Praveena, B, Murthy, S.D.S
Depletion in the ozone layer leads to the entry of ultraviolet-B (UV) rays on to the earth surface which causes the damage to the cyanobacterial systems. The aim of the present study is to observe the characterisation of possible enzymatic and non-enzymatic antioxidant adaptations against UV-B radiation in the cyanobacterium Spirulina platensis. The enzymatic antioxidants like superoxide dismutase (SOD) and catalase (CAT) were measured in control and treated results in increase in the concentration of the enzymatic antioxidants results in the protection. Preliminary phytochemical screening of the enzymatic antioxidants like carotenoids, phenols, flavonoids and anthocyanins are measured which results in increase in the concentrations upon treatment with UV-B radiation. Methanolic extracts of the Spirulina platensis were screened for the presence of mycosporine like aminoacids (MAAs). Increase in the concentration of MAAs results in the protection of the cyanobacterium against UV-B. Keywords: Anthocyanins, Catalase, Carotenoids, Flavonoids, MAAs, Phenols.