Analysis of Anabaena vaginicola and Nostoc calcicola from Northern Iran, as rich sources of major carotenoids

► Four major carotenoids were determined in three Iranian cyanobacterial isolates. ► High contents of lycopene and β-carotene were observed in these isolates. ► The isolates also contain cis isomers which lead to more bioavailability. ► These isolates are introduced as promising natural sources of lycopene and β-carotene.