【作者】 冯毅斌；

【导师】 吴祖建； 姚一建；

【作者基本信息】 福建农林大学 ， 微生物学， 2011， 硕士

【摘要】 蛹虫草是一种具有多种生物学活性的食药用真菌,目前对蛹虫草的研究多集中在固体栽培中子实体产量的提高、液体发酵中虫草素含量的提高以及子实体或者菌丝体浸提液药理方面的研究等领域,而对基础营养物质对蛹虫草子实体生长以及有效成分合成与积累的影响研究很少。根据蛹虫草正常生长最基础的营养需求:底料、碳源、氮源、矿物元素,通过优化组合筛选出了10种培养基,按照同一培养条件进行人工栽培。实验得出2号培养基和5号培养基有利于提高子实体产量。添加4号氮源的培养基比添加1号氮源的培养基更有利于提高子实体产量。分析比较了虫草多糖的两种常用检测方法:苯酚-硫酸法和蒽酮-硫酸法。试验发现蒽酮-硫酸法更为精确。进一步对蒽酮-硫酸法做了改进,改进的蒽酮-硫酸法不仅大大减少了实验误差,而且显色物质在4h后仍然稳定。以蛹虫草子实体为原料,对影响多糖提取的条件进行了研究。以影响多糖产率的四大因素提取温度、提取时间、提取次数、固液比设计正交实验最终确定蛹虫草多糖提取的最佳工艺条件为:40倍水提取两次,每次在100℃下提取2h。蛹虫草有效成分提取、检测后发现4号培养基最有利于虫草多糖在子实体中积累,多糖产率达到15.25%。3号培养基最有利于甘露醇在子实体中积累,甘露醇产率达到7.00%。1号培养基有利于抗氧化物质的积累,粗提物对邻苯三酚自氧化的抑制率达到62.12%。综合以上四项分析,10号培养基对提高蛹虫草子实体内外品质最为有利。更多还原

【Abstract】 Cordyceps militaris (L.) Link. is an edible and medicinal fungus bearing various biological activities. Great efforts have been devoted to improve the output of fruiting bodies by solid culture, to improve the contents of cordycepin in liquid fermention and to explore the medicinal efficacy of extracts from both fruiting bodies and mycelium of Cordyceps militaris, while little attention has been paid to the study of how the basic nutrients influence the fruiting body growth and the synthesis and accumulation of bioactive metabolites of Cordyceps militaris.Ten culture mediums were prepared according to the basic nutritional requirements of main substrate ingredient, carbon sources, nitrogen sources and mineral elements and tested in the same condition. The results showed that Medium 2 and Medium 5 are propitious to improve the output of fruiting bodies of Cordyceps militaris. The medium adding Nitrogen Source 4 is more beneficial to improve the output of fruiting bodies than that adding Nitrogen Source 1.Two commonly used methods to detect polysaccharides were compared. The anthrone method was proved to be more accurate than the phenol-sulphuric acid method. The anthrone method has been modified. The color reaction of the modified anthrone method was still stable after four hours; furthermore, the system error was greatly reduced.The extraction condition of polysaccharides was studied using fruiting bodies of Cordyceps militaris. An orthogonal experiment was employed based on four factors that affect the yield of polysaccharides including the extracting time and temperature, extracting times and the solid to solution ratio. The optimized condition to extract polysaccharides was established as extracted two times with 40 times volume of boiling water, two hours for each extraction. The active component analysis showed that the production rate of polysaccharides was up to 15.25% in Medium 4, which was the most advantageous for the accumulation of polysaccharides in the fruiting body of Cordyceps militaris. The production rate of mannite was up to 7.00% in Medium 3, which was the best medium for accumulation of mannite in the fruiting body. Medium 1 was the most advantageous for accumulation of antioxidant substances in the fruiting body, the inhibitate rate of Pyrogallol auto-xidant of the liquid extracts from fruiting body was 62.12%.Combine the above four analyses, the Medium 10 is the best medium to improve the total quality of Cordyceps militaris.更多还原