Study On The Preparation Of Curcumin Microcapsules And Its Intervention Effect On Diarrhea And Colitis In Mice

Curcumin is a natural antioxidant and anti-inflammatory agent that exhibits good biological activity and beneficial pharmacological effects.Studies have shown that curcumin is effective and safe when used in the prevention and treatment of intestinal diseases,but its poor stability and low water-solubility limit its application.Microencapsulation is an effective method with which to improve the stability of curcumin.In the present research,curcumin microcapsules were prepared by way of the sharp-hole method using sodium alginate,sponge rubber fungus polysaccharides,and calcium chloride as composite wall materials.Single factor and orthogonal experimental designs were used to optimize the preparation of curcumin microcapsules.The optimized process was described as follows:sodium alginate 2.5%,curcumin 0.4%,Tween 80 0.3%,entrapment time 1.5 h,CaCl₂2.0%,and Scorias spongiosa polysaccharides 0.15%.The rate of embedding of curcumin microcapsules was 92.26%,and the drug loading was 20.56%.The structure of curcumin microcapsules was characterized by scanning electron microscopy,laser particle size analysis,Fourier transform infrared spectroscopy,and other equipment:the effect on the preparation of curcumin microcapsules was investigated.The electron micrographs showed that curcumin could be embedded by sharp-hole method,and the microcapsules were full and intact;the results of particle size analysis indicated that the average particle size of the microcapsules was 432.19μm,and the results of Fourier transform infrared spectroscopy showed that the Scorias spongiosa polysaccharides were present in the composite microcapsules as evinced by the hydrogen bonding force.Curcumin was embedded in the microcapsule by chemical bonding force.The results of X-ray diffraction analysis demonstrated that the crystal structure of curcumin in curcumin microcapsules changed after embedment,and the results of differential scanning calorimetry and thermogravimetric analysis showed that the structure of curcumin microcapsules was more stable after adding Scorias spongiosa polysaccharides.The thermal stability also increased.The efficacy and mechanism of curcumin microcapsules were evaluated with the help of the mouse diarrhea model.Senna leaf,castor oil,and magnesium sulfate were used to construct mouse diarrhea models,and stable diarrhea models were selected.The diarrhea model induced by a high dose of Senna leaf was selected to assess the effect of curcumin microcapsules on mice.The results proved that curcumin microcapsules could effectively interfere with diarrhea induced by Senna leaves,reduce the diarrhea index,regulate inflammatory response through the TLR4/NF-κB pathway,enhance intestinal antioxidant activity of mice through the Nrf2 signal pathway,then up-regulate intestinal tight junction protein to maintain the intestinal barrier,and achieve intervention effect on diarrhea mice under the combined action of antioxidation,maintenance of intestinal barrier,and anti-inflammation.The mouse colitis model induced by Dextran sulfate sodium（DSS）was used to evaluate the efficacy and mechanism of action of curcumin microcapsules.The results implied that curcumin microcapsules could effectively interfere with DSS-induced colitis in mice.Curcumin microcapsules could regulate the NF-κB-STAT1-MAPK signal pathway,reshape intestinal microflora,maintain the integrity of the intestinal barrier,induce oxidation ability and balance its effects in the mouse colitis model,and achieve an intervention effect on colitis mice.