Lens culinaris β-galactosidase (Lsbgal): Insights into its purification, biochemical characterization and trisaccharides synthesis

A GH42 β‐galactosidase from Bifidobacterium thermophilum: Biochemical characterization and synthesis of galactosyl glycerol by reverse hydrolysis

“…Detergents, Triton X‐100 and Tween 80, were shown to reduce the enzymatic activity by 12 and 25%, respectively, which might be due to the disaggregation of the homotrimeric BtGal42. Similar observations were also reported on L. culinaris β‐galactosidase Lsbgal, 45 and B. velezensis phospho‐β‐galactosidase Gal1332 47 BtGal42 was significantly inhibited by SDS and cetyl trimethyl ammonium bromide (CTAB), indicating that its activity was depended on disulfide bonds. This result was contrary to the finding of β‐galactosidases from B. velezensis 41 and L. leichmanii 313 11 …”

“…Besides, the catalytic efficiency ( K m /k cat of BtGal42 for o NPG was 242.1 s −1 mM −1 , which was higher than that reported for β‐galactosidases from B. velezensis (101.7 s −1 mM −1 ), 41 K. oxytoca ZJUH1705 (38.8 s −1 mM −1 and 7.4 s −1 mM −1 ), 17 and P. torridus (27.4 s −1 mM −1 ) 39 . The activation energy (Ea) of BtGal42 for the hydrolysis of o NPG was 7.4 kJ/mol, which was lower than that of β‐galactosidases from B. animalis BL‐04 (13.8 kJ/mol) 36 and L. culinaris (8.1 kJ/mol) 45 . The latter two enzymes had higher K m values compared with BtGal42, indicating that the high affinity of BtGal42 might led to the low Ea for o NPG hydrolysis.…”

“…The specific activity of BtGal42 under optimum conditions with o NPG as the substrate was 180 U/mg, which was similar to that of β‐galactosidases from Anthrobacter sp. 20B (156 U/mg), 37 B. velezensis SW5 (147 U/mg), 42 K. oxytoca ZJUH1705 (217 U/mg), 17 and B. longum 15708 (168 U/mg), 44 whereas it was remarkably lower than the specific activity exhibited by β‐galactosidases from other Bifidobacterium species, such as B. bifidum (1506 U/mg), 32 B. breve B24 (8073 U/mg), 35 B. animalis (2351 U/mg), 45 and B. adolescentis (526 U/mg) 43 . However, the ability of these enzymes to catalyze reverse hydrolysis has not been reported.…”

“…39 The activation energy (Ea) of BtGal42 for the hydrolysis of oNPG was 7.4 kJ/mol, which was lower than that of βgalactosidases from B. animalis BL-04 (13.8 kJ/mol) 36 and L. culinaris (8.1 kJ/mol). 45 The latter two enzymes had higher K m values compared with BtGal42, indicating that the high affinity of BtGal42 might led to the low Ea for oNPG hydrolysis.…”

Production of Prebiotic Galacto-Oligosaccharides from Acid Whey Catalyzed by a Novel β-Galactosidase from Thermothielavioides terrestris and Commercial Lactases: A Comparative Study

“…The more thermostable β-galactosidases from T. thermophilus (optimum temperature 65 • C) and P. furiosus (optimum temperature 90 • C) exhibited significantly lower N-acetyllactosamine yields, reaching only up to 16% and 5.4%, respectively. Additionally, Yadav and Kayastha (2020) studied the transgalactosylation activity of β-galactosidase from Lens culinaris, using pure lactose solutions (200 g/L) as a substrate and reported a maximum GOS concentration of 68 g/L, after 16 h of enzymatic reaction at 55 • C and pH = 4.5, using 12 U/mL enzyme load [31]. This GOS concentration corresponds to a 34% GOS yield, which is slightly higher than the 31.3 ± 0.4% maximum GOS yield achieved in the present study using β-galactosidase from T. terrestris in acid whey, under almost identical reaction conditions.…”