Functional characterization of a novel lipoxygenase from Aliikangiella coralliicola for natural modification on gelation of soy protein isolate

Lipoxygenase (LOX) can catalyze the production of hydroperoxides from polyunsaturated fatty acids, offering promising applications in the food industries with especial contribution of naturally modified function for food gelation. To date, commercially available LOXs primarily sourced from soybean meal, facing challenges such as containing isoenzymes and exhibiting low catalytic activity for broad utilization restrictions. Herein, a LOX was first derived from the marine microorganism Aliikangiella coralliicola (AcLOX) with a molecular weight of 80 kDa expressed in Escherichia coli . AcLOX exhibited good stability over a wide pH range of 4.0–9.0. Additionally, AcLOX displayed specific activity against α-Linolenic acid (ALA) of 6.67 × 10 4 U/mg, and kinetic parameters values for K m , k cat , and k cat / K m of 0.58 μM, 1.40 s −1 , and 2.42 μM −1  s −1 , respectively. Moreover, Ca 2+ and dimethyl sulfoxide (DMSO) activated the activity of AcLOX. To explore its gelation modification ability, AcLOX was applied to induce the cross-linking of soy protein isolate (SPI) subunits with increased particle size, potential, surface hydrophobicity (S o ), and as well as gel hardness at appropriate concentrations. This is the inaugural study to unveil the gelation modification ability of LOX from Aliikangiella coralliicola . These findings provide superior enzymatic performance and cross-linking potential of AcLOX for industrial applications.