Biochemical composition and antioxidant activities of Arthrospira (Spirulina) platensis in response to gamma irradiation

Arthrospira (Spirulina) platensis is a blue-green alga, rich with bioactive components and nutrients. To evaluate effect of gamma irradiation, A. platensis was exposed to different doses of 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 kGy. The data showed that the phenolic and proline contents significantly increased with the increase of gamma irradiation doses up to 2.0 kGy, above which a reduction was observed. The soluble proteins and malondialdehyde (MDA) contents were stimulated by all tested irradiation doses. Furthermore, the vitamins (A, K and B group) and mineral contents (N, P, Na, K, Ca, Mg and Fe) were stimulated by the irradiation doses compared with the control. The activities of some N-assimilating and antioxidant enzymes were significantly increased with the irradiation doses up to 2.0 kGy. This study suggests the possible use of gamma irradiation as a stimulatory agent to raise the nutritive value and antioxidant activity of A. platensis.