【作者】 崔茉丽；

【导师】 王振宇；

【作者基本信息】 哈尔滨工业大学 ， 食品科学， 2010， 硕士

【摘要】 茶树菇(Agrocybe cylindracea)是一种集保健食疗于一身的天然食用菌。研究表明,茶树菇不仅含有各种人体必需的氨基酸,还含有丰富的B族维生素和多种矿物质,具有抗氧化、治疗高血压的作用。近年来还发现茶树菇含有增强人体免疫、抗癌能力的活性物质。本文以茶树菇子实体为原料,对其核苷酸分离提取工艺、体外抗氧化及抗辐射活性进行了研究。采用超声波辅助提取核苷酸,利用正交实验优化提取工艺,得到茶树菇核苷酸的最佳提取条件为:超声功率140 W,超声时间25 min,液料比30:1,水浴时间2.0h,核苷酸得率为4.80 %。采用微波辅助提取核苷酸,响应面分析法优化提取工艺,得到茶树菇核苷酸的最佳提取条件为:微波功率495W,微波时间7min,液料比18:1,水浴浸提时间2.0h,核苷酸得率为4.53 %。采用研磨珠辅助提取核苷酸,响应面分析法优化提取工艺,得到茶树菇核苷酸的最佳提取条件为:研磨时间为12 min ,液料比为51:1,研磨珠装载量为12.5 %,核苷酸得率为6.94 %。以核苷酸得率为指标,对几种提取工艺进行比较,可知研磨珠法辅助提取核苷酸得率最高。对茶树菇核苷酸进行总还原力、清除羟基自由基(·OH)能力、清除超氧阴离子(·O2-)能力等抗氧化指标进行研究。结果发现,茶树菇核苷酸具有较强的抗氧化活性。建立由紫外辐射引起脂质过氧化损伤模型,进行茶树菇核苷酸抗脂质过氧化能力的研究,结果发现茶树菇核苷酸对由紫外辐射引起脂质过氧化有较强的抑制作用。在此基础上,以结肠癌细胞HT-29为载体,建立体外辐射模型,研究茶树菇核苷酸的体外抗辐射能力。结果表明茶树菇核苷酸有一定的辐射防护功能。同时还发现茶树菇核苷酸与辐射伤害对HT-29的抑制具有协同作用。针对茶树菇这些特点,选取几种常见的食用菌:茶花菇、金钱菇、山元菇、鸡腿菇、榛蘑提取核苷酸,进行总还原能力及清除ABTS自由清除能力、抗辐射功能的研究。结果表明食用菌核苷酸均具有一定的抗氧化活性及抗辐射功能,其中茶树菇活性最强。更多还原

【Abstract】 Agrocybe Chaxingu (Agrocybe cylindracea) is a crude edible fungi. It has both health-care and treatment function, so it is often called the healthy food. A. cylindracea not only contains most of essential amino acids, plenty of Vitamin B and many mineral substances, also has anti-oxidation effect and treatment function of hypertension. In recent years, many researchers also found that the A. cylindracea has some components which can enhance the immune function of human body so as to prevent cancer. This paper used the fruiting bodies of A. cylindracea as the raw material to study the extraction technology of nucleotides, in vitro antioxidant and anti-radiation activities.By ultrasonic wave-assisted extraction method and the orthogonal experimental design, the paper has got the optimum parameter of extraction processing for nucleotides from A. cylindracea nucleotides: ultrasonic power 140W, ultrasonic time 25 min, liquid to solid ratio 30:1, and extracting time in water 2.0 h. The yield of the nucleotide can reach about 4.80 % under this improved condition.By the microwave-assisted extraction method and the response surface methodology, the paper got the optimum parameter of extraction processing for nucleotides from A. cylindracea: microwave power 495 W, microwave time 7 min, liquid-solid ratio 18:1, extracting time in water 2.0 h. The yield of the nucleotide can reach about 4.53% under this improved condition.By the grinding beads-assisted extraction method and the response surface methodology, the paper got the optimum parameter of extraction processing for nucleotides from A. cylindracea: grinding time 12 min, liquid-solid ratio 51:1, loading capacity of grinding bead 12.5 %. The yield of the nucleotide can reach about 6.94 % under this improved condition.The paper also studied on anti-oxidative capacity, including total reducing power, scavenging hydroxyl radical (·OH) capacity, removing superoxide anions (·O2-) capacity and anti-lipid peroxidation of lecithin of A. cylindracea nucleotides. The results showed that A. cylindracea nucleotides had a strong antioxidant activity.The paper investigated the antiradiation effect of A. cylindracea nucleotides using HT-29 cells as the carrier to establish an in vitro radiation model. The results showed that A. cylindracea nucleotides had a certain effect of radiation protection. It was also found that A. cylindracea nucleotides and radiation had a synergistic effect on proliferation inhibitory of HT-29 cells.Through extracting nucleotides from several common edible fungus, including A. cylindracea, L. giganteus, C. acervata, P. serotinus, C. comatus and A. mellea, then determining their total reducing power, scavenging ability of ABTS and anti-radiation effect. Results showed that all these nucleotides of edible fungi had some certain antioxidant activity and anti-radiation function. And these activities of A. cylindracea are more stronger than others.更多还原