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1.
Extraction with hydrochloric acid (pH 2.5) of the brown alga Padina tetrastromatica afforded water-soluble and water-insoluble polysaccharides. The water-soluble polysaccharide was fractionated using cetyltritmethyl ammonium bromide and chromatography on DEAE-cellulose and Sephadex G-100. A neutral laminaran like glucan and two new sulphated heteropolysaccharides comprising d-glucuronic acid, l-fucose, l-rhamnose, d-xylose, d-arabinose, d-galactose, d-glucose and half-ester sulphate were obtained. The alginic acid isolated from this brown seaweed was found to be predominantly of poly 1 → 4β-d-mannuronic acid type. The water-soluble sulphated polymer showed high anticoagulant activity.  相似文献   

2.
Extraction with hydrochloric acid (pH 2.5) of the brown alga Padina pavonia afforded water-soluble and water-insoluble polysaccharides comprising D-glucuronic acid, L-fucose, D-xylose, D-mannose, D-glucose and D- galactose residues. The water-soluble polysaccharide was fractionated by using ethanol, and cetylpyridinium chloride and by chromatography on DEAE-cellulose. A neutral laminaran-like glucan, a sulphated heteropolysaccharide composed of the aforementioned sugars and a protein moiety were obtained. The isolated heteropolysaccharide showed high anticoagulation activity.  相似文献   

3.
A new sulphated heteropolysaccharide containing glucuronic acid, mannose, galactose, xylose, fucose and a protein moiety has been extracted from Sargassum linifolium. The polysaccharide extracted with HCl was richer in its carbohydrate and protein contents and contained lower amounts of ash than that extracted with oxalic acid.  相似文献   

4.
Rhizobium trifolii 11B was u.v. irradiated and nine u.v. mutants have been isolated. Among the mutants, only one, R. trifolii 21M11B, produced more (752 mg/100 ml) water-soluble polysaccharide than the parent (704 mg/100 ml). The composition of water-soluble polysaccharide from u.v. mutants differed from that of the parent, R. trifolii 11B, and none of its u.v. mutants produced water-insoluble polysaccharide as detected by the Aniline Blue method. Storage of u.v. mutants for 2 months at 5°C gave four spontaneous variants which acquired the ability to produce water-insoluble polysaccharide. The spontaneous mutants also retained their water-soluble polysaccharide producing ability. The water-soluble polysaccharide produced by these mutants was characterized as curdlan type. The chemistry of water-soluble and water-insoluble polysaccharides was also ascertained.  相似文献   

5.
Urospora wormskioldii and Codiolum pusillum are different life forms of this arctic alga. They both metabolise d-glucose, d-fructose, sucrose, myo-inositol, glyceric acid, and malto-oligosaccharides. In Codiolum, 1,3-linked d-glucose and l-rhamnose oligosaccharides were also present. The major polysaccharide extracted by water from both forms is a polydisperse, sulphated glucuronoxylorhamnan. Polysaccharides containing 1,3-, 1,4-, and triply linked d-glucose residues were also isolated from the aqueous extracts. Pure amylopectin-type polysaccharides were isolated from acid extracts of both forms of the weed. The major difference between the two forms was the presence in Codiolum of a sulphated (1→4)-linked β-d-mannan branched at C-6 and sulphated at C-2. The similarities and differences of the carbohydrates with those of Urospora penicilliformis and other green seaweeds are discussed.  相似文献   

6.
Several starter cultures used in the production of fermented beverages were screened for lactic acid bacteria that produced water-insoluble polysaccharides from sucrose. The strain producing the greatest amount was identified as Lactobacillus satsumensis by its 16S RNA sequence and was deposited in the ARS culture collection as NRRL B-59839. This strain produced at least two α-d-glucans from sucrose. One was a water-soluble dextran, consisting of predominantly α-(1?→?6)-linked d-glucose units, and the other was a water-insoluble glucan containing both α-(1?→?6)-linked and α-(1?→?3)-linked d-glucose units. The culture fluid was found to contain glucansucrases responsible for the two glucans, and no significant level of fructansucrase was detected. Glucansucrase activity was not present in the culture fluid when the bacteria were grown on glucose, fructose, or raffinose as the carbon source. Although the water-soluble glucans produced by cell-free enzyme and by cell suspensions were essentially identical, the same was not true for the water-insoluble glucans. The water-insoluble glucan produced by cell-free culture fluid contained a higher proportion of α-(1?→?3)-linked d-glucose units than the water-insoluble glucan produced by cell suspensions.  相似文献   

7.
Fucose-containing sulfated polysaccharides can be extracted from the brown seaweed, Sargassum sp. It has been reported that fucose-rich sulfated polysaccharides from brown seaweeds exert different beneficial biological activities including anti-inflammatory, anticoagulant, and anti-viral effects. Classical extraction of fucose-containing sulfated polysaccharides from brown seaweed species typically involves extended, multiple-step, hot acid, or CaCl2 treatments, each step lasting several hours. In this work, we systematically examined the influence of acid concentration (HCl), time, and temperature on the yield of fucose-containing sulfated polysaccharides (FCSPs) in statistically designed two-step and single-step multifactorial extraction experiments. All extraction factors had significant effects on the fucose-containing sulfated polysaccharides yield, with the temperature and time exerting positive effects, and the acid concentration having a negative effect. The model defined an optimized single-step FCSPs extraction procedure for Sargassum sp. (a brown seaweed). A maximal fucose-containing sulfated polysaccharides yield of ~7% of the Sargassum sp. dry matter was achieved by the optimal extraction procedure of: 0.03?M HCl, 90°C, 4?h. HPAEC-PAD analysis confirmed that fucose, galactose, and glucuronic acid were the major constituents of the polysaccharides obtained by the optimized method. Lower polysaccharide yield, but relatively higher fucose content was obtained with shorter extraction time. The data also revealed that classical multi-step extraction with acid ≥0.2?M HCl at elevated temperature and extended time had a detrimental effect on the FCSPs yield as this treatment apparently disrupted the structural integrity of the polymer and evidently caused degradation of the carbohydrate chains built up of fucose residues.  相似文献   

8.
During the growth ofAzotobacter vinelandii in batch culture in Burk's 2% glucose medium supplemented with 50mg EDTA per litre, water-insoluble capsular polysaccharide material accumulated in cultures prior to the appearance of water-soluble polysaccharide in the culture medium. On isolation, hydrolysis and chromatography, both these polysaccharides were observed to be composed of carbohydrate monomers having the same chromatographic mobilities as glucose, rhamnose, guluronic acid and mannuronic acid. The activity of GDP-d-mannose dehydrogenase recorded in crude cell-free extracts fromAzotobacter vinelandii, when these polysaccharides were produced, may indicate a close similarity between the biosynthetic pathway of alginate synthesis in marine Phaeophyceae and this soil microorganism.  相似文献   

9.
Three fractions of acidic water-soluble polysaccharides (concentration of glucuronic acid 10?C65%) were obtained from the above-ground part of St. Johns wort Hypericum perforatum L. by serial extraction with water and 0.7% aqueous solution of ammonium oxalate. Enzymatic hydrolysis of these polysaccharides using endo-polygalacturonase indicates that their carbohydrate chains contain the units of galacturone formed by 1,4-??-linked residues of non-substituted D-galacturonic acid. The extracted polysaccharides have been purified by means of gel filtration. It has been shown that water-soluble polysaccharides obtained by extraction with water manly contain the residues of galactose, mannose, glucose, and arabinose (the concentration of glucuronic acid being 10?C27%) while the polysaccharide fraction extracted using 0.7% aqueous solution of ammonium oxalate is presented by pectin polysaccharides. Only the residues of galacturonic acid (55?C72%) have been identified among glucuronic acids in its composition using chromatography/mass spectrometry of trimethylsilyl derivatives. In addition, this fraction contains the residues of the neutral monosaccharides which are typical for pectins: arabinoses, galactoses, rhamnoses, and glucose; there are also minor concentrations of residues of xylose and mannose. IR spectra of pectin polysaccharides of St. John??s wort have absorption bands in the ranges 1740, 1640?C1620, 1236?C1200, and 1200?C1000 cm?1 which are typical for pectins. It has been demonstrated that aqueous solutions of pectin polysaccharides of St. John??s wort (2 mg/mL) have pronounced antioxidant activity (44% of the activity of trolox taken for 100%).  相似文献   

10.
Microencapsulation of water-soluble drugs using coacervation-phase separation method is very challenging, as these drugs partitioned into the aqueous polymeric solution, resulting in poor drug entrapment. For evaluating the effect of ovalbumin on the microencapsulation of drugs with different solubility, pseudoephedrine HCl, verapamil HCl, propranolol HCl, paracetamol, and curcuminoid were used. In addition, drug mixtures comprising of paracetamol and pseudoephedrine HCl were also studied. The morphology, encapsulation efficiency, particle size, and in vitro release profile were investigated. The results showed that the solubility of the drug determined the ratio of ovalbumin to be used for successful microencapsulation. The optimum ratios of drug, ovalbumin, and gelatin for water-soluble (pseudoephedrine HCl, verapamil HCl, and propranolol HCl), sparingly water-soluble (paracetamol), and water-insoluble (curcuminoid) drugs were found to be 1:1:2, 2:3:5, and 1:3:4. As for the drug mixture, the optimum ratio of drug, ovalbumin, and gelatin was 2:3:5. Encapsulated particles prepared at the optimum ratios showed high yield, drug loading, entrapment efficiency, and sustained release profiles. The solubility of drug affected the particle size of the encapsulated particle. Highly soluble drugs resulted in smaller particle size. In conclusion, addition of ovalbumin circumvented the partitioning effect, leading to the successful microencapsulation of water-soluble drugs.  相似文献   

11.
The data are presented concerning the amount of mobile compounds of chemical elements (ChE) in soils under various human impact (acetate-ammonium buffer at pH 4.8) and in plants of ripple-seed plantain (Plantago major L.) (extractants such as diluted 1:1 HCl, 10% HCl, distilled H2O). The content of total ash, mineral impurities of soil origin, water-soluble forms of ChE, polysaccharides and chlorophyll was determined in plants. The obtained data were compared with those for other regions. The ecological state of Plantago major L. was estimated and a conclusion was drawn about its possible use as a medicinal raw material.  相似文献   

12.
Sulfuric acid hydrolysis according to the Saeman procedure, TFA hydrolysis, and methanolysis combined with TFA hydrolysis were compared for the hydrolysis of water-soluble uronic acid-containing polysaccharides originating from fungi, plants, and animals. The constituent sugar residues released were subsequently analyzed by either conventional GLC analysis of alditol acetates or high-performance anion-exchange chromatography with pulsed-amperometric detection. It was shown that TFA hydrolysis alone is not sufficient for complete hydrolysis. Sulfuric acid hydrolysis of these polysaccharides resulted in low recoveries of 6-deoxy-sugar residues. Best results were obtained by methanolysis combined with TFA hydrolysis. Methanolysis with 2 M HCl prior to TFA hydrolysis resulted in complete liberation of monosaccharides from pectic material and from most fungal and animal polysaccharides tested. Any incomplete hydrolysis could be assessed easily by HPAEC, by the detection of characteristic oligomeric products, which is difficult using alternative methods currently in use. Methanolysis followed by TFA hydrolysis of 20 micrograms water-soluble uronic acid containing polysaccharides and subsequent analysis of the liberated sugar residues by HPAEC allowed us to determine the carbohydrate composition of these polysaccharides rapidly and accurately in one assay without the need for derivatization.  相似文献   

13.
Cyclosporine A (CsA) has been universally used as an immunosuppressant for the management of organ transplantation and various autoimmune diseases. However, nephrotoxicity due to CsA remains to be an important clinical challenge. In the present investigation, an attempt has been made to appraise the effect of sulphated polysaccharides on oxidative renal injury caused by CsA. Adult male Wistar rats were divided into four groups. Two groups received CsA by oral gavage (25 mg/kg body weight) for 21 days to provoke nephrotoxicity, one of which simultaneously received sulphated polysaccharides subcutaneously, (5 mg/kg body weight). A vehicle (olive oil) treated control group and sulphated polysaccharides drug control were also built-in. An increase in lipid peroxidation along with abnormal levels of enzymic (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione-S-transferase and glucose-6-phosphate dehydrogenase) and non-enzymic antioxidants (glutathione, vitamin C and vitamin E) are the salient features observed in CsA induced nephrotoxicity. CsA induced impairment of renal toxicity was evident from the marked decline in the activities of renal marker enzymes like alkaline phosphatase, acid phosphatase and lactate dehydrogenase, as well as an apparent increase in the serum urea, uric acid and creatinine; diagnostic of renal damage was normalized by sulphated polysaccharides co-administration. Sulphated polysaccharides treatment showed an effectual role in counteracting the free radical toxicity by bringing about a significant decrease in peroxidative levels and increase in antioxidant status. These observations emphasize the antioxidant property of sulphated polysaccharides and its cytoprotective action against CsA induced nephrotoxicity.  相似文献   

14.
Isolation of water-soluble alginate from brown algae   总被引:2,自引:1,他引:1  
Nishide  E.  Tsukayarna  K.  Uchida  N.  Nisizawa  K. 《Hydrobiologia》1984,116(1):557-562
Summary Water-soluble alginate was obtained from an aqueous extract of Kjellmaniella crassifolia by precipitation with HCl, calcium acetate or 20% ethanol in the presence of 0.05 M MgCl2 Of these precipitation procedures, MgCl2-ethanol gave the purest alginate preparation as judged by electrophoresis. The thin-layer and gas-liquid chromatography of its acid hydrolysate, and the IR spectra analysis of the whole alginate, suggested that the water-soluble alginate is similar to ordinary water-insoluble and alkali-soluble alginate such as Kelco alginate.However, the alginate obtained in the present work contained a great excess of mannuronic acid residues, giving an M:G ratio of about 13. Its molecular weight distribution was rather broad as with Kelco alginate, but the molecular weight of its major component was estimated to be 500 000 amu, whereas that Kelco alginate measured on the same column under the same condition was 1 700 000 amu. This suggests that water-soluble alginate was far smaller in average molecular size than Kelco alginate.  相似文献   

15.
Wang  Y. Q.  Sun  J. X.  Guo  F. Q.  Zhang  Z. Y  Chen  H. M.  Xu  L.  Cao  G. Y. 《Biological trace element research》1999,(1):103-108
The binding of rare earth elements (REEs) with water-soluble polysaccharides of nondeproteinization and deproteinization in the leaves of the fernDicranopteris dichotoma was studied by molecular activation analysis (MAA). Two cold-water-soluble polysaccharides (extracted by 75% ethanol and 90% ethanol, respectively) and one hot-water-soluble polysaccharide (extracted by 90% ethanol) were separated using biochemical separation techniques. The eight rare earth elements (La, Ce, Nd, Sm, Eu, Tb, Yb, and Lu) in these polysaccharides were determined by instrumental neutron activation analysis. Our new results showed that the REEs were bound firmly with the water-soluble polysaccharides in the plant, regardless of whether nondeproteinization or deproteinization was used. The molecular-weight (MW) measurement demonstrated that REEs were mainly bound with low-MW (10,000–20,000) polysaccharides.  相似文献   

16.
The anticoagulant activities of sulphated alginic acids, amylose, cellulose, chitosan, curdlan, dextran, guaran, laminaran and locust bean gum have been studied. The alginic acids have been partially reduced and some of the neutral polysaccharides have been partially oxidised at C-6 of the glycopyranosyl residues. The activities of sulphated polymers containing different proportions of uronic acid and neutral sugar residues have been compared.The results suggest that polysaccharides with an average of at least one sulphate group on each monomeric unit, a molecular weight higher than 10 000 and a high proportion of sulphated primary hydroxyl functions will display activity in the activated, partial thromboplastin time assay (APTT). Sulphated guaran and locust bean gum had the highest activities of the polymers investigated (70 IU/mg, heparin has 130-50 IU/mg). In the concentration range investigated, none of the sulphated polymers showed any significant activity in an anti-factor Xa assay.  相似文献   

17.
Pectins were extracted either by water from extruded lemon fibre or by hot acid from the raw lemon fibre. The amount of water-soluble polysaccharides from lemon plant cell walls was greatly increased after extrusion-cooking. The pectins obtained by extraction with water from the extruded fibre and the pectins extracted from the raw material by hot acid were studied. The water-soluble pectins obtained after extrusion-cooking had the distinctive feature of being very highly (92%) methylated; they were also particularly rich in arabinose side-chains. High molecular weight material coming from the “hairy” regions was isolated after digestion by an endo-polygalacturonase. Methylation analysis revealed the presence in both pectins of fairly branched (1 → 5)-linked arabinans and arabinogalactans of type I and II side-chains.  相似文献   

18.
Analytical data are presented for the water-soluble gum exudates from Brachystegia glaucescens, B. spiciformis, and Julbernardia globiflora. They are acidic polysaccharides containing glucuronic acid, 4-O-methylglucuronic acid and galacturonic acid, together with galactose, minor amounts of arabinose, and relatively high proportions of rhamnose. The exudate from B. glaucescens is of particular interest in having high molecular weight, high intrinsic viscosity, and a high methoxyl content. The nitrogen content of all three gums is low, but amino acid analysis shows that proteinaceous components are involved, as in the gum exudates from other genera.  相似文献   

19.
A systematic method of extraction, fractionation, and purification of polysaccharides from Songshan Lingzhi (Ganoderma tsugae) with antitumor activity was established.

Seven glycans with strong antitumor activities were obtained from 14 water-soluble, and 15 water-insoluble fractions: FIo-a, FA-1, FII-1, FIII-2, and FIII-2-a, -b, and -c. FIo-a and FA-1 were proteincontaining glucogalactans associated with mannose and fucose. FII-l was a (1→3)-β-D-glucan having a lower protein content. The water-insoluble fractions FIII-2-a, -b, and -c were extracted with alkali, and were found to be protein-containing (1→3)-β-D-glucans showing the strongest activity. Chemical properties .and structure of each antitumor polysaccharide were compared with three fungi of the Ganoderma family, Kofukitake (G. applanatum), Mannentake (G. lucidum), and Songshan Lingzhi (G. tsugae).  相似文献   

20.
Summary A complex, higly sulphated glucoxylomannogalactan has been extracted in a yield of about 1% dry weight fromC. simpliciuscula. This polysaccharide is similar in composition to sulphated polysaccharides previously isolated from otherCaulerpa species (Mackie andPercival, 1961). The most likely location of this compound in the unwounded cell is in the vacuole. This polysaccharide appears as the major component in wound plugs, forming a viscoelastic barrier between the protoplasm and the external environment. The properties of the sulphated polysaccharide were studied in an effort to understand the physiology and mechanism of wound plug formation.  相似文献   

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