Data and Supplementary Information from: Oligosaccharide Production Using β-galactosidase from <i>Lactobacillus bulgaricus</i> and <i>Kluyveromyces lactis</i> in Sweetened Reconstituted Nonfat Dry Milk

Supplementary information and raw data for the publication entitled "Oligosaccharide Production Using β-galactosidase from <i>Lactobacillus bulgaricus</i> and <i>Kluyveromyces lactis</i> in Sweetened Reconstituted Nonfat Dry Milk"ß-galactosidase (B-gal) is a vital enzyme used in the food industry to reduce lactose from dairy ingredients through hydrolysis and to synthesize galacto-oligosaccharides (GOS), a known bifidogenic prebiotic, from galactose through transgalactosylation. To favor transgalactosylation, high carbohydrate concentrations must be available to accept the galactose. Many dairy products rely on sweeteners for flavor and texture, but it is not known if high non-lactose sugar concentrations in milk can also favor transgalactosylation. B-gal from GRAS status Lactobacillus bulgaricus strains B548, LB11, YB1, or Kluyveromyces lactis (KL) in the commercial product Lactozyme® 2600L were used to determine if the transgalactosylation activity is greater in reconstituted nonfat dry milk (NDM, 10%, wt/wt) with commercial sweeteners compared to the transgalactosylation activity that occurs in unsweetened NDM at 50 °C for 20 h. Sucrose (14.4%, wt/wt), corn syrup solids (14.4%, wt/wt), or a mixture of sucrose (9.9%, wt/wt) and corn syrup solids (4.5%, wt/wt) were dissolved with NDM (n=3), then heated with stirring for 30 minutes at 70 °C for batch pasteurization. For L. bulgaricus, whole cells were inoculated at 7 log CFU/mL, or the same quantity of cells were lysed prior to adding to the milk and carbohydrate mixtures, or 1.85 U of KL B-gal was used. The sucrose mixture released the highest glucose from all whole cell, lysate, and KL enzyme preps, with LB11 lysate releasing the highest (245.57 ± 25.16 mM). High-Performance Anion-Exchange Chromatography with Pulsed Amperometric Detection was used to visualize the presence of oligosaccharides with degrees of polymerization of 3 to 7. Oligosaccharides from YB1 lysate treated sucrose mixtures also increased the anaerobic growth of Bifidobacterium breve 2141 at 37 °C compared to untreated or KL B-gal treated sucrose mixtures. B-gal treatment of sucrose in nonfat milk with and without corn syrup can be a source of prebiotic oligosaccharides, although more work is needed to determine if background microbiota are involved in hydrolyzing sucrose, and if fructose is also polymerizing to form novel oligosaccharides.

题为《加糖复原脱脂乳中利用保加利亚乳杆菌（*Lactobacillus bulgaricus*）和乳酸克鲁维酵母（*Kluyveromyces lactis*）来源β-半乳糖苷酶（β-galactosidase，简称β-gal）生产低聚糖》的论文的补充信息与原始数据。β-半乳糖苷酶是食品工业中的关键酶类，可通过水解作用降低乳制品原料中的乳糖含量，并通过转糖基化反应由半乳糖合成低聚半乳糖（galacto-oligosaccharides，GOS）——一类已被证实的促双歧杆菌增殖益生元。为促进转糖基化反应的进行，需提供高浓度的碳水化合物受体以结合半乳糖基团。多数乳制品依靠甜味剂调节风味与质地，但目前尚不明确牛乳中非乳糖类高浓度糖分是否同样可促进转糖基化反应。本研究使用具备一般认为安全（Generally Recognized As Safe，GRAS）资质的保加利亚乳杆菌菌株B548、LB11、YB1来源的β-半乳糖苷酶，以及商品化产品Lactozyme® 2600L中的乳酸克鲁维酵母（Kluyveromyces lactis，KL）来源β-半乳糖苷酶，以探究在添加商用甜味剂的复原脱脂乳（nonfat dry milk，NDM，10%，m/m）中，转糖基化活性是否高于未添加甜味的10%（m/m）复原脱脂乳体系（50 ℃反应20 h）中的转糖基化活性。将蔗糖（14.4%，m/m）、玉米糖浆固形物（14.4%，m/m）或蔗糖（9.9%，m/m）与玉米糖浆固形物（4.5%，m/m）的混合体系与复原脱脂乳混合（每组设置3个生物学重复，n=3），随后在70 ℃下搅拌加热30 min进行间歇巴氏灭菌。针对保加利亚乳杆菌来源的β-半乳糖苷酶，实验设置三种处理方式：以7 log 菌落形成单位（Colony Forming Unit，CFU）/mL的浓度接种完整菌体；将等量菌体裂解后再加入牛乳与碳水化合物混合体系；或直接添加1.85 U的乳酸克鲁维酵母来源β-半乳糖苷酶。在所有完整菌体、菌体裂解液以及乳酸克鲁维酵母酶制剂处理组中，蔗糖体系的葡萄糖释放量最高；其中LB11菌株裂解液处理组的葡萄糖释放量最高，达245.57 ± 25.16 mM。采用脉冲安培检测-高效阴离子交换色谱（High-Performance Anion-Exchange Chromatography with Pulsed Amperometric Detection）对聚合度为3~7的低聚糖进行定性检测。与未处理组或乳酸克鲁维酵母β-半乳糖苷酶处理的蔗糖体系相比，YB1菌株裂解液处理的蔗糖体系所产生的低聚糖，可在37 ℃厌氧条件下促进短双歧杆菌（Bifidobacterium breve）2141的生长。在脱脂乳中添加或不添加玉米糖浆的蔗糖体系经β-半乳糖苷酶处理后，可生成具备益生功能的低聚糖；但仍需进一步研究以明确：体系中本底菌群是否参与蔗糖水解，以及果糖是否也会发生聚合反应生成新型低聚糖。

搜集汇总

背景与挑战

背景概述

该数据集提供了关于使用Lactobacillus bulgaricus和Kluyveromyces lactis的β-半乳糖苷酶在加糖脱脂奶粉中生产低聚糖的补充信息和原始数据。研究比较了加糖与未加糖条件下酶的转半乳糖基化活性，发现蔗糖混合物能促进葡萄糖释放和低聚糖生成，这些低聚糖具有益生元潜力，可支持双歧杆菌生长。数据集适用于食品科学和酶工程领域的研究，关注低聚糖合成和功能性食品开发。