Functional properties of water-soluble non-starch polysaccharides from rice and ragi: Effect on dough characteristics and baking quality

Water-soluble non-starch polysaccharides (NSP) were isolated from native and malted rice and ragi. The effects of addition of water-soluble NSP on dough rheological characteristics and baking quality were investigated. Water-soluble NSP had low relative viscosity and showed no gelling activity despite considerable amount of ferulic acid (∼492.5-528.0 μg/g). However, they were found to stabilize protein foams against thermal disruption. Addition of water-soluble NSP (0.25 and 0.50%) to wheat flour resulted in increased water absorption and decreased dough development time. However, prolonged mixing resulted in slightly lower dough stability. Increase in dough extensibility and improvement in starch pasting characteristics were observed upon the addition of water-soluble NSP. Significant increase in loaf volume and softness of the bread was also observed. Water-soluble NSP both from malted rice and ragi had higher effect compared to the native one. Results showed that water-soluble NSP can be added to various low-fiber food preparations with positive dough functionality.     

Structural characteristics of water-soluble feruloyl arabinoxylans from rice (Oryza sativa) and ragi (finger millet, Eleusine coracana): Variations upon malting

Water-soluble feruloyl arabinoxylans (feraxans), isolated from native and malted (96 h) rice (Oryza sativa) and ragi (Eleusine coracana) grains, were fractionated on DEAE-cellulose, followed by purification on Sephacryl S-300 and the homogeneity was ascertained by high performance size exclusion chromatography, cellulose acetate and capillary electrophoresis. Structural characterization of the purified polysaccharides by methylation, followed by GLC–MS, and also by ¹H NMR and ¹³C NMR spectroscopy, indicated very high branching and presence of high amounts of O-2 substituted xylans. The amount of O-2, 3 disubstituted xylopyranosyl residues and the arabinose:xylose ratio was higher in malt feraxans. All feraxan samples consumed almost equal amounts of periodate (4.02–4.30 μmol/mg). High amount of xylose (∼40%), as identified by Smith degradation, further substantiated the high branching of feraxans. A model is presented depicting the structure of water-soluble feraxans from rice and ragi and their changes upon malting.     

Studies on the free sugars,water-soluble gums and hemicelluloses from barley grains and malts

The free sugars, water-soluble gums, and hemicelluloses have been isolated from four barley grain samples [Hordeum vulgare (L.)], and from their commercial malts. Arabinose, xylose, galactose, glucose, fructose, maltose and sucrose occur as free sugars in the grains and the proportions of these sugars increase on malting. Mannose also occurs as a free sugar in the malts. The water-soluble gums contain arabinose, xylose, lesser amounts of mannose and galactose, and varying amounts of glucose. The aqueous-ethanol supernatants from the hot-water extracts are glucans of low molecular weight. The hemicellulose A polymers contain arabinose, xylose, mannose and glucose. Wide variations in the mannose and glucose contents were observed in these polysaccharides. The hemicellulose B polymers are arabinoxylans, containing lesser amounts of galactose and glucose. The aqueous-ethanol supernatants from the hemicellulose B precipitations contain arabinose, xylose, mannose, galactose and glucose. These polysaccharides differ markedly from those present in the aqueous-ethanol supernatants of the hot-water extracts. All polysaccharides are modified to varying degrees during malting.     

Fractionation of wheat bran carbohydrates

A procedure for the fractionation of wheat bran carbohydrates with an emphasis on non-starchy polysaccharides is described. After a complete extraction using a chloroform-methanol (2:1) solvent, bran was destarched using amyloglucosidase and extracted using ammonium oxalate. Then delignification by sodium chlorite followed by hot water extractions was applied. Small quantities of water-soluble hemicellulosic polymers containing glucose, xylose, arabinose with lesser amounts of galactose and mannose were removed by these three steps. The remaining holocellulose (of a low protein content) was extracted using 1M sodium hydroxide, and hemicelluloses A1 and B1 were separated from the extract. Hemicellulose A1 (5.4% of native bran) was determined to be a xylan containing smaller proportions of arabinose and glucose, whereas hemicellulose B1 (12.6% of native bran) was a complex mixture of several types of polysaccharides, the major one being a highly branched arabinoxylan. Hemicelluloses A4 and B4, obtained by 4M sodium hydroxide extraction of the residue after 1M sodium hydroxide treatment, had lesser amounts of arabinose compared with the respective fractions from the preceding step. For hexoses, higher proportions of mannose and glucose were found. α-Cellulose residue retains 19.8% of pentosans.     

Free sugars and non-starch polysaccharide contents of good and poor malting varieties of wheat and their malts

The yield and composition of low molecular weight sugars and non-starch polysaccharides (NSP) of a good- and a poor-malting variety of wheat and their malts were determined. There were seven, four and six-fold increases in total sugars, sucrose and maltose, respectively, on 120 h germination in both varieties, the increase being higher in the good-malting variety than in the poor-malting variety. The poor-malting variety contained slightly (11.7%) higher levels of total NSP than the good-malting variety (10.9%). The uronic acid formed 2.5 to 23.3% of the different NSP fractions, the highest being in EDTA-extractable (EDTAE) fractions. The hexose content of the cold water-soluble fraction decreased from 63.4 to 20% on malting in the good-malting variety but its content remained the same in the poor-malting variety. Mannose was detected only in the EDTAE fraction of the good-malting variety and its concentration decreased from 24.2 to 4.6% on malting. Malt samples from both varieties contained slightly higher levels of hemicellulose A, hemicellulose B and cellulosic fractions, and lower levels of EDTAE NSP fractions. The water-soluble fraction was 45% of the total NSP of the good-malting variety and 28% of the poor-malting variety.     

Degradation of cereal bran polysaccharide-phenolic acid complexes by Aspergillus niger CFR 1105

Cereal brans such as wheat and rice are abundant sources for obtaining bioactive phenolic compounds such as ferulic and coumaric acids, in turn these can be bio-transformed into high value flavour compounds such as vanillin. Aspergillus niger CFR 1105, found to induce greater amounts of cell wall degrading enzymes, was inoculated into wheat and rice brans, and grown for 24, 48, 72 and 96 h to understand the degradation pattern of non-starch polysaccharides and phenolic acid complexes. Native wheat bran polysaccharides mainly consisted of arabinose, xylose, galactose, and glucose, in % of 27:39:2:30, with traces of mannose, whereas rice bran consisted of arabinose, xylose, galactose, and glucose in % of 9:27:31:32, respectively. Both the cereal bran arabinoxylans were degraded extensively by A. niger at 96 h, whereas the degradation of 1,3/1,4-β-d-glucans and cellulose was negligible. Bound phenolic acids of rice and wheat brans identified by HPLC were found to be mainly ferulic, coumaric, syringic acids in % of 93.6:6.3:0 (wheat), 34.7:55.8:9.5 (rice) and were drastically degraded/utilized at 96 h. The above results have indicated preferential degradation of arabinoxylans of wheat bran by A. niger, which can be exploited to obtain bioactive compounds such as ferulic acid.     

气相色谱法分析豌豆粉渣中多糖的单糖组分

采用糖醇衍生化方法,运用气相色谱分析测定豌豆粉渣中多糖的单糖组分及各单糖的相对组成比例。结果表明：经水洗处理的豌豆粉渣中各单糖的相对组成质量比为鼠李糖∶阿拉伯糖∶木糖∶葡萄糖∶半乳糖=1.00∶92.00∶39.50∶21.80∶12.30;未经水洗处理的豌豆粉渣中各单糖的相对组成质量比为鼠李糖∶阿拉伯糖∶木糖∶葡萄糖∶半乳糖=1.00∶68.86∶38.43∶25.00∶9.57。豌豆粉渣中多糖主要由阿拉伯糖和木糖组成,其中阿拉伯糖的相对含量为23.78%。     

Structure of pectin in relation to abnormal hardness after cooking in pre-peeled, cool-stored potatoes

Unacceptable hard tissue can be detected in pre-peeled potatoes after cooking. Pectin methyl esterase (PME) has been suspected to facilitate formation of Ca-bridges between pectin molecules by deesterification of the uronic acids. But this has also been questioned, due to the low storage temperature of the peeled tubers, optimum of PME being 50-70 °C. Hardness in tubers was induced by several packaging methods. Annual and seasonal variations were observed. In the work, analysis of nonstarch polysaccharides (NSP) are considered representative of the pectin content. Analyses revealed an increase in insoluble NSP during storage after peeling and cooking, and a decrease in branching (arabinose, galactose) and degree of methyl esterification of total NSP, in both fresh and cooked tissue, dependant on storage period. Reduction of steric hindrance by debranching of the pectin molecules as well as a PME-induced increase of possible Ca-cross-linking sites may favor hardening of the tissue. The microscopy does not show any pectin changes until after cooking, but the chemical data do. This suggests that hardening, at least partly, is due to the removal of methyl ester groups, as well as galactose and arabinose in the side chains. The Ca-bridges can probably not be formed until sufficient calcium is released from the starch during gelatination.     

Nonstarch Polysaccharide Fractions of Raw, Processed and Cooked Carrots

The total and soluble nonstarch polysaccharide (NSP) components of raw, processed (canned and frozen) and home-cooked (boiled) Royal Chantenay carrots have been analyzed. NSP fractions were characterized by separation and summation of the monosaccharides resulting from acid hydrolysis of the parent polysaccharides. Total NSP was primarily composed of glucose, ?37%, and uronic acid, ?35%, containing polysaccharides. Soluble NSP was composed of >50% uronic acids. Processing and simulated home-cooking of raw carrots resulted in an increase in the amount of NSP/unit dry weight. Relative to raw carrots, cooking of canned product resulted in the largest (～twofold) increase in total and soluble NSP/unit dry weight. Relative differences in NSP were not as great when compared on a wet weight basis.     

Consistency,Polysaccharidase Activities and Non-Starch Polysaccharides Content of Soya Beans During Tempe Fermentation

The relation between consistency of soya beans, polysaccharidase activities and the non-starch polysaccharides (NSP) content of soya beans was investigated during tempe fermentation. The fermentations were carried out in a rotating drum reactor (RDR) as well as in the traditional stationary tempe process. The firmness of the soya beans decreased rapidly during the first day of incubation. At increased incubation temperatures the hardness of the beans decreased more rapidly. In the RDR glycosidase activities became significantly higher beyond 48 h of incubation compared with the traditional process. This might have resulted from (a) the better control of temperature and gas composition in the RDR, and/or (b) the agitation in the RDR. The content of arabinose, galactose and uronic acids in the water-unextractable solids of NSP decreased more rapidly than that of glucose, mannose, xylose and fucose. These results indicate that during enzymatic maceration of soya beans in tempe fermentation, the arabinogalactan and pectin fractions are preferentially solubilised. © 1997 SCI.     

The carbohydrate composition of cotyledons and hulls of cultivars of Lupinus angustifolius from Western Australia

The hulls and cotyledons from three Western Australian cultivars (Gungurru, Yorrel and Danja) of Lupinus angustifolius, all of low alkaloid content, were analysed separately for their carbohydrate content and composition. Only minor differences in composition between these three cultivars were observed. More notably, the cotyledons of all the cultivars contained levels of non-starch polysaccharides (NSP), ranging from 290 to 310 g kg^?1 dry weight considerably higher than had been measured previously in cultivars of this species. Galactose, arabinose and uronic acid residues accounted for approximately 67%, 13% and 10%, respectively, of the cotyledon NSP. Although only a small proportion of the cotyledon NSP is soluble, a much larger proportion could be extracted with hot EDTA treatment. The oligosaccharide content of the cotyledons ranged from 74 to 80 g kg^?1 dry weight. Cotyledons had very low contents of cellulose, lignin and starch. Hulls consisted predominantly of NSP, with values ranging from 856 to 891 g kg^?1 dry weight. Glucose, xylose, uronic acids and arabinose were the principal sugar residues present reflecting the compositions of the major constituent polysaccharides, cellulose, hemicelluloses and pectins. Only low levels of lignin were measured in hulls. Cotyledon NSP and hulls from these cultivars may have considerable value as sources of dietary fibre in the human diet.     

Gluconacetobacter hansenii UAC09-mediated transformation of polyphenols and pectin of coffee cherry husk extract

Gluconacetobacter, a bacterial cellulose (BC)-producing organism, has ability to utilise pectin and phenolic compounds. The extract of coffee cherry husk (CCH), a high pectin- and polyphenol-containing agro waste was used in the study. Production of endo- and exo-polygalacturonase, polyphenol oxidase and tannase was observed during fermentation. Co-utilisation of glucose and galacturonic acid was observed. Accumulation of rhamnose, arabinose and galactose indicated the breakdown of pectin. Among the phenolic acids, benzoic acid derivatives were found to be degraded faster than cinnamic acid derivatives. Degradation of tannic acid was more pronounced among the bound forms than free forms in the culture broth. In BC, accumulation of free tannic, gentisic and coumaric acids was observed during the 2nd week of fermentation. The present work indicates the ability of the organism to produce BC by the utilisation of agro waste like CCH.     

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。     

钝顶螺旋藻多糖的分离纯化及组成分析

目的：对钝顶螺旋藻多糖进行提取、分离纯化和热降解,并对不同多糖组分的基本化学性质和糖链的精细组成进行分析。方法：采用蛋白酶酶解、醇沉、阴离子交换色谱法和热降解,从钝顶螺旋藻中提取和分离纯化出P0、P0.2、P0.4、P0.6、P0.8五种多糖组分及其热降解产物。采用高效凝胶排阻色谱法、离子色谱法、1-苯基-3-甲基-5-吡唑啉酮柱前衍生-高效液相色谱法和亲水液相色谱-高分辨傅里叶转换质谱（hydrophilic interaction liquid chromatography-Fourier transform mass spectrometry,HILIC-FTMS）联用技术,分析比较不同多糖组分的化学性质和糖链精确组成。结果：钝顶螺旋藻多糖中P0、P0.2、P0.4和P0.6组分硫酸根质量分数在6%～7%,而P0.8组分硫酸根质量分数最高（14.46%）。单糖组成分析结果说明,P0组分是1 种葡聚糖,P0.2组分是主要由葡萄糖、半乳糖、鼠李糖、岩藻糖等中性糖组成的杂多糖;而P0.4、P0.6和P0.8组分主要是由鼠李糖、葡萄糖醛酸、葡萄糖、木糖和半乳糖组成的结构非常复杂的硫酸鼠李聚糖。采用HILIC-FTMS分析多糖组分热降解产物中的寡糖组成,发现P0.2糖链主要是由己糖单糖、戊糖二糖、脱氧己糖-戊糖寡糖、脱氧己糖-糖醛酸的寡糖片段组成,硫酸根在脱氧己糖、戊糖和己糖上,糖链组成复杂。而P0.4和P0.6组成相似,主要鼠李糖-戊糖寡糖、鼠李糖-葡萄糖醛酸寡糖、戊糖二糖和三糖寡糖片段组成,硫酸根连接在鼠李糖和戊糖上。结论：钝顶螺旋藻中有多种不同结构的复杂硫酸多糖,其中葡萄糖醛酸-鼠李聚糖是钝顶螺旋藻中特有的一种硫酸多糖。     

The phenolic acid and polysaccharide composition of cell walls of bran layers of mature wheat (Triticum aestivum L. cv. Avalon) grains

The purpose of this study was to examine the carbohydrate and phenolic‐ester composition of cell walls in wheat bran layers. Four defined layers of wheat bran were separated manually from mature grains of wheat (Triticum aestivum L. cv. Avalon) to give samples of beeswing bran (outer pericarp), cross cells, testa + nucellar epidermis and aleurone cells. The cell‐wall material from each layer, and from a sample of intact bran, was analysed for carbohydrates and wall‐bound esterified phenolic acids. The cell‐wall material of intact bran was rich in arabinose and xylose with significant quantities of glucose and uronic acid and a relatively small amount of galactose and mannose. The varying ratios of arabinose:xylose in cell walls of isolated bran layers indicated that the heteroxylans had tissue‐specific substitution patterns. HPLC analysis of phenolic acids identified significant amounts of esterified ferulic acid and 8‐8′‐ (aryltetralin form), 5‐8′‐, 5‐5′‐, 8‐0‐4′‐ and 5‐8′‐(benzofuran form)‐dehydrodiferulic acids in the isolated cell walls. Ferulic acid was highly concentrated in the aleurone layer, whereas dehydrodiferulates were concentrated in the beeswing bran and cross cells. The role of phenolic cross‐linking is discussed in relation to the architecture of the cell walls of wheat bran and to processing implications. Copyright © 2005 Society of Chemical Industry     

Preliminary studies on the mucilages extracted from Okra fruits,Taro tubers,Jew's mellow leaves and Fenugreek seeds

Okra fruits, Taro tubers, Jew's mellow leaves and Fenugreek seeds are commonly used in Egypt to prepare popular diets with desired slimy consistency.The mucilages were extracted and preliminary studies conducted to characterise them physically. The pH values of a 1% solution of the mucilages varied from 6·9-7·5 for Okra and Taro, 7·1–7·8 for Jew's mellow, and 5·9-6 for Fenugreek, depending upon extraction conditions. The highest viscosity was observed in Okra solutions, followed by Fenugreek, Jew's mellow and Taro mucilages. Okra and Jew's mellow mucilages are acidic polysaccharides which contain higher amounts of ash than the Taro and Fenugreek mucilages which are neutral polysaccharides. All mucilages are associated with protein. Gel chromatography indicated strong interaction of protein with the polysaccharide. The acid hydrolysis of the mucilages followed by paper chromatography revealed that all mucilages contain methyl pentose, glucose, galactose, and fructose, in different proportions. Taro and Fenugreek mucilages are free of rhamnose. All mucilages are devoid of arabinose and mannose except Fenugreek which contained these two sugars.     

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.     

Resistant starch from differently processed rice and ragi (finger millet)

 Resistant starch (RS) formed during parboiling, expanding, popping, flaking, roller drying, extrusion cooking, malting and autoclaving of rice and ragi was determined. The processing conditions were chosen to represent the limits that are being used commercially. RS formation was more pronounced in autoclaving and a drastic increase (∼fivefold) in its content was observed during repeated autoclaving (heating and cooling) was observed. Though processed ragi samples contained more nitrogen, protein and dietary fibre, the RS content was very low compared to rice. Hot paste viscosity studies showed the extruded and malted samples to have low peak and set-back viscosities. Determination of the percentage of starch gelatinization revealed that powdered samples showed 100% gelatinization at higher temperatures whereas malted and extruded samples showed the same at low temperatures.     

龙眼、枸杞和红枣多糖的理化性质及其协同益生活性

为了比较龙眼多糖（LP）、枸杞多糖（GP）和红枣多糖（JP）的理化特性及其益生活性差异,探究其是否具有协同增效作用,本文分析了三种多糖的基本成分、分子量分布、单糖组成、显微结构、溶解性、粒径、溶液电位等理化特性,以及三种多糖单独作用或复合作用对益生菌增殖的影响。结果表明LP、GP和JP主要含有中性糖、少量糖醛酸和蛋白质,其中中性糖含量分别为86.25%、72.36%、82.98%;LP和JP的Mw分别是70.73 ku、185.93 ku;GP的Mw为120.61 ku、4.53 ku;LP和GP主要由阿拉伯糖、葡萄糖、半乳糖组成,其摩尔比分别为22.49:56.81:10.18和16.84:62.05:11.08,JP主要由阿拉伯糖、葡萄糖、半乳糖醛酸组成,其摩尔比为10.63:70.05:10.88;三种多糖的微观结构有较大差异,LP为碎片化聚集体,GP呈片状,JP为网状结构;三种多糖的粒径、粒度分散系数、溶液电位均不同;三种多糖均能显著促进益生菌增殖,并呈现剂量依赖效应,在浓度为30 mg/mL时,三者的益生活性为JP>GP>LP;当LP、GP和JP以质量比2:3:1复配时,其益生活性最强,且远好于相同浓度下三种多糖单独作用的益生效果。由此表明,龙眼、枸杞和红枣三种多糖复配后,对益生菌的增殖具有协同增效作用。     

Non-starch polysaccharides from sunflower (Helianthus annuus) meal and palm kernel (Elaeis guineenis) meal—preparation of cell wall material and extraction of polysaccharide fractions

Two different chemical methods, sequential extraction with alkali and sodium chlorite and treatment with 4-methylmorpholine N-oxide (MMNO), were applied to the extraction of non-starch polysaccharides (NSP) from the enzymically deproteinated, water-insoluble cell wall materials of sunflower (Helianthus annuus L) meal and palm kernel (Elaeis guineensis Jacq) meal. The NSP content accounted for 550 g kg^?1 (sunflower meal) and 750 g kg^?1 (palm kernel meal) of the cell wall materials. Neither of the treatments alone was capable of solubilising more than about half of the original NSP. Combined treatment using alkali/chlorite followed by MMNO completely dissolved cell wall material from palm kernel meal, whereas a small residue (40 g kg^?1 of original NSP) was left in sunflower meal. Loss of NSP occurred with both methods (total NSP recovery ranging from 88% for alkali/chlorite extraction of sunflower to 64% for MMNO extraction of palm kernel). Due to differences in solubility revealed upon acidification and/or dialysis, extracts became subdivided into precipitates and soulble fractions. The sugar composition of the resulting fractions enabled a tentative identification of teh major non-starch polysaccharides; sunflower meal was found to contain cellulose, (acidic) xylans, polyuronide-containing fractions and xyloglucan; palm kernel meal was found to contain mannans, cellulose and xylans, with the major part of the mannans originating from the endosperm and the xylans being almost exclusively located in the endocarp.