Effect of different extraction methods on physicochemical, functional and antioxidant properties of bamboo shoot protein

This study aims to evaluate the physicochemical, functional, and antioxidant properties of bamboo shoot protein (BSP) produced by alkali isoelectric precipitation and ultrasound- and enzyme-assisted alkali extraction methods. The extraction method significantly affected the properties of BSP. Both ultrasound- and enzyme-assisted extractions resulted in higher protein recovery yield and purity compared to alkali isoelectric precipitation. SDS-PAGE results indicated that BSP exhibited low molecular weight (12–65 kDa). However, ultrasonication and enzymatic digestion disrupted the secondary and tertiary structures of proteins, leading to smaller particle sizes and higher levels of β-turn and random coil content. In this study, BSP isolated using enzymatic-assisted alkali extraction (E-BSP) showed the highest solubility, foaming stability, emulsion activity index, water-holding capacity, and fat absorption capacity. Moreover, E-BSP exhibited the lowest IC 50 values for scavenging hydroxyl radicals (2.90 mg/mL) and ABTS + radicals (0.39 mg/mL). These findings provide a basis for the high-value utilization of bamboo shoots in the food industry.