长期储藏干燥发菜超微结构和生理特性分析

Analysis on Ultrastructures and Physiological Characteristics of Dry Nostoc flagelliforme in Long-term Storage

发菜是一种生长在干旱―半干旱荒漠地带的陆生固氮蓝藻,具有很强的旱生生态适应性。对野生干燥发菜与储藏10年的干燥发菜进行超微结构和生理特性比较分析。结果表明:与野生干燥发菜相比,长期储藏的发菜胶质鞘较为紧密,结构颗粒数目没有明显变化,无净光合速率,暗呼吸速率、叶绿素a、藻蓝素、别藻蓝素和藻红素含量较低,而脯氨酸、可溶性蛋白、可溶性糖、类胡萝卜素、丙二醛、过氧化氢和超氧阴离子自由基的含量及SOD、CAT活性和Vc含量较高。研究结果为深入探讨发菜长期储藏后仍能恢复生命活力的机理奠定了基础。

Nostoc flagelliforme is a terrestrial nitrogen-fixing cyanobacterium and generally grows in arid and semi-arid desert. It has evolved a unique capability to tolerate desiccation and can survive for several decades under extremely dry conditions, and rapidly recover physiological metabolic activity after reab- sorbing water. The differences about the uhrastructural and physiological characteristics of dry N. flagelli- forme between wild state and ten years storage were studied. The results showed that, under the condi- tions of ten years storage, the colonies sheath was shrunk, the amount of structural granules were not changed significantly, net photosynthetic rate and dark respiration rate were relatively weak, the content of Chlorophyll a, phycocyanin, allophycocyanin and phycoerythrin decreased, while carotenoid content increased. Morever, proline, soluble protein, soluble sugar, MDA, H202, 02 and Vc contents and the activities of SOD and CAT were higher than that of in wild state. The results provide a basis for the stud- ies on the adaptation mechanism for long term storage of N. flagelliforme.