Kinds Of Polysaccharides Research Articles

ラジカル反応による多糖の酸化と解重合

The studies on the radical oxidation and depolymerization of polysaccharides in biological tissues and food stuffs published in recent years are reviewed and summarized. The radical reactions of polysaccharides taken up in here are initiated by the ionizing radiation and the action of active oxygen species, i.e. superoxide anion radical, hydrogen peroxide and hydroxyl radical. (1) Starch radicals formed in radiolysis transferred to soluble dextrins and low molecular carbonyl compounds through their radical rearrangements. These products decreased markedly with increase of moisture content in starch. Radiolysis mechanism has been proposed as shown in Schemes. (2) The active oxygen radicals from some oxidase systems and ascorbic acid-metal ion system depolymerize many kinds of polysaccharides, i.e. hyaluronate, pectin, starch and etc. These depolymerizations were inhibited by the addition of SOD, catalase and some hydroxyl radical scavengers, and a main principle in radical species has been estimated as hydroxyl radical. These interactions seemed to be associated with the biodeterioration in biological bodies and food stuffs.

9?-Hydroxylation of 4-androstene-3,17-dione by gel-entrapped Corynebacterium sp. cells

Whole cells of Corynebacterium sp. having steroid 9α-hydroxylation system were immobilized by entrapment with photo-crosslinkable resin prepolymers, urethane prepolymers or several kinds of polysaccharides. Of various entrapment methods tested, cells entrapped in photo-crosslinked gels showed the highest activity to hydroxylate 4-androstene-3,17-dione at 9α-position. The properties of the photo-crosslinkable resin prepolymers, such as the hydrophobicity and the chain length of the prepolymers, affected markedly the activity of the entrapped cells. Addition of dimethyl sulfoxide to a buffer system at 15 vol. % was effective to solubilize the product, 9α-hydroxy-4-androstene-3,17-dione, and gave the highest yield. In an aqueous system, the activity of hydrophilic gel-entrapped cells was higher than that of hydrophobic gel-entrapped cells. In 15% of dimethyl sulfoxide, the hydrophobic gel-entrapped cells showed almost the same activity as the hydrophilic gel-entrapped cells probably due to extraction of the product from gels to the external solvent before its metabolic degradation. Entrapment significantly enhanced the conversion ratio at high substrate concentrations and the operational stability of the 9α-hydroxylation system in the cells. In the presence of nutrients in the reaction mixture, entrapped growing cells maintained fully the original activity at least during 10 times of repeated batch reactions for 5 days.

Relationship between biochemical and cytochemical results obtained on Bacillus megaterium and Bacillus subtilis cell-wall polysaccharides

Two different polysaccharide stains, phosphotungstic acid (PTA) and silver proteinate (SP), were applied to isolated walls of Bacillus subtilis 168 and B. megaterium MA and MB. To get a better insight into their staining specificity for the cell-wall polymers, these procedures were carried out after extraction of nonpeptidoglycan polymers or after peptidoglycan degradation. It appeared that in the bacterial cell wall, PTA stains peptidoglycan and SP stains nonpeptidoglycan polymers. In B. subtilis the SP-positive polymer is teichoic acid, in B. megaterium MB another kind of polysaccharide; in strain MA teichoic acid and another polysaccharide were probably responsible for the SP reaction. A partial analysis of the cell-wall sugar and phosphorus content confirmed these findings. The nature of the anionic sites present in the cell wall was also investigated by using cationized ferritin.

11?-Hydroxylation of progesterone by gel-entrapped living Rhizopus stolonifer mycelia

Spores of Rhizopus stolonifer were immobilized aseptically by entrapment with photo-crosslinkable resin prepolymers, urethane prepolymers or several kinds of polysaccharides. The entrapped spores were allowed to germinate and develop in situ. The immobilized living mycelia so obtained were induced for the steroid 11α-hydroxylation system and examined for their activity to hydroxylate progesterone at 11α-position in a buffer system containing 2.5% of organic cosolvent. Of various water-miscible organic cosolvents, methanol was found to be most effective in terms of the activity of the entrapped mycelia and the solubility of the product, 11α-hydroxyprogesterone. Though all the living mycelia entrapped in different gels exhibited the hydroxylation activity, mycelia entrapped in photo-crosslinked gels showed the maximum activity which was rather higher than that of the free mycelia. The net-work size of the photo-crosslinked resins, namely the chain length of the photo-crosslinkable resin prepolymers, affected markedly the mycelial growth in gels, and subsequently, the hydroxylation activity of the entrapped mycelia. Entrapment significantly enhanced the operational activity and stability of the 11α-hydroxylation system in the mycelia, and permitted the intermittent reactivation of the system by incubating the entrapped mycelia in potato-dextrose broth.

Kinetic study on the effects of acidic polysaccharides on the interaction of fibrinogen and thrombin

Retardation effect of acidic polysaccharides on the interactions of fibrinogen with thrombin was kinetically investigated by measuring the turbidity as a measure of the concentration of fibrin polymer formed in the system. To this aim, the fibrinogenfibrin conversion curve was analyzed kinetically based on the elementary reactions, and the slope and the induction period of the conversion curve were expressed as functions of the concentrations of fibrinogen, thrombin, and polysaccharide. The strong retardation effect of dextran sulfate and heparin was quantitatively interpreted. Seven kinds of polysaccharides were examined.

Antitumor Activities of Marine Algae Constituents

Recently immunotherapy has been considered to be an important method to increase immunopotentiating activity of host in the treatment of neoplastic diseases. In the therapy, polysaccharides have attracted attention because of their activity to enhance host defense mechanisms against neolpastic diseases. Some kinds of polysaccharides have been fouud to provide immunopotentiating activity which brought about regression of tumors and helped protect against infectious diseases.In this study, screening tests were conducted for several years for the selection of suitable polysaccharides for clinical trials, and several marine algae containing polysaccharides with immunopotentiating activity were found. Immunostimulant substances, which were collected from brown algae, Sargassum fulvellum C. Agardh, Sargassum thunbergii O. Kuntze and Eisenia bicyclis Setchell, markedly potentiated host antitumor activity which was proved by regression and elimination of the tumor.

TYPE IV GLYCOGENOSIS ‐ A STUDY OF TWO CASES

Liver biopsy materials of two siblings with type IV glycogenosis were studied by light and electron microscopy. Biochemical analysis was added using autopsy material in one of the two cases. Two kinds of polysaccharides were noted not only in the cardiac muscle, skeletal muscles, smooth muscles and reticuloendothelial cells, but also in the neutrophils and platelets. One was glycogen and the other was similar to amylopectin. Ultrastructurally, a large amount of fibrils, 60 A in width, glycogen rosettes and glycogen granules were detected in those cells. Branching glycosyltransferase deficiency was biochemically confirmed in one case examined.

Structure of cell wall and exocellular mannans from the yeast Hansenula holstii: I. Mannans produced in phosphate-containing medium

1. 1. Cell wall mannan and exocellular phosphomanna from Hansenula holstii NCYC 560 were analysed to determine their structures. 2. 2. Both preparations were composed of a mixture of several polysaccharides (molecular weight = 1. 10 6) differing in degree of phosphorylation and in structural arrangement. 3. 3. The cell wall mannan was a mixture of two branched polysaccharides containing 1,2- and 1,3-linkages, one of the fractions having β-linkages in addition to the α-linkages usually found in these polymers. 4. 4. The exocellular phosphomannan was composed of three polymers, all of them with an α-1,6-linked backbone to which α-1,2- and α-1,3-linked side chains of various lengths were attached. 5. 5. The cell wall mannan contained phosphodiester linkages as reported for mannans from other species. However, the highly phosphorylated exocellular mannan was a novel kind of polysaccharide having its phosphates in the monoester form. 6. 6. It was concluded that the exocellular phosphomannan was not a product of autolysis of the cell wall material but rather an independently synthesized material.

<i>Rhodotorula glutinis</i>が生産する多糖の糖組成について

Twelve strains of Rhodotorula glutinis were cultured under shaking in an acidic medium to investigate the sugar compositions of extracellular polysaccharides. Polysaccharides produced were separated from the medium by acetone precipitation and the sugar compositions were analyzed by gas-liquid chromatography. The results showed that extracellular polysaccharides of R. glutinis generally consisted of mannose, fucose, and galactose. A strain, IFO 1223, lacked fucose, but contained xylose instead. IFO 0667 contained glucose, which was not found in the other strains. Mannose was the most predominant component in all the strains with the exception of K-24, which produced polysaccharides consisting mostly of fucose and galactose. It was suggested that there were at least two kinds of polysaccharides, one was composed predominantly of mannose and the other of fucose and galactose. In a neutral medium, AJ 4859 produced polysaccharides containing 94% fucose.

Biochemical and Immunological Studies onAspergillus

Two kinds of polysaccharides, glucan and glycopeptide (galactomannan-peptide), were obtained from Aspergillus fumigatus (IFO 5840) by extraction with 50% pyridine and were purified by fractional precipitation with acetone, by a column chromatography on Dowex-50 and DEAE-cellulose and by the gel filtration on Sephadex G-50 and G-200. The glycopeptide, designated APSK-66 fraction, showed both an Arthus and delayed type (tuberculin type) skin reactions in sensitized rabbits and guinea pigs. By treatment with proteolytic enzymes, the delayed type skin reactivity of APSK-66 fraction was reduced but the Arthus type skin reactivity was not affected. However, the Arthus type skin reactivity of APSK-66 fraction was completely lost by periodate oxidation, and the delayed type skin reactivity of APSK-66 fraction was retained. The APSK-66 fraction showed precipitation, complement fixation and passive hemagglutination reactions with rabbit antisera against A. fumigatus. Glucan, designated as APSK-33 fraction, did not show any immunological activity when tested in the present experiment. The chemical structures of the glucan and galactomannan were discussed.

Polysaccharides of Mycobacterium bovis Ushi 10, Mycobacterium smegmatis, Mycobacterium phlei , and Atypical Mycobacterium P1

Four kinds of polysaccharides, glucan, mannan, arabinomannan, and arabinogalactan, were purified from the defatted cells of four strains of mycobacteria. By the chemical and immunological analyses, we concluded that arabinomannan and arabinogalactan are common serologically active polysaccharides in mycobacteria.

Etude des polysaccharides de réserve de deux graines de liliacées: Asparagus officinalis L., et Endymion nutans dumort

The seeds of Asparagus officinalis and Endymion nutans contain large quantities of NaOH-soluble polysaccharides. These hemicelluloses are linear molecules consisting of β-glucose and β-mannose 1→4 linked with α-galactose as a terminal group. The seeds of Asparagus are containing only one type of glucomannan (for which the ratio mannose/glucose=1) whereas those of Endymion seem to have at least two kinds of polysaccharide, differentiated by the mannose/glucose ratio.

Polysaccharide constituents in fulvic and humic acids extracted from soil

Soil humic materials extracted from three dissimilar soil profiles were studied by infra-red spectroscopy. Carbohydrates in the form of polysaccharides were present in close relation or as constituent components in the fulvic and hymatomelanic acids encountered in both the surface and deeper layers of the soils examined. The fractionation procedure that yielded polysaccharide from hymatomelanic acid failed to do so when used on humic acid. At least two kinds of polysaccharides were encountered - those from fulvic acid, with a single peak at 1,650 cm −1, and those from hymatomelanic acid, with twin peaks at 1,650 cm −1 and 1,400 cm −1. Fulvic acid in acid brown forest soil formed under pine vegetation had a stronger phenolic or lignoid character and a weaker polysaccharide character than did fulvic acid in a chestnut and an alluvial soil formed under grass vegetation. This difference was especially pronounced in the surface soil, but disappeared in the subsoil. The infra-red spectra of polysaccharides in the hymatomelanic acids of the surface layers of the three soils were, however, surprisingly similar.

Biochemical and Immunological Studies on Aspergillus

Lipopolysaccharide, protein and polysaccharide fractions were extracted and purified from A. fumigatus. Pyrogenic activity for rabbits was found by the intravenous injection of lipopolysaccharide at 0.125 mg doses.The protein fraction was active in delayed type skin reaction at 10 μg in the rabbits of experimental aspergillosis. Purified protein fraction (AAP-A) contained 13.48 per cent of nitrogen and a small amount of sugar.Two kinds of polysaccharide, APS-33 and APS-66, were extracted and purified by the fractional precipitation with acetone, column chromatography on Dowex 50 and DEAE cellulose column and gel filtration. Precipitation antigenicity was shown in APS-66 using antiserum of the rabbits of experimental aspergillosis. The skin-test antigenicity was not found in both purified polysaccharide fractions. By the gas-liquid chromatographic analysis of sugar component, it was shown that APS-33 was composed of glucose only and APS-66 was composed of galactose and mannose. The molecular weight of both polysaccharides was larger than 50, 000.

Type-Specific Polysaccharides of C. diphtheriae.

Polysaccharides derived from gravis, intermediate, and mitis types of C. diphtheriœ were found to be group-specific. Recent findings, however, indicate that any of these different cultural types may be present in a single serological type. Because of this an attempt was made to extend our previous study to include polysaccharides of different serological types of C. diphtheriœ with the object of determining the existence of type-specific polysaccharides. One organism from each of 5 distinct serological types kindly supplied to us by Sia and Huang was employed for the present study. All organisms, with the exception of Park 8 (Type D41) were isolated locally. The various characterizations of these organisms were as follows: All of the cultures were capable of eliciting precipitin antibodies in rabbits from 4 to 5 weeks when administered intravenously as heat-killed vaccines. The cultivation of organisms, the preparation of polysaccharides, and the immunization of rabbits were the same as those described previously. Absorption test was performed by mixing immune serum diluted 1:5 with well-washed living organisms grown on serum broth at 37°C for 48 hours and the mixture was incubated at 45°C waterbath for 2 hours. It was refrigerated overnight after which the serum was separated by rapid centrifugation. It was found that 2 kinds of polysaccharide could be demonstrated by the precipitin reaction and by absorption tests. These polysaccharides will be designated as A and B. Polysaccharide A was present in the types D25, D30, D41, and X. Identical precipitin titers varying from 1:50,000 to 1:100,000 were obtained when polysaccharides A were mixed in the ring test with the homologous as well as the heterologous immune sera prepared with the above types. Cross absorption tests performed by mixing immune serum with organisms belonging to any of the types D25, D30, D41, and X showed a removal of all precipitins without affecting the type-specific agglutinins.