This study reports a comprehensive set of experimentally measured surface properties of six oleaginous green microalgae. The results showed that the hydrophobic character of the six microalgae, determined by the contact angle method, was more accurate than by using the microbial adhesion to solvents (MATS) method. However, they both indicated that all studied microalgae presented an electron donor parameter. Due to the abundant surface carboxyl, phosphoryl, and hydroxyl groups, all microalgae presented a negatively charged surface. Monoraphidium dybowoskii XJ-377 was the most hydrophobic strain with a negative ΔG coh and the lowest surface free energy. Kirchneriella dianae XJ-93 had the lowest total surface functional group concentration and the lowest surface area, which can lower the harvesting cost. Overall, cellular surface properties should be evaluated and considered in oleaginous microalgal screening and identification in addition to the biomass and oil production normally considered.
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