改性海藻酸钠微胶囊的制备及毒性研究

以改性海藻酸钠（聚丙烯酸钠接枝海藻酸钠）作为新型的乳酸菌微胶囊壁材，研究改性海藻酸钠的毒性和对多种乳酸菌的包埋效果。结果显示，该材料对大鼠无急性毒性，且对组织细胞亦无明显毒性，可安全食用；与海藻酸钠相比，该材料制备的微胶囊结构更为紧致，有助于阻隔多种不利因素对乳酸菌活性的影响，同时提高了对植物乳杆菌MA2、嗜酸乳杆菌563和乳酸乳球菌WH-C1的包埋率（分别提高4.5%、4.4%和7.1%），降低了粒径（分别降低0.34 cm、0.26 cm和0.21 cm）。因此，该材料有望成为一种安全、有效的乳酸菌微胶囊壁材。

Preparation and toxicity test of modified alginate microcapsule

Modified alginate (sodium polyacrylate grafted alginate, Alg-PAAs) was used as noval microencapsulation wall material, and the toxicity of the modified alginate and encapsulation effect to lactic acid bacteria were evaluated. The results showed that the polymer that had no acute toxicity to rat and no significant toxicity to tissue cells was edible; compared with alginate, the microcapsule made of the modified alginate was denser which was good for protecting lactic acid bacteria against various adverse factors. At the same time, the encapsulation efficiency of Lactobacillus plantarum MA2, Lactobacillus acidophilus 563 and Lactococcus lactis WH-C1 microcapsules were improved (by 4.5%, 4.4% and 7.1%, respectively), and particle sizes were decreased (by 0.34, 0.26 and 0.21 cm, respectively). Therefore, the modified alginate could be a potentially safe and effective wall material in lactic acid bacteria microcapsulation.