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1.
Hee-Kyoung Jung Joo-Heon Hong Seung-Chun Park Byung-Kwon Park Doo-Hyun Nam Sang-Dal Kim 《Biotechnology and Bioprocess Engineering》2007,12(6):713-719
This study was conducted to develop a bacterial glucan as an animal feed additive. A novel glucan-producing bacterium.Paenibacillus polymyxa JB115, was isolated from Korean soil. The glucan, JB115-BG, produced byP. polymyxa JB115, was confirmed by TLC to be composed of glucose only. By examining FT-IR,1H NMR, and13C NMR spectra, it was proven that JB115-BG has a β-(1→3)- and β-(1→6)-linked glucan structure. The particle size of JB115-BG
was distributed in the range of 4–800 μm, with a mean value of 149.1 μm, and its molecular distribution ranged from 6.9∼3,103.7
kDa. It was also observed that 80% of the purified JB115-BG had a molecular distribution above 100 kDa. The obtained results
suggest that the glucan JB115-BG can be used as an animal feed additive for the purpose of enhancing immunity. 相似文献
2.
Graham J. C. Underwood Matthew Boulcott Christine A. Raines Keith Waldron 《Journal of phycology》2004,40(2):293-304
Marine benthic diatoms excrete large quantities of extracellular polymeric substances (EPS), both as a function of their motility system and as a response to environmental conditions. Diatom EPS consists predominantly of carbohydrate‐rich polymers and is important in the ecology of cells living on marine sediments. Production rates, production pathways, and monosaccharide composition of water‐soluble (colloidal) carbohydrates, EPS, and intracellular storage carbohydrate (glucans) were investigated in the epipelic (mud‐inhabiting) diatoms Cylindrotheca closterium (Ehrenburg), Navicula perminta (Grün.) in Van Heurck, and Amphora exigua Greg. under a range of experimental conditions simulating aspects of the natural environment. Cellular rates of colloidal carbohydrate, EPS, and glucan production were significantly higher during nutrient‐replete compared with nutrient‐limited growth for all three species. The proportion of EPS in the extracellular carbohydrate pool increased significantly (to 44%–69%) as cells became nutrient limited. Cylindrotheca closterium produced two types of EPS differing in sugar composition and production patterns. Nutrient‐replete cells produced a complex EPS containing rhamnose, fucose, xylose, mannose, galactose, glucose, and uronic acids. Nutrient‐limited cells produced an additional EPS containing mannose, galactose, glucose, and uronic acids. Both EPS types were produced under illuminated and darkened conditions. 14C‐labeling revealed immediate production of 14C‐glucan and significant increases in 14C‐EPS between 3 and 4 h after addition of label. The glucan synthesis inhibitor 2,6‐dichlorobenzonitrile significantly reduced 14C‐colloidal carbohydrate and 14C‐EPS. The glucanase inhibitor P‐nitrophenyl β‐d ‐glucopyranoside resulted in accumulation of glucan within cells and lowered rates of 14C‐colloidal and 14C‐EPS production. Cycloheximide prevented glucan catabolism, but glucan production and EPS synthesis were unaffected. 相似文献
3.
Tissue slices from developing potato tubers (Solanum tuberosum L.) and developing cotyledons of faba bean (Vicia faba L.) were incubated with specifically labelled [13C]glucose and [13C]ribose. Enriched[13C]glucose released from starch granules was analysed by nuclear magnetic resonance (NMR). Spectral analyses were also performed on sucrose purified by high-performance liquid chromatography. In both tissues a low degree of randomisation (< 11 % in potato and < 14% in Vicia) was observed between carbon positions 1 and 6 in glucose released from starch when material was incubated with [13C]glucose labelled in positions 6 and 1, respectively. Similarly, with [2-13C]glucose a low degree of randomisation was observed in position 5. These findings indicate that extensive transport of three-carbon compounds across the amyloplast membrane does not occur in storage organs of either species. This is in agreement with previously published data which indicates that sixcarbon compounds are transported into the plastids during active starch synthesis. When [1-13C]ribose was used as a substrate, 13C-NMR spectra of starch indicated the operation of a classical pentose-phosphate pathway. However, with [2-13C]glucose there was no preferential enrichment in either carbon positions 1 or 3 relative to 4 or 6 of sucrose and starch (glucose). This provides evidence that entry of glucose in this pathway may be restricted in vivo. In both faba bean and potato the distribution of isotope between glucosyl and fructosyl moieties of sucrose approximated 50%. The degree of randomisation within glucosyl and fructosyl moieties ranged between 11 and 19.5%, indicating extensive recycling of triose phosphates.Abbreviation NMR
nuclear magnetic resonance
We are grateful to Dr. George Ratcliffe for his critical reading of the text and Dr. Bernard Goodman for helpful suggestions on the NMR measurements. The research was funded by a European Economic Community research grant, which the authors duly acknowledge. 相似文献
4.
Sushma Deepthi Arli U. B. Trivedi K. C. Patel 《World journal of microbiology & biotechnology》2011,27(6):1415-1422
Cellulomonas flavigena UNP3, a natural isolate from vegetable oil contaminated soil sample has been studied for growth associated exopolysaccharide
(EPS) production during growth on glucose, groundnut oil and naphthalene. The EPS showed matrix formation surrounding the
cells during scanning electron microscopy. Cell surface hydrophobicity and emulsifying activity studies confirmed the role
of EPS as bioemulsifier. Emulsifying activity was found to increase with time (0.2 U/mg for 10 min to 0.27 U/mg for 30 min).
Emulsification index, E24 value increased with the increase in EPS concentration. Degradation of polyaromatic hydrocarbons was confirmed using gas
chromatography analysis. FTIR analysis showed presence of characteristic absorbance at 895.10 cm−1 for β-configuration of glucan. NMR studies also revealed EPS produced by C. flavigena UNP3 as a linear β-1, 3-d-glucan, and a curdlan like polysaccharide. 相似文献
5.
Production of exopolysaccharides from a thermophilic microorganism isolated from a marine hot spring in flegrean areas 总被引:5,自引:0,他引:5
Schiano Moriello V Lama L Poli A Gugliandolo C Maugeri TL Gambacorta A Nicolaus B 《Journal of industrial microbiology & biotechnology》2003,30(2):95-101
A thermophilic strain isolated from sea sand at Maronti, near Sant' Angelo (Ischia), is described. The organism grows well
at an optimal temperature of 60 °C at pH 7.0. The thermophilic bacterium, named strain 4004, produces an exocellular polysaccharide
(EPS) in yields of 90 mg/l. The EPS fraction was produced with all substrates tested, although a higher yield was obtained
with sucrose or trehalose as sole carbon source. During growth, the EPS content was proportional to the biomass. Three fractions
(EPS1, EPS2, EPS3) were obtained after purification. Quantitative monosaccharide analysis of the EPSs revealed the presence
of mannose:glucose:galactose in a relative ratio of 0.5:1.0:0.3 in EPS1, mannose:glucose:galactose in a relative ratio of
1.0:0.3:trace in EPS2, and galactose:mannose:glucosamine:arabinose in a relative ratio of 1.0:0.8:0.4:0.2 in EPS3. The average
molecular mass of EPS3 was determined to be 1×106 Da. From comparison of the chemical shift values in 1H and 13C spectra, we conclude that EPS3 presents a pentasaccharide repeating unit.
Electronic Publication 相似文献
6.
S. V. N. Vijayendra G. Palanivel S. Mahadevamma R. N. Tharanathan 《Archives of microbiology》2009,191(4):303-310
A heterofermentative Lactobacillus sp. CFR-2182 was isolated from dahi samples and it was found to produce 8.0 and 20.5 g/L heteropolysaccharide (HePS) in EPS medium (a simplified synthetic medium)
and modified MRS broth, respectively, after 72 h at 30°C. The total carbohydrate, reducing sugar and moisture contents of
the purified HePS were 74, 10.6 and 2 g, respectively, per 100 g on dry weight basis. The HePS produced in EPS medium had
glucose and mannose in 17:1 ratio. The HePS was non-gelling and non-film forming type. It was completely soluble in water
and 1 N sodium hydroxide solution. Gel permeation chromatography and HPLC analysis indicated considerable heterogeneity of
the HePS, having three fractions with molecular weights ranging from 3.3 × 104 to 1.32 × 106 Da. The enzymatic hydrolysis of the HePS with pullulanase and α-amylase [with α(1→4) linkage] indicated the presence of α(1→6)
and traces of α(1→4) linkages, respectively. NMR analysis of the EPS revealed unique chemical shifts. 相似文献
7.
Gluconobacter oxydans that produces the cellulose was isolated. In order to confirm the chemical features of cellulose, various spectrophtometeric
analysis were carried out using electron microscopy, X-ray diffractogram, and CP/MAS13C NMR. The purified cellulose was found to be identical to that ofAcetobacter xylinum. For effective production of cellulose, the various carbon and nitrogen sources, mixture of calcium and magnesium ions, and
biotin concentration were investigated in flask cultures. Among the various carbon sources, glucose and sucrose were found
to be best for the production of cellulose, with maximum concentration of 2.41 g/L obtained when a mixture of 10 g/L of each
glucose and sucrose were used. With regard to the nitrogen sources, when 20 g/L of yeast extract was used, the maximum concentration
of bacterial cellulose was reached. The concentration of cellulose was increased with mixture of 2 mM of each Ca2+ and Mg2+. The optimum biotin concentration for the production of cellulose was in the range of 15 to 20 mg/L. At higher biotin concentration
(25–35 mg/L), the bacterial cellulose production was lower. 相似文献
8.
A moderately halophilic bacterium, Halomonas xianhensis SUR308 (Genbank Accession No. KJ933394) was isolated from a multi-pond solar saltern at Surala, Ganjam district, Odisha, India. The isolate produced a significant amount (7.87 g l?1) of extracellular polysaccharides (EPS) when grown in malt extract–yeast extract medium supplemented with 2.5% NaCl, 0.5% casein hydrolysate and 3% glucose. The EPS was isolated and purified following the conventional method of precipitation and dialysis. Chromatographic analysis (paper, GC and GC-MS) of the hydrolyzed EPS confirmed its heteropolymeric nature and showed that it is composed mainly of glucose (45.74 mol%), galactose (33.67 mol %) and mannose (17.83 mol%). Fourier-transform infrared spectroscopy indicated the presence of methylene and carboxyl groups as characteristic functional groups. In addition, its proton nuclear magnetic resonance spectrum revealed functional groups specific for extracellular polysaccharides. X-ray diffraction analysis revealed the amorphous nature (CIxrd, 0.56) of the EPS. It was thermostable up to 250°C and displayed pseudoplastic rheology and remarkable stability against pH and salts. These unique properties of the EPS produced by H. xianhensis indicate its potential to act as an agent for detoxification, emulsification and diverse biological activities. 相似文献
9.
Cellulose solvent-based biomass pretreatment breaks highly ordered hydrogen bonds in cellulose fibers of switchgrass 总被引:1,自引:0,他引:1
The switchgrass (SG) samples pretreated by cellulose solvent‐ and organic solvent‐based lignocellulose fractionation were characterized by enzymatic hydrolysis, substrate accessibility assay, scanning electron microscopy, X‐ray diffraction (XRD), cross polarization/magic angle spinning (CP/MAS) 13C nuclear magnetic resonance (NMR), and Fourier transform infrared spectroscopy (FTIR). Glucan digestibility of the pretreated SG was 89% at hour 36 at one filter paper unit of cellulase per gram of glucan. Crystallinity index (CrI) of pure cellulosic materials and SG before and after cellulose solvent‐based pretreatment were determined by XRD and NMR. CrI values varied greatly depending on measurement techniques, calculation approaches, and sample drying conditions, suggesting that the effects of CrI data obtained from dried samples on enzymatic hydrolysis of hydrated cellulosic materials should be interpreted with caution. Fast hydrolysis rates and high glucan digestibilities for pretreated SG were mainly attributed to a 16.3‐fold increase in cellulose accessibility to cellulase from 0.49 to 8.0 m2/g biomass, because the highly ordered hydrogen‐bonding networks in cellulose fibers of biomass were broken through cellulose dissolution in a cellulose solvent, as evidenced by CP/MAS 13C‐NMR and FTIR. Biotechnol. Bioeng. 2011; 108:521–529. © 2010 Wiley Periodicals, Inc. 相似文献
10.
The metabolism of Spironucleus vortens, a parasitic, diplomonad flagellate related to Giardia intestinalis, was investigated using a combination of membrane inlet mass spectrometry, 1H NMR, 13C NMR, bioscreen continuous growth monitoring, and ion exchange chromatography. The products of glucose-fuelled and endogenous metabolism were identified by 1H NMR and 13C NMR as ethanol, acetate, alanine and lactate. Mass spectrometric monitoring of gas metabolism in buffered cell suspensions showed that glucose and ethanol could be used by S. vortens as energy-generating substrates, but bioscreen automated monitoring of growth in culture medium, as well as NMR analyses, suggested that neither of these compounds are the substrates of choice for this organism. Ion-exchange chromatographic analyses of free amino-acid and amino-acid hydrolysate of growth medium revealed that, despite the availability of large pools of free amino-acids in the medium, S. vortens hydrolysed large amounts of proteins during growth. The organism produced alanine and aspartate, and utilised lysine, arginine, leucine, cysteine and urea. However, mass spectrometric and bioscreen investigations showed that addition of the utilised amino acids to diluted culture medium did not induce any significant increase in metabolic or growth rates. Moreover, as no significant amounts of ornithine were produced, and addition of arginine under aerobic conditions did not generate NO production, there was no evidence of the presence of an energy-generating, arginine dihydrolase pathway in S. vortens under in vitro conditions. 相似文献
11.
Bhunia SK Dey B Maity KK Patra S Mandal S Maiti S Maiti TK Sikdar SR Islam SS 《Carbohydrate research》2011,(13):2039-2044
A water-soluble glucan, isolated from the alkaline extract of the fruit bodies of an edible mushroom, Lentinus squarrosulus (Mont.) Singer was found to consist of (1→3,6)-linked, (1→3)-linked, (1→6)-linked, and terminal β-d-glucopyranosyl moieties in a relative proportion of approximately 1:2:1:1. This polysaccharide showed optimum activation of macrophages as well as splenocytes and thymocytes at 10 μg/mL. Structural investigation was carried out using sugar analysis, methylation analysis, periodate oxidation study, and NMR experiments (1H, 13C, DEPT-135, DQF-COSY, TOCSY, NOESY, ROESY, HMQC, and HMBC). On the basis of above-mentioned experiments, the structure of the repeating unit of the polysaccharide was established as: 相似文献
12.
Juçara palm tree is considered an important species in the Atlantic forest ecosystem and the exploitation of its fruits is a main sustainable strategy adopted to its maintenance. Among several microorganisms in the juçara fruits, were found lactic acid bacteria (LAB) highly capable of synthesizing exopolysaccharides (EPS). Thus, the EPS synthesized by Leuconostoc pseudomesenteroides JF17 was characterized according to its chemical structure, physicochemical properties and antioxidant activity. HPLC analysis showed that the EPS consisted of a homopolysaccharide composed of glucose units, FT-IR spectroscopy revealed a dextran, confirmed by 1H and 13C NMR spectra which showed the composition of the polysaccharide, d-glucose units bound by α-(1→6). The EPS showed high water retention capacity, 507.812 ± 47.471 %, and may be related to the porous structure revealed by SEM images. Thermal analysis indicated that the EPS had excellent thermal stability with degradation temperature of 320.8 °C and melting point at 279.81 °C, with the enthalpy of 106.557 J/g. The EPS also presented sequestration ability on different free radicals tested, indicating high antioxidant activity. The results suggest that L. pseudomesenteroides JF17 might be widely used in the production of dextran which has potential qualities for applications in the food industry. 相似文献
13.
Biosynthetically directed fractional 13C labeling, a popular methodology of metabolic flux analysis, involves culture on a mixture of 13C and 12C substrates and preparation a ‘metabolic flux analyte’ (typically protein hydrolysate) from the biomass. Metabolic flux analytes prepared from complex eukaryotes may contain additional compounds than those prepared from microorganisms. We report the presence of such compounds (hexose hydrolysis products) in a plant metabolic flux analyte (acid hydrolyzed protein from soybean embryos). We designed NMR experiments to systematically identify these compounds, and found that they were levulinic acid (LVA; major) and hydroxyacetone (HyA; minor). These acid hydrolysis products of hexoses (glucose and mannose) were generated during acid hydrolysis of glycosylating sugars (glucosamine and mannose) associated with soybean embryo protein. Analysis of LVA by two-dimensional [13C, 1H] NMR and measurement of its J-coupling constants revealed long-range coupling between atoms C3 and C5, which enables LVA to provide more isotopomer information than its precursor hexose. Furthermore, we found that LVA and HyA preserve the isotopomeric composition of the metabolic hexose from which they are derived. An important consequence of these results is that comparison of LVA and HyA isotopomers from two separate metabolic flux analytes (protein hydrolysate and starch hydrolysate) from the same plant tissue can distinguish between parallel glycolysis and pentose phosphate pathways in different subcellular compartments. 相似文献
14.
Incorporation of radioactive glucose in growing apices of Saprolegnia monoïca hyphae were examined by electron microscopic autoradiography. 3H glucose labelling indicates that dictyosomes and apical vesicles do not contain much polysaccharide and that glucan synthesis occurs at the cell surface. 14C glucose labelling shows that incorporation was chased from the cell walls during hyphal morphogenesis. 相似文献
15.
Epipelic diatoms are important constituents of estuarine microphytobenthic biofilms. Field‐based investigations have shown that the production of carbohydrates by such taxa is ecologically important. However, limited information exists on the dynamics of carbohydrate production by individual species of epipelic diatoms. The production of low and high molecular weight extracellular carbohydrates in axenic cultures of five species of benthic estuarine diatoms, Cylindrotheca closterium (Ehrenberg), Navicula perminuta (Grun.) in Van Heurck, Nitzschia frustulum (Kütz.) Grunow, Nitzschia sigma (Kütz.) Grunow, and Surirella ovata (Kütz.) Grunow, were investigated. All species produced colloidal (water‐soluble) carbohydrates during growth, with maximal production occurring during stationary phase. During logarithmic growth, approximately 20% of extracellular carbohydrates consisted of polymeric material (extracellular polymeric substances [EPS]), but during stationary phase, EPS content increased to 34%–50%. Pyrolysis–mass spectrophotometry analysis showed differences in the composition of EPS produced during logarithmic and stationary phase. All species synthesized glucan as a storage carbohydrate, with maximum glucan accumulation during the transition from log to stationary phase. Short‐term labeling with 14C‐bicarbonate found that between 30 and 60% of photoassimilates were released as colloidal carbohydrate, with EPS consisting of approximately 16% of this colloidal fraction. When cells were placed in darkness, EPS production increased, and between 85 and 99% of extracellular carbohydrate produced was polymeric. Glucan reserves were utilized in dark conditions, with significant negative correlations between EPS and glucan for N. perminuta and S. ovata. Under dark conditions, cells continued to produce EPS for up to 3 days, although release of low molecular weight carbohydrates rapidly ceased when cells were dark treated. Three aspects of EPS production have been identified during this investigation: (1) production during rapid growth, which differs in composition from (2) EPS directly produced as a result of photosynthetic overflow during growth limiting conditions and (3) EPS produced for up to 3 days in the dark using intracellular storage reserves (glucans). The ecological implications of these patterns of production and utilization are discussed. 相似文献
16.
M. Nishina K. Matsushita E. Hori M. Takahashi K. Kato 《Entomologia Experimentalis et Applicata》1993,66(3):269-274
Nuclear magnetic resonance (NMR) technology was applied to study the glucose metabolism inTribolium confusum (Coleoptera).13C signals of D-(1-13C)glucose eaten by beetles were clearly detected in such metabolites of the glucose metabolism as glycogen, trehalose, triacylglycerol,
alanine and proline by13C-NMR. After glucose feeding the31P-NMR spectra ofT. confusum showed the signal intensity increases in arginine-phosphate, sugar-phosphate and uridine diphosphoglucose. The results demonstrated
the potential of NMR analysis for the study of glucose metabolism inT. confusum. 相似文献
17.
Ulrich Metzger Ulrich Lankes Kai Fischpera Fritz H. Frimmel 《Applied microbiology and biotechnology》2009,85(1):197-206
Extracellular polymeric substances were extracted from the bacterial strain Pseudomonas putida and the fungal species Aureobasidium pullulans using three different methods (formaldehyde–NaOH, ethylenediaminetetraacetic acid (EDTA) and cation-exchange-resin). The
composition of the extracellular polymeric substances (EPS) was analysed by biochemical and high-resolution solid state 13C nuclear magnetic resonance (NMR) spectroscopic methods. The EPS yield was strongly dependent on the extraction method, with
the formaldehyde–NaOH method showing the best extraction efficiency. The NMR method revealed that when using the EDTA extraction
method, about 40% of the EDTA accumulated in the EPS and that was responsible for the apparent high extraction yields. EPS
protein content determined by the NMR method was up to 30% higher than the protein content determined using the biochemical
(Lowry) method for P. putida and for A. pullulans. The average protein carbon content determined by the NMR method was approximately 70% of the total carbon content. NMR results
could be supported by elemental analysis, which showed a high nitrogen content (~10%) in the EPS. The carbohydrate carbon
content detected with both methods in the cell aggregates and the EPS was approximately 20% in each. In this study, quantitative
13C cross-polarisation magic angle spinning NMR spectroscopy was conducted on unlabeled cell strains, and EPS and could be used
to quantify protein and carbohydrate of different samples. 相似文献
18.
Vasu D. Appanna 《Antonie van Leeuwenhoek》1989,56(4):357-360
Exopolysaccharide (EPS) elaborated by Rhizobium meliloti JJ-1 in a manganese supplemented medium was isolated. Periodate oxidation, reduction with sodium borohydride, followed by hydrolysis and subsequent capillary gas liquid chromatography of the derived alditol acetates revealed that D-galactose in this complex biopolymer is in furanoid form. This observation was further confirmed by 13carbon nuclear magnetic resonance (13C NMR). 相似文献
19.
Incorporation of UDPGlucose into Cell Wall Glucans and Lipids by Intact Cotton Fibers 总被引:2,自引:2,他引:0
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The [14C] moiety from [3H]UDP[14C]glucose was incorporated by intact cotton fibers into hot water soluble, acetic-nitric reagent soluble and insoluble components, and chloroform-methanol soluble lipids; the [3H] UDP moiety was not incorporated. The 3H-label can be exchanged rapidly with unlabeled substrate in a chase experiment. The cell wall apparent free space of cotton fibers was in the order of 30 picomoles per milligram of dry fibers; 25 picomoles per milligram easily exchanged and about 5 picomoles per milligram more tightly adsorbed. At 50 micromolar UDPglucose, 70% of the [14C]glucose was found in the lipid fraction after both a short labeling period and chase. The percent of [14C]glucose incorporated into total glucan increased slightly with chase, but the fraction of total glucans incorporated into insoluble acetic-nitric reagent (cellulose) did increase within a 30-minute chase period. The data supports the concept that glucan synthesis, including cellulose, as well as the synthesis of steryl glucosides, acetylated steryl glucosides, and glucosyl-phosphoryl-polyprenol from externally supplied UDPglucose occurs at the plasma membrane-cell wall interface. The synthase enzymes for such synthesis must be part of this interfacial membrane system. 相似文献
20.
Aparna Banerjee Shalini Gaur Rudra Koushik Mazumder Vinod Nigam Rajib Bandopadhyay 《Indian journal of microbiology》2018,58(1):39-50
Exopolysaccharide produced by a unique avirulent Bacillus anthracis strain PFAB2 of hot spring origin has been characterized and its functional properties are investigated which is a first report. Maximum yield of EPS is 7.66 g/l with 2% glucose and 1% peptone as optimum carbon and nitrogen source respectively. The EPS is found to be a homopolymer consisting of only glucose as principle monosaccharide component. Through 1H NMR study, different dextran-like proton peaks are observed. Molecular weight of the EPS resembles low molecular weight bacterial origin polysaccharides. Melting transition of the EPS has started after 276 °C which indicates good thermal stability. The EPS also shows potent antioxidant activity in terms of DPPH and ABTS mediated free radical scavenging property compared to standard ascorbic acid. Emulsifying property of the EPS is also observed and has shown good emulsification of vegetable oils. The polysaccharide forms a thermo resistant gel during the heating phase, with G′ higher than G″ indicating excellent shear-thinning behaviour and viscoelastic nature of the EPS. 相似文献