Abstract: Objective: To investigate the effect of high altitude environment condition on the antioxidation of water extracts fromCelosia cristata L.Methods: The seeds of C. cristata L. cv. Spicata Tuansuihuang were carried by a high-altitude balloon (CHAB)for space mutation, flying to an altitude of 40.112 km from sea level for about 4 hours. After returning to the ground, the treatedseeds were cultivated on the ground and the inflorescences and leaves of SP1 generation were collected. Adding 4 kinds of thewater extracts of the inflorescences and leaves of CHAB groups and the control groups respectively to the hydroxyl radical(•OH) and superoxide radical (O2-•) generating and detecting systems for the observation on their competitive abilities to activeoxygen reactions teste by colorimetric method. The contents of VC, flavonols and activity of SOD of all samples were alsoanalyzed and determined respectively. Then, the relationship between the antioxidation activity of samples and the contentsand activity of free radical scavengers in samples was investigated for the effect of high altitude environment. Result: The waterextracts of all samples could reduce •OH initiated oxidation of reductive Cyt•c(Ⅱ) and inhibit O2-•initiated oxidation ofhydroxylamine. But, the copabilities of scavenging active oxygen of 2 kinds of water extracts from CHAB groups weresignificantly higher than those of the control. The obvious positive correlationship existed between the above results and alsobetween the increase of the contents and the activity of free radical scavengers in the samples of CHAB. Conclusion: Theevident effects of high space environment condition mutation on the synthesis of the antioxidation active substances and theincrease of antioxidation capability in C. cristata L. were observed.

Key words: Celosia cristata L., high altitude environment, active oxygen, scavenging effect, mutation effect