Effect Of Adverse Stress On Physiological And Biochemical Of Nostoc Flagelliforme Cell

Nostoc flagelliforme is a kind of terrestrial cyanobacteria, it has high medicinaland economic value, and plays an important role in prevention of desertification.Atpresent, with the deterioration of the ecological environment, the stress resistanceattracts more and more attention.The method of antibiotics and axenic culture was adopted to purificate the liquidsuspension culture Nostoc flagelliforme. The electrolyte leakage, MDA content, SODactivity, proline, total soluble protein and trehalose contents of Nostoc flagelliformeunder stresses were determinated.The main results obtained were as follows:1. Under different high temperature stress, the electrolyte leakage and MDAcontent increased, the SOD activity increased first and then decreased with hightemperature stress heavier, the content of Pro, soluble protein and trehalose increased.2. The electrolyte leakage and MDA content of the Nostoc flagelliformeincreased with the saline alkali stress aggravater, the SOD activity and Pro contentadded first and then reduced, the content of soluble protein decreased, but the trehaloseincreased under the whole stress.3. Under the Cu²⁺、Cr²⁺and Pb²⁺stress, the electrolyte leakage and MDAcontent increased.The SOD activity increased at the concentration under10mg/L, andthen decreased with the stress heavier, the content of Pro, soluble protein and trehaloseadded first and then decreased at the contentration above10mg/L as the same as theSOD activity.4. Study on the heavy metals ion intercross stress, the result showed that thedifferences among the contentrations were significant（p＜0.01）, but the interclassdifference patency was not significant.5. Under the high temperature and saline alkali intercross stress, the electrolyteleakage increased nearly200%, the content of MDA, Pro and SOD activity increased first and then decreased, the content of soluble protein and trehalose added the wholestress course.The stress experiments indicate that the Nostoc flagelliforme has stronger self-protection system, and it can resist the minor damage of bad surroundings and have acertain resistance ability under the adverse circumstances.