Effects of salidroside on functional and structural changes in highland barley proteins

This study investigates the functional and conformational changes in highland barley proteins (HBPs)-salidroside complexes formed by non-covalent bond interactions. The free sulfhydryl contents of HBPs are decreased from 37.65 +/- 1.90 mu mol/g protein to 18.86 +/- 0.14 mu mol/g protein after binding with salidroside. The fluorescence spectroscopy show that two fluorescence peaks are observed and salidroside enhance the fluorescence intensity of HBPs at the high addition level of salidroside (0.5-1 mmol/g protein). Secondary structure, surface hydrophobicity, and Zeta potential of HBPs are also changed by salidroside with different addition level (0-1 mmol/g protein). HBPs-salidroside complexes exhibit better functional properties (emulsifying and foaming properties) than HBPs, which is probably due to conformational changes in the HBPs. The combination of HBPs and salidroside increase the antioxidant ability of HBPs. Overall, salidroside has the potential to improve the structural characteristics and functional properties of HBPs, especially their antioxidant ability.