Ionic liquid-based microwave-assisted extraction of protein from Nannochloropsis sp. biomass

Considerable evidence supports the enhanced utilization of high-quality protein to obtain optimal health subsequences. Microalgae are a valorous source of proteins that can be employed as functional, nutritional, and remedial supplies. An effective microwave-assisted extraction method based on ionic liquids has been utilized in this study to extract proteins from microalgae Nannochloropsis oceanica biomass. The study of microwave-assisted extraction was carried out under varying conditions of temperature (30–80 °C), extraction time (5–35 min), and IL concentration (0–4.67% w/v). Among the six types of examined IL, choline acetate was an effective one for extracting total protein from microalgae biomass. The highest protein yield was obtained at 0.5 g microalgae, 2% w/v [Ch][Ac], and 40 °C for 30 min, representing 26.35% of protein yield and 65.06% of total protein extracted from the Nannochloropsis oceanica biomass. Meanwhile, conventional method of Soxhlet resulted in the protein yield of 0.63%. Only 1.56% of total Nannochloropsis oceanica protein was extracted by extraction method of Soxhlet which uses the hazardous solvent. The outcomes illustrated the superiority of [Ch][Ac]-based microwave-assisted extraction to conventional methods. This innovative procedure is recommended to have significant usage for the separation of proteins. The outcomes from this study would be beneficial in recognizing and harnessing significant microalgae biochemical from IL-based microwave-assisted extraction process to develop new and improved bioproduct technologies.