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果胶类多糖的研究进展 总被引:25,自引:1,他引:25
果胶类多糖是植物细胞壁多糖类家族中结构最为复杂的一种,具有优良的胶凝性和乳化性及多种生理功效。详细介绍了果胶类多糖在结构、化学组成及其应用等方面的研究进展。 相似文献
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采用酸(柠檬酸)、碱(氢氧化钠)、酶(多聚半乳糖醛酸水解酶)3种方法从马铃薯渣中提取果胶多糖,研究不同提取方法对多糖得率、单糖组成、酯化度、分子质量及分子链构象的影响。结果表明:3种提取方法得到的马铃薯渣果胶多糖均以富含半乳糖侧链的鼠李半乳糖醛酸聚糖I(RG-I)结构为主。其中,碱提果胶多糖得率最高(23.1%),其次为酸提(11.7%)和酶提(6.0%)。3种果胶多糖甲酯化度均较低(0~7.5%),而乙酰化度较高,且酸提和酶提马铃薯渣果胶多糖的乙酰化度高于碱提(分别为13.6%,10.7%,6.6%)。分子质量分析结果表明,酶提果胶多糖的分子质量最高(1 706.3 ku),且分布最窄。通过Mark-Houwink-Sakurada方程判断:酶提果胶多糖的分子链形态较为聚集,接近球状构象;酸提果胶多糖介于球状和线团状构象之间;碱提果胶多糖分子链形态最为疏松,呈无规线团状构象。 相似文献
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用水、质量分数0.5%草酸铵溶液、0.05 mol/L HCl溶液、1 mol/L KOH溶液从苹果皮中提取得到4种果胶多糖,分别是水溶性果胶多糖(WSP)、盐溶性果胶多糖(CSP)、酸溶性果胶多糖(ASP)和碱溶性果胶多糖(BSP)。测定了它们的总糖、糖醛酸和蛋白含量以及相对分子质量、单糖组成及摩尔比和红外光谱;并初步研究了4种苹果皮果胶多糖对人结肠腺癌细胞系HT-29细胞生长的抑制作用。结果显示:WSP、CSP、ASP和BSP的相对分子质量均大于4.0×105Da;气相色谱测定WSP、CSP、ASP和BSP的单糖组成及摩尔比,4种果胶多糖均含有半乳糖,而CSP所含的半乳糖醛酸含量最多,BSP不含半乳糖醛酸。WSP、CSP、ASP和BSP都能抑制人结肠腺癌细胞系HT-29细胞的增值,CSP的抑制活性最高(35.65%),BSP的抑制活性最低(10.30%),初步分析可能与苹果皮果胶多糖中半乳糖及半乳糖醛酸残基的含量相关。 相似文献
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《食品与发酵工业》2017,(12):150-156
以马铃薯渣为原料,采用酶法脱除淀粉和蛋白质,分别以盐酸法、柠檬酸法、碱性磷酸盐法和复合盐法从马铃薯渣中提取果胶,经超滤、乙醇沉淀和冷冻干燥得到4种马铃薯果胶多糖。研究不同的提取方法对马铃薯果胶多糖提取率、组成特性的影响。结果表明,碱性磷酸盐法和复合盐法提取果胶得率高(分别为29.89%和21.01%)、半乳糖醛酸含量高(分别为29.71%和31.57%)。碱性磷酸盐法提取果胶的中灰分含量(22.38%)显著高于其他3种果胶多糖(2.09%~2.48%)。4种工艺提取得马铃薯果胶是低甲氧基果胶;蛋白质含量低于3.0%,没有显著差异;中性单糖组成主要包括半乳糖,及少量的阿拉伯糖、鼠李糖和葡萄糖。马铃薯果胶多糖的峰值分子质量在1.65×10~4~1.17×10~6u左右,为非均一多糖,4种方法提取得马铃薯果胶均具有果胶的特征官能团。 相似文献
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以超声波辅助酶法提取及纯化紫薯果胶类多糖,并对其主要成分及稳定性进行分析。结果表明:所得紫薯果胶类多糖的干燥减量、酸不溶灰分、pH值、总半乳糖醛酸、酯化度、总糖、蛋白质含量分别为4.32%、0.32%、4.22、65.24%、31%、65%、1.02%,符合相关标准。测出所得紫薯果胶类多糖的重均分子量为70745 Da和968 Da。乳酸饮料稳定性试验中,紫薯果胶类多糖添加量为0.20%时,所得发酵乳酸饮料的沉淀率最低,口感好;紫薯果胶类多糖的添加量为0.25%时,稳定性R值最大,且变化小。 相似文献
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提取方法对马铃薯渣果胶结构特征及特性的影响 总被引:1,自引:0,他引:1
对酸处理提取(acid-treated extraction,ATE)、酶处理提取(enzyme-treated extraction,ETE)和盐沉析提取(salt-treated extraction,STE)的马铃薯渣果胶抗氧化活性及其特性进行研究,发现3种提取方法中,STE果胶提取率最高。流变特性结果显示,ATE果胶具有最高的初始黏度。结构特征表明,STE多糖呈光滑致密的块状结构;ETE果胶呈不规则褶皱的形状;ATE多糖呈棉絮片状,较其他2种其表面结构松软。3种多糖的单糖组成各不相同,ATE的果胶主要由葡萄糖、半乳糖、阿拉伯糖以及少量的鼠李糖和木糖组成;ETE的果胶主要的单糖组成为葡萄糖和半乳糖;STE的果胶主要的单糖组成为葡萄糖、半乳糖、阿拉伯糖。ATE果胶(51481 Da)分子质量最大,其次为ETE果胶(14593 Da)、STE果胶(11669 Da)。抗氧化特性显示,ATE果胶表现出较高的清除DPPH自由基的能力,STE具有较高的清除·OH和·O2-的能力。 相似文献
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The popular beverage ingredients Cassia obtusifolia and Cassia tora were found to have considerable amounts of water-soluble polysaccharides (WSPs) (58.5 and 55.9/100 g of dried extract). The composition, characteristics, and in-vitro physiological effects of these polysaccharides and their possible health benefits were investigated. The major polysaccharide components in the WSP of C. obtusifolia were possibly pectic polysaccharides and hemicellulose, while C. tora WSP was mainly composed of arabinoglucan and pectic polysaccharides. These WSPs had inhibitory effects on the activities of α-amylase and pancreatic lipase, while they rendered an increase in protease activity. These WSPs also had the ability to bind bile acids and reduce the amount of cholesterol available for absorption. This suggested that these WSPs had potential application as herbal ingredients in beverages. Further investigations on their in-vivo hypocholesterolaemic effects and intestinal functions using animal-feeding experiments are under way. 相似文献
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ANA JIMÉNEZ RAFAEL GUILLÉN JUAN FERNÁNDEZ-BOLAÑOS ANTONIA HEREDIA 《Journal of food science》1994,59(6):1192-1196
Cell walls of olives (Olea europaea L.), Hojiblanca and Manzanilla, were isolated and fractionated into polysaccharides, and compositions compared. Pectic and hemicellulosic fractions were purified by ion exchange and gel filtration chromatography, and neutral sugar and uronic acid composition determined. Differences occurred between cultivars and seasons: Manzanilla had higher pectic polysaccharides and lower xylans. Hojiblanca showed similar but lesser differences. Arabinans were the main neutral pectic polysaccharides with arabinose > 80%. Homogalacturonans and rhamnogalacturonans were > 50% of the acidic pectic fractions. Degree of esterification and molecular weights were related to extracting solvent. Xyloglucans and galactoglucomannans were neutral hemicelluloses with molecular weights ? 260 kD. Glucuronoarabinoxylans had higher molecular weights (up to 400 kD). Acidic xylans were important in the pulp. 相似文献
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Black olives of Taggiasca (Ta) and Conservolea (Co) varieties were processed according to the Greek style method in order to investigate the effect of this type of table olive processing on cell wall composition. Naturally black processing involves the storage in brine of fully ripe olives for several months, allowing a spontaneous fermentation by a mixed flora followed by fermentation by the lactic acid bacteria and yeasts. The smaller fruits of Ta variety are richer in pectic polysaccharides, accounting for half of total cell wall polysaccharides (12 mg/fruit), whereas in Co they accounted for one third (23 mg/fruit). Fresh Co olives had higher proportion of glucuronoxylans and xyloglucans (33%), whereas these polysaccharides accounted for 22% in Ta. The processing did not cause significant variations in the cell wall polysaccharide composition of Ta fruits, although pectic polysaccharides became more soluble in aqueous solutions. Conversely, processed Co olives had slightly higher amounts of galacturonan-rich pectic polysaccharides than the unprocessed fruits, suggesting that the long stage in brine might have contributed to the stabilisation and/or the biosynthesis of new polysaccharides. The changes caused by processing on cell wall polysaccharides appear to be closely related to the activity and availability of cell wall degrading enzymes. 相似文献
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Physical and chemical changes in developing strawberry fruits 总被引:3,自引:0,他引:3
J R Woodward 《Journal of the science of food and agriculture》1972,23(4):465-473
Strawberry fruits of thevariety Red Gauntlet were harvested at 7 day intervals after petal fall. Changes in fruit weight, percentages survival on the plant, chlorophyll: carotenoid and anthocyanin, titratable acid, pH of extracts and sugar content were measured. Also changes in soluble and total pectic polysaccharides in alcoholinsoluble residues of harvested fruits were followed during development. Fruit growth was not exponential and in later stages of growth the falling survival rate was correlated to fruit softening. Net synthesis of chlorophyll and carotenoid pigments took place up to 28 days and anthocyanin synthesis commenced 28 to 35 days after petal fall. The sugar content of berries increased with time and titratable acid concentrations increased slightly during development, falling in ripening fruits. The specific viscosity of soluble pectic polysaccharides fell from 28 days after petal fall. There was net synthesis of polyuronide but not neutral polysaccharide during the development of fruits and the amount of insoluble pectic polysaccharide became small and relatively constant compared with the amount of soluble polysaccharide by 21 days after petal fall. Fruits undergoing senescence lost almost all their insoluble pectic polysaccharides. The developmental processes taking place in growing fruits, especially with respect to changes in cell wall structure, and the relevance of results to fruit storage are discussed. 相似文献
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E Sch?pplein H Dietrich K Wucherpfennig 《Zeitschrift für Lebensmittel-Untersuchung und -Forschung》1991,193(1):1-8
Depending on the preparation method, the colloid content of raspberry juices treated with pectolytic enzymes, can be up to 2.5 g/L. Analysis of the polysaccharides shows that there are in particular, arabinans, arabinogalactans type II and rhamnogalacturonans. While the content of arabinans could be reduced by the action of arabinases, the arabinogalactans and rhamnogalacturonans were not degraded by conventional pectic enzymes. Besides these cell-wall polysaccharides, it was possible to isolate a high molecular-mass beta-glucan, which is thought to originate from Botrytis cinerea. Technical problems in juice clarification or filtration may be caused by this beta-glucan or the high content of residual pectic substances. 相似文献
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Roasting induced change to carbohydrates and cell wall polysaccharides was investigated in three varieties of cocoa beans. The concentrations of glucose and fructose decreased after roasting but levels of the non-reducing sugars, sucrose, raffinose, stachyose and verbascose, were not markedly affected. Approximately 10% of the arabinose content of the polysaccharides was degraded but, overall, the pectic and hemicellulosic polymers remained intact after roasting. The degree of esterification and acetylation of the pectic polysaccharides were unaffected by roasting. Roasting did promote an interaction between polysaccharides, proteins, polyphenolics and Maillard products. This led to the formation of insoluble complexes which co-purified with, and augmented, the levels of cell wall material isolated from roasted compared to unroasted beans. The implications of the results are discussed in relation to the role that “Klason lignin” plays in the formation of these chemical amalgams during roasting. 相似文献
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Victoria V. Golovchenko Daria S. Khramova Raisa G. Ovodova Alexandre S. Shashkov Yury S. Ovodov 《Food chemistry》2012
The polysaccharide fraction extracted with simulated gastric juice from onion bulbs contained a mixture of galactan with short-length sugar chains, pectic polysaccharides and evident content of proteinaceous material. Galacturonan and rhamnogalacturonan were the main constituents of the linear regions of the sugar chains of the pectic polysaccharides. The ramified regions included rhamnogalacturonan-I. NMR data revealed that the side chains of the ramified region contained mainly 1,4-linked β-d-galactopyranose residues and lesser content of 1,3-linked β-d-galactopyranose and 1,5-linked α-l-arabinofuranose residues. Furthermore, the proteinaceous material was determined to be partly linked to the sugar chains. 相似文献
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Barry J. H. Stevens Robert R. Selvendran 《Journal of the science of food and agriculture》1980,31(12):1257-1267
Cell wall material (CWM) was isolated from the wet ball-milled alcohol-insoluble residue of cabbage by treatment with Pronase, phenol-acetic acid-water and 90% aqueous dimethyl sulphoxide to remove precipitated proteins, starch and other intracellular compounds. Some solubilisation (mainly of pectic material) occurred during the purification stages. Methylation analysis of the cold water-soluble polysaccharides showed that the main neutral glycosidic linkages in descending order of concentration, were: non-reducing terminal arabinose groups, 5-linked arabinose and 4-linked galactose. The CWM contained a high level of arabinose-containing pectic polysaccharides. The main linkages present in the non-cellulosic polysaccharides were 4-linked galacturonic acid, non-reducing terminal arabinose groups and 5-linked arabinose; doubly branched arabinose residues were also present. Sequential extraction of the CWM by aqueous inorganic solvents yielded further information on the types of polysaccharides present. The general structural features of the CWM are discussed in the light of these results. 相似文献