Abstract:
In this study, the milk-derived Galactooligosacchar
ides (GOS) were produced by
Lactobacillus delbrueckii subsp. bulgaricus
and refined by an ultrafiltration-nanofiltration
continuous membrane. By further investigation, we f
ound that the GOS product purified
by gel permeation chromatography mainly contained l
ow molecular weight disaccharide
and trisaccharide, that is, 4-
β
-galactobiose and tri-galacto-oligosaccharides. The
cellular
immune activity of the purified GOS was evaluated b
y using Intestinal Epithelial Cells
(IECs). Results showed that GOS could significantly
(P< 0.05) promote IECs proliferation
in a dose and time dependent manner, and the relati
ve proliferation rate after 24 hours
culture was high up to 158%
at the concentration of 100
μ
g mL
-1
, which was three time
the value after 4 hours culture without GOS. Moreov
er, the production of IL-6 was
observably increased and up to 133.54 ng L
-1
with addition of 100
μ
g mL
-1
GOS. These
data implied that the purified GOS might have a rol
e in promoting the immune
adjustment, which could be utilized as a novel and
natural immunoregulatory agent in the
field of medicine and functional food. This work al
so revealed that the employment of
transgalactosylation activity of
β
-galactosidase derived from the fermentation of
probiotics such as
Lactobacillus delbrueckii subsp. bulgaricus
would enhance the value of
the milk product due to the form of GOS.
Keywords
: Fermentation, Galacto-oligasacchrides, Immunoregu
latory activity, Probiotics.
