Kiran Fadime, Mokrani Mohamed, Osmanagaoglu Ozlem
Department of Biology, Faculty of Science, Ankara University, Ankara, Turkey,
Curr Microbiol. 2015 Jul;71(1):95-105. doi: 10.1007/s00284-015-0832-8. Epub 2015 May 10.
The main goal of this study was to develop an improved oral delivery system for Pediococcus pentosaceus OZF, a promising probiotic bacterium, and to assess its viability under simulated gastrointestinal (GI) tract model by comparing the efficiency of microbiological and molecular approaches. Encapsulation was carried out using extrusion method and as a result, encapsulation system including 0.75 % lactulose, 1.8 % sodium alginate, 0.1 M CaCl2, and 5 min gelling time was shown to have a significantly protective effect against pH 2.0 acid stress over 3 h. However, completely loss of viability was exhibited by free OZF cells under similar conditions. To provide an additional barrier for capsules, coating process was investigated using different biopolymers, and the survival rates of free and encapsulated OZF cells upon expose to simulated GI conditions were detected by conventional culture techniques and propidium monoazide-quantitative polymerase chain reaction (PMA-qPCR) method. No significant differences between the biopolymers were detected, except the chitosan which leads totally 85 % protection and extra 25 % improvement in the survival of OZF cells compared to uncoated capsules. In conclusion, our findings indicated that chitosan-coated capsules provided an important protective effect on the viability of OZF cells against the GI system conditions encountered during the transit of food. In addition, this study was found successful in monitoring the viable OZF cells in capsules using PMA-qPCR method.
本研究的主要目标是为戊糖片球菌OZF（一种有前景的益生菌）开发一种改进的口服递送系统，并通过比较微生物学和分子方法的效率来评估其在模拟胃肠道（GI）模型下的生存能力。采用挤压法进行包封，结果表明，包含0.75%乳果糖、1.8%海藻酸钠、0.1 M氯化钙和5分钟凝胶化时间的包封系统在3小时内对pH 2.0的酸胁迫具有显著的保护作用。然而，在类似条件下，游离的OZF细胞完全丧失了生存能力。为了给胶囊提供额外的屏障，研究了使用不同生物聚合物的包衣过程，并通过传统培养技术和单叠氮碘化丙啶-定量聚合酶链反应（PMA-qPCR）方法检测游离和包封的OZF细胞在暴露于模拟胃肠道条件下的存活率。除壳聚糖外，未检测到生物聚合物之间的显著差异，与未包衣的胶囊相比，壳聚糖使OZF细胞的存活率提高了25%，总体保护率达到85%。总之，我们的研究结果表明，壳聚糖包衣的胶囊对OZF细胞在食物消化过程中遇到的胃肠道系统条件下的生存能力具有重要的保护作用。此外，本研究成功地使用PMA-qPCR方法监测了胶囊中存活的OZF细胞。
