Phylogeny and Fatty Acid Profiles of New <i>Pinnularia</i> (Bacillariophyta) Species from Soils of Vietnam

• Published in: Cells
• Main Authors: Elena Kezlya, Yevhen Maltsev, Sergei Genkal, Zinaida Krivova, Maxim Kulikovskiy
• Format: Article
• Language: English
• Published: MDPI AG 2022-08-01
• Subjects: 18S rDNA; biotechnology; diatoms; morphology; <i>rbc</i>L; taxonomy
• Online Access: https://www.mdpi.com/2073-4409/11/15/2446

We studied the morphology, ultrastructure, and phylogeny of eight soil diatom strains assigned to the <i>Pinnularia</i> genus. Six of these strains, identified by us as new species, are described for the first time. We provide a comprehensive comparison with related species and include ecological data. Molecular phylogeny reconstruction using 18S rDNA and <i>rbc</i>L affiliates the new strains with different subclades within <i>Pinnularia</i>, including ‘borealis’, ‘grunowii’ and ‘stomatophora’. We also studied the fatty acid profiles in connection with the emerging biotechnological value of diatoms as a source of lipids. Stearic (36.0–64.4%), palmitic (20.1–30.4%), and palmitoleic (up to 20.8%) acids were the dominant fatty acids in the algae cultured on Waris-H + Si medium. High yields of saturated and monounsaturated fatty acids position the novel <i>Pinnularia</i> strains as a promising feedstock for biofuel production.