简介：Topreparecalcium-bindingpeptides,thefleshresidueofMactraVeneriformiswassubjectedtoenzymatichydrolysis.Bycomparingthecapabilityofcombiningcalciumofthehydrolyzates,pepsinwasconfirmedtobethemostsuitableenzymeforhydrolyzingthefleshresiduetoreleasecalcium-bindingpeptidesamongtheseventestedproteases.Thepepsinhydrolyzate(PHM)wasdividedintothreefractionsaccordingtothemoleculeweightofitscomposition,whichrangedfrom0.5to15kDa.Thelow-molecule-weightfractionnamedPHM-3hadthehighestcapabilityincombiningcalcium.ThepeptidesexistinginthePHM-3fractionconsistedofhighercontentsofGlu,AlaandLeu,andcouldproduceonetypeofcalcium-peptidecomplexbypowerfullychelatingcalciumions.PHM-3productscouldeffectivelyincreasecalciumabsorptionandretentionwhiletheydecreasedthecalciumexcretioninanimaltests.Additionally,symptomscausedbylowcalciumbioavailabilityinovariectomizedrats,suchasbonemineraldensityreductionandmechanicalstrengthlosscouldbesignificantlyamelioratedbythehydrolyticproductsadditionindiet.