Isolation and characterization of β-galactosidase fromLactobacillus crispatus

Abstract

beta-Galactosidase was isolated from the cell-free extracts of Lactobacillus crispatus strain ATCC 33820 and the effects of temperature, pH, sugars and monovalent and divalent cations on the activity of the enzyme were examined. L. crispatus produced the maximum amount of enzyme when grown in MRS medium containing galactose (as carbon source) at 37 degrees C and pH 6.5 for 2 d, addition of glucose repressing enzyme production. Addition of lactose to the growth medium containing galactose inhibited the enzyme synthesis. The enzyme was active between 20 and 60 degrees C and in the pH range of 4-9. However, the optimum enzyme activity was at 45 degrees C and pH 6.5. The enzyme was stable up to 45 degrees C when incubated at various temperatures for 15 min at pH 6.5. When the enzyme was exposed to various pH values at 45 degrees C for 1 h, it retained the original activity over the pH range of 6.0-7.0. Presence of divalent cations, such as Fe2+ and Mn2+, in the reaction mixture increased enzyme activity, whereas Zn2+ was inhibitory. The Km was 1.16 mmol/L for 2-nitrophenyl-beta-D-galactopyranose and 14.2 mmol/L for lactose.

Transgalactosylating β-galactosidase from probiotic Lactobacillus plantarum MCC2156: production and permeabilization for use as whole cell biocatalyst

“…3) and the optimum was found to be 4, 2 and 3 % (w/v), respectively, and a further increase in concentration of all these components did not significantly (p<0.05) affect the β-galactosidase production. The role of carbon source on the induction of β-galactosidase production vary among microorganism and in our previous study, β-galactosidase production by L. plantarum MCC2156 was highest when galactose was used as carbon source (Gobinath and Prapulla 2014) which is in accordance with other reports (Kim and Rajagopal 2000;Laxmi et al 2011). Not only the type of carbon source, but also the concentration of the chosen carbon source plays an important role in β-galactosidase production by microorganisms (Fiedurek and Szczodrak 1994;Inchaurrondo et al Different alphabets above each concentration indicate significant difference (p<0.05) 1998).…”

A Potent Probiotic Strain from Cheddar Cheese

“…Lactose is considered to be the best carbon source to induce maximum b-galactosidase by K. fragiles [35], B. coagulans [36] and B. longum CCRC 15708 [37] whereas in the case of L. crispatus, highest b-galactosidase activity is observed in the presence of galactose [38]. In the present study highest enzyme activity was observed in presence of lactose.…”

Selection of lactic acid bacteria strain for simultaneous production of α- and β-galactosidases

“…There are numerous reports on significant effects of utilized carbon sources of galactosidases [16,49,50]. However, these findings are not universal, and depend greatly on the nature of producer.…”