Transit to Mars: low-dose γ-irradiation (Co60) induces small hormesis effect on Limnospira indica, a component of the MELiSSA life support system for space exploration

ABSTRACT: In this study, two experiments using low-dose gamma irradiation (Co60, 70.4 µGy h-1 and 52.5 µGy h-1) to mimic the impact of 8-weeks of Mars transit flight of semi-continuous cultures of L. indica were performed. In the first experiment, the consecutive batches were 2 weeks long. After 2 weeks, 5% of the culture was transferred to a new flask and new medium was added. In the second experiment, the batches lasted 1 week. 25% of culture was transferred to the next run. In both approaches, the cultures were continuously illuminated (full PAR, 45 µmol photons m-2 s-1, LEDs) and shaken (120 rpm). A transient hormesis effect has been observed in the first 4 weeks of experiment 1, meaning that several growth and health parameters of the irradiated cultures increased compared to the controls in this time period. Two parameters could cause the pronounced effect of irradiation in exp. 1. Firstly, the higher variation in light and irradiation per cell ratio, caused by the different dilution schemes. Secondly, the higher irradiation dose due to the decay of the source between experiment 1 and 2.

INSTRUMENT(S): autoflex

ORGANISM(S): Limnospira Indica Pcc 8005

SUBMITTER: Felice Mastroleo  

LAB HEAD: Natalie Leys

PROVIDER: PXD051709 | Pride | 2025-05-06

REPOSITORIES: Pride