【作者】 杨锋；

【导师】 段玉峰；

【作者基本信息】 陕西师范大学 ， 食品科学， 2004， 硕士

【摘要】 火棘（Pyracantha fortuneana（Maxim．）Li），又叫赤阳子、救军粮，主要分布于我国东南和西南部。其果实、叶和根都可药用，果实具有健脾消积、活血止血等功能。同时也可食用，酸甜适口、香气浓郁，含有丰富的营养物质。因此作为药食两用的火棘具有很大的开发价值。 为了进一步开发火棘野生资源，本论文对秦巴山区产火棘果实中水溶性多糖的提取、分离纯化、理化性质、生物活性、膳食纤维的制备及特性等方面进行了较为深入的研究，取得了如下的研究结果。 火棘水溶性多糖的最佳提取工艺为：90℃水，提取9小时，料液比为1：10；在此条件下火棘多糖的提取率约为3.5％；超声波处理可使火棘多糖的得率提高30％以上。 采用DPPH·分光光度法对火棘粗多糖进行体外抗氧化试验，结果表明火棘粗多糖具有明显的清除DPPH·作用，SC₅₀为1.87mg／mL。 经试验，蛋白酶-Sevag法具有较好的脱蛋白效果；LSA-8大孔吸附树脂可以用于火棘粗多糖的脱色；再经DE-52和Sephadex G-200柱层析分离得到PP-A2、PP-A3、PP-B2三种多糖组分。 气相色谱、红外光谱、理化特性分析结果表明PP-A2和PP-B2是同一物质，主要由阿拉伯糖和鼠李糖组成，其中还含有少量的果糖、半乳糖和甘露糖，阿拉伯糖：鼠李糖：果糖：半乳糖：甘露糖=5.05：4.51：3.37：1.88：1，经Sephadex G-200柱层析测定其分子量为30，000Dal，不同的是PP-B2中含有少量多酚类色素物质。PP-A3是一种糖蛋白，分子量为210，000Dal，主要由阿拉伯糖组成，其中含有少量的葡萄糖和果糖，阿拉伯糖：葡萄糖：果糖=1.62：1：1.59，其中氨基酸总含量为0.5％（半胱氨酸未检出）。 火棘多糖作为膳食纤维类功能性食品添加剂，具有较好的膨胀力、持水力及阳离子交换能力，同时具有较好的清除自由基能力，其作为面条改良剂时的最适使用量为3％左右。更多还原

【Abstract】 Abstract Pyracantha fortuneana (Maxim.) Li, which was also named Chiyangzi and Jiujunliang, is mainly distributed in the southeast and southwest of China. Its fruit, leaf and root all could be used as medicine in China. Furthermore,its fruit was edible, which contained abundant nutriment. So Pyracantha fortuneana (Maxim.) Li fruit had great exploitation value.In order to ulteriorly exploit Pyracantha fortuneana (Maxim.) Li resource, the author conducted a series of study on the water-soluble polysaccharide from Pyracantha fortuneana and achieved the following results.The optimal extraction technology of Pyracantha fortuneana polysaccharides were 90℃, 9h, 10:1 (WAV) of water to its fruit. Extraction ratio of the polysaccharides was about 3.5%. With ultrasonic, extraction ratio can be increased more than 30%.Through antioxidant in vio experiment by DPPH . spectrophotophy, it showed that Pyracantha fortuneana crude polysaccharide could remove DPPH . and its effect was very prominent and SC50 was 1.87mg/mL.Some experiments indicated that the protein could be almost clearly removed from Pyracantha fortuneana crude polysaccharide by protein-enzyme-Sevag and decolor could be achieved by LSA-8 big size adsorption resin. Then isolated by DE-52 and Sephadex G-200 gel filtration, three glycoconjugates PP-A2,PP-A3 and PP-B2 were attained.Gas chromatography analysis, infra-red spectra analysis and physical and chemical characters showed that PP-A2 and PP-B2 were the same materials. They mainly contained rhamnose, arabinose, fructose, galactose and mannose in a ratio of 5.05:4.51:3.37:1.18:1. Sephadex G-200 gel filtration analysis showed that their molecular weight was 30,000dal. Different to PP-A2, PP-B2 contained a little pigment. PP-A3 was a kind of glycoprotein. It was composed of arabinose, glucose and fructose in a ratio of 1.62:1:1.59 and some amino acids whose total content was 0.5%. In amino acid, cysteine was not detected out. The molecular weight of PP-A3 was 210,000dal.As dietary fiber functional food additivies, Pyracantha fortuneana polysaccharide has good expansibility, ability to keep water and ability to exchange with positive ion. Furthermore, it can scavenge free radical. When it is used as meliorative additive in noodle, the dosage of Pyracantha fortuneana polysaccharide is about 3%.更多还原