Beta-galactosidase, phospho-beta-galactosidase and phospho-beta-glucosidase activities in lactobacilli strains isolated from human faeces.
OBJECTIVE
Lactose intolerance, a serious health problem for Asians, can be solved using probiotic bacteria having high lactose hydrolysis activities. We determined the distribution of beta-galactosidase (beta-gal), phospho-beta-galactosidase (P-betagal) and phospho-beta-glucosidase (P-beta-glc) activities in species of lactic acid bacteria (LAB) isolated from human faeces to select strains for potential use in fermented dairy products, e.g. yogurt.


RESULTS
The sugar substrates, o-nitrophenyl-beta-D- galactopyranoside 6-phosphate and o-nitrophenyl-beta-D-glucopyranoside 6-phosphate, were synthesized and used to measure respectively P-beta-gal and P-beta-glc activities. Sixty-five toluene-treated strains were examined for three lactase enzyme activities. Lactobacillus mucosae OLL2848 showed the highest beta-gal activity (107.09 U mg(-1) of protein) among the Lactobacillus strains from human faeces. Lactobacillus gasseri OLL2836 and OLL 2948 showed the highest P-beta-gal (46.58 U) and P-beta-glc (50.19 U)activity, respectively, with no beta-gal activity.


CONCLUSIONS
The expression of P-beta-glc induced by lactose was characteristic of Lact. gasseri. Because this LAB is a major inhabitant of the human intestine. This enzyme is a key glycosidase involved in lactose utilization.


CONCLUSIONS
This is the first report describing the distribution of three glycosidase activities used in lactose metabolism in LAB isolated from human faeces for possible use in functional foods.
Honda
H
H
Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai, Japan.
Kataoka
F
F
Nagaoka
S
S
Kawai
Y
Y
Kitazawa
H
H
Itoh
H
H
Kimura
K
K
Taketomo
N
N
Yamazaki
Y
Y
Tateno
Y
Y
Saito
T
T
D001426:Bacterial Proteins / Q000032:analysis*; D005243:Feces / Q000382:microbiology*; D006801:Humans; D007778:Lactobacillus / Q000201:enzymology* / Q000302:isolation & purification; D001616:beta-Galactosidase / Q000032:analysis*; D001617:beta-Glucosidase / Q000032:analysis*
D001426:Bacterial Proteins; D001617:beta-Glucosidase; D001616:beta-Galactosidase