【作者】 吕明霞；

【导师】 崔同；

【作者基本信息】 河北农业大学 ， 农产品加工及贮藏工程， 2011， 硕士

【摘要】 多糖(Polysaccharides,简称PS)是由大量的单糖组成的大分子化合物,水果是多糖最主要的来源。研究表明,多糖具有增强机体免疫功能,抗肿瘤、抗病毒、抗衰老、降血脂、血糖作用、抑菌作用等,其生理活性与多糖的结构密切相关。目前水果中多糖的单糖组成分析方法有比色法和色谱法,前者的分析定量不准确,后者常用HPLC和GC或GC-MG的方法分析,由于HPLC的灵敏性较低,常用GC的方法分析多糖的结构。近年来GC的方法已经用于一些水果样品中多糖结构的分析,但这些结果只是分析了单一水果多糖的结构。针对这些不足,本项研究对GC的方法进行了较系统的开发、评价和大量实际样品分析试验。对多糖水解条件进行了研究,考察了硫酸的浓度、水解时间、料液比对多糖水解的影响,最后确定多糖水解的条件是2 mol/L硫酸,沸水浴水解3 h,料液比是1:100。对单糖的糖腈乙酰化衍生物的衍生条件进行了研究,考察了衍生剂的加入量和衍生时间对单糖衍生的影响,最后确定了单糖衍生的条件是90℃,样品10 mg,加入11 mg盐酸羟胺进行糖肟化40 min,0.5 mL吡啶为溶剂,冷却后,加入1 mL乙酸酐乙酰化10 min。开发了一种用于多糖中单糖组成分析的GC方法。色谱条件是色谱柱为KB-1毛细管柱(0.5μm×0.32 mm×30 m)。氮气流速1 mL/min;升温程序为:180℃保持8 min,10℃/min升至220℃保持3 min,再以10℃/min升至240℃保持3 min;进样量1μL。8种单糖鼠李糖、木糖、阿拉伯糖、岩藻糖、半乳糖醛酸、甘露糖、葡萄糖、半乳糖在20 min得到分离。方法最低检出限2-6μg,0.04-10 mg之间线性相关系数在0.9995-0.9999之间,回收率为90.1%-107.3%。采用酸水解-糖腈乙酰化衍生GC法对中国北方常见的15种水果(苹果、梨、葡萄、桃、杏、李子、柿子、枣、山楂、猕猴桃、草莓、桑椹、瓜类、香蕉和桔子)的33个品种的多糖(PS)含量进行了分析,结果表明这15种水果中总多糖(TPS)含量在0.08%(葡萄)-1.30%(猕猴桃)之间,其中水溶性多糖(SPS)占TPS的比例在17.7%(猕猴桃)-86.3%(桃)之间。不同水果之间PS的含量差异明显。采用糖腈乙酰化衍生GC法对中国北方常见的15种水果(苹果、梨、葡萄、桃、杏、李子、柿子、枣、山楂、猕猴桃、草莓、桑椹、瓜类、香蕉和桔子)的33个品种多糖的单糖组成进行了分析,结果表明这15种水果中半乳糖醛酸是水溶性多糖的主要成分,所占比例在6.8%(李子)到91.1%(山楂)之间。在不溶性多糖中除含有较高比例半乳糖醛酸(1.9% - 46.5%)之外,阿拉伯糖(1.8% - 38.0%)、半乳糖(8.3% - 56.0%)、木糖(3.0% - 30.9%)和岩藻糖(4.7% - 26.4%)也有相当含量,葡萄糖的比例在0.7%(桃)-54.6%(猕猴桃)之间,甘露糖和鼠李糖的比例在6%以下。不同水果多糖的单糖组成差异明显,李子、猕猴桃和香蕉的多糖中最具代表性的组分分别是半乳糖、葡萄糖和木糖。本研究采用重量法对木枣生长期、33个品种枣中糖类成分的变化进行分析,结果表明,木枣生长期糖类成分的变化:正常果的游离糖是逐渐增加,而粗多糖的含量是减少的;低聚糖的含量在白熟期减少后增加。裂果中的糖类物质是逐渐增加的。比较了22种枣品种与其物性的关系中,游离糖与硬度和弹性成显著关系,与胶粘性和咀嚼性成极显著关系;低聚糖与弹性成极显著,与硬度和咀嚼性成显著关系,与胶粘性无显著关系;粗多糖只与弹性成显著关系,与硬度、胶粘性和咀嚼性无显著关系。枣的33个品种中,游离糖的含量最多的是肉兜子枣(31.3%),最低的是雪枣(12.4%);低聚糖含量最多的是肉兜子枣(3.2%),最低的是蛤蟆枣(1.1%);粗多糖含量最多的是品种1(15.1%),最低的是晋矮4号(4.1%)。本试验建立的用于分析水果中多糖组成的硫酸水解-糖腈乙酰化衍生的GC法,具有操作简单准确灵敏的特点,不仅可以测出单糖的含量,而且可以提供单糖的比例,可用于枣、苹果、梨、桃、葡萄、山楂、草莓等大量水果的多糖组成进行分析。从实际样品分析结果可以看出,不同水果的SPS中半乳糖醛酸的含量及比例差异较大,而且SPS的含量及比例要高于IPS的含量及比例,因此水果是一种良好的SPS资源。用重量法分析测定的枣中的糖类成分为枣的深加工提供了参考,而且分析了枣中糖类成分与其硬度、弹性、胶粘性和咀嚼性的关系,揭示了枣果实的质地。更多还原

【Abstract】 Polysaccharide (Polysaccharides, as PS) is composed of a large number of single sugar molecule compound, the fruit is the main source of polysaccharides. Studies have shown that polysacchar ides with enhanced immune function, anti-tumor, anti-virus, anti-aging, blood fat, blood sugar, such as antimicrobial effect, its biological activity is closely related with the polysaccharide structure. The current structure of polysaccharides in fruit colorimetric and chromatographic methods, quantitative analysis of the former is not accurate, which is commonly used in HPLC and GC or GC-MG method of analysis, due to poor sensitivity of HPLC. The method commonly used in GC analysis of polysaccharides structure. GC methods have been used in recent years. Some fruit samples in the analysis of polysaccharide structure, but structure of a single fruit is the structure of polysaccharides. For these deficiencies, the study of the GC a more systematic approach to the development, evaluation and test a large number of real sample analysis.Polysaccharide hydrolysis conditions were studied to investigate the sulfuric acid concentration, hydrolysis time, solid to liquid ratio of polysaccharide hydrolysis, and finally had the conditions of hydrolying polysaccharide, which was 50 mg sample and 5 mL2 mol / L sulfuric acid , water bath for 3 h.On the acetylation of sugar derivatives of the sugar derivative conditions were studied to investigate the addition of derivatives and derivative agent time on the impact of a single sugar derivative, and finally determine the conditions derived monosaccharide 90℃, samples of 10 mg, 11 mg of hydroxylamine hydrochloride were added sugar oxime 40 min, 0.5 mL pyridine as the solvent, after cooling, add 1 mL of acetic anhydride acetylation 10 min.GC method for the analysis of monosaccharide composition in polysaccharides(PS)was developed. The PS were hydrolysis with 2 mol/L sulfuric acid at 100℃for 3 h, sugar oxime reaction at 90℃for 40 min, acetylation at 90℃for 10 min, and then GC analysis. A KB-1 column (0.5μm×0.32 mm×30 m) was used and the N2 flow rate was 1 ml / min. The temperature program was: 180℃for 8 min, in 10℃/min to 220℃(3 min), in 10℃/min to 240℃(3 min). The injection volume was 1μL. Rhamnose, xylose, arabinose, fucose, galacturonic acid, mannose, glucose, galactose were separated in 20 min. The lowest detection limit was 2-8μg, linear correlation coefficients was 0.9995-0.9999 between 0.04-10 mg and the recovery was 90.1%-107.3%.Experiments were done by sugar nitrile acetylation GC method on the contents of the non-digestible polysaccharides (NDPS) in fifteen common species of fruits in North China, including five apple varieties, five pear varieties, five peach varieties, three grape varieties and five melon varieties. The results of which showed that the proportion of total polysaccharide (TPS) in these fruits ranged from 0.08% (grape) to 1.3% (kiwi), among which water-soluble polysaccharide was between 17.7% (kiwi) and 86.3% (peach). Significant differences existed in contents of PS in terms of different species.Experiments were done by sugar nitrile acetylation GC method on the composition of polysaccharide in fifteen common species of fruits in North China, including five apple varieties, five pear varieties, five peach varieties, three grape varieties and five melon varieties. The results of which showed that galacturonic acid was the main constituent of water-soluble polysaccharide in the fifteen kinds of fruits, whose proportion ranged from 6.8% (plum) to 91.1% (hawthorn). In aspect of insoluble polysaccharide, it contained a high percentage of galacturonic acid, ranging from 1.9% to 46.5%, together with arabinose(1.8%-38.0%),galactose (8.3%-56.0%), xylose(3.0%- 30.9%) and fucose(4.7%-26.4%), which also contributed to considerable amount. Glucose was low in peach (0.7%) and high in kiwi (54.6%), mannose and rhamnose was below 6%. Significant differences existed in the composition of polysaccharide in terms of monosaccharide. The dominating monosaccharides in plum, kiwi and banana were galactose, glucose and xylose, respectively.The weight method was used to determine contents in the growth cycle, Jujube, 33 varieties and changes in sugar composition, the results showed that the carbohydrate composition of wood date growth cycle change was the normal result of the displaced sugar was gradually increased, The polysaccharide content was reduced; oligosaccharide content of the reduction in the increase of the white cooked. Cracking the carbohydrate material was gradually increased. Comparison of 22 kinds of jujube and its texture relations, displaced sugar and hardness and elasticity as a significant relationship with the adhesive and chewing into a significant relationship; oligosaccharides was a very significant into flexibility, and the hardness and chewiness showed significant relations, and the adhesive was not in significant relationship; polysaccharides was flexibility into the only significant relationship, and hardness, gumminess and chewiness was no significant relationship. The 33 Jujube varieties, the most abundant free sugar is the Roudouzi date (31.3%), the lowest was Xuezao (12.4%); the most oligosaccharide content was the Roudouzi date (3.2%), the lowest was Hama zao (1.1%); the most abundant polysaccharide was species 1 (15.1%) and lowest was the Jin ai 4 (4.1%).The test set used to analyze the composition of fruits and sulfuric acid hydrolysis of polysaccharides - sugar nitrile acetylated derivative GC method was simple and accurate and sensitive features, not only can measure the sugar content alone, but also provide the ratio of simple sugars that can be used the dates, apples, pears, peaches, grapes, hawthorn, strawberry and other fruits and a large number of polysaccharide composition analysis. From the actual sample analysis results can be seen in SPS of different fruit, content and ratio of galacturonic acid, which was quite different, and the SPS was higher than the proportion of the content and the content and the proportion of IPS, so fruit was a good resource for SPS. Carbohydrate in jujube were determined by weight, which provided refer for the jujube deep processing, and analysis of carbohydrate components the relationship with their hardness, elasticity, gumminess and chewiness, which revealed the texture of jujube fruit.更多还原