The Comparison of Typical Organic Solvents and Ionic Liquid for More Environmentally and User-Friendly Pyocyanin Extraction

Pyocyanin is a pigment that recently gained importance as a valuable chemical. Most often, the method for extraction is based on the use of chloroform. Therefore, an efficient and more environmentally friendly method is vital for further use. We compared organic solvents and ionic liquids as pyocyanin extractants. We assessed the extraction efficiency using a pyocyanin standard and pyocyanin extracted directly from the bacterial culture. The results showed that only chloroform, dichloromethane, and ethyl acetate were useful for pyocyanin extraction among the tested organic solvents. Extraction with chloroform was the most efficient method. Notably, the ionic liquid could also be favorable for the extraction process, exhibiting antibacterial properties and being separated from the pigment by adsorbing pyocyanin on clays and desorbing it with ethanol. The extraction of pyocyanin can be led by using alternative extractants, i.e., dichloromethane or ionic liquid, and therefore, it can be less hazardous for the environment and the user.