Structural analysis of three novel trisaccharides isolated from the fermented beverage of plant extracts
Hideki Okada
2
Eri Fukushi
1
Akira Yamamori
2
Naoki Kawazoe
2
Shuichi Onodera
0
Jun Kawabata
1
Norio Shiomi
0
0
Department of Food and Nutrition Sciences, Graduate School of Dairy Science Research, Rakuno Gakuen University
, Ebetsu 069-8501,
Japan
1
Graduate School of Agriculture, Hokkaido University
, Sapporo 060-8589,
Japan
2
Ohtakakohso,
Co
, Ltd Otaru 047-0193,
Japan
Background: A fermented beverage of plant extracts was prepared from about fifty kinds of vegetables and fruits. Natural fermentation was carried out mainly by lactic acid bacteria (Leuconostoc spp.) and yeast (Zygosaccharomyces spp. and Pichia spp.). We have previously examined the preparation of novel four trisaccharides from the beverage: O--D-fructopyranosyl-(2->6)-O-D-glucopyranosyl-(1->3)-D-glucopyranose, O--D-fructopyranosyl-(2->6)-O-[-Dglucopyranosyl-(1->3)]-D-glucopyranose, O--D-glucopyranosyl-(1->1)-O--D-fructofuranosyl(2<->1)--D-glucopyranoside and O--D-galactopyranosyl-(1->1)-O--D-fructofuranosyl-(2<->1)-D-glucopyranoside. Results: Three further novel oligosaccharides have been found from this beverage and isolated from the beverage using carbon-Celite column chromatography and preparative high performance liquid chromatography. Structural confirmation of the saccharides was provided by methylation analysis, MALDI-TOF-MS and NMR measurements.
-
Background
A beverage was produced by fermentation of an extract
from 50 kinds of fruits and vegetables (see Additional file
1) [1,2]. The extract was obtained using sucrose-osmotic
pressure in a cedar barrel for seven days and was
fermented by lactic acid bacteria (Leuconostoc spp.) and yeast
(Zygosaccharomyces spp. and Pichia spp.) for 180 days. The
fermented beverage showed scavenging activity against
1,1'-diphenyl-2-picrylhydrazyl (DPPH) radicals, and
significantly reduced the ethanol-induced damage of gastric
mucosa in rats [1]. Analysis by high performance anion
exchange chromatography (HPAEC) showed that this
beverage contained high levels of saccharides, estimated
between 550 and 590 g/L; mainly glucose and fructose,
and a small amount of undetermined oligosaccharides.
Recently, it was reported that different positions of
glycosidic linkage of oligosaccharide isomers affected
physiological properties as well as physical properties [3-5].
Development of HPLC analysis with high sensitivity and
separation ability enables the detection and isolation of
oligosaccharides in the fermented beverage.
We have previously examined the preparation of
saccharides of the fructopyranoside series from the fermented
beverage of plant extracts, such as
O--D-fructopyranosyl(2->6)-D-glucopyranose [2],
O--D-fructopyranosyl-(2>6)-O--D-glucopyranosyl-(1->3)-D-glucopyranose and
O--D-fructopyranosyl-(2->6)-O-[-D-glucopyranosyl(1->3)]-D-glucopyranose [6]. The characteristics of
O-D-fructopyranosyl-(2->6)-D-glucopyranose were
non-cariogenicity and low digestibility, and the unfavorable
bacteria that produce mutagenic substances did not use the
saccharide [7,8]. Recently, we have studied isolation and
identification of novel non-reducing trisaccharides, such
as
O--D-glucopyranosyl-(1->1)-O--D-fructofuranosyl(2<->1)--D-glucopyranoside and
O--D-galactopyranosyl-(1->1)-O--D-fructofuranosyl-(2<->1)-
-D-glucopyranoside from the beverage [9], and those saccharides
were confirmed to be produced by fermentation.
In this paper, we have confirmed structures of the novel
trisaccharides (Fig. 1):
O--D-fructofuranosyl-(2->1)-O[-D-glucopyranosyl-(1->3)]--D-glucopyranoside
(named "3G--D-glucopyranosyl , -isosucrose"),
O-D-glucopyranosyl-(1->2)-O-[-D-glucopyranosyl-(1>4)]-D-glucopyranose (41--D-glucopyranosyl
sophorose) and
O--D-fructofuranosyl-(2->6)-O--D-glucopyranosyl-(1->3)-D-glucopyranose
(62--Dfructofuranosyl laminaribiose), isolated from the
fermented beverage using methylation analysis,
MALDITOF-MS and NMR measurements.
Results and discussion
Saccharides 1, 2 and 3 were isolated from the fermented
beverage of plant extracts using carbon-Celite column
chromatography, and were shown to be homogeneous
using anion exchange HPLC [tR, sucrose (relative retention
time; retention time of sucrose = 1.0): 1.89, 2.23 and 2.40
respectively]. The retention time of saccharides 1, 2 and 3
did not correspond to that of any authentic saccharides
[glucose (0.62), fructose (0.68), sucrose (1.00), maltose
(1.43), trehalose (0.58), laminaribiose (1.33), raffinose
(1.23), 1-kestose (1.47), 6-kestose (1.75), neokestose
(1.90), maltotriose (2.59), panose (1.87), nystose (2.06),
fructosylnystose (3.81),
O--D-fructopyranosyl-(2->6)-Dglucopyranose (0.83) [2],
O--D-fructopyranosyl-(2->6)O--D-glucopyranosyl-(1->3)-D-glucopyranose (1.74)
[6],
O--D-fructopyranosyl-(2->6)-O-[-D-glucopyranosyl-(1->3)]-D-glucopyranose (1.72) [6],
O--D-glucopyranosyl-(1->1)-O--D-fructofuranosyl-(2<->1)-
-Dglucopyranoside (1.24) [9],
O--D-galactopyranosyl-(1
HO HO
5 O
2
3 Glc OH 1
3 Glc O 1
OH
OH
gySFlrtiuragcunuocortpseuyrrl1e-a(sn1o->sfey23Ol)-(-](2-1 (...truncated)