Food Ingredients and Biopolymers Laboratory, Department of Plant Sciences, North Dakota State University, Fargo, ND 58108, USA.
Edward T. Schafer Agricultural Research Center, Cereal Crops Research Unit, Hard Spring and Durum Wheat Quality Lab, USDA-ARS, Fargo, North Dakota 58108, USA.
Soft Matter. 2020 Feb 19;16(7):1877-1887. doi: 10.1039/c9sm02387a.
Sodium alginate hydrogel particles coated with cationic biopolymers have been shown to be one of the promising means for probiotic encapsulation and protection. In this study, we aimed to systematically explore the effect of molecular weight of chitosan coating on the functional performance of sodium alginate hydrogel particles for improving the viability of Lactobacillus rhamnosus GG (LGG). We first electrostatically deposited three different molecular weights of chitosan coatings, i.e., chitosan oligosaccharide (COS), low molecular weight chitosan (LMW-chitosan) and medium molecular weight chitosan (MMW-chitosan) on sodium alginate hydrogel particles. Both SEM and FTIR results indicated that chitosan was successfully deposited onto the surface of the hydrogel particles. We then evaluated the effect of chitosan MW on the viability of LGG encapsulated in the hydrogels during long-term storage and simulated gastrointestinal digestion. Among them, the hydrogel particles coated with COS prevented the viability loss of LLG during long-term storage at different temperatures (4, 25 and 37 °C). However, we did not find any improvement in the viability of the encapsulated LGG by all three chitosan coatings during simulated digestion.
用带正电荷的生物聚合物涂覆的海藻酸钠水凝胶颗粒已被证明是益生菌包封和保护的有前途的方法之一。在这项研究中，我们旨在系统地探索壳聚糖涂层的分子量对提高鼠李糖乳杆菌 GG（LGG）活力的海藻酸钠水凝胶颗粒的功能性能的影响。我们首先通过静电沉积三种不同分子量的壳聚糖涂层，即壳寡糖（COS）、低分子量壳聚糖（LMW-chitosan）和中分子量壳聚糖（MMW-chitosan）于海藻酸钠水凝胶颗粒上。SEM 和 FTIR 结果均表明壳聚糖成功沉积在水凝胶颗粒表面。然后，我们评估了壳聚糖 MW 对水凝胶中包封的 LGG 在长期储存和模拟胃肠道消化过程中的存活率的影响。其中，COS 涂层的水凝胶颗粒在不同温度（4、25 和 37°C）下的长期储存过程中防止了 LLG 的存活率下降。然而，我们没有发现三种壳聚糖涂层在模拟消化过程中对包封的 LGG 的存活率有任何提高。
