复配益生元微胶囊的制备及其消化耐受性

Preparation and Digestive Tolerance of Compound Prebiotic Microcapsules

为提高植物乳杆菌的肠胃液耐受以及释放性能,该文以植物乳杆菌和不同质量比的益生元(菊粉、黄精多糖)为芯材,海藻酸钠和壳聚糖为壁材,采用挤压法制备合生元微胶囊。通过单因素和正交试验确定微胶囊最佳制备工艺条件,并以包埋率、存活率、储存稳定性、肠胃液耐受性及释放速率为评定指标,对合生元微胶囊最佳配比进行研究。结果表明,不同质量比的益生元对植物乳杆菌均有协同生长的作用;通过正交试验得出制备微胶囊最佳工艺条件为海藻酸钠浓度2%、CaCl2浓度0.3 mol/L、壳聚糖浓度0.8%、固化时间3 h,该条件下未添加益生元的微胶囊包埋率达到80.44%,菊粉和黄精多糖的质量比为2∶3时的包埋率最高,达到92.61%,冻干后的存活率也最高,达到81.44%;通过体外模拟胃肠道发现,包埋后的合生元微胶囊对植物乳杆菌有明显的保护效果,在连续胃肠液模拟实验中,植物乳杆菌菌液数量级下降7.36 lg(cfu/mL),而微胶囊活菌数最大降幅为1.81 lg(cfu/mL),其中菊粉和黄精多糖质量比为2∶3时,微胶囊在胃液中的存活率和肠液中的释放率均达到最高,该质量比下的合生元微胶囊具有最优的肠胃液释放性能。

To improve the tolerance to gastrointestinal fluid and release performance of Lactobacillus plantarum,synbiotic microcapsules were prepared by extrusion method with L. plantarum and prebiotics(inulin and Polygonatum polysaccharide)at different mass ratios as the core materials and sodium alginate and chitosan as the wall materials. The optimal preparation conditions of the microcapsules were determined by single factor and orthogonal experiments with the embedding rate,survival rate,storage stability,tolerance to gastrointestinal fluid,and release rate as evaluation indicators. The results showed that the prebiotics at different mass ratios all had synergistic effect on the growth of L. plantarum. The preparation conditions of the microcapsules were optimized as sodium alginate of 2%,CaCl2of 0.3 mol/L,chitosan of 0.8%,and curing for 3 h. Under these conditions,the embedding rate of the microcapsules without prebiotics reached 80.44%. When the mass ratio of inulin to Polygonatum polysaccharide was 2 ∶ 3,the embedding rate was the highest(92.61%),and the survival rate of L. plantarum after freeze-drying was also the highest,reaching 81.44%. The experiment with simulated gastrointestinal tract in vitro showed that the embedded synbiotic microcapsules had a significant protective effect on L. plantarum. In the continuous gastrointestinal fluid simulation experiment,the viable count of L.plantarum in the suspension dropped by 7.36 lg(cfu/mL),while that in the microcapsules by 1.81 lg(cfu/mL)to the maximum. When the mass ratio of inulin to Polygonatum polysaccharide was 2 ∶ 3,the survival rate of L.plantarum in gastric fluid and the release rate in intestinal fluid peaked,which indicated that the synbiotic microcapsules prepared with this mass ratio had the best release performance in gastrointestinal fluid.