海藻酸钠微囊化JS25噬菌体的制备、表征及其在食品模拟体系中的释放

通过海藻酸钠微囊化JS25噬菌体，并对制备的JS25噬菌体微囊粉进行结构表征和稳定性分析，通过构建不同的食品模拟体系分析JS25噬菌体微囊粉的释放规律。结果表明，海藻酸钠和CaCl2组成的体系能有效地构建JS25噬菌体微囊粉，通过响应面优化试验得到海藻酸钠和CaCl2添加量分别为3.72、2.55?g/100?mL时，JS25噬菌体包埋率可达88.38%；该条件下的JS25微囊粉粒径分布在20～90?μm之间，且呈正态分布；并且与浮游态噬菌体相比，微囊化的JS25噬菌体稳定性显著增加至35?d（4?℃和20?℃）。另外，JS25微囊粉在不同食品模拟体系中均可迅速释放，呈现先增加后稳定的趋势，在8?min后释放率均达75%以上。说明该工艺可以有效固定JS25噬菌体，并且对噬菌体效价影响较小。因此，海藻酸钠微囊化JS25噬菌体可以用于JS25噬菌体微囊粉的生产加工。

Preparation,Characterization and Release Characteristics in Food Simulant Systems of Sodium Alginate Microcapsules Containing Phage JS25

In this experiment, phage JS25 was microencapsulated with sodium alginate, and the structure of the microcapsule powder was characterized in order to determine its size distribution. In addition, the stability at different temperatures was analyzed by using planktonic phage as a control. The release characteristics of microencapsulated phage in four different food simulant systems were evaluated as well. The results showed that the phage was effectively microencapsulated with sodium alginate and CaCl2. The results of optimization by response surface methodology (RSM) indicated that the maximum microencapsulation efficiency of 88.38% was obtained when the concentrations of sodium alginate and CaCl2 were 3.72 and 2.55 g/100 mL, respectively. The size of the prepared microcapsules showed a normal distribution in the range of 20–90 μm. The microcapsules were stable for 35 d at 4 and 20 ℃, having improved stability compared with the control. The phage microcapsule powder was rapidly released in the tested food simulation systems and the release rate increased and then remained stable, reaching higher than 75% at 8 min. Therefore, this process can be used for microencapsulation of phage JS25 to improve its stability with little impact on its titer.