Chen Zhou, Song Yanyin, Yan Yuhan, Wu Ziang, Xu Jiangqi
School of Food and Health, Beijing Technology and Business University, Beijing 100048, China.
J Agric Food Chem. 2025 Jun 25;73(25):15835-15846. doi: 10.1021/acs.jafc.5c02884. Epub 2025 Jun 11.
Sialyloligosaccharides, critical components of human milk oligosaccharides, are pivotal for infant immunity and development. Recent advances have identified sialidases with -sialylation activity as promising biocatalysts for cost-effective sialyloligosaccharide synthesis using economical substrates. Herein, we report a novel sialidase (Siase1) from sp. ALI-6-A with enhanced catalytic properties and broad substrate specificity, showing preferential hydrolysis: α2,3 > α2,6 > α2,8. The enzyme demonstrated robust -sialidase activity, achieving 3.40 g/L sialyloligosaccharide production using 0.5 U/mL Siase1, 6% lactose, and 8% cGMP. Implementing a direct-fed enzymatic strategy in raw milk with 1 U/mL Siase1 and 6% cGMP, we achieved in situ sialyloligosaccharide enrichment (2.49 g/L) while concomitantly reducing lactose. This biocatalytic system establishes a sustainable, scalable platform for functional food production, merging lactose valorization with sialyloligosaccharides biosynthesis through enzyme-substrate adaptability, addressing both industrial demands and nutritional needs in infant formula development.
唾液酸寡糖是人乳寡糖的关键成分，对婴儿免疫和发育至关重要。最近的进展已确定具有唾液酸化活性的唾液酸酶是有前景的生物催化剂，可使用经济的底物进行具有成本效益的唾液酸寡糖合成。在此，我们报道了一种来自 sp. ALI-6-A 的新型唾液酸酶（Siase1），其具有增强的催化特性和广泛的底物特异性，表现出优先水解：α2,3 > α2,6 > α2,8。该酶表现出强大的唾液酸酶活性，使用 0.5 U/mL Siase1、6% 乳糖和 8% 环鸟苷酸可实现 3.40 g/L 唾液酸寡糖的产量。在原料奶中采用 1 U/mL Siase1 和 6% 环鸟苷酸的直接添加酶策略，我们实现了原位唾液酸寡糖富集（2.49 g/L），同时降低了乳糖含量。这种生物催化系统通过酶 - 底物适应性将乳糖增值与唾液酸寡糖生物合成相结合，建立了一个可持续、可扩展的功能性食品生产平台，满足了婴儿配方奶粉开发中的工业需求和营养需求。
