Characterization of Biological Activity and Evaluation of Exogenous Metabolites of Cyanobacteria ‘Anabaena’ sp. IPPAS B-2020

The culture of a cyanobacterium ‘Anabaena’ sp. was isolated from alluvial meadow soils in the south of Russia and deposited in the IPPAS collection of cultures of microalgae and cyanobacteria, Timiryazev Institute of Plant Physiology, Russian Academy of Sciences, under the number IPPAS B-2020. Phylogenetic analysis showed that the studied strain belongs to a clade comprising the genera Sphaerospermopsis, Amphiheterocytum, Raphidiopsis, Wollea, and Neowollea, but cannot currently be assigned to any of them. The phytotoxicity and fungicidal and antioxidant activities of the strain were studied. The culture turned out to be non-toxic. Water–alcohol extract and biomass of ‘Anabaena’ sp. IPPAS B-2020 completely suppressed the micromycetes Fusarium culmorum, F. graminearum, and F. sporotrichioides with the maximum diameter of growth inhibition zone of 2.5 cm. The water extract of cyanobacteria ‘Anabaena’ sp. IPPAS B-2020 had a pronounced antioxidant activity (39.3%). Among the metabolites of ‘Anabaena’ sp. IPPAS B-2020, there were organic acids (citric, lactic, acetic), terpenes, alkanes, alcohols, and other low molecular weight organic compounds. The ‘Anabaena’ sp. IPPAS B-2020 culture is of interest for biotechnology as a producer of such important biologically active compounds as tributyl phosphate, D-limonene, squalene, and α-pinene.