香薷多糖的乙醇分级纯化及其性质

采用热水浸提法从香薷中得到多糖提取物,然后采用乙醇分级沉淀法纯化香薷多糖,收集得到乙醇体积分数为20%、30%、40%、50%、60%、70% 条件下析出的多糖沉淀物。之后经Sevag 法脱除多糖中的游离蛋白,得到纯化后的6 个香薷多糖组分HMP-1、HMP-2、HMP-3、HMP-4、HMP-5 和HMP-6。应用紫外和红外光谱检测HMP-1、HMP-2、HMP-3、HMP-4、HMP-5 和HMP-6 的光谱性质,测定糖含量、可溶性蛋白质含量和糖醛酸含量,并用气相色谱法测定单糖组成。结果表明：HMP-1、HMP-2、HMP-3、HMP-4、HMP-5和HMP-6 均为酸性多糖,蛋白含量较高。HMP-1 和HMP-2 主要含有阿拉伯糖和葡萄糖,HMP-3 主要含有阿拉伯糖、葡萄糖、半乳糖和核糖,HMP-4 主要含有阿拉伯糖、葡萄糖和半乳糖,HMP-5 和HMP-6 主要含有阿拉伯糖、葡萄糖、半乳糖和甘露糖。此外,6 个多糖组分均含有少量的鼠李糖、木糖,但单糖间物质的量比相差较大。     

Sugar Composition of Cucumber Cell Walls During Fruit Development

The sugar composition of pickling cucumber cell walls was analyzed in seven cucumber sizes. Relative to total cell wall sugars, glucose did not change, while the other major neutral sugars, galactose, xylose and mannose, underwent relatively small declines during fruit development. The ratios of galacturonic acid/rhamnose and galacturonic acid/arabinose showed large increases during fruit growth, which indicated that pectin structure may change. Pectin methylation in the mesocarp tissue increased from 35 to 64% as cucumber fruit matured. A positive correlation was observed between the firmness of cucumber mesocarp tissue and the total amount of cell wall sugars in the fresh tissue. Cucumber peel tissue contained 4 to 5-fold higher sugar concentrations than either the mesocarp or endocarp tissues.     

Separation and quantification of component monosaccharides of the tea polysaccharides from Gynostemma pentaphyllum by HPLC with indirect UV detection

A reversed-phase high-performance liquid chromatographic (HPLC) method is described for the simultaneous determination of aldoses and uronic acids. The separation was carried out on a RP-C₁₈ column (4.6 mm i.d. × 250 mm, 5 μm, Venusil, USA) using precolumn derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP) and UV detection at 250 nm, and the 10 PMP derivatives of mannose, ribose, rhamnose, glucuronic acid, galacturonic acid, glucose, xylose, galactose, arabinose and fucose were baseline separated within 40 min. Furthermore, the described method was applied to the quantitative analysis of component monosaccharides in the water-soluble polysaccharides extracted from Gynostemma pentaphyllum Makino tea and the result showed that the tea polysaccharide was a typical heteropolysaccharide and consisted of mannose, ribose, rhamnose, glucuronic acid, galacturonic acid, glucose, xylose, galactose and arabinose in the molar contents of 16.3, 10.3, 47.1, 5.6, 24.0, 128.4, 25.0, 101.4 and 71.1 μM, respectively. Quantitative recoveries of the component monosaccharides in the tea polysaccharide were in the range of 94.6–108.0% and the RSD values were lower than 4.9%. The results demonstrated that the proposed HPLC method was precise and practical for the analysis of the G. pentaphyllum tea polysaccharide.     

鹰嘴豆非淀粉多糖的分离纯化及结构表征

提取鹰嘴豆中的粗多糖,通过酶处理和Sevag法除去多糖中的淀粉和蛋白质,经DEAE-52纤维素柱和Sephadex G-75凝胶柱分离纯化分别得到鹰嘴豆非淀粉中性多糖和酸性多糖,并通过紫外光谱、气相色谱、红外光谱、扫描电镜测定其性质和单糖组成。结果表明：鹰嘴豆非淀粉多糖在260 nm和280 nm波长处均无吸收峰,表明两种多糖均不含核酸、蛋白质以及肽类等;气相色谱测定表明鹰嘴豆非淀粉中性多糖单糖组成的物质的量比为鼠李糖∶岩藻糖∶阿拉伯糖∶木糖∶甘露糖∶半乳糖∶葡萄糖=2.48∶1∶3.92∶0.87∶32.82∶18.79∶28.06,鹰嘴豆非淀粉酸性多糖单糖组成物质的量比为鼠李糖∶岩藻糖∶阿拉伯糖∶木糖∶甘露糖∶半乳糖∶葡萄糖=2.22∶1∶3.92∶2.10∶5.92∶15.99∶8.57（均以岩藻糖为标准）;红外光谱测定表明二者均有多糖的特征吸收峰;扫描电镜显示鹰嘴豆非淀粉中性多糖呈线形结构而鹰嘴豆非淀粉酸性多糖呈卷曲的片状结构。     

衍生化气相色谱法测定亚麻胶的单糖组成

目的采用衍生化气相色谱法(GC)测定亚麻胶的单糖组成。方法从亚麻粕中提取纯化得亚麻胶,经酸水解、衍生化后,用气相色谱分析。结果亚麻胶样品中鼠李糖、阿拉伯糖、岩藻糖、木糖、甘露糖、葡萄糖和半乳糖的质量分数分别为12.13%,6.83%,4.30%,12.70%,3.75%,10.15%,15.30%。结论亚麻胶主要由鼠李糖、阿拉伯糖、岩藻糖、木糖、甘露糖、葡萄糖和半乳糖7种单糖组成,以半乳糖含量最高。     

Sugar profile of extracellular polysaccharides from different Tremella species

Heteropolysaccharides isolated from liquid cultures of Tremella species were derivatised to alditol acetates and identified by GLC against derivatised sugar standards. From the sugar profiles it was evident that all of the polysaccharides contained essentially the same sugars but in different ratios. Some of the polysaccharides contained the five carbon sugars-fucose, ribose, xylose and arabinose together with six carbon sugars-mannose, galactose and glucose. The uronic acid content of Tremella heteropolysaccharides also varied according to species. In addition, carbon source (arabinose, xylose, glucose, fructose and galactose) affected the sugar (including uronic acid content) ratio within the polysaccharides.     

Composition of Dietary Fiber: Neutral and Acidic Sugar Composition of the Alcohol Insoluble Residue from Human Foods

The alcohol insoluble residue (AIR) isolated from 12 foods was acid hydrolyzed and analyzed for neutral and acidic sugars. Aliquots taken at 1 hr were reduced, acetylated and analyzed for neutral sugar content with GLC. Glucose from cellulose, starch and non-cellulosic polysaccharides was analyzed with colorimetric methods. The predominant sugars present in the dietary fiber were arabinose, xylose, galactose, glucose and uronic acids. Pectin and hemicellulose together comprised the majority of cell wall polysaccharides. Samples high in starch generally contained the greatest amounts of dietary fiber and the least amount of water on a fresh plant basis.     

Changes in the ethanol-insoluble material of tea leaves (Camellia sinensis L.) during maturation

The ethanol-insoluble material (e.i.m.) of immature and mature tea leaves was fractionated into hot-water-soluble polysaccharides and proteins, ammonium oxalate-soluble pectic acid, hemicelluloses A and B and α-cellulose, by successive extraction with hot water, ammonium oxalate, sodium hypochlorite and cold alkali. The final residue was termed α-cellulose. The hot-water extract and the hot-water-insoluble residue were found to contain appreciable quantities of protein nitrogen. Each fraction was hydrolysed and the mixture of sugars was separated on paper chromatograms and estimated. It appeared that each stage of the extraction procedure removed from the e.i.m. a complex mixture of polysaccharides. The sugars produced on hydrolysis of the arbitrary fractions from immature and mature leaves were qualitatively similar, although there were quantitative differences and were glucose, galactose, xylose, arabinose, rhamnose, galacturonic acid and an unidentified uronic acid. Maturation was mainly accompanied by an increase in the content of lignin, hemicelluloses and α-cellulose.     

高效阴离子交换色谱法分析杜氏盐藻多糖的单糖组成

选用CarboPacPA20分析柱(3mmi.d.×150mm),以H2O-250mmol/LNaOH-1mol/LNaAc为流动相,建立了三元梯度洗脱分离、积分脉冲安培检测多糖中常见的8种中性单糖和2种糖醛酸的高效阴离子交换色谱分析方法;利用离子交换色谱柱(DEAESepharoseCL6Bfastflow,3.5cm×30cm)和凝胶过滤色谱柱(SepharoseCL6B,2.6cm×100cm)从提取出β-胡萝卜素的杜氏盐藻残渣中分离出PD1、PD2、PD3、PD4a和PD4b共5个多糖级分,选用适当的条件水解后,利用高效阴离子交换色谱法测定了各多糖级分的单糖组成。其中具有显著生物活性的多糖级分PD4a中主要含有半乳糖、阿拉伯糖、木糖、葡萄糖、盐藻糖及鼠李糖6种中性糖,还含有少量糖醛酸;PD4b中主要含有核糖、葡萄糖、半乳糖、阿拉伯糖及木糖5种中性糖,不含糖醛酸。该结果与PMP柱前衍生化反相高效液相色谱法测定的单糖摩尔比基本一致。10种单糖的离子色谱法的检出限为0.76～2.92nmol/L(以3倍信噪比计),峰面积相对标淮偏差RSD为0.72%～3.25%。     

ALCOHOL-INSOLUBLE CONSTITUENTS OF JUICE VESICLES OF CITRUS FRUIT

SUMMARY– The texture of the edible portion of citrus fruit is determined by the characteristics of the juice vesicles and their insoluble constituents. Alcohol-insoluble solids (AIS) of the juice vesicles of several varieties of oranges, grapefruit and tangerines were studied at different stages of maturity. The protein content of the AIS as determined by the Kjeldahl method was found to decrease with fruit maturity, although total amount per fruit tended to increase. Polysaccharides were separated by extracting the AIS with alkali of various concentrations. Each fraction after hydrolysis was analyzed for the monomers both by paper chromatography and gas chromatography of the silylated derivatives. Galactose, arabinose and traces of glucose were found in fractions associated with galacturonic acid, and xylose, arabinose and glucose in different proportions were found in the hemicellulose and cellulose fractions. Traces of rhamnose and other uronic acids also were detected.     

Purification,preliminary structural characterization and in vitro antioxidant activity of polysaccharides from Acanthus ilicifolius

Crude Acanthus ilicifolius (A. ilicifolius) polysaccharides (CAIP) were obtained by hot water extraction and deproteinated. Two major polysaccharide fractions, the neutral A. ilicifolius polysaccharide (NAIP) and the acid A. ilicifolius polysaccharide B (AAIP-B), were isolated from CAIP by chromatography using DEAE-Sepharose Fast Flow and Sepharose CL-6B. The molecular weights (M_w) of NAIP and AAIP-B, determined by high performance gel-filtration chromatography (HPGFC), were 11,775 and 23,161 Da, respectively. AAIP-B contained 51.23% uronic acid, characteristic of a pectin-type hetero-polysaccharide. Analysis of the neutral monosaccharide composition indicated that NAIP contained high proportions of arabinose, galactose and glucose. However, AAIP-B was mainly composed of rhamnose, arabinose and galactose. Their structure properties were confirmed by FT-IR.     

沙蒿籽胶多糖的分级纯化和结构分析

采用0.1mol/L的氢氧化钾对沙蒿籽胶多糖进行组分分级得到水溶多糖(AG1)和水不溶多糖(AG2)。利用离子交换柱层析从AG1中分离得到酸性多糖(AG11)和中性多糖(AG12)。经凝胶过滤色谱检测,AG11和AG12为均一组分。化学组成分析表明,AG1为葡萄糖糖基组成的葡聚糖,并含有糖醛酸;AG11和AG12分别为阿拉伯糖、鼠李糖、木糖、甘露糖、葡萄糖和半乳糖等糖基组成的杂多糖,并含有糖醛酸,相对分子质量分别为8.63×105Da和3.46×105Da。红外光谱测定表明,AG11、AG12和AG2具有多糖的特征吸收,并且其糖环均为吡喃环。     

Fractionation and characterisation ofj water-soluble polysaccharide-protein complexes containing hydroxyproline from the leaves of Vida faba

The water-soluble polysaccharide-protein complexes obtained previously by extraction with aqueous trichloroacetic acid and by phenol-aqueous (pH 8) partitioning from the leaves of Vicia faba were fractionated into a number of components by continuous high voltage electrophoresis at pH 8.3 and 3.97 and by Sepharose 4B chromatography. The results indicated that these materials contained a spectrum of molecules with rather similar properties. All fractions obtained contained about 4–7% (wlw)lightly bound protein, two-thirds of which was made up of four amino acids: hydroxyproline, alanine, serine and threonine. Similarly, all materials contained uronic acid (10–70%; w/w)and neutral sugars (10–90%; w/w), mainly arabinose and galactose. High uronic acid content was found to be associated with appreciable rhamnose content and an arabinose-galactose ratio close to 2. This ratio became about 0.3 when the amount of uronic acids decreased to about 10% (w/w).     

Non-starch polysaccharides of canola meal: Quantification,digestibility in poultry and potential benefit of dietary enzyme supplementation

The non-starch polysaccharide (NSP) content as determined by gas chromatography (component neutral sugars) and colorimetry (uronic acids) was shown to be 16–22% in ten different samples of defatted canola (low glucosinolate rapeseed) seed. The non-cellulosic components of NSP accounted for 13–16% of the meal and on average consisted of arabinose (33%), xylose (13%), galactose (13%), glucose (5%), mannose (3%), rhamnose (2%), fucose (2%) and uronic acids (30%). Yellow-seeded and brown-seeded samples of canola contained similar contents of total dietary fibre although the composition of the fibre components tended to differ with the former showing a low content of lignin and associated polyphenols and a high content of NSP as compared with the latter type. NDF values tended to be lower for yellow-seeded than for brown-seeded canola due to the relatively high content of NSP in neutral detergent solubles of yellow-seeded canola. An initial balance study with laying hens showed low (<3%) digestibility of the polysaccharide components, and further studies were conducted with a commercial enzyme preparation (SP249, Novo Laboratories Ltd, Lachine, Quebec) to enhance the in-vivo hydrolysis of the NSP fraction of the meal. Laying hens were fed a semipurified diet containing 40% commercial canola meal with and without enzyme (1%). NSP digestibility was increased to 37% by the enzyme supplementation.     

The digestion of monosaccharide residues of the cell walls of oat and vetch hays by rumen contents in vitro

The extent and pattern of digestion of oat hay (Avena sativa L.) and vetch hay (Vicia sativa L.) monosaccharides by rumen contents was studied in vitro. The ratios of matrix polysaccharides to lignin were 1.25:1 and 3.82:1 in the vetch and oat hays, respectively. Glucose, xylose and uronic acids were the main sugars in both plants, comprising about 90% of the total monosaccharides. Glucose, xylose and arabinose were mainly confined to the cell walls (CW), whereas galactose and uronic acids were found in high proportions in the soluble fraction. Vetch had a particularly high uronic acid content (14.4 g 100 g^?1 DM), of which 71% was pectic material. The ratios of CW-glucose to CW-xylose were 2.23:1 and 3.74:1 in the oat CW and vetch CW, respectively. Based on monosaccharide analyses of the CW material, it is suggested that the degree of branching of the matrix polysaccharides is about twice as high in vetch as in oat hay. Total glucose and xylose were more digestible in oat than in vetch hay, whereas most of the minor sugars and the total uronic acids were more digestible in the vetch. Irrespective of species, CW glucose was more digestible than CW xylose. The digestibilities of CW glucose, CW xylose and CW uronic acid were: 61.0, 55.3, 51.5, 34.3 and 62.7, 42.6 for the oat hay and vetch hay, respectively. Following the pattern of digestion, CW arabinose and CW glucose were digested faster than CW xylose and CW uronic acid, irrespective of plant species. The extent of digestion at 12 h of incubation of these sugars was higher in vetch than in oat hay. It is suggeted that the concentration ratio of rapidly to slowly degradable CW sugars, in a given plant, is a major determinant of the rate of CW digestion by rumen microorganisms.     

卷烟中非挥发性有机酸、糖类、某些氨基酸和磷酸的同时测定

以山梨醇作内标,羟胺吡啶和BSTFA 1%TMCS为衍生化剂,采用GC法同时测定了国内外21种牌号卷烟中的木糖、阿拉伯糖、鼠李糖、果糖、甘露糖、半乳糖、葡萄糖、蔗糖、麦芽糖、天门冬氨酸、天门冬酰胺、丙二醇、丙三醇、乳酸、丙二酸、苹果酸、柠檬酸和磷酸。结果显示:①丙二醇和阿拉伯糖的RSD>10%,乳酸、天门冬酰胺、鼠李糖、半乳糖和麦芽糖的RSD>5%,其它成分的RSD<5%;②除丙二酸、半乳糖、鼠李糖、丙三醇和阿拉伯糖的回收率介于70%~75%外,其它组分的回收率>80%;③在所分析的卷烟样品中,进口混合型卷烟中柠檬酸、天门冬氨酸、天门冬酰胺、丙二醇和丙三醇含量较国产烤烟型卷烟的高,而糖类的含量则普遍较低,其它成分差别不大。     

Grape Pomace as a Potential Food Fiber

Grape pomace, and insoluble and soluble dietary fiber (DF) fractions, obtained by enzymatic-gravimetric methods, were analyzed for neutral sugars, uranic acids, Klason lignin and amino acids. DF constituted 80% of dry matter, IDF was the major fraction. The main neutral sugar constituent of IDF was glucose. The major part was cellulose and the remainder, along with xylose, was a xyloglucan, which also contained fucose. Uranic acids accounted for 64% of SDF and a high amount of arabinose, galactose and mannose were also included in that fraction. Proteins were not well solubilized by the assay enzymes. During the isolation of DF fractions a considerable solubilization of polyphenols was observed. These compounds were associated with Klason lignin in the starting material. Composition of DF fractions enables grape pomace to be considered a useful fiber-rich food ingredient.     

Fractionation and partial characterization of non-pectic polysaccharides from yellow mustard mucilage

A polysaccharide fraction was isolated from yellow mustard mucilage using pectinase hydrolysis and ammonium sulphate precipitation. Results indicated that ammonium sulphate precipitation produced a material with more glucose and less uronic acid compared to ethanol precipitation. Chemical, structural and rheological properties of the isolated fraction were investigated. Chemical analysis revealed that this material was mainly composed of glucose (61.1%); however, other sugars were also found, including galactose (13.8%), rhamnose (4.5%), mannose (13.1%) and xylose (7.5%). It also contained 6.9% of uronic acid. Methylation analysis indicated that this polysaccharide fraction consisted mainly of a β-1,4 linked glucosyl backbone. Rheological tests showed that the polysaccharide exhibited strong shear-thinning flow behaviour and weak gel structure. When the aqueous weak gel solution was subjected to an acid environment, the gel structure became stronger compared to more neutral conditions. This polysaccharide exhibited thermal stability over the temperature range from 5 to 90 °C.     

Extraction and composition of pectins and hemicelluloses of cell walls of sugar beet roots grown in Morocco

Summary Cell-wall polysaccharides were isolated as alcohol-insoluble residues (AIR) from Moroccan sugar beet slices at two stages of the harvest season (early and late samples). Pectins and hemicelluloses were extracted by a sequential treatment with water, EDTA, hot dilute hydrochloric acid, cold dilute sodium hydroxide, cold 1 M and 4 M sodium hydroxide and finally water at pH 7. The highest extraction yields were obtained for the dilute acid and alkali treatments, which extracted pectins rich in arabinose. The extracts from the late sample were rich in glucose which, was not retained on DEAE Sepharose CL 6 B, and which may come from microbial growth on the fields after harvesting. Yields for hemicelluloses after extraction with 1 M NaOH were 12% and 13% of AIR, respectively, for early and late beet slices, and after extraction with 4 M NaOH 5% and 6%, respectively. The extracts were rich in arabinose, xylose and glucose, and contained fucose and mannose. Fractionation on DEAE Sepharose gave one major non-retained fraction rich in neutral sugars, corresponding to xyloglucans and a minor retained fraction corresponding to heteroxylans, and residual pectins. Washing with water at pH 7 extracted pectins rich in rhamnose and galactose.     

海带中褐藻糖胶的组成分析

对海带中褐藻糖胶进行了紫外薄层色谱、气相色谱、氨基酸分析等方面的研究.结果表明褐藻糖胶是由鼠李糖、岩藻糖、木糖、甘露糖、半乳糖、葡萄糖、葡萄糖醛酸、硫酸根及蛋白质构成的复合物.其中单糖的摩尔比为RhaFUcXylManGalGlU=0.411.723.750.9612.17.褐藻糖胶的葡萄糖醛酸、硫酸根及蛋白质的含量分别为6.2%、8.7%和4.1%.