荷叶离褶伞胞外酶活性变化规律与其生长发育相关性研究

Lyophyllum decastes, is a precious culinary mushroom, and is rich in protein(21.4%), essential amino acids (about 40.19% of total amino acids), linoleic acid and vitamin in the fruit bodies. It has a high utilization value due to abundant nutrition. The present studies have mainly focused on biological characteristics.Few publications on basic physiological, such as activity of extracellular enzymes and their relation with growth and development are available, the problems of grow slowly and low production are unresolved. The project was to study extracellular enzymes and the change rule of them activity, the capacity of extracellular enzymes degrade culture material, the factors that affect the activity ofextracellular enzymes, the relationship between growth and development and extracellular enzymes and the mechanism of them influence each other and the method regulates growth and development processes. Such a research allows us to further understand the basic physiology and extracellular enzymes (including sorts, the change rule of them activity, the factors that influence their activity, the law of them degrade culture material and the mechanism of them influence each other with growth and development). The study will provide theoretical direction for the strategy which regulates the processes of growth and development through control the activity of extracellular enzymes.

荷叶离褶伞 Lyophyllum decastes（Fr.:Fr.）Sing.是珍稀食用菌，子实体中蛋白质含量达21.4%，必需氨基酸占氨基酸总量40.19%，亚油酸、维生素等含量丰富，其营养价值高，利用价值大。目前，国内外学者对其生物学特性等方面进行了研究，但对其胞外酶活性变化规律、生长发育与胞外酶活性变化规律相关性等生理基础问题缺乏研究；生产周期长，产量低等生产问题也未解决。本项目计划通过研究荷叶离褶伞胞外酶及其活性变化规律、胞外酶对木质纤维素等培养料之降解能力、胞外酶活性影响因子、生长发育与胞外酶的关系及其相互影响机制、调控生长发育进程方法。掌握荷叶离褶伞胞外酶种类、活性变化规律；深化对荷叶离褶伞生理基础的认识；明确影响荷叶离褶伞胞外酶活性的因素；了解胞外酶对培养料的降解规律；阐释生长发育与胞外酶之关系及其相互影响机制；为探索通过调控胞外酶活性进而调控生长发育的关键技术提供理论。

荷叶离褶伞胞外酶参与调控其生长发育进程。本课题通过对荷叶离褶伞不同生长发育时期胞外酶活性变化规律、胞外酶对木质纤维素等培养料降解能力、荷叶离褶伞生长发育与胞外酶的关系以及胞外酶活性影响因子等进行研究。结果表明：荷叶离褶伞胞外酶含漆酶、锰过氧化物酶、木质素过氧化物酶、半纤维素酶、纤维素酶、滤纸酶、淀粉酶、酸性蛋白酶、中性蛋白酶、焦磷酸化酶及糖原磷酸化酶等11种酶；对荷叶离褶伞胞外酶活性影响因子进行研究表明，主料为木屑培养料、辅料为麸皮培养料、C/N在50-65、大量元素KH2PO4、温度（25.0±0.5）℃、pH4-7、微量元素ZnSO4及维生素VC和VPP均可显著促进荷叶离褶伞胞外酶活性；对荷叶离褶伞整个生长发育时期胞外酶活力研究表明，木质素酶系（漆酶、锰过氧化物酶、木质素过氧化物酶）、羧甲基纤维素酶、半纤维素酶、滤纸酶六种胞外酶活性变化具有明显的阶段性，木质素酶系在菌丝生长阶段酶活性较子实体生长阶段高，羧甲基纤维素酶、半纤维素酶、滤纸酶在菌丝生长阶段较子实体生长阶段低，淀粉酶在荷叶离褶伞生长发育的不同时期酶活性较低；对胞外酶降解培养料规律研究表明，半纤维素、纤维素、木质素的降解量在不同生长期总体呈上升趋势，木质素降解量在菌丝生长阶段较半纤维素、纤维素高，说明荷叶离褶伞生长过程中优先利用木质素；营养生长期木质素降解量与漆酶活力正相关，纤维素降解量与滤纸酶活力正相关，半纤维素降解量与半纤维素酶活力正相关；荷叶离褶伞生长发育与胞外酶相关性研究表明，菌丝营养生长与锰过氧化物酶、漆酶、木质素过氧化物酶及半纤维素酶活性呈正相关；调控锰过氧化物酶、漆酶、木质素过氧化物酶及半纤维素酶活性，进而调控荷叶离褶伞生长发育进程的工作正在进行。综合上述结果，本研究为探讨荷叶离褶伞胞外酶活性种类及其变化规律奠定了坚实的工作基础，同时为揭示荷叶离褶伞生长发育进程与胞外酶活性之间的关系提供了重要线索。