食品工业科技2025，Vol.46Issue(6)：170-178,9.DOI:10.13386/j.issn1002-0306.2024030252
源于奶酪的产β-半乳糖苷酶乳酸片球菌的筛选及其合成低聚半乳糖特性
Screening of A β-Galactosidase-producing Pediococcus acidilactici Strain from Cheese and Its Characteristics for Galactooligosaccharides Synthesis
摘要
Abstract
This study aimed to provide a new lactic acid bacteria(LAB)enzyme source for synthesizing probiotic galactooligosaccharides(GOS).It screened β-galactosidase producing strains with high transglycosidase activity from traditional cheese in Xinjiang,China.A modified MRS medium with lactose as the single carbon source supplemented with 5-bromo-4-chloro-3-indole-β-D-galactoside was used for the first-round screening of LAB strains producing β-galactosidases.Thin layer chromatography(TLC)analysis of the reaction products catalyzed by the crude enzyme from selected strains was used for the second-round screening.The isolate with the highest transglycosylation activity was identified based on the physiological and biochemical characteristics,along with the sequence analysis of the 16S rRNA gene.The conditions for enzyme production and transglycosylation reaction were determined by one-way experiment.TLC combined with high performance liquid chromatography was conducted to analyze the content of each GOS component.Six strains producing β-galactosidase with transglycosidase activity were screened,among which Pediococcus acidilactici Y1 exhibited the highest enzyme production level and transglycosidase activity.After optimization,P.acidilactici Y1 producedβ-galactosidase at a level of up to 15.52±0.34 U/g(with 20 mg/mL of initial lactose after 18 h at 37 ℃).The highest GOS yield of 38.4％±0.56％(w/w)was achieved with an initial lactose concentration of 300 mg/mL,an enzyme amount of 4.24 U/mL,and a reaction temperature of 50 ℃ for 28 h.Also,the residual rate of lactose decreased to 30.9％±0.44％(w/w).The content of transfer disaccharide,transfer trisaccharide,and transfer trisaccharide was 15.6％±0.21％(w/w),18.3％±0.15％(w/w),and 4.5％±0.01％(w/w),respectively.The results of this study showed that P.acidilactici Y1 was a new β-galactosidase-producing strain,with application prospects in the synthesis of probiotic GOS.关键词
β-半乳糖苷酶/转糖苷活性/低聚半乳糖/乳酸片球菌/奶酪Key words
β-galactosidase/transglycosylation activity/galactooligosaccharides/Pediococcus acidilactici/cheese分类
生物科学引用本文复制引用
李欣,张秋涵,马子尧,关波,胡有贞,李谞,倪永清..源于奶酪的产β-半乳糖苷酶乳酸片球菌的筛选及其合成低聚半乳糖特性[J].食品工业科技,2025,46(6):170-178,9.基金项目
国家自然科学基金(32060522) （32060522）
兵团科技创新人才计划青年拔尖人才项目(2024DB028) （2024DB028）
石河子大学成果转化与技术推广计划(CGZH202305). （CGZH202305）
