Study On The Physicochemical, Functional Properties And Structure-activity Relationship Of Silver Carp Myofibrillar Protein Glycosylation Modified Complex

Myofibrillar protein?Mf?from silver carp was incubated with KOG?maltodextrin and glucose for 0-96 h at 50oC and 75%relative humidity to obtain glycoconjugates in different periods of Maillard reaction.Physicochemical properties and functional properties were determined,and structure-functional models were established.The main contents and results are as follows:?1?With the process of glycation reaction,the electrophoretic mobility of myosin heavy chain and actin decreased slightly.Meanwhile,the amount of saccharides bound to Mf increased simultaneously.The binding KOG,maltodextrin and glucose increased to110?g/mg,105?g/mg and 22?g/mg after 96 h.And the avaliable amino acid groups decreased to 52%,49%and 40%of the initial value,respectively.These results indicated that glycation occurred successfully,and the reaction of glucose and Mf was faster than polysaccharide.In addition,the Vicosity of MRPs was improved and the measured pH decreased through glycation.These results indicated that glycation changed the surface properties and conformation of Mf.?2?With the process of glycation reaction,the activity of Ca²⁺-ATP and SH of Mf decreased due to the degeneration of Mf.While polysaccharides had protective effect on Mf during reaction.The activity of Ca²⁺-ATP and SH of Mf-KOG and Mf-mal were higher than Mf-glu.?3?With the process of glycation reaction,the peak tempetature of Mf-KOG,Mf-mal and Mf-glu were improved from 64oC to 86oC,from 62oC to 85oC,from 60oC to 78oC,respectively.The surface hydrophobicity of Mf-KOG,Mf-mal and Mf-glu were decreased from 40?g to 18?g,from 42?g to 32?g,from 43?g to 30?g,respectively.?4?In low ionic strength medium,total solubility of MRPs increased with glycation.Meanwhile,the enhancement of the solubility of Mf-mal was weaker than Mf-KOG and Mf-glu.In high ionic strength medium,the solubility had a decrease from 25%.The heat stability of MRPs dropped at 2-5 h,and then rose significantly even to 80-90%.Moreover,the emulsifying properties and foaming properties improved through glycation at 8-12 h,and then decreased.The emulsifying properties and foaming properties of Mf-KOG and Mf-mal were better than Mf-glu.These results indicated that,the regulation of the glycation in the early stage is important for the improvement of functional properties.In addition,polysaccharide is more available to improve the heat stability,emulsifying properties and foaming properties of Mf through glycation,while monosaccharide is superior in enhancing the solubility.?5?In the process of vitro digestion,the band of 116 kDa and 36-45 kDa degraded gradually,and the band of 6.5-20 kDa generated.The results showed that,the vitro digestion of Mf accelerated through glycation.In addition,Mf-KOG products was resistant to digestion obviously,showed that polysaccharide had the effect of resistance to digestion.?6?According to the model of structure-function of MRPs,this task discussed the effect of physicochemical properties on functional properties.In Mf-KOG products,the most significant impact on solubility,emulsifying activity,emulsion and foaming stability were Cp,Vi,Cp and Cp with Sh,respectively.In Mf-mal products,the most significant impact on solubility,emulsifying activity,emulsion and foaming stability were mpH,mpH,mpH with Vi and mpH with Vi,respectively.In Mf-glu products,the most significant impact on solubility,emulsifying activity,emulsion and foaming stability were Sh,mpH with Sh,Cp and mpH with Vi,respectively.This study showed that glycation could significantly improve the functional properties of Mf,and supply the the theoretical basis of glycosylation reaction.The results of this study will provide the scientific basis for the application of protein in food industries.