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1.
The positional‐species composition (PSC) of 3‐acetyl‐1,2‐diacyl‐sn‐glycerols (AcDAGs) from the seeds of mature fruits of 14 species of the genus Euonymus L. was established. The residues of six major fatty acids (FAs), palmitic ( P ), stearic ( St ), hexadecenoic ( H ), octadecenoic ( O ), linoleic ( L ), and linolenic ( Ln ), were present in the AcDAGs. Here, we demonstrated that the profile of PSC of AcDAGs could serve as chemotaxonomic factor to divide euonymus species studied here into groups which completely correlate with the present day systematic of the genus. In particular, the Euonymus section greatly exceeded other sections of the Euonymus subgenus as well as the Kalonymus one in the total levels of AcDAGs positional species having one and two O residues and was characterized by significantly lesser concentrations of species with one and two L residues. Moreover, in seed, AcDAGs of almost all Euonymus species EFL values were slightly higher than EFO ones, but all EFL and EFO values were higher than 1.0, and therefore, it can be concluded that both FAs mainly esterified sn‐2‐position of the glycerol moiety and saturated FAs residues were always virtually absent in the sn‐2 position of Euonymus seed AcDAGs, as it is also the case in nearly all TAGs molecules of plant origin.  相似文献   

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Cerebroside was isolated from pea (Pisum sativum L.) seeds by solvent extraction, mild alkaline hydrolysis and silicic acid column chromatography. The purified material was identified as cerebroside by thin-layer chromatography and infrared spectrometry. Hydrolysates of the cerebroside were divided into fatty acid, sphingosine base and sugar fractions, and analysed, mainly by gas-liquid chromatography. The major fatty acid components were hydroxytricosanoic, hydroxydocosanoic and hydroxytetracosanoic acids. Dihydrosphingosine was the predominant sphingosine base. Only glucose was detected in the sugar fraction. Based on these results, one of the major species of pea cerebroside is suggested to be N-hydroxytricosanoyl-glucopyranosyl-dihydrosphingosine.  相似文献   

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A neuroactive substance was isolated in colorless crystalline state from body fluid of silkworm larvae which had been poisoned with DDT. It increased a spontaneous activity on the isolated abdominal nerve cord of American cockroaches, and resembled to the Sternburg’s unknwon neuroactive substance in some respects. This compound was, however, not aromatic amine but was identified as l-leucine by mass spectra, infrared absorption spectra, ultraviolet absorption spectra, and paper chromatography. Authentic l-leucine also showed a high neuroactivity.

Various kinds of other amino acids were also tested on the isolated nerve cord of cockroach, and they did not show any increase of spontaneous discharge except l-alanine, which appeared to have a weak neuroactivity.  相似文献   

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疣枝卫柔根皮中杀虫成分的分离及其生活性   总被引:5,自引:0,他引:5  
在生物活性追踪指导下,经液液分配萃取、中压柱层析及高效液相色谱制备,从柔科技植物疣枝枝卫柔(Euonymus verrucosides)根皮的甲醇提取物中,首次分离出一种对粘虫幼虫具有强烈麻醉活性的化合物,从其紫外光谱和红外光谱图中可以看出,该化合物具有二氢沉香呋喃骨架。  相似文献   

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Four isolectins (TEL-I, TEL-II, TEL-III and TEL-IV) were isolated from seeds of Talisia esculenta by reverse-phase high-performance liquid chromatography. RP-HPLC was performed on a u-Bondapack C18 column (0.78 cm × 30 cm) (Waters 991-PDA system) at room temperature. Rechromatography of the four fractions on a C18 column under the same conditions yielded lectins with two dissimilar subunits (Mr 20 kDa and 40 kDa) bound noncovalently. The isolectins showed very similar characteristics, such as molecular masses, N-terminal sequences, and hemagglutinating activity, but differed in their isoelectric points and in inhibition by carbohydrates.  相似文献   

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Oxidation of methyl trimethyl glucopyranosides which were obtained by methanolysis of permethylated cellulose, laminarin, and dextran, was performed with dimethyl sulfoxide (DMSO)-phosphorus pentoxide to afford the corresponding ulose derivatives, methyl 2,3,6-tri-O-methyl-d-xylo-hexopyranosid-4-ulose, methyl 2,4,6-tri-O-methyl-d-ribo-hexopyranosid-3-ulose, and methyl 2,3,4-tri-O-methyl-d-gluco-hexodialdo-l,5-pyranoside, respectively, in good or moderate yields. As a new type of derivatives for the linkage analysis of polysaccharides the chromatographic and spectrometric properties of 2,4-dinitrophenylhydrazone of the ulose derivatives were investigated.  相似文献   

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Vibrio parahaemolyticus, a causative bacterium of food poisoning unique for its particular primary association with sea products, is now divided serologically into 11 or 12 O-forms based on agglutination and agglutinin-absorption tests. We determined the sugar composition of the somatic O-antigens, i.e., lipopolysaccharides (LPS), of representative strains of each O-form. Of particular interest is the absence of evidence for the presence of 2-keto-3-deoxy-octonic acid (KDO), a regular sugar component of gram-negative bacterial LPS, in any LPS examined, with the exception of 06. Furthermore, 07 and 012 LPS contained a KDO-like compound that is, however, not identical with KDO. Glucose, glucosamine, and L-glycero-D-mannoheptose were found as common sugar constituents. Three unidentified amino sugars, designated here as P1, P2, and P3, were found. Various combinations of each of these unidentified amino sugars, and of galactose, fucose, arabinose, D-glycero-D-mannoheptose, galactosamine, KDO, and the KDO-like substance were detected in accordance with the O-form of LPS. On the basis of the sugar composition, LPS of the 12 O-forms of V. parahaemolyticus can be classified into nine chemotypes, because 03, 05, and 011 LPS belong to the same chemotype and 07 and 012 to another chemotype.  相似文献   

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利用不连续Percoll梯度分离得到高纯度的大豆(Glycine max)种子线粒体.线粒体制剂中没有检测到胞液、过氧化物体和叶绿素的污染.线粒体的完整性达到97%以上,在0~4℃下至少稳定2小时.  相似文献   

10.
花椒籽黑色素提取和脱蛋白技术研究   总被引:1,自引:0,他引:1  
李荣  贺学林  徐怀德 《西北植物学报》2008,28(12):2558-2563
采用二次回归正交旋转组合试验优化了花椒籽黑色素的浸提工艺,并用蛋白酶酶解-Sevag法联用脱除花椒籽黑色素中的蛋白.结果表明:影响花椒籽黑色素提取效果的因素依次为温度>NaOH浓度>料液比,花椒籽黑色素提取的优化工艺参数为NaOH浓度为1.20 mol/L,料液比为1∶24.64,温度为70℃下提取2 h,共2次,所得花椒籽色素粗品为棕黑色无定型粉末,得率为6.1%,色价为201.62,蛋白质含量为44.83%~48.63%.碱性蛋白酶脱蛋白条件为温度50℃,pH 9,加酶量为粗色素溶液(浓度为1 mg/mL)体积的6%,再用Sevag法处理3次,蛋白质脱除率可达81.23%,花椒籽黑色素色价可提高1.5倍.  相似文献   

11.
景新明  尹广鹍 《植物学报》2006,23(4):389-394
利用不连续Percoll梯度分离得到高纯度的大豆(Glycine max)种子线粒体。线粒体制剂中没有检测到胞液、过氧化物体和叶绿素的污染。线粒体的完整性达到97%以上, 在0~4 ℃下至少稳定2小时。  相似文献   

12.
The release from dormancy of Euonvmus europaeus L embryos bya brief treatment with GA3 has been studied During 48 h incubationof dormant embryos in GA-free medium, phospholipid levels increasedat first, then declined sharply over the last 6 h When the embryoswere placed in GA3 medium during this 6 h period levels of totalphospholipids as well as of phosphatidylethanolamine increasedwhilst phosphatidylinositol and phosphatidylcholine declinedslightly Fine structural changes stimulated by a brief GA3 treatmentwere of different character depending on tissue region (1) ‘destructive’changes occurred in the superficial procortical parenchyma onthe hypocotyl/radicle boundary, involving autolysis and decompartmentationof organelles, (2) ‘positive’ changes occurred inregions close to root and shoot apical meristems, involvingdegradation of protein bodies and their conversion into vacuoles,and the proliferation of various organelles A number of differenceswere noted when the changes in GA3-treated embryos were comparedwith those induced by low temperature, which also overcomesdormancy The results suggest that germination is accompaniedby different cytological events depending on whether it is inducedby cold or GA3 The growth of embryos in which dormancy was overcomeby GA3 was due to the activation of the apical root meristemclose to the quiescent centre, whilst in embryos in which germinationwas induced by low temperature, the periphery of hypotocotyl/radicleboundary was the site of activation Euonymus europaeus L, dormant embryo, fine structure, phospholipids, GA3 and cold treatments  相似文献   

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Charles Powell 《CMAJ》1940,43(4):372-373
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15.
Glucose and urea nitrogen determinations were made on blood and cerebrospinal fluid samples collected during 160 postmortem examinations in order to determine the usefulness of such tests in diagnosing diabetes and uremia at the time of autopsy. The results indicated that: (1) Blood is unsuitable for postmortem glucose determination, and no postmortem normal can be established. (2) Cerebrospinal fluid gave more uniform but very low glucose values. (3) Diabetics as a group had very high postmortem glucose levels but showed a marked overlap with non-diabetics. (4) Infants less than 3 months of age showed high postmortem glucose values. (5) Postmortem blood urea nitrogen and cerebrospinal fluid urea nitrogen levels were within normal limits in previously healthy persons who died suddenly from accidental causes. (6) Hospital autopsy cases had high urea nitrogen levels. (7) Postmortem urea nitrogen levels higher than 100 mg.% were indicative of uremia.  相似文献   

16.
本文对一株人抗人A-血型物质单克隆抗体,用定量免疫沉淀法以及ELISA研究其与多种单糖、双糖及寡糖的反应性,从而确定了其结合部位的结构特异性。实验发现其结合部位互补于含有双分子岩藻糖残基的A-t糖:这一研究进一步强调了含有双分子岩藻糖残基的A血型抗原决定簇的重要性。  相似文献   

17.
A deoxyribonuclease was purified about 500 times from a Rhizopus product “Gluczyme.” The enzyme attacks native DNA and produces oligonucleotides terminated with pG, pA, or pC at the 5′ end and with G at the 3′ end. A small amount of mononucleotides was found in the digestion products when the hydrolysis was continued for a long period. The pH and temperature optima for the action were found to be 7.8~8.0 and 50°C, respectively, and the enzyme was activated three fold in the presence of 5 × 10?3 m Mg2+ or Mn2+. This enzyme was named DNase Rh.  相似文献   

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