Polysaccharides from the stems ofAlthea nudiflora

From the heart of the stems of the hollyhockAlthea nudiflora (Lindl.) Boiss., growing on the territory of Southern Kazakhstan we have isolated a polysaccharide (yield 5%) containing residues of glucuronic and galacturonic acids (totalling 42%), and also of glucose, rhamnose, galactose, arabinose, xylose (traces) and mannose (traces). From the bark of the stems of this plant we have isolated a polysaccharide (yield 1.8%) consisting of a branched polymer composed of residues of rhamnose, glucose, and arabinose (22:17:2) and also of glucuronic and galacturonic acids (totalling 30%). In the products of the methylation of this polysaccharide previously reduced at the COOH groups we have established the presence of 2,3,4-tri-O-methylrhamnose, 3,4-di-O-methylrhamnose, 2,3,4,6-tetra-O-methylglucose, 2,6-di-O-methylglucose, and a mixture of 2,3,6-tri-O-methylglucose and 2,3,6-tri-O-methylgalactose (1:10:14:5:7).V. L. Komarov Botanical Institute, Academy of Sciences of the USSR, Leningrad. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 145–148, March–April, 1980.     

A new method for quantitative determination of two uronic acids by CZE with direct UV detection

A new method using capillary zone electrophoresis was developed for the rapid quantification of two common uronic acids, galacturonic acid and glucuronic acid, based on utilization of an alkaline background electrolyte with reversed electroosmotic flow (EOF) within 16 min. The method relies on in‐capillary reaction and direct UV detection at the wavelength 270 nm. The optimum electrolyte solution was prepared of 130 mm sodium hydroxide, 36 mm disodium hydrogen phosphate dihydrate and 0.5 mm cetyltrimethylammonium bromide. EOF was reversed to detect uronic acids and to improve the separation of neutral sugars. The established method was validated and the results showed good linearity, high precision and satisfactory sensitivity. The newly developed method was successfully applied to analyze galacturonic acid and glucuronic acid content in Forsythia suspensa polysaccharides. The method is fast since only sample hydrolysis and dilution are required in the sample preparation. Copyright © 2010 John Wiley & Sons, Ltd.     

Capillary Zone Electrophoresis with Amperometric Detection for Composition Analysis of Laminarin

IntroductionInrecentdecades ,manykindsofplantpolysaccha rideshavebeenextensivelystudiedfortheirpotentialvalueinimmunology ,especiallyincancertherapeusis .Laminar in ,onekindofheteropolysaccharidesisolatedfromLami nariajaponica ,wasfoundtobeoneoftheinhibitorsofba sicfabriccell generationfactor (bFGF)anddepresstheformationoftubestructureofendothelialcells ,whichfur therdepresstheactivationofrats’cancercells .1Itwasal sofoundthatlaminarinsulfatecouldinhibitextracellularmatrix (ECM)degradation…     

气相色谱-质谱联用同时分析新型细菌多糖中的单糖和糖醛酸

对纯化的新型细菌多糖进行酸水解,用乙硫醇-三氟乙酸和醋酐-吡啶体系先后对酸水解物进行衍生,与之前报道不同的是糖醛酸得到有效衍生化。以木糖为内标,采用气相色谱-质谱联用(GC-MS)定量分析该多糖酸水解物中单糖和糖醛酸衍生物发现,该多糖的糖链由岩藻糖、葡萄糖、葡萄糖醛酸和半乳糖组成,其相对物质的量比为1.50:1.0:0.79:2.06;中性糖比例与糖醇乙酸酯化分析岩藻糖、葡萄糖和半乳糖的相对物质的量比(1.76:1.0:1.98)接近;糖醛酸咔唑法与该方法分析葡萄糖醛酸的含量分别为16.19%和14.85%。以上结果表明所建立的衍生化方法及GC-MS同时定量分析多糖酸水解物中单糖和糖醛酸的方法可行。此外还对葡萄糖醛酸的质谱裂解机理进行了阐述。     

超高效液相色谱-串联质谱法测定螺旋藻多糖的单糖组成

建立了同时测定螺旋藻多糖水解产物中鼠李糖、木糖、阿拉伯糖、果糖、甘露糖、葡萄糖、半乳糖、甘露醇、核糖、岩藻糖、葡萄糖醛酸、半乳糖醛酸12种糖类化合物的超高效液相色谱-串联质谱分析方法。螺旋藻样品经超声波辅助提取,用三氟乙酸水解,经Waters Acquity BEH Amide色谱柱(100 mm×2.1 mm,1.7μm)分离,以10mmol/L甲酸铵和10 mmol/L甲酸铵-乙腈为流动相,在电喷雾电离源负离子(ESI-)模式下,用多反应监测(MRM)模式检测。结果表明,12种糖类化合物的定量限为0.005~0.15 mg/kg,线性范围为0.05~5 mg/L。按照样品中每种糖本底含量的50%、100%、150%进行添加,回收率为80.21%~121.6%。应用该方法对螺旋藻样品进行分析,结果发现:大部分样品都能检测到岩藻糖、半乳糖、阿拉伯糖、鼠李糖、葡萄糖、果糖、木糖、核糖,含量在0.3~889.4 mg/g之间。此外,测定的15个样品中岩藻糖、半乳糖、阿拉伯糖、鼠李糖、葡萄糖、果糖、木糖、核糖是共有组分,含量差异较大,但在所有样品中均未检测到甘露醇和甘露糖。该方法的建立可为阐明螺旋藻多糖的结构组成及其活性提供技术支撑及基础数据。     

Determination of glycuronic acids by high-performance anion chromatography with pulsed amperometric detection

Summary Acid hydrolysis (0.25M H₂SO₄) coupled with enzyme catalysis (pectolyase and β-D-glucuronidase) were employed to extract galacturonic and glucuronic acids from microbial polysaccharides, plant residues, animal wastes, sewage sludge and soil. The glycuronic acids were separated by high-performance anion chromatography (HPAC) on a strong anion-exchange column using 0.1M sodium hydroxide with 0.25M sodium acetate as the mobile phase and determined by pulsed amperometric detection (PAD). HPAC-PAD was found to be superior to high-performance liquid chromatography with ultra-violet (UV) detection in terms of resolution and sensitivity of glycuronic acids. HPAC-PAD was not subject to interferences present with low UV detection (210 nm) and was highly selective for glycuronic acids. Enzymatic hydrolysis after treatment with mild acid (0.25M H₂SO₄) released galacturonic acids from orange peel and pectin, while glucuronic acid was released from Acacia powder. Large amounts of glycuronic acids were also extracted from plant materials. Low levels of uronic acids were detected in poultry manure, sewage sludge and organic-amended soils.     

Xylooligosaccharides Production from Alkali-Pretreated Sugarcane Bagasse Using Xylanases from Thermoascus aurantiacus

Sugarcane bagasse hemicellulose was isolated in a one-step chemical extraction using hydrogen peroxide in alkaline media. The polysaccharide containing 80.9% xylose and small amounts of l-arabinose, 4-O-methyl-d-glucuronic acid and glucose, was hydrolyzed by crude enzymatic extracts from Thermoascus aurantiacus at 50?°C. Conditions of enzymatic hydrolysis leading to the best yields of xylose and xylooligosaccharides (DP 2-5) were investigated using substrate concentration in the range 0.5–3.5% (w/v), enzyme load 40–80 U/g of the substrate, and reaction time from 3 to 96 h, applying a 2² factorial design. The maximum conversion to xylooligosaccharides (37.1%) was obtained with 2.6% of substrate and xylanase load of 60 U/g. The predicted maximum yield of xylobiose by a polynomial model was 41.6%. Crude enzymatic extract of T. aurantiacus generate from sugarcane bagasse hemicellulose 39% of xylose, 59% of xylobiose, and 2% of other xylooligosaccharides.     

Preliminary investigation of the water-soluble polysaccharides from the leaves of the bambooSasamorpha chiisanensis

It has been shown that the water-soluble polysaccharides of the leaves of the bambooSasamorpha chiisanensis Nak., after the removal of starch, contain residues of D-galactose, D-glucose, mannose, arabinose, D-xylose, rhamnose, and glucuronic and galacturonic acids and form an involved polysaccharide complex. Eight polysaccharide fractions differing in their uronic acid contents and in the ratio of neutral sugars have been isolated with the aid of chromatography on DEAE-cellulose.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 44–48, January–February, 1987.     

Simultaneous Estimation of 4-O-Methyl-D-Glucuronic Acid and Other Uronic Acids By Gas-Liquid Chromatography

Abstract

Uronic acids in polysaccharides may be reduced by reaction of the propionated methyl ester with lithium borohydride in tetrahydrofuran. After hydrolysis and reduction of the monosaccharides the acetylated alditols may be separated by gas-liquid chromatography on a column of butanediol succinate. The method permits the simultaneous estimation of 4-O-methyl-D-glucuronic acid, glucuronic and galacturonic acids.     

Separation of trimethylsilylated oximes of monosaccharides by capillary gas-liquid chromatography

Summary Trimethylsilylated oximes (TMS-oximes) of arabinose, fucose, galactose, glucose, mannose, rhamnose, xylose, glucuronic acid, and galacturonic acid were prepared using a two-step derivatization procedure. The TMS-oximes were separated and quantitated by gas-liquid chromatography using a 25-m fused-silica capillary column coated with crosslinked methylsilicone stationary phase. Starting with dried sugar extract, the entire procedure can be accomplished within 2 hours.     

Optimizing Dilute-Acid Pretreatment of Rapeseed Straw for Extraction of Hemicellulose

Biological conversion of biomass into fuels and chemicals requires hydrolysis of the polysaccharide fraction into monomeric sugars prior to fermentation. Hydrolysis can be performed enzymatically or with mineral acids. In this study, dilute sulfuric acid was used as a catalyst for the pretreatment of rapeseed straw. The purpose of this study is to optimize the pretreatment process in a 15-mL bomb tube reactor and investigate the effects of the acid concentration, temperature, and reaction time. These parameters influence hemicellulose removal and production of sugars (xylose, glucose, and arabinose) in the hydrolyzate as well as the formation of by-products (furfural, 5-hydroxymethylfurfural, and acetic acid). Statistical analysis was based on a model composition corresponding to a 3³ orthogonal factorial design and employed the response surface methodology to optimize the pretreatment conditions, aiming to attain maximum xylan, mannan, and galactan (XMG) extraction from hemicellulose of rapeseed straw. The obtained optimum conditions were: H₂SO₄ concentration of 1.76% and temperature of 152.6 °C with a reaction time of 21 min. Under these optimal conditions, 85.5% of the total sugar was recovered after acid hydrolysis (78.9% XMG and 6.6% glucan). The hydrolyzate contained 1.60 g/L glucose, 0.61 g/L arabinose, 10.49 g/L xylose, mannose, and galactose, 0.39 g/L cellobiose, 0.94 g/L fructose, 0.02 g/L 1,6-anhydro-glucose, 1.17 g/L formic acid, 2.94 g/L acetic acid, 0.04 g/L levulinic acid, 0.04 g/L 5-hydroxymethylfurfural, and 0.98 g/L furfural.     

Optimization of Brewery's spent grain dilute-acid hydrolysis for the production of pentose-rich culture media

Dilute-acid hydrolysis of brewery's spent grain to obtain a pentose-rich fermentable hydrolysate was investigated. The influence of operational conditions on polysaccharide hydrolysis was assessed by the combined severity parameter (CS) in the range of 1.39–3.06. When the CS increased, the pentose sugars concentration increased to a maximum at a CS of 1.94, whereas the maximum glucose concentration was obtained for a CS of 2.65. The concentrations of furfural, hydroxymethylfurfural (HMF), as well as formic and levulinic acids and total phenolic compounds increased with severity. Optimum hydrolysis conditions were found at a CS of 1.94 with >95% of feedstock pentose sugars recovered in the monomeric form, together with a low content of furfural, HMF, acetic and formic acids, and total phenolic compounds. This hydrolysate containing glucose, xylose, and arabinose (ratio 10∶67∶32) was further supplemented with inorganic salts and vitamins and readily fermented by the yeast Debaryomyces hansenii CCMI 941 without any previous detoxification stage. The yeast was able to consume all sugars furfural, HMF, and acetic acid with high biomass yield, 0.68C-mol/C-mol, and productivity, 0.92 g/(L·h). Detoxification with activated charcoal resulted in a similar biomass yield and a slight increase in the volumetric productivity (11%).     

LC-DAD-ESI-MS Characterization of Carbohydrates Using a New Labeling Reagent

A novel labeling reagent 1-(2-naphthyl)-3-methyl-5-pyrazolone (NMP) coupling to liquid chromatography with electrospray ionization mass spectrometry for the detection of carbohydrates from the derivatized rape bee pollen samples is reported. Carbohydrates are derivatized to their bis-NMP-labeled derivatives. Derivatives showed an intense protonated molecular ion at m/z [M+H]⁺ in positive-ion detection mode. The mass-to-charge ratios of characteristic fragment ions at m/z 473.0 could be used for the accurately qualitative analysis of carbohydrates. This characteristic fragment ion is from the cleavage of C2–C3 bond in carbohydrate chain giving the specific fragment ions at m/z [MH-C _m H_2m+1O _m -H₂O]⁺ for pentose, hexose and glyceraldehydes and at m/z [MH-C _m H_2m-1O _m+1-H₂O]⁺ for alduronic acids such as galacturonic acid and glucuronic acid (m = n ? 2, n is carbon number of carbohydrate). No interferences for all aliphatic and aromatic aldehydes presented in natural environmental samples were observed due to the highly specific parent mass-to-charge ratio and the characteristic fragment ions. The method, in conjunction with a gradient elution, offered a baseline resolution of carbohydrate derivatives on a reversed-phase Hypersil ODS-2 column. The carbohydrates such as mannose, galacturonic acid, glucuronic acid, rhamnose, glucose, galactose, xylose, arabinose and fucose can successfully be detected.     

Structural analysis of the gum polysaccharide from anacardium occidentale

The gum exudate from Anacardium occidentale contains galactose (61 %), arabinose (14 %), rhamnose (7 %), glucose (8 %) and glucuronic acid (5 %) in addition to small amounts (<2 %) of each of mannose, xylose and 4-0 methylglucuronic acid. Contrary to earlier findings, the main aldobiuronic acid present is 6-O-(β-D-glucopyranosyluronic acid)-D-galactose; smaller amounts of the 4-O-methyl analogue are also present. Mild acid hydrolysis showed only two galactobioses, 3-O-β-D-galactopyranosyl-D-galactose (major

component) and 6-O-β-D-galactopyranosyl-D-galactose (minor component). Degraded gum A, prepared by controlled acid hydrolysis, contained galactose, glucose, and uronic acid. A Smith-degradation of degraded gum A gave degraded gum B, which contained only galactose. Sequential Smith-degradations of Anacardium occidentale gum, and methylation analyses of the gum and of its degradation products indicated a highly-branched galactan framework consisting of chains of β-(1–3)-linked D-galactose residues branched and interspersed with β-(1–6) linkages. Arabinose is present as end-groups or in short (1–2)-linked chains up to five units long. Glucose, rhamnose, mannose xylose, and uronic acid are all present as end-groups.     

Characterisation of natural polysaccharides (plant gums) used as binding media for artistic and historic works by capillary zone electrophoresis

The monosaccharide constituents of plant gums were separated by capillary electrophoresis at pH 12.1 and detected with indirect UV absorbance. The plant gums investigated were gum arabic, gum acacia, gum tragacanth, cherry gum and locust bean gum (carob gum). The monosaccharides obtained after hydrolysis with 2M trifluoroacetic acid and lyophilisation of the hydrolysate were arabinose, galactose, mannose, rhamnose, xylose, fucose, and glucose, and the two sugar acids galacturonic and glucuronic acid, in accordance with the literature. They were separated in a background electrolyte consisting of NaOH to adjust the pH, 20 mM 2,6-pyridinedicarboxylic acid as chromophore for detection and 0.5 mM cetyltrimethylammonium bromide as additive to reverse the electroosmotic flow. Based on their electropherograms, the plant gums could be identified by their typical composition (depicted in a decision scheme) as follows: a peak of glucuronic acid, together with that of rhamnose, is indicative for gum arabic. Peaks of galacturonic acid and fucose point to gum tragacanth. Locust bean gum shows a major peak for mannose (with the concomitant galactose peak in ratio 4-1), whereas a glucuronic acid and a mannose peak together with a prominent arabinose peak indicates cherry gum. The method was applied to identify the plant gums in samples like watercolours and in several paint layers like gum tempera or those with egg white or drying oils as additives. Artificial aging experiments of thin layers of gum arabic on paper or glass carried out with UV-A radiation (366 nm) did not result in changes of the saccharide patterns, in contrast to the simultaneously conducted aging of a drying oil layer.     

柱前衍生化高效液相色谱法分析多糖中的单糖组成

报道了多糖中单糖组成的柱前衍生化高效液相色谱测定方法。采用反向高效液相色谱250nm紫外检测和使用梯度洗脱，6种还原单糖的1－苯基－3－甲基－5－吡唑啉酮衍生实现了良好的分离并具有良好的峰形。对单糖组成的定量测定进行了方法学考察，建立了单糖组成分析的数据分析方法，并用所建立方法对一个多糖中的单糖组成进行了分析，获得良好的重复性。     

A study of the products of the hydrolysis of the xylan ofMelilotus albus by endo-1 4-β-xylanase

The enzymatic hydrolysis of a 4-0-methylglucuronoxylan of white sweetclover (Melilotus albus) by a highly purified homogeneous endo-1, 4-β-xylanase fromAspergillus niger 14 has shown that the enzyme hydrolyzes 97% of the polysaccharide in 72 h. Acidic and neutral oligosaccharides were found in the hydrolysate after the action of the enzyme. An investigation of the hexauronic acid isolated has shown that the glucuronic acid is attached to the nonreducing end of the xylooligosaccharide, which demonstrates the specific action of the enzyme on the polysaccharide.     

黑海参多糖组成的研究

通过酶降解、酒精沉淀、DEAE柱纯化和脱色精制四步，从黑海参体壁中制得黑海参多糖的纯品。经电泳法及凝胶拉法鉴定，所得样品为均一组分，是一种典型的动物酸性杂多糖，内含硫酸酯基。样品经水解后用HPLC检测，得葡萄糖（36．7％）、岩藻糖（16．4％）、葡萄糖醛酸（34．2％）、木糖（7．22％）及一些未知成分（5．47％）。经Smith降解及一些波谱特征表明，单糖之间苷键是α-型，主要为1-2和1-3连结。凝胶往法测定其平均分子量约是96×104。     

Enhanced Xylose Recovery from Oil Palm Empty Fruit Bunch by Efficient Acid Hydrolysis

Oil palm empty fruit bunch (EFB) is abundantly available in Malaysia and it is a potential source of xylose for the production of high-value added products. This study aimed to optimize the hydrolysis of EFB using dilute sulfuric acid (H₂SO₄) and phosphoric acid (H₃PO₄) via response surface methodology for maximum xylose recovery. Hydrolysis was carried out in an autoclave. An optimum xylose yield of 91.2 % was obtained at 116 °C using 2.0 % (v/v) H₂SO₄, a solid/liquid ratio of 1:5 and a hydrolysis time of 20 min. A lower optimum xylose yield of 24.0 % was observed for dilute H₃PO₄ hydrolysis at 116 °C using 2.4 % (v/v) H₃PO₄, a solid/liquid ratio of 1:5 and a hydrolysis time of 20 min. The optimized hydrolysis conditions suggested that EFB hydrolysis by H₂SO₄ resulted in a higher xylose yield at a lower acid concentration as compared to H₃PO₄.