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1.
Galactomannan, a heteropolysaccharide with a molecular weight of 1660 kDa, was isolated form the seed of Gleditsia ferox Desf., introduced in Russia, with a yield of 18.9%. Its aqueous solutions were optically active ([alpha]D = +30.5 degrees) and highly viscous ([eta] = 1430 ml/g). Analysis of the heteropolysaccharide using chemical, enzymatic, and chromatographic procedures showed that it consists of D-mannopyranose and D-galactopyranose residues (molar ratio, 2.54:1). The main chain of this galactomannan consists of 1,4-beta-D-mannopyranose residues, 39.2% of which are substituted at C6 with single residues of alpha-D-galactopyranose. The probability of occurrence of mannobiose units differentially substituted with galactose was determined by 13C-NMR data and equaled, respectively, 0.37, 0.47, and 0.16 for non-substituted Man-Man units, monosubstituted Gal(Man-Man) and (Man-Man)Gal units taken together, and for the disubstituted Gal(Man-Man)Gal units.  相似文献   

2.
Galactomannan, a polysaccharide with a molecular weight of 660 kDa, was isolated for the first time from the seed of Gleditsia triacanthos f. inermis (yield, 15.4%). Its aqueous solutions were optically active ([] D = +31.0°) and highly viscous ([] = 578 ml/g). Analysis of this heteropolysaccharide using chemical, enzymatic, and chromatographic procedures, as well as IR and 13C NMR spectroscopy, showed that it consists of D-mannopyranose and D-galactopyranose residues (molar ratio, 2.42 : 1). The main chain of this galactomannan comprises 1,4--D-mannopyranose residues, 41% of which are substituted at C6 with single residues of -D-galactopyranose. The probability of occurrence in the chain of mannobiose units substituted otherwise, determined experimentally, was 0.16 for the Man–Man unit, 0.50 for the Gal(Man–Man) and (Man–Man)Gal units, and 0.34 for the disubstituted Gal(Man–Man)Gal unit.  相似文献   

3.
使用不同浓度乙醇和异丙醇分别对皂荚半乳甘露聚糖胶水溶液进行分级沉降,沉淀物用凝胶渗透色谱(GPC)和高效液相色谱(HPLC)等进行表征.结果表明,异丙醇可在较小浓度下更快沉降皂荚多糖胶,当异丙醇溶液浓度为28.6% (V/V)时,沉淀物中半乳甘露聚糖浓度达到12.50%(w/w);随着醇浓度上升,沉降组分半乳甘露聚糖得率呈增加趋势,且在后期增加幅度最大,多糖最高得率可达80%,纯化后皂荚多糖胶(GSG)表现出较高的甘露糖/半乳糖(M/G)之比值,在异丙醇沉降中表现更加明显(低浓度的异丙醇达到最高的M/G =4.1);低浓度醇沉主要得到大分子组分,随乙醇浓度增加组分分子量明显降低,多糖胶更加均匀,而在异丙醇沉降后期均一性有所下降.  相似文献   

4.
By the hot water extraction method, galactomannan was extracted (4.5% yield of the seed mass) from the seeds of Chinese honey locust (Gleditsia sinensis Lam). It had a molecular weight of 1230 kDa, and its solutions had a high viscosity [η] of 1064 ml/g and optical activity [α]D of +21.4°. The polysaccharide consists of mannose and galactose residues in the molar ratio 2.69: 1. In the galactomannan macromolecule the backbone is formed by 1,4-β-D-mannopyranose residues, 37% of which are substituted by α-D-galactopyranose at C6. By 13C-NMR-spectroscopy, fragments of differently galactose-substituted mannobiose units were found to be in the galactomannan being studied: Man-Man, (Gal)Man-Man, and Man-Man(Gal) in the ratio of 0.23: 0.47: 0.30.  相似文献   

5.
It is determined that the gum from the endosperm of Gleditsia sinensis Lam. consists of D-galactose and D-mannose in the proportions of 1:(3.9–4.0) and the chemical structure is in the form of the gums from two other plants G. melanacantha Tang et Wang and G. heterophylla Bunge were determined also and their chemical structures are in the form of  相似文献   

6.
Galactomannan, a water-soluble heteropolysaccharide, was isolated from the seed of a Far Eastern population of the ground honeysuckle Lotus corniculatus L. (yield, 1.65%). Analysis of this galactomannan showed that it consists of D-mannose and D-galactose residues (molar ratio, 1.22 : 1). Its aqueous solutions were characterized by a specific rotation []D= +84.1° and intrinsic viscosity [] = 559 ml/g. Analysis of this heteropolysaccharide using chemical and enzymatic procedures, as well as IR and 13C NMR spectroscopy, showed that its main chain comprises 1,4--D-mannopyranose residues, 95.5% of which are substituted at C-6 with single residues of -D-galactopyranose.  相似文献   

7.
Mature seed coats of representatives of all three genera ofMusaceae were analysed for macromolecular composition with variousmass spectrometric techniques and compared with scanning electronmicroscopy and light microscopy in combination with histochemicaltechniques. Mass spectrometric techniques are more sensitiveand more specific in identifying macromolecular compounds thanhistochemical methods. The macromolecular ‘fingerprint’of the seed coats of Musaceae showed unique components of aromaticphenols. The seed coat structure of all three genera is homogeneouswithin the Musaceae. It is characteristic at the family leveland most complex within the Zingiberales. Very remarkable arethe separation of the outer cell walls from the exotestal layer,exposing a secondary surface with silica crystals, and the relativelythick mesotesta which protects the seed, e.g. against the bitingforces and passage through the digestive tracts of dispersingagents. Germination takes place with an operculum and is facilitatedby a predetermined rupture layer in the micropylar collar. Themusaceaous seed presents a good example of the solution of conflictingdemands of protection and germination. Musaceae; Musa; Ensete; Musella; seed coat; pyrolysis (gas chromatography) mass spectrometry; histochemistry; anatomy; macromolecules; silica; lignin; cellulose; vegetable polyphenols; operculum; germination  相似文献   

8.
The endosperm of the seed of Gleditsia triacanthos L. contains 18.55% of its dry weight as nonreserve, cell-wall carbohydrates. Of this carbohydrate material, comprising mainly mannose, galactose, and glucose, 76.1% was of low-molecular weight or highly hydrophilic. Mannose, galactose, and glucose were also the major sugar components of the polysaccharides extracted with alkali (23.1% of the cell-wall), while the same sugars, with minor amounts of arabinose, form the residues. Methylation analysis of the polysaccharides and the borate-sodium hydroxide residue indicate that the cell walls are built up on a network of galactomannans, with high Man/Gal ratios, reinforced with minor amounts of cellulose.  相似文献   

9.
Aiming of self-sustainable production, the search for biodegradable and biocompatible materials has brought with it the need to know the physicochemical and dielectric characteristics of polysaccharide-based composite structures, which can be used as important and promising raw materials for biotechnology and electronic industries. Galactomannans are polysaccharides, extracted from seeds and microbiological sources, consisting of mannose and galactose. In this context, this work aimed to extract, purify and characterize by XRD, FTIR and impedance spectroscopy galactomannan obtained from seeds of Adenanthera pavonina L. The purification process was made with ethyl alcohol at concentrations of 70, 80 and 90 %. Polymeric films were prepared by solvent slow evaporation at low temperatures. XRD measurements revealed that Galactomannan from Adenanthera pavonina L., after purification, has a semi-crystalline structure due to the identification of two peaks the first between 5.849° and 6.118° and the second between 20.011° and 20.247°. FTIR spectra showed the functional groups associated with monosaccharides of the galactomannan from Adenanthera pavonina L. seeds, as well as the typical polysaccharide bands and peaks, confirmed by literature data. The impedance results give an increment on the state-of-the-art of this biomaterial by showing the existence of dielectric relaxations, independent of the degree of purification, using the dielectric modulus formalism. The permittivity analysis reveals the presence of water in the structure of the film, whose dipoles contribute to the relatively high value of the dielectric constant. From the results obtained, it can be concluded that purified galactomannan has the potential for possible applications in the electronics industry as a green and eco-friendly dielectric material.  相似文献   

10.
Two fractions (1 and 2) of the galactomannan from seeds of sophora (Styphnolobium japonicum) were isolated using cold and hot aqueous extraction with a total yield of 12.88%. The two fractions differed by the ratio between mannose (Man) and galactose (Gal) residues (4.8 : 1 and 5.3 : 1, respectively) and molecular weight (1190 and 1400 kDa, respectively). Aqueous solutions of these fractions were optically active ([]D = +4.80° and –3.36°, respectively) and highly viscous ([] 1028.8 and 1211.2 ml/g). 13C NMR spectra of both fractions were identical with respect to the number and positions of signals, which indicates that their primary structures were identical. Using chemical and spectroscopic (IR and NMR) methods, it was shown that the galactomannan has a main chain consisting of 1,4--D-mannopyranose, some residues of which (16 and 17% in fractions 1 and 2, respectively) are -galactosylated at the C-6 position. Frequencies of differently substituted mannobiose blocks in the chain, calculated for fraction 1 using NMR spectroscopic data, were 0.13 for the disubstitited blocks Gal(Man–Man)Gal, 0.37 for the sum of monosubstituted blocks Gal(Man–Man) and (Man–Man)Gal, and 0.50 for the unsubstituted block Man–Man.  相似文献   

11.
12.
采用正交试验方法研究了超临界CO_2萃取石榴(Punica granatum L)籽油的技术体系,并用气相色谱-质谱联用仪对石榴籽油的化学成分进行了分析。结果表明,超临界CO_2萃取石榴籽油的最佳工艺条件为:萃取压力25 MPa,萃取温度30℃,分离温度55℃,萃取时间70min,在此条件下油脂产率为20.4%。GC-MS分析的结果显示,石榴籽油的主要成分是脂肪酸。饱和脂肪酸以棕榈酸为主,不饱和脂肪酸主要是亚麻酸和亚油酸,占脂肪酸总量的86.86%。  相似文献   

13.
不同产地长柄扁桃种仁成分分析   总被引:2,自引:0,他引:2  
采用GC-MS、AAS、HPLC等方法对选自陕西神木、内蒙古包头、内蒙古阿拉善盟、河北承德4个不同产地的长柄扁桃种仁的一般成分(粗脂肪、粗蛋白、水分、灰分、总糖、总膳食纤维)、氨基酸、微量元素、脂肪酸及苦杏仁苷含量等进行分析。研究表明,不同产地长柄扁桃种仁各组分含量有一定差别,但均富含粗脂肪(416~478g/kg)和粗蛋白(206~286g/kg);种仁中氨基酸种类齐全,含量丰富;均含Ca、Mg、P、Fe、K等9种对人体有益的矿质元素,未检出Pb、Cd、Hg、As等元素;长柄扁桃油中不饱和脂肪酸含量在96.8%以上,以油酸和亚油酸主;苦杏仁苷含量在3%左右。从测定结果来看,长柄扁桃种仁可以作为开发食用油、蛋白粉以及苦杏仁苷的原材料,具有较好的经济价值,适宜于广大北方荒漠地区推广种植。  相似文献   

14.
Three new sulfated isoguanine alkaloid glycosides, designated as saikachinoside A monosulfate ( 1 ), saikachinoside A disulfate ( 2 ), and locustoside B disulfate ( 3 ), have been isolated from the pupal case of the wild bruchid seed beetle Bruchidius dorsalis (Chrysomelidae, Bruchinae) infesting the seed of Gleditsia japonica Miq . (Fabaceae). Their structures were determined by spectroscopic methods and the inhibitory activity of 2 and 3 against acid phosphatase was evaluated.  相似文献   

15.
小鱼仙草种子化学成分的研究   总被引:1,自引:1,他引:1  
对小鱼仙草种子的化学成分进行研究,结果表明:种子脂肪油含量为20.26%,其主要成分为:亚油酸(15.117%)、亚麻酸(67.356%)、油酸(11.349%)、棕榈酸(4.988%)、硬脂酸(11.80%)等,种子油含有大量人体所需的不饱和脂肪酸。此外还测定了种子的17种氨基酸和24种矿质元素。其种子和种子油具有较高的营养价值和医疗保健功效,具有潜在开发利用的价值。  相似文献   

16.
Four new long-chain esters of trans-ferulic acid (14) were isolated from the thorns of Gleditsia sinensis, together with eight known compounds (513). The structure elucidations were achieved by in-depth spectroscopic examination, mainly including multiple 1D- and 2D-NMR and HRESIMS experiments and analyses. Cytotoxic activities of these compounds were evaluated against human liver cancer SK-hep-1 cell line by the MTT in vitro assay. Among them, compound 13 exhibited potent cytotoxic activity with IC50 value of 38.18 μM, and compounds 7 and 8 showed moderate cytotoxic activities with IC50 values of 58.11 and 54.61 μM, respectively.  相似文献   

17.
Mayor, Heather D. (Baylor University College of Medicine, Houston, Tex.), Richard M. Jamison, Liane E. Jordan, and Joseph L. Melnick. Structure and composition of a small particle prepared from a simian adenovirus. J. Bacteriol. 90:235-242. 1965.-When tissue-culture fluids infected with simian adenovirus SV15 are examined in an electron microscope, either as fresh harvests or after treatment with Genetron, typical mature adenovirus particles are found. These are 65 to 70 mmu in diameter, with an icosahedral capsid built from 252 capsomeres. Also present is a population of small polyhedral particles approximately 20 mmu in diameter. These small particles can be separated from the mature virions by ultrafiltration or density gradient centrifugation. The small particles have a density of 1.43 in cesium chloride. They contain protein and double-stranded deoxyribonucleic acid. They appear to possess cubic symmetry of the icosahedral type, with a coat composed of 12 subunits each at the vertex of an icosahedron.  相似文献   

18.
Abstract

The relative concentration and distribution of nickel (Ni) in vegetative tissues (leaves, stems and trichomes) and reproductive organs (seeds) was studied using energy-dispersive X-ray microanalysis (EDXS) and scanning electron microscopy (SEM) in two previously studied Ni-hyperaccumulator subspecies of Alyssum serpyllifolium Desf. growing naturally in ultramafic soils of the Iberian Peninsula: A. serpyllifolium ssp. lusitanicum Dudley & P. Silva and A. serpyllifolium ssp. malacitanum Rivas Goday ex G. López. Both taxa showed that Ni accumulates preferentially in the leaves, exhibiting a homogeneous distribution on both epidermis surfaces. The highest Ni concentrations were found inside the epidermal cells and at the base of trichome stalks. Ni accumulation in seeds was lower than in the vegetative organs. The location of Ni in these plants allows us to postulate that its accumulation is a protection mechanism against external stress.  相似文献   

19.
20.
皂荚中一种杀鼠活性成分的分离鉴定   总被引:1,自引:0,他引:1  
采用70%乙醇渗漉提取,正丁醇萃取,常压硅胶柱反复层析,结合杀鼠活性追踪的方法,从豆科植物皂荚(Gleditsia sinensis Lam.)的果实中分离到一个含有7个糖基的三萜皂苷,通过TLC、mp、IR、MS、1H-NMR和13C-NMR等方法鉴定为3-O-β-D-吡喃木糖基-(1→2)-α-L-吡喃阿拉伯糖基-(1→6)-β-D-吡喃葡萄糖基齐墩果酸28-O-β-D-吡喃木糖基-(1→3)-β-D-吡喃木糖基-(1→4)-α-L-吡喃鼠李糖基-(1→2)-[(6S,2E)-6-羟基-2,6-二甲基-2,7-辛二烯醇-(1→6)]-β-D-吡南葡萄糖酯;对小鼠的毒性测定表明,试鼠经口灌胃的耐受量为200~800 mg/kg,LD50为508.31 mg/kg,95%可信区间为449.40~574.95 mg/kg.该三萜皂苷为皂荚杀鼠的活性成分.  相似文献   

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