灰树花液体培养过程中底物利用与菌丝超微结构的变化

Alternative Substrate Utilization and Ultramicrostructure of Hyphae in the Submerged Cultivation of Grifola frondosa

研究了灰树花深层发酵过程中底物利用与菌丝超微结构的关系。发酵的不同时期菌丝利用的底物不同,菌丝的超微结构也呈现出相应的变化。发酵早期的菌丝主要利用碳水化合物,结构上表现为线粒体丰富,液泡化程度低。发酵中期,菌丝开始分化,液泡增多增大,并通过内吞作用积累了一些脂质物质。这一时期超微结构上最大的特征是菌丝分化出顶囊以及膜边体,细胞内的膜系统分化出圆球体、初级溶酶体、次级溶酶体等结构,其中溶酶体内的各种水解酶负责水解蛋白质、脂肪等大分子;发酵后期菌丝高度液泡化,积累并利用脂质体,主要通过脂类分解代谢维持生命活动。

Alternative substrate utilization and ultramicrostructure of hyphae in the submerged cultivation of Grifola frondosa was studied in this paper. Appropriate substrate was utilized at different stage of submerged cultivation, and corresponding ultramicrostructure of hyphae was observed. Carbohydrates were taken as the main substrate and the hyphae were rich in mitochondria while the degree of vacuolization was low at the early stage. Lipoid was accumulated while the vacuole was increasing in both quantity and size in the hyphae as a sign of differentiation at the middle stage. The ultramicrostructure of hyphae was specialized in tip-vosicles and lomasome. The membrane system inside the hyphae was differentiated as spherosome, primary lysosome and secondary lysosome when lysis proteins and lipoids into smaller moleculars. The degree of vacuolization was much higher while the accumulated lipoid was taken as alternative substrate to maintain the life of the hyphae at the later state.