Evaluating the photoprotective potential of Leptolyngbya sp.

Cyanobacteria, can be found in many different terrestrial or aquatic habitats that are sometimes unbearable for many other organisms. Biosynthesis of mycosporine-like amino acids (MAAs) enables growth in such environments due to their UV screening and antioxidant activity. MAAs are water-soluble bioactive molecules with vast biotechnological potentials due to their UV screening properties and antioxidant activities. In the present study, the occurrence of MAAs in the cyanobacterium Leptolyngbya sp. (Gomont) Anagnostidis and Komárek was assessed by HPLC–PDA ESI–MS analysis. The combination of UV and MS data values revealed the occurrence of nine different MAAs, including; palythine (1), palythenic acid (2), euhalothece-362 (3), palythene (4), usujirene (5), palythine serine (6), asterina-330 (7), palythinol (8), and palythine-threonine (9). As well, some different in vitro antioxidant assays such as ABTS, FRAP, and RP were applied to evaluate the antioxidant properties of the MAA-enriched extract. The results indicate a significant and dose-dependent antioxidant activity of the MAA-enriched extract (54% ABTS scavenging activity at the dose of 2 mg mL⁻¹ extract) in this cyanobacterium which was comparable with those of ascorbic acid (81% antioxidation rate at 2 mg mL⁻¹ of ascorbic acid). All these observations suggest that Leptolyngbya sp. may act as a new, promising source of MAA compounds. [ABSTRACT FROM AUTHOR]