Physicochemical characteristics and anti-inflammatory properties of Zophobas morio (super mealworm) protein extracted by different methods

In this study, Zophobas morio protein (ZMP) was extracted via combining alkaline extraction with ultrasound-assisted (AE-UAE) or microwave-assisted (AE-MAE) extraction in comparison with their respective single extraction methods and conventional method. AE-UAE and AE-MAE exhibited a higher extraction yield (40.68 % and 36.80 %, respectively) than single methods and conventional method (29.19 %–35.89 %). SDS-PAGE showed AE-UAE and AE-MAE induced new formation of smaller molecular weight proteins. Moreover, the hybrid methods decreased α-helix content, whereas increased β-sheet by unfolding the structure of ZMPs. ZMPs demonstrated significant anti-inflammatory properties by ameliorating LPS-induced macrophage activation and subsequent excessive expression of immune modulators in RAW264.7 cells. Notably, at 200 μg/mL, AE-UAE protein reduced approximately 65 % of nitric oxide and 85 % of iNOS expression, decreased TNF-α secretion by 35 % and IL-6 secretion by 68 %, and decreased CD80 expression by 50 %. In conclusion, the proposed hybrid methods are applicable for efficient extraction of ZMP with improved biological activities.