,比旋光度为+28.89°,纸层析检测多糖由葡萄糖组成  相似文献   

6.
梅花‘南京红’花色色素花色苷的分子结构   总被引:8,自引:0,他引:8  
经特殊颜色反应、纸层析、紫外 -可见光谱、高效液相色谱、气相色谱和核磁共振波谱分析表明 :梅花‘南京红’花色色素的 3种主要花色苷分别是 :花青素 3 氧 (6″ 氧 α 吡喃型鼠李糖基 β 吡喃型葡萄糖 )苷 ,花青素 3 氧 (6″ 氧 没食子酰 β 吡喃型葡萄糖 )苷和花青素 3 氧 (6″ 氧 反式阿魏酰 β 吡喃型葡萄糖 )苷。花青苷在根本上决定着‘南京红’的粉红色花色 ,并可能强化‘南京红’的耐寒能力 ,也奠定了开发和利用该种花色色素的基础。  相似文献   

7.
本研究用葡萄糖甘油琼脂培养基经28℃培养代替葡萄糖肉汤,提高了诺卡氏菌的产量。用前述方法提取的 N-r-CWS 制剂,经无菌,毒性、过敏试验均合乎标准。纸层析证明 N-r-CWS 含有阿拉伯糖和半乳糖。高压液相色谱证明N-r-CWS 含有丙氨酸、缬氨酸、苏氨  相似文献   

8.
采用高效液相色谱法建立同时测定杜仲中松脂醇二葡萄糖甙(PDG)和丁香脂素二糖甙(SDG)的方法。色谱条件为:色谱柱为VP-ODSC18柱(150mm×4.6mm,预柱10mm×4.6mm);流动相为甲醇∶水(v/v)=30∶70;流速1mL/min;柱温25℃;进样量10μL;检测波长227nm。松脂醇二葡萄糖甙在和丁香脂素二糖甙进样量分别在30.8~154.0μg/mL之间,SDG的进样量在26.4~88.0μg/mL之间时,线性关系良好;平均回收率分别为99.8%,98.6%。结果表明该方法快速、准确、简单,可用于杜仲中松脂醇二葡萄糖甙和丁香脂素二糖甙的定量测定。  相似文献   

9.
长松萝多糖的研究   总被引:6,自引:0,他引:6  
长松萝经三氯甲烷抽提后风干,用热水提取,乙醇沉淀,经微晶纤维素柱层析纯化,得白色粉末状多糖USL。USL经Sephadex G-150柱层析证明为一组均匀多糖,其糖的含量为89.52%。经气相色谱检定,由阿拉伯糖(Ara)、木糖(Xy1)、甘露糖(Man)、葡萄糖(Glc)聚合而成,其克分子比为0.31:0.05:1.00:18.10。经Sephadex G-200柱层析测定,平均分子量为30×10~4,经高碘酸氧化,Smith降解,有甲酸、丙三醇、赤藓醇生成。红外光谱在896cm-~1处有吸收,证明USL多糖结构主要以β(1→4)、β(1→6)甙键连接而成的杂多糖。  相似文献   

10.
本文研究了影响紫背天葵试管苗花青甙含量的某些因子,即培养基成分,pH、糖、维生素B_2和椰乳。生长在1/2SH培养基上的苗,它的花青甙含量比在1/2MS培养基上的增加33%。对花青甙含量和苗的生长都有利的培养基pH是5.8。糖的种类对花青甙含量有明显的影响,在含果糖培养基中生长的苗,其花青甙浓度比其他糖中的高,可比蔗糖的增加52%,但培养物生长量很低,仅为蔗糖的64%。葡萄糖对紫背天葵花青甙的含量和生长都有良好的作用。上述两方面都比在蔗糖中的增加近30%;对花青甙含量的葡萄糖适宜浓度为4%。看来,糖对花青甙浓度的影响与培养物的生长速度之间有某些关系。椰乳对苗的生长和花青甙含量均有明显促进作用,分别比对照增加180%和50%。  相似文献   

11.
Photoheterotrophic growth of a filamentous cyanobacterium Calothrix sp. PCC 7601, which is capable for complementary chromatic adaptation, in the presence of glucose was accompanied by changes in the content of phycobiliproteins. Glucose, a source of energy and a metabolism regulator, differently affected the level of major phycobilisome pigments, phycocyanin (PC) and phycoerythrin (PE) in the cells. When red light enhanced PC synthesis, glucose enhanced it additionally. When green light suppressed PC synthesis, glucose did not affect it. Under both light regimes, glucose inhibited PE synthesis. Thus, glucose oppositely affected the content of two major phycobiliproteins. Glucose not only affected the ratio between phycobiliproteins but also decreased the content of carotenoids, inhibited activity of photosystem II, and affected cell sizes. A stereochemical analog of glucose, 2-deoxy-D-glucose, induced effects similar to those of glucose. A comparison with the effects of red and green light demonstrated that glucose acted on Calothrix similarly to red light and oppositely to green light.Translated from Fiziologiya Rastenii, Vol. 52, No. 2, 2005, pp. 266–273.Original Russian Text Copyright © 2005 by Lebedeva, Boichenko, Semenova, Pronina, Stadnichuk.This revised version was published online in April 2005 with a corrected cover date.  相似文献   

12.
Eye pigments of normal and mutant types of D. melanogaster have been extracted with water and fractionated by chromatographic adsorption on powdered talc. Spectra of all the fractions obtainable in solution have been measured and the general chemical behavior of the pigments is described. Two chemically distinct groups of pigments are found, to be identified with the earlier designated red and brown components. The red component in the wild-type eye contains three well defined pigments, two of them capable of further subdivision so that the total number of fractions obtained is five. There is also present a brown component pigment which could not be treated quantitatively by the methods employed. All members of the wild-type red component are found in cinnabar eyes, unaccompanied by the brown component. Conversely, brown eyes contain a pigment indistinguishable from the wild-type brown component, virtually alone. In sepia eyes, one red component and two brown component pigments can be distinguished, all three pigments differing from those of wild-type eyes. Pigments apparently identical with those found in wild-type melanogaster eyes have also been found in D. virilis.  相似文献   

13.
In this study we have analyzed the effects of variations in the concentrations of oxygen and of blood sugar on light sensitivity; i.e. dark adaptation. The experiments were carried out in an air-conditioned light-proof chamber where the concentrations of oxygen could be changed by dilution with nitrogen or by inhaling oxygen from a cylinder. The blood sugar was lowered by the injection of insulin and raised by the ingestion of glucose. The dark adaptation curves were plotted from data secured with an apparatus built according to specifications outlined by Hecht and Shlaer. During each experiment, observations were first made in normal air with the subject under basal conditions followed by one, and in most instances two, periods under the desired experimental conditions involving either anoxia or hyper- or hypoglycemia or variations in both the oxygen tension and blood sugar at the same time. 1. Dark adaptation curves were plotted (threshold against time) in normal air and compared with those obtained while inhaling lowered concentrations of oxygen. A decrease in sensitivity was observed with lowered oxygen tensions. Both the rod and cone portions of the curves were influenced in a similar way. These effects were counteracted by inhaling oxygen, the final rod thresholds returning to about the level of the normal base line in air or even below it within 2 to 3 minutes. The impairment was greatest for those with a poorer tolerance for low O2. Both the inter- and intra-individual variability in thresholds increased significantly at the highest altitude. 2. In a second series of tests control curves were obtained in normal air. Then while each subject remained dark adapted, the concentrations of oxygen were gradually decreased. The regeneration of visual purple was apparently complete during the 40 minutes of dark adaptation, yet in each case the thresholds continued to rise in direct proportion to the degree of anoxia. The inhalation of oxygen from a cylinder quickly counteracted the effects for the thresholds returned to the original control level within 2 to 3 minutes. 3. In experiments where the blood sugar was raised by the ingestion of glucose in normal air, no significant changes in the thresholds were observed except when the blood sugar was rapidly falling toward the end of the glucose tolerance tests. However, when glucose was ingested at the end of an experiment in low oxygen, while the subject remained dark adapted, the effects of the anoxia were largely counteracted within 6 to 8 minutes. 4. The influence of low blood sugar on light sensitivity was then studied by injecting insulin. The thresholds were raised as soon as the effects of the insulin produced a fall in the blood sugar. When the subjects inhaled oxygen the thresholds were lowered. Then when the oxygen was withdrawn so that the subject was breathing normal air, the thresholds rose again within 1 to 2 minutes. Finally, if the blood sugar was raised by ingesting glucose, the average threshold fell to the original control level or even below it. 5. The combined effects of low oxygen and low blood sugar on light sensitivity were studied in one subject (W. F.). These effects appeared to be greater than when a similar degree of anoxia or hypoglycemia was brought about separately. 6. In a series of experiments on ten subjects the dark adaptation curves were obtained both in the basal state and after a normal breakfast. In nine of the ten subjects, the food increased the sensitivity of the subjects to light. 7. The experiments reported above lend support to the hypothesis that both anoxia and hypoglycemia produce their effects on light sensitivity in essentially the same way; namely, by slowing the oxidative processes. Consequently the effects of anoxia may be ameliorated by giving glucose and the effects of hypoglycemia by inhaling oxygen. In our opinion, the changes may be attributed directly to the effects on the nervous tissue of the visual mechanism and the brain rather than on the photochemical processes of the retina.  相似文献   

14.
The production of red pigments and citrinin by Monascus purpureus CCT3802 was investigated in submerged batch cultures performed in two phases: in the first phase, cells were grown on glucose, at pH 4.5, 5.5 or 6.5; after glucose depletion, pH was adjusted, when necessary, to 4.5, 5.5, 6.5, 7.0, 8.0 or 8.5, for a production phase. The highest total red pigments absorbance of 11.3 U was 16 times greater than the lowest absorbance and was achieved with growth at pH 5.5, followed by production at pH 8.5, which causes an immediate reduction of the intra cellular red pigments from 75% to 17% of the total absorbance. The lowest citrinin concentration, 5.5 mg L−1, was verified in the same culture while the highest concentration, 55 mg L−1, was verified in cultures entirely carried out at pH 5.5. An alkaline medium, besides promoting intra cellular red pigments excretion, strongly represses citrinin synthesis.  相似文献   

15.
At any instant, the human erythrocyte sugar transporter presents at least one sugar export site but multiple sugar import sites. The present study asks whether the transporter also presents more than one sugar exit site. We approached this question by analysis of binding of [3H]cytochalasin B (an export conformer ligand) to the human erythrocyte sugar transporter and by analysis of cytochalasin B modulation of human red blood cell sugar uptake. Phloretin-inhibitable cytochalasin B binding to human red blood cells, to human red blood cell integral membrane proteins, and to purified human red blood cell glucose transport protein (GluT1) displays positive cooperativity at very low cytochalasin B levels. Cooperativity between sites and K(d(app)) for cytochalasin B binding are reduced in the presence of intracellular ATP. Red cell sugar uptake at subsaturating sugar levels is inhibited by high concentrations of cytochalasin B but is stimulated by lower (<20 nM) concentrations. Increasing concentrations of the e1 ligand forskolin also first stimulate then inhibit sugar uptake. Cytochalasin D (a cytochalasin B analogue that does not interact with GluT1) is without effect on sugar transport over the same concentration range. Cytochalasin B and ATP binding are synergistic. ATP (but not AMP) enhances [3H]cytochalasin B photoincorporation into GluT1 while cytochalasin B (but not cytochalasin D) enhances [gamma-32P]azidoATP photoincorporation into GluT1. We propose that the red blood cell glucose transporter is a cooperative tetramer of GluT1 proteins in which each protein presents a translocation pathway that alternates between uptake (e2) and export (e1) states but where, at any instant, two subunits must present uptake (e2) and two subunits must present exit (e1) states.  相似文献   

16.
从中国科学院微生物研究所保藏红曲菌中,筛选得到一株高产红色素的红曲菌菌株(AS.3.4617)。经鉴定属于红色红曲菌(Monascus anka Sato).通过有机溶剂的萃取和两次硅胶柱层析,从该菌株中分离得到两种色素样品,高压液相色谱测定为纯色素样品。通过元素组成分析,核磁共振谱,快离子轰击,质谱和高分辨质谱分析确定,这两种色素与已知的六种红曲菌色素不同,为新发现的红曲菌色素,它们可能的分子式为:C_(25)H_(31)O_5N和C_(23)H_(27)O_5N。  相似文献   

17.
1. The relative absorption spectrum of the pigments in their natural state in the photosynthetic bacterium Spirillum rubrum is given from 400 to 900 mµ. The position of the absorption maxima in the live bacteria due to each of the pigments is: green pigment, 420, 590, 880; red pigment, 490, 510, 550. 2. The relative absorption spectrum of the green pigment in methyl alcohol has been determined from 400 to 900 mµ. Bands at 410, 605, and 770 mµ were found. 3. The wave length sensitivity curve of the photosynthetic mechanism has been determined and shows maxima at 590 and about 900 mµ. 4. It is concluded that the green bacteriochlorophyll alone and not the red pigment can act as a light absorber for photochemical CO2 reduction.  相似文献   

18.
Brody , Marcia , and Robert Emerson . (U. Illinois, Urbana.) The effect of wavelength and intensity of light on the proportion of pigments in Porphyridium cruentum. Amer. Jour. Bot. 46(6): 433–440. Illus. 1959.—We specify a medium for Porphyridium cruentum made from distilled water and inorganic salts, without addition of earth extract, sea water or other supplements of uncertain composition, which sustains excellent growth through successive transfers. By control of intensity and wavelength of light used for growing the cultures, we have found it possible to vary the concentrations of chlorophyll and phycoerythrin, and also the proportions of these 2 pigments, over a considerable range. The changes in proportion of red and green pigments, in response to culturing in green and in blue light, are opposite to the changes that would be predicted from Engelmann's theory of complementary chromatic adaptation, when the intensities of the blue and green light are of the order of 104 ergs/cm2/sec. (or greater). However, at about 1/100 of this intensity, the changes are in the direction of complementary chromatic adaptation.  相似文献   

19.
Human erythrocyte hexose transfer is mediated by the glucose transport protein GLUT1 and is characterized by a complexity that is unexplained by available hypotheses for carrier-mediated sugar transport [Cloherty, E. K., Heard, K. S., and Carruthers, A. (1996) Biochemistry 35, 10411-10421]. The study presented here examines the possibility that the operational properties of GLUT1 are determined by host cell environment. A glucose transport-null strain of Saccharomyces cerevisiae (RE700A) was transfected with the p426 GPD yeast expression vector containing DNA encoding the wild-type human glucose transport protein (GLUT1), mutant GLUT1 (GLUT1(338)(-)(A3)), or carboxy-terminal hemagglutinin-polyHis-tagged GLUT1 (GLUT1-HA-H6). GLUT1 and GLUT1-HA-H6 are expressed at the yeast cell membrane and restore 2-deoxy-d-glucose, 3-O-methylglucose, and d-glucose transport capacity to RE700A. GLUT1-HA-H6 confers GLUT1-specific sugar transport characteristics to transfected RE700A, including inhibition by cytochalasin B and high-affinity transport of the nonmetabolized sugar 3-O-methylglucose. GLUT1(338)(-)(A3), a catalytically inactive GLUT1 mutant, is expressed but fails to restore RE700A sugar uptake capacity or growth on glucose. In contrast to transport in human red cells, K(m(app)) for 2-deoxy-d-glucose uptake equals K(i(app)) for 2-deoxy-d-glucose inhibition of 3-O-methylglucose uptake. Unlike transport in human red cells or transport in human embryonic kidney cells transfected with GLUT1-HA-H6, unidirectional sugar uptake in RE700A-GLUT1-HA-H6 is not inhibited by reductant and is not stimulated by intracellular sugar. Net uptake of subsaturating 3-O-methylglucose by RE700A-GLUT1-HA-H6 is a simple, first-order process. These findings support the hypothesis that red cell sugar transport complexity is host cell-specific.  相似文献   

20.
Beet hairy root cultures established from red and yellow varieties were grown in a 2 L bubble column reactor. The yellow clone showed profuse root hairs and a predominance of betaxanthin pigment with the red clone showed fewer root hairs and both betaxanthin and betacyanin pigments. The cultures displayed different ionic and sugar yields: 2.1 mg dry wt / mS.mL and 0.361 g dry wt / g sugar for the yellow clone and 2.3 mg dry wt / mS.mL and 0.375 g dry wt / g sugar for the red one. Both cultures grew at the same specific growth rate of 0.22 d-1in the bubble column, as compared to 0.32 d-1in shake flasks, indicating mass transfer limitations for growth in reactors.  相似文献   

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