Algae cultivation in Ultra-high concentration Amino acid based ionic liquids

Abstract

Liquid water is an important solvent for carbon-based life, due to its special structure and hydrogen bond engaging the biochemical reactions and energy transformations in the cell. However, the liquid window of water is narrow, within 0–100 °C at 1 atm. When water is partly replaced using ionic liquids (ILs) to transfer energy and nutrition, life activities may happen at a wide temperature range and a wide pressure range on earth, in the solar system and the universe. Aqueous Gly-based ILs were employed as a culture medium for the cultivation of algae. Four different kinds of Gly-based ILs were first synthesized by neutral reaction. Structure of synthesized ILs was confirmed by FT-IR and NMR. Furthermore, effect of Gly-based ILs concentration on algae growth was investigated. Growth rate of algae was tested by microscope and UV–vis according to the absorption of chlorophyll. The Gly-based IL presented higher biological compatibility of algae than previous work. The highest concentration of glycine phosphate suit for algae cultivation is 15 % and the algae could reproduce for 30 days without obvious inhibition. This research is promising work in the context of the cultivation of algae in amino acid IL based culture medium and exploring the life activity restricted zone on earth.