Kittibunchakul Suwapat, van Leeuwen Sander S, Dijkhuizen Lubbert, Haltrich Dietmar, Nguyen Thu-Ha
Food Biotechnology Laboratory, Department of Food Science and Technology, BOKU-University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, A-1190 Vienna, Austria.
Institute of Nutrition, Mahidol University, 999 Phutthamonthon 4 Road Salaya, Nakhon Pathom 73170, Thailand.
J Agric Food Chem. 2020 Apr 15;68(15):4437-4446. doi: 10.1021/acs.jafc.9b08156. Epub 2020 Apr 6.
The LacLM-type β-galactosidase from DSM 20075 expressed in both (β-gal) and (β-gal) was tested for their potential to form galacto-oligosaccharides (GOS) from lactose. The Lh-GOS mixture formed by β-galactosidase from , together with three GOS mixtures produced using β-galactosidases of both the LacLM and the LacZ type from other lactic acid bacteria, namely, (Lr-GOS), (Lb-GOS), and (St-GOS), as well as two GOS mixtures (Br-GOS1 and Br-GOS2) produced using β-galactosidases (β-gal I and β-gal II) from , was analyzed and structurally compared with commercial GOS mixtures analyzed in previous work (Vivinal GOS, GOS I, GOS III, and GOS V) using high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD), high-performance size-exclusion chromatography with a refractive index (RI) detector (HPSEC-RI), and one-dimensional H NMR spectroscopy. β-Galactosidases from lactic acid bacteria and displayed a preference to form β-(1→6)- and β-(1→3)-linked GOS. The GOS mixtures produced by these enzymes consisted of mainly DP2 and DP3 oligosaccharides, accounting for ∼90% of all GOS components. GOS mixtures obtained with β-galactosidases from lactic acid bacteria and were quite similar to the commercial GOS III mixture in terms of product spectrum and showed a broader product spectrum than the commercial GOS V mixture. These GOS mixtures also contained a number of GOS components that were absent in the commercial Vivinal GOS (V-GOS).
对来自DSM 20075且在(β - gal)和(β - gal)中均有表达的LacLM型β - 半乳糖苷酶，测试了其从乳糖形成低聚半乳糖（GOS）的潜力。由的β - 半乳糖苷酶形成的Lh - GOS混合物，与使用其他乳酸菌的LacLM型和LacZ型β - 半乳糖苷酶产生的三种GOS混合物，即（Lr - GOS）、（Lb - GOS）和（St - GOS），以及使用的β - 半乳糖苷酶（β - gal I和β - gal II）产生的两种GOS混合物（Br - GOS1和Br - GOS2），使用带脉冲安培检测的高效阴离子交换色谱法（HPAEC - PAD）、带示差折光检测器的高效尺寸排阻色谱法（HPSEC - RI）和一维H NMR光谱法进行了分析，并与先前工作中分析的商业GOS混合物（Vivinal GOS、GOS I、GOS III和GOS V）进行了结构比较。来自乳酸菌和的β - 半乳糖苷酶表现出形成β - (1→6) - 和β - (1→3) - 连接的GOS的偏好。这些酶产生的GOS混合物主要由二糖（DP2）和三糖（DP3）低聚糖组成，占所有GOS组分的约90%。在产物谱方面，用乳酸菌和的β - 半乳糖苷酶获得的GOS混合物与商业GOS III混合物非常相似，并且比商业GOS V混合物显示出更宽的产物谱。这些GOS混合物还包含许多商业Vivinal GOS（V - GOS）中不存在的GOS组分。
