New strains of green microalgae from extreme environments in Crimea: identification using an integrative taxonomic approach

Abstract

This study was conducted as part of a project to establish a bioresource collection of carotenogenic microalgae from the Crimean region with the aim of identifying promising strains adapted to the climatic conditions of southern Russia. A large-scale sampling campaign was carried out in extreme habitats of the western and south-eastern parts of the peninsula, resulting in the isolation and characterization of five novel strains of green algae. Taxonomic identification was performed using an integrative approach that combined analysis of life cycle traits, morphological characterization by light and scanning electron microscopy, and phylogenetic analysis of the nuclear ribosomal DNA region (ITS1–5.8S–ITS2). The strains were assigned to four genera within the classes Chlorophyceae (Coelastrella thermophila IBSS-98, Tetradesmus obliquus IBSS-164, Desmodesmus multivariabilis IBSS-167 and IBSS-171) and Trebouxiophyceae (Dictyosphaerium ehrenbergianum IBSS-163). All strains represent species new to the IBSS collection and were obtained in pure culture from the Crimean algal flora for the first time. The broad range of biotechnological applications for these strains – from environmental remediation to production of high-value compounds for the pharmaceutical, cosmetic, and food industries, as well as biofuels – highlights the importance of further research and supports the potential for regional economic development.