Construction And Application Of Peanut Protein Isolate-curcumin Nanocomplexes

Curcumin(Cur)is a polyphenolic compound that was first isolated from the roots of Zingiberaceae turmeric in 1870.It has a wide range of pharmacological activities such as anti-oxidation,anti-bacterial,anti-aging,anti-inflammatory,anti-tumor;However,curcumim exist extremely difficult to dissolve in water,has poor photothermal stability,and it is easily deactivated under acid-base conditions,has shortcomings such as fast metabolism and low bioavailability in the body,and it is greatly restricted in both food and medicine.In this study,peanut protein isolate and curcumin were used to form peanut protein isolate-curcumin nanocomplexes through intermolecular interaction,and then peanut protein isolate-curcumin/arrageenan complex were formed with carrageenan,and then gelatin hybrid film containing composite were formed with film-forming matrix gelatin.Research on curcumin iproving water solubility,physicochemical stability,antioxidant and antibacterial properties.The research method and result of this paper are as follows:(1)In this study,peanut protein isolate(PPI)was extracted by alkali-soluble acid precipitation method,and the protein content of peanut protein isolate was(92.13±1.42)%;The peanut protein isolate-curcumin nanocomplexes was prepared by the alkali reaction acid neutralization and water bath heating assisted method,drug loading as an indicator,the optimal preparation process was determined by orthogonal design,the peanut protein isolate:curcumin 10:1(W/W),water bath temperature 45 0C,water bath time at 25 min,the drug loading of the nanocomplexes was(7.93± 0.166)%,the particle size was(164.3±6.5)nm,and the PDI was 0.238±0.014;Through investigation of the solubility of nanocomplexes,the solubility of curcumin in nanocomplexes increased by 1109 times compared with curcumin drug;Through investigation of the physical and chemical stability of nanocomplexes,the nanocomplexes have a certain degree of improvement in physicochemical stability compared with curcumin drug;Characterization of nanocomplexes by UV,fluorescence and FT-IR,showing that peanut protein isolate and curcumin were recombined by hydrophobic interaction and hydrogen bonding;The differential scanning thermogram showed that curcumin was combined with peanut protein isolate,curcumin existed in an amorphous form;Through investigation of the release of nanocomplexes,the release of curcumin in nanocomplexes was accelerated compared to the curcumin drug;Through investigation of the antioxidative activity of nanocomplexes,DPPH free radicals and ABTS+clearance rate of the nanocomplexes are significantly improved compared with curcumin drug;Through investigation of the antibacterial activity of the nanocomplexes,the antibacterial and bactericidal effect of the nanocomplexes is better than that of the curcumin drug(2)In order to further improve the physicochemical stability of curcumin and improve the anti-oxidative and antibacterial activity of curcumin,the peanut protein isolate-curcumin nanocomplexes and kappa-carrageenan(CG)form a peanut protein isolate-curcumin/carrageenan complex.By studying the physicochemical stability of the peanut protein isolate-curcumin/carrageenan complex,the peanut protein isolate-curcumin/carrageenan complex has a certain improvement in physicochemical stability compared to the nanocomplexes.Through the investigation of release of peanut protein-curcumin/carrageenan complex,it was found that the release of peanut protein-curcumin/carrageenan complex is higher than that of curcumin drug.which is lower than that of nanocomplexes.Through the investigation of the antioxidant activity of the peanut protein isolate-curcumin/carrageenan complex,the DPPH free radical and ABTS+clearance rate of the peanut protein isolate-curcumin/carrageenan complex was slightly improved compared with the nanocomplexes.Through the investigation of antibacterial activity of the peanut protein isolate-curcumin/carrageenan composite object,the antibacterial and bactericidal effect of the peanut protein isolate-curcumin/carrageenan complex is better than that of the nanocomplexes(3)Peanut protein isolate-curcumin/carrageenan complex and gelatin(Gel)are prepared by casting method gelatin hybrid film containing composite.Through the investigation of the basic properties of gelatin hybrid film containing composite,it was found that the gelatin hybrid film containing composite had reduced moisture content,increased water solubility,reduced water vapor migration rate,increased barrier properties,and certain curcumin and peanut protein isolates-curcumin/carrageenan complex concentration dependence.Through the investigation of the antioxidant activity of the gelatin hybrid film containing composite,the gelatin hybrid film containing composite has higher DPPH free radical,ABTS+ clearance rate,better antioxidant activity and certain curcumin and peanut protein isolate-curcumin/carrageenan complex concentration dependence.The invitro antibacterial activity of the composite gelatin hybrid film-forming solution was investigated.It was found that the gelatin hybrid film containing composite had good antibacterial activity and certain concentration dependence of curcumin and peanut protein isolate-curcumin/carrageenan complex.Through the contact antibacterial activity of the gelatin hybrid film containing composite,it was found that there was no bacterial growth in contact with the gelatin hybrid film containing composite.Compared with the blank control,some bacteria were not in contact with the gelatin hybrid film containing composite.It is reduced and has a certain concentration dependence of curcumin and peanut protein isolate-curcumin/carrageenan complex,but the reduction of bacteria is not obvious,which is related to the difficulty in the diffusion of curcumin in agar containing hybrid gelatin.