Construction And Performance Study Of Enzymatic Hydrolyzed Sodium Caseinate Loaded Tanshinone Iia Nanoformulations

In recent years,plant-derived bioactive compounds have received much attention for their excellent antioxidant,anti-inflammatory,anti-cancer and immunomodulatory activities.Among these bioactive compounds,Tanshinone IIA(TA)has become a very valuable active ingredient for research due to its excellent anti-inflammatory,bactericidal,anti-tumor,antioxidant,anti-cardiovascular disease and anti-osteoporosis activities.At present,the clinical application of TA is severely limited by its physicochemical properties.The solubility of TA in water is almost negligible,resulting in its extremely poor oral bioavailability and absolute bioavailability(< 3.5%);it quickly loses its activity under harsh external conditions(such as light,high temperature and acid-base,etc.).In addition,TA is difficult to act on the target at micron size in aqueous solution,thus making it difficult to be effective.This project focuses on sodium caseinate(NaCas)and its enzymatic hydrolysis products as nanoprotein carriers for enhancing the physicochemical properties and biological activity of hydrophobic active substances and making up for the deficiencies of TA in clinical applications.By studying the preparation of nanoparticles,we hope to make some contribution to the innovation of protein drug carriers.The work included is as follows.1.The target enzyme was selected for the enzymatic treatment of NaCas to obtain enzymatic hydrolyzed NaCas(Eh NaCas),and the optimized conditions were 50℃,trypsin: NaCas= 1: 60(w/w),and the reaction was carried out for 6 h.Subsequently,characterization experiments such as SDS-PAGE,DLS analysis,hydrophobicity of protein surface and degree of enzymatic digestion were performed on Eh NaCas,which showed that Eh NaCas has smaller molecular weight,better hydrophilicity and higher degree of enzymatic digestion.2.TA-loaded Eh NaCas nanoparticles(Eh NaCas@TA)were prepared by self-assembly of TA with the hydrophobic region of Eh NaCas.At 37℃ and Eh NaCas: TA= 30: 1(w/w),Eh NaCas had a high encapsulation rate for TA.The results of TEM,FT-IR and XRD confirmed that TA was successfully trapped by the hydrophobic region of Eh NaCas;the results of DLS,solubility,stability(room temperature placement,high temperature,light and p H)showed that Eh NaCas@TA particles were small in size,high in solubility and high in solution stability;the results of antioxidant experiments showed that Eh NaCas and TA could exhibit synergistic antioxidant effects.3.Eh NaCas@TA could affect the growth of S.mutans with lower MIC,MBC values;the results of CLSM experiments indicated that Eh NaCas@TA disrupted the bacterial cell membrane and induced bacterial death.The results of crystalline violet(CV)biofilm staining,FESEM experiments showed that Eh NaCas@TA could disrupt biofilm structure and inhibit biofilm formation;bacterial surface hydrophobicity,aggregation and glycolytic activity experiments showed that Eh NaCas@TA limited the formation of S.mutans biofilm by affecting its composition mechanism.