The heat-induced formation of molecular polymers betweenβ-lactoglobulin(β-LG)and the milk fat globule membrane(MFGM)has been widely recognized;nevertheless,the molecular mechanisms underlying this formation remain u...The heat-induced formation of molecular polymers betweenβ-lactoglobulin(β-LG)and the milk fat globule membrane(MFGM)has been widely recognized;nevertheless,the molecular mechanisms underlying this formation remain unclear.This study aimed to investigate the binding mechanisms and physicochemical properties of complexes formed betweenβ-LG and MFGM under two distinct heat treatment conditions:63℃for 30 min and 90℃for 15 min.Differential scanning calorimetry analysis indicated that heating the complexes at 90℃for 15 min enhanced their thermal stability.Following this treatment,MFGM-protein complexes exhibited decreased intrinsic fluorescence intensity and a blue shift in the maximum emission wavelength.To elucidate the molecular mechanisms underlying complex formation,blocking agents including dithiobis-nitrobenzoic acid,N-ethylmaleimide,and dithioerythritol were applied at both 63℃/30 min and 90℃/15 min,followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.The results demonstrate thatβ-LG-MFGM complex formation involves disulfide bonds(notably Cys~(121)),hydrogen bonding,hydrophobic interactions,and electrostatic interactions,in addition to general intermolecular forces.Heat treatment was found to promote both the formation and thermal stability of these complexes.These findings provide a mechanistic basis for further investigation of how heat processing influences the digestive behavior and functional properties ofβ-LG-MFGM complexes.展开更多
基金supported by the National Key Research and Development Program of China(No.2022YFD1301000)the National Center of Technology Innovation for Dairy(No.2024-FWPT-001)+1 种基金the Qingdao Agricultural University Haidu College Research Project Fund(No.KY202305)the Qingdao Science and Technology Benefiting the People Demonstration Project(No.25-1-5-xdny-32-nsh),China。
文摘The heat-induced formation of molecular polymers betweenβ-lactoglobulin(β-LG)and the milk fat globule membrane(MFGM)has been widely recognized;nevertheless,the molecular mechanisms underlying this formation remain unclear.This study aimed to investigate the binding mechanisms and physicochemical properties of complexes formed betweenβ-LG and MFGM under two distinct heat treatment conditions:63℃for 30 min and 90℃for 15 min.Differential scanning calorimetry analysis indicated that heating the complexes at 90℃for 15 min enhanced their thermal stability.Following this treatment,MFGM-protein complexes exhibited decreased intrinsic fluorescence intensity and a blue shift in the maximum emission wavelength.To elucidate the molecular mechanisms underlying complex formation,blocking agents including dithiobis-nitrobenzoic acid,N-ethylmaleimide,and dithioerythritol were applied at both 63℃/30 min and 90℃/15 min,followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.The results demonstrate thatβ-LG-MFGM complex formation involves disulfide bonds(notably Cys~(121)),hydrogen bonding,hydrophobic interactions,and electrostatic interactions,in addition to general intermolecular forces.Heat treatment was found to promote both the formation and thermal stability of these complexes.These findings provide a mechanistic basis for further investigation of how heat processing influences the digestive behavior and functional properties ofβ-LG-MFGM complexes.
