Abstract In present study, a combination of biopolymers soy protein isolate (SPI) and sugar beet pectin (SBP) has been used to prepare an interpenetrating polymer network (IPN) hydrogel by enzymatic method. The obtained results showed that the rheological properties, textural properties and swelling properties could be tuned by regulating the concentrations of SPI and SBP as well as the amount of laccase. Moreover, the incorporation of probiotic Lactobacillus paracasei LS14 resulted in a decrease of storage modulus (G′) and hardness of SPI/SBP IPN gels. The reason might be that the addition of probiotics caused the exposure of tryptophan-containing extension regions within SPI molecules to a more polar environment. In addition, the occurrence of steric-hindrance effect of probiotic cells during the gelation of IPN hydrogels retarded the formation of covalent cross-links or physical interactions between biopolymer molecules. Scanning electron microscopy (SEM) observation confirmed that the presence of probiotics slightly disrupted the ordered microstructure of the IPN hydrogel. Under simulated gastrointestinal conditions, the SPI/SBP IPN gel showed its advantage in protection of Lb. paracasei LS14 since it had higher viabilities of probiotic cells as compared to free cells. In addition, lyophilized gels exhibited better storage stability but lower probiotic viability in comparison to wet gels. Overall, this study explored a novel method for the production of SPI/SBP IPN gel as a delivery system for probiotics, which would have great potential for development of probiotic-containing foods.

中文翻译：

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大豆分离蛋白和甜菜果胶的互穿聚合物网络水凝胶作为益生菌的潜在载体

摘要 在目前的研究中，生物聚合物大豆分离蛋白 (SPI) 和甜菜果胶 (SBP) 的组合已被用于通过酶法制备互穿聚合物网络 (IPN) 水凝胶。所得结果表明，可以通过调节 SPI 和 SBP 的浓度以及漆酶的量来调节流变特性、质构特性和溶胀特性。此外，益生菌副干酪乳杆菌 LS14 的掺入导致 SPI/SBP IPN 凝胶的储能模量 (G') 和硬度降低。原因可能是益生菌的添加导致 SPI 分子内含色氨酸的延伸区域暴露于更极性的环境中。此外，在 IPN 水凝胶凝胶化过程中，益生菌细胞空间位阻效应的发生阻碍了生物聚合物分子之间共价交联或物理相互作用的形成。扫描电子显微镜 (SEM) 观察证实，益生菌的存在略微破坏了 IPN 水凝胶的有序微观结构。在模拟胃肠道条件下，SPI/SBP IPN凝胶显示出其在保护Lb方面的优势。paracasei LS14，因为与游离细胞相比，它具有更高的益生菌细胞活力。此外，与湿凝胶相比，冻干凝胶表现出更好的储存稳定性，但益生菌活力较低。总的来说，这项研究探索了一种生产 SPI/SBP IPN 凝胶作为益生菌输送系统的新方法，