A new cyclolignan glycoside from the tubers of Pinellia ternata

Article abstract of DOI:10.1080/10286020.2015.1041931

A new 2,7′-type cyclolignan glycoside, cyclolignanyingoside A (1), together with six known compounds (2-7) were isolated from the tubers of Pinellia ternata (Thunb.) Breit. The structure of 1 was elucidated on the basis of chemical and spectral analysis, including 1D, 2D NMR analyses, HR-ESI-MS, and CD spectrometry. The cytotoxic, antioxidant and tyrosinase-inhibiting activities of all the isolates were determined. However, all the isolates exhibited no activity on the selected cell lines (Hep-3B, Bcap-37, and MCF-7). In addition, compounds 1-3 and 7 exhibited strong 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) free radical scavenging activity, and compounds 2 and 4 showed a moderate mushroom tyrsinase inhibitory activity.

Full text of DOI:10.1080/10286020.2015.1041931

This article was downloaded by: [New York University]
On: 26 May 2015, At: 02:14
Publisher: Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered
office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK
Journal of Asian Natural Products
Research
Publication details, including instructions for authors and
subscription information:
http://www.tandfonline.com/loi/ganp20
A new cyclolignan glycoside from the
tubers of Pinellia ternata
ab
ab
ab
ab
Ying-Ying Wu , Xiao-Xiao Huang , Jie Wu , Le Zhou , Dan-Qi
ab
ab
ab
ab
ab
Li , Qing-Bo Liu , Ling-Zhi Li , Xin-Jia Yan & Shao-Jiang Song
a
School of Traditional Chinese Materia Medica, Shenyang
Pharmaceutical University, Shenyang 110016, China
b
Key Laboratory of Structure-Based Drug Design & Discovery
(Ministry of Education), Shenyang Pharmaceutical University,
Shenyang 110016, China
Published online: 19 May 2015.
Click for updates
To cite this article: Ying-Ying Wu, Xiao-Xiao Huang, Jie Wu, Le Zhou, Dan-Qi Li, Qing-Bo Liu, Ling-
Zhi Li, Xin-Jia Yan & Shao-Jiang Song (2015): A new cyclolignan glycoside from the tubers of Pinellia
ternata, Journal of Asian Natural Products Research, DOI: 10.1080/10286020.2015.1041931
To link to this article: http://dx.doi.org/10.1080/10286020.2015.1041931
PLEASE SCROLL DOWN FOR ARTICLE
Taylor & Francis makes every effort to ensure the accuracy of all the information (the
“
Content”) contained in the publications on our platform. However, Taylor & Francis,
our agents, and our licensors make no representations or warranties whatsoever as to
the accuracy, completeness, or suitability for any purpose of the Content. Any opinions
and views expressed in this publication are the opinions and views of the authors,
and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content
should not be relied upon and should be independently verified with primary sources
of information. Taylor and Francis shall not be liable for any losses, actions, claims,
proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or
howsoever caused arising directly or indirectly in connection with, in relation to or arising
out of the use of the Content.
This article may be used for research, teaching, and private study purposes. Any
substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,
systematic supply, or distribution in any form to anyone is expressly forbidden. Terms &

Conditions of access and use can be found at http://www.tandfonline.com/page/terms-
and-conditions

Journal of Asian Natural Products Research, 2015
http://dx.doi.org/10.1080/10286020.2015.1041931
A new cyclolignan glycoside from the tubers of Pinellia ternata
ab
Ying-Ying Wu , Xiao-Xiao Huang , Jie Wu , Le Zhou , Dan-Qi Li , Qing-Bo Liu ,
ab
ab
ab
ab
ab
ab
ab
ab
Ling-Zhi Li , Xin-Jia Yan and Shao-Jiang Song *
a
School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang
1
Education), Shenyang Pharmaceutical University, Shenyang 110016, China
b
10016, China; Key Laboratory of Structure-Based Drug Design & Discovery (Ministry of
(
Received 26 January 2015; final version received 14 April 2015)
0
A new 2,7 -type cyclolignan glycoside, cyclolignanyingoside A (1), together with six
known compounds (2–7) were isolated from the tubers of Pinellia ternata (Thunb.)
Breit. The structure of 1 was elucidated on the basis of chemical and spectral analysis,
including 1D, 2D NMR analyses, HR-ESI-MS, and CD spectrometry. The cytotoxic,
antioxidant and tyrosinase-inhibiting activities of all the isolates were determined.
However, all the isolates exhibited no activity on the selected cell lines (Hep-3B, Bcap-
37, and MCF-7). In addition, compounds 1–3 and 7 exhibited strong 2,2 -azino-bis (3-
0
ethylbenzothiazoline-6-sulphonic acid) free radical scavenging activity, and
compounds 2 and 4 showed a moderate mushroom tyrsinase inhibitory activity.
Keywords: Araceae; Pinellia ternata; cyclolignan glycoside; cytotoxic activity;
antioxidant activity; tyrosinase-inhibiting activity
1
.
Introduction
China). In addition, there have been a lot
of counterfeit drugs used instead of
P. ternata. The chemical constituents
study can provide a basis for the quality
control of P. ternata. In this paper, we
describe the isolation and structural
elucidation of a new cyclolignan glyco-
side, along with six known compounds
obtained from the 75% EtOH extract of
P. ternata. Their structures (Figure 1) were
established by extensive spectroscopic
data analysis and comparison with litera-
ture values. Furthermore, the cytotoxic,
antioxidant and tyrosinase-inhibiting
activities of all the isolated compounds
were evaluated.
Pinellia ternata (Thunb.) Breit, a member
of the family Araceae, is widely distrib-
uted in China including Hubei, Anhui, and
Sichuan Provinces. Its tubers are one of the
most important original plants in Tra-
ditional Chinese Medicine which have
been used for antitussive, antiemetic, anti-
inflammatory, analgesic, antiulcer, and
anticancer effects in oriental medicine
[1–3]. Previous phytochemical studies on
P. ternata showed that many kinds of
compounds have been isolated from this
plant, such as alkaloids, lectins, fatty acids,
cerebrosides, volatile oils, flavonoids,
sterols, and phenylpropanoids [4–8].
P. ternata is also widely used in many
traditional medicine preparations, such as
Xiao Chai Hu Decoction and Xiao Qing
Long Decoction [9,10]. Our research is a
part of the chemical constituents basic
study for Xiao Chai Hu Decoction (the
National Natural Sciences Foundation of
2
.
Results and discussion
Compound 1 was obtained as a yellowish
gum, and the HR-ESI-MS exhibited a
molecular ion peak at m/z 677.2414
þ
[M þ Na] , corresponding to the molecular
*Corresponding author. Email: songsj99@163.com
q 2015 Taylor & Francis

2
Y.-Y. Wu et al.
Figure 1. The structures of compounds 1–7.
formula C H O . Compound 1 afforded
isolariciresinol, glucose, and apiose by an
acid hydrolysis experiment [11,12] that was
identified by comparison of its NMR
exhibited one methylene (dC 32.5), two
oxygenated methylenes (d 67.4 and 67.6),
three methines (d 37.4, 44.1 and 45.5), two
C
31 42 15
C
anomeric carbons (dC 109.3 and 103.9),
twelve aromatic carbons (d 111.9, 113.9,
spectral data with those in the literature
1
13]. In the H NMR spectrum, one 1,3,4-
C
[
trisubstituted aromatic ring [d 6.79 (1H, d,
115.5, 116.3, 121.1, 127.7, 132.7, 136.9,
144.0, 144.5, 145.5, and 147.2), two
methoxy groups (dC 55.5 and 55.6), and
one glucopyranoyl unit (dC 103.9, 73.5,
H
J ¼ 1.9 Hz), 6.48 (1H, dd, J ¼ 8.0, 1.9 Hz)
and 6.68 (1H, d, J ¼ 8.0 Hz)], a tetrasub-
1
13
stituted aromatic ring [d 6.59 (1H, s) and
H
76.6, 70.2, 75.8, and 62.7). The H and C
dH 6.07 (1H, s)], two anomeric protons [dH
NMR spectra of 1 were in part very similar
to those of isolariciresinol 9-O-b-D-gluco-
pyranoside [7] except for the presence of an
4
.85 (1H, d, J ¼ 2.9 Hz) and 3.94 (1H, d,
J ¼ 7.7Hz)], and two methoxyl groups [d
H
3.70 (3H, s) and dH 3.72 (3H, s)] were
observed (Table 1). The C NMR spectrum
apiofuranosyl unit (dC 109.3, 75.5, 78.8,
13
13
73.8, 63.2) [13]. Comparison of the
C
1
13
Table 1. H NMR (600 MHz) and C NMR (150 MHz) spectral data of compound 1 in DMSO-d6.
No.
d H
dC
No.
d H
dC
0
1
2
3
136.9
113.9
147.2
7
2.72 (2H, overlapped)
1.89 (1H, overlapped)
3.38–3.40 (1H, m)
3.80 (1H, overlapped)
3.94 (1H, d, J ¼ 7.7 Hz)
2.99 (1H, overlapped)
3.12–3.14 (1H, m)
3.17–3.19 (1H, m)
3.68 (1H, overlapped)
3.59 (1H, overlapped)
32.5
37.4
67.6
0
9 a
6.79 (1H, d, J ¼ 1.9 Hz)
8
0
0
9
b
00
4
5
6
7
8
144.5
115.5
121.1
45.5
44.1
67.4
Glu-1
103.9
73.5
76.6
70.2
75.8
62.7
0
0
0
0
0
0
0
0
0
0
6.68 (1H, d, J ¼ 8.0 Hz)
6.48 (1H, dd, J ¼ 8.0, 1.9 Hz)
4.03 (1H, d, J ¼ 10.6 Hz)
1.69 (1H, overlapped)
2
3
4
5
6
9
a
2.99 (1H, overlapped)
3
.47–3.49 (1H, m)
000
9
1
2
3
b
3.88–3.90 (1H, m)
6.59 (1H, s)
Api-1
000
4.85 (1H, d, J ¼ 2.9 Hz)
109.3
75.5
78.8
73.8
0
127.7
111.9
145.5
2
3.17 (1H, overlapped)
0
0
000
3
000
4
3.81 (1H, overlapped)
3
.67 (1H, overlapped)
3.28–3.30 (2H, m)
3.72 (3H, s)
0
0
0
000
3-OCH
4
5
6
144.0
116.3
132.7
5
63.2
55.5
55.6
6.07 (1H, s)
3
0
3 -OCH
3.70 (3H, s)
3
Note: Coupling constants (J) in Hz are given in parentheses; Chemical shift values are expressed in ppm.

Journal of Asian Natural Products Research
3
NMR spectral data (DMSO-d ) of 1 with
6
compound 1 had a trans–trans configur-
0
0
those of isolariciresinol 9-O-b-D-glucopyr-
anoside [7] revealed a downfield shift of C-
ation at C-7, C-8, C-8 . The (7S, 8R, 8 R)-
stereochemistry was elucidated by com-
parison of its circular dichroism (CD) and
optical rotation with the reported com-
pound urinatetralin [16] (see Experimen-
tal). Based on the above evidence, the
structure of 1 was unambiguously estab-
lished as shown in Figure 2 and it was
given the trivial name cyclolignanyingo-
side A.
0
9
sugar was located at C-9 . The b-anomeric
(4.9 ppm), indicating that an additional
0
configuration for the apiofuranosyl group
was determined from its C-1 data (109.3)
14]. The configuration of the anomeric
000
[
proton of glucose was proposed as b on the
basis of its coupling constants (J ¼ 7.7 Hz).
The absolute configurations of the mono-
saccharide units mentioned above were
successively determined as D and D, with
the help of GC analysis of their respective
derivatives [12]. The arrangements of the
hydroxyl, methoxyl, apiose, and glucose
moieties were determined by analysis of
the proton coupling patterns, HMQC, and
HMBC data (Figure 2). In the HMBC
spectrum, the correlation of the anomeric
proton at d 4.85 (1H, d, J ¼ 2.9 Hz,
The known compounds were readily
identified as isolariciresinol (2) [7],
isolariciresinol-9-O-b-D-glucopyranoside
(3) [7], medioresinol (4) [17], pinoresinol-
0
4 -O-b-D-glucopyranoside (5) [18], dehy-
drodiconiferyl alcohol-9-O-b-D-glucopyr-
anoside (6) [19] and dehydrodiconiferyl
0
alcohol-9 -O-b-D-glucopyranoside (7)
[19] by comparing NMR spectral data
with those reported in the literature.
0
00
0
apiofuranosyl H-1 ) with C-9 at d 67.6
All the isolated compounds were
evaluated for their cytotoxic activities
against breast cancer (Bcap-37), hepatoma
(Hep-3B) and breast cancer (MCF-7) cell
lines by the MTT Method [20], using 5-
fluorouracil as a positive control. How-
ever, none of the isolated compounds
exhibited any cytotoxicity. It has been
reported that alkaloids and lectins may be
responsible for the anti-tumor activity of
P. ternata [8]. Thus, lignanoids may
contribute to other effects of P. ternata.
Lignanoids have been claimed to
possess antioxidant activity and could
serve as lead compounds for the develop-
ment of antioxidant agents [21]. The
antioxidant effects of the isolates were
evaluated using 1,1-diphenyl-2-picrylhy-
0
revealed that the apiose was linked to C-9 ;
the correlation of the anomeric proton at
d 3.94 (1H, d, J ¼ 7.7 Hz, glucopyranosyl
0
0
H-1 ) with C-9 at d 67.4 revealed that the
glucose was linked to C-9 (Figure 2).
The configurations at C-7 and C-8
were confirmed by the large coupling
constants of H-7 (J ¼ 10.6 Hz) [15,16],
and there was no NOESY correlation
between H-7 and H-8, reflecting the trans
configuration at C-7 and C-8. Furthermore,
there was a correlation between H-7 and
0
H-8 from the NOESY spectrum. Thus,
0
drazyl (DPPH) and 2,2 -azinobis (3-
ethylbenzthiazoline-6-sulfonic
acid)
ABTS) assays. It has been reported that
(
the DPPH radical scavenging assay is
usually used to evaluate the ability of new
compounds or extracts to capture free
radicals, whereas the ABTS cation is
another synthetic radical which is more
versatile than DPPH, and the ABTS cation
model can be used to assess the scavenging
Figure 2. Key HMBC correlations of
compound 1.

4
Y.-Y. Wu et al.
Table 2. Antioxidant activities of compounds
–7.
significant activity with IC50 , 9.9 mg/ml,
in comparison with the positive control
trolox (IC50 ¼ 5.3 mg/ml).
1
Antioxidant activities
It has been reported that antioxidants
can prevent or delay pigmentation by
several different mechanisms, such as
scavenging ROS, reducing o-quinones,
and other intermediates in melanin bio-
synthesis [21]. Thus, there is a link
between the antioxidant-scavenging of
ROS and tyrsinase inhibitory effects [21].
Tyrosinase inhibition by the isolates (1–7)
was examined using mushroom tyrosinase
as described previously with minor modi-
fications, and arbutin was used as a
positive control [22]. The inhibition data
of mushroom tyrosinase are summarized
in Figure 3. Coumpounds 1, 3, and 5–7
exhibited weak inhibitory activity against
mushroom tyrosinase with 31.5%, 30.6%,
36.5%, 33.2%, and 32.6% inhibition at
500 mg/ml, respectively. However, com-
pounds 2 and 4 exhibited moderate
inhibitory activity against mushroom
tyrosinase with 45.3% and 53.3% inhi-
bition, respectively, at the same
concentration.
Compound
DPPH
ABTS
b
b
b
b
b
b
b
b
b
1
2
3
4
5
6
7
.100
75.6 ^ 3.7
7.4 ^ 0.7
2.9 ^ 0.4
7.4 ^ 0.8
22.7 ^ 1.4
9.9 ^ 1.1
9.1 ^ 1.3
4.5 ^ 0.6
5.3 ^ 0.7
b
b
.100
.100
.100
b
b
b
b
78.9 ^ 3.8
88.7 ^ 3.5
9.5 ^ 0.8
a
b
Trolox
Note: The IC50 greater than 100 mg/ml was
considered to indicate no antioxidant activities.
a
Trolox was used as positive control in test of
antioxidant activities.
b
IC50 (mg/ml) represents means ^ SD of three
independent replicates.
activity of both polar and nonpolar
samples [21]. The results of the DPPH
and ABTS radical scavenging activities of
all the isolates are summarized in Table 2.
All isolates (IC50 . 75.6 mg/ml) were
found to be less active than the positive
control trolox (IC50 ¼ 9.5 mg/ml) in the
DPPH assay. However, in the ABTS assay,
most of the isolated lignanoids showed
Figure 3. Tyrosinase inhibition of compounds 1–7 (at 500 mg/ml). Arbutin was used as positive
control; each column represents the mean ^ SD of triplicate determinations.

Journal of Asian Natural Products Research
5
3
.
Experimental
3.3 Extraction and isolation
3
.1 General experimental procedures
The air-dried and powdered tubers of
P. ternata (15 kg) were extracted with
Optical rotations were measured on a
JASCOP-1020 Polarimeter (Jasco Co.,
Tokyo, Japan). UV spectra were carried
out on a Shimadzu UV-1700 Spectropho-
tometer (Shimadzu Corporation, Kyoto,
Japan). IR spectra were obtained on a
Shimadzu ftir-8400s spectrophotometer
7
5% EtOH for three times. The solvent
was evaporated under vacuum. The extract
400 g) was suspended in H O (5 L). Then,
(
2
the extract (400 g) was chromatographed
over D101 macroporous resin column using
H O–EtOH as eluent. The H O–EtOH (v/v
2
2
(
Shimadzu Corporation). NMR spectra
30:70) fraction (100 g) was subjected to
ODS CC and eluted with H O–CH OH
were recorded on Bruker ARX-400 and
ARX-600 instruments (Bruker Co.,
Billerica, MA, USA). HR-ESI-TOF-MS
experiments were performed on a Micro
TOF spectrometer (Bruker Co., Karlsruhe,
Germany). CD spectra were measured by
MOS 450 detector (Bio-Logic Co., Claix,
France). High-performance liquid chroma-
tography (HPLC) preparation was carried
out on an Agilent 1100 instrument
2
3
(from v/v 90:10 to 0:100) to give four
fractions (Fr. A–D). Fraction B (4 g) was
further separated over silica gel CC by
CH Cl –CH
2
OH (v/v 25:1–3:1) to yield
–B ). Subfraction B
3
2 3
six subfractions (B
1
6
(300 mg) was subjected to semipreparative
HPLC [Agilent 1100 instrument; YMC
5 mm C18 column (250 mm £ 10 mm)],
eluted with CH CN–H O (v/v 18:82,
3
2
(
Agilent, Santa Clara, CA, USA) equipped
3.5 ml/min) to yield compound 2 (41 mg,
t ¼ 52min). Subfraction B (202 mg) was
with prep-ODS (10 mm £ 250 mm). GC
was done on an Agilent 7890A Gas Chro-
matograph (Agilent) equipped with HP-5
capillary column (30 m £ 320 mm £
R
5
further purified by semipreparative HPLC
(CH CN–H O, v/v 20:80, 3.5 ml/min) to
3
2
produce compound 5 (4.7 mg, t ¼ 43 min).
R
0
.25 mm). Silica gel (200–300 mesh,
Similarly, subfraction B (670 mg) was
6
Qingdao Marine Chemistry Ltd, Qingdao,
China), macroporous resin (D101, Cangz-
hou Bon Adsorber Technology Co., Ltd,
Cangzhou, China), and Cosmosil octade-
cyl silane (ODS; 40–80 mm, Nacalai
Tosoh, Inc., Uetikon, Switzerland) were
used for column chromatography (CC).
TLC was conducted on silica gel GF254
subjected to semipreparative HPLC, eluted
with CH CN–H O (v/v 22:78, 3.5 ml/
3
2
min) to afford compounds 1 (13.6 mg,
t ¼ 30min) and 3 (27 mg, t ¼ 44 min).
R
R
Fr. C (6 g) was fractionated by silica gel CC
eluted with a step-wise gradientof CH Cl –
CH OH (v/v 30:1–6:1) to afford five
2
2
3
subfractions (C –C ). Subfraction C
1
1
5
(Qingdao Marine Chemistry Ltd).
(780 mg) was subjected to preparative
HPLC [Agilent 1100 instrument; Acchrom-
3
.2 Plant material
XAqua 5 mm C18 column (250 mm
£
20 mm)], eluted with CH OH–H O (v/v
3 2
The air-dried tubers (15 kg) of P. ternata
were collected in November 2013 from
The China National GAP Base of the
Chinese Materia for P. ternata in Guizhou,
China. The species was identified by
Professor Jin-Cai Lu, Department of
Pharmacognosy, Shenyang Pharmaceutical
University. A voucher specimen (No.
1
5:85, 7 ml/min), to produce four subfrac-
tions (C1 – 1 –C1 – 4). Subfraction C1 – 3
(139 mg) was further purified by semipre-
parative HPLC (CH
3.5 ml/min) to produce compound 4 (8 mg,
¼ 50min). Subfraction C4 (223 mg) was
purified in the same way using CH CN–
O (v/v 25:75, 3.5 ml/min) as the eluent to
CN–H O, v/v 25:75,
3
2
t
R
3
2
0131116) has been deposited in the
H
2
Herbarium of Shenyang Pharmaceutical
University, Liaoning, China.
afford compounds 6 (8 mg, t
and 7 (5 mg, t ¼ 47.1 min).
R
¼ 45 min)
R

6
Y.-Y. Wu et al.
3
.3.1 Cyclolignanyingoside A (1)
2
3.5. Antioxidant assays
5
Yellow oil, ½aꢀ 2 43.1 (c 0.1, MeOH).
In this assay, trolox (purity . 98%;
Sigma, Los Angeles, CA, USA) was used
as a positive control. A 0.1-mM solution of
DPPH radical in ethanol was prepared, and
100 ml of this solution was mixed with
100 ml of sample solution. The mixture
was incubated for 30 min in a darkroom at
room temperature. Scavenging capacity
was read spectrophotometrically by moni-
toring the decrease in absorbance at
D
2
(cm ): 3376, 1645, 1573,
1
IR (KBr) v
1
max
514, 1449, and 1417; UV (MeOH) l
max
1
D1): 210 (0.945) and 283 (0.166) nm. H
(
and C NMR spectral data (DMSO-d6),
see Table 1; HR-ESI-MS: m/z 677.2414
1
3
þ
[
M þ Na] (calcd for C H O Na,
3
1
42 15
0,
13.0nm
6
77.2416); CD (MeOH) D1
3
D1293.1nm 2 21.982, D1280.1nm þ 8.54 03 ,,
D1270.7nm þ 9.576,
D1
254.2nm
zþ
D1248.1nm þ 12.461, D1
D1213.3nm þ 16.139, D1
2 4.134,
2 5.832.
517 nm. ABTS radical cation (ABTS )
228.4nm
was produced by reacting 7 mM stock
solution of ABTS with 2.45 mM potassium
persulfate (final concentration) and allow-
ing the mixture to stand in the dark at room
temperature for 12–16 h before use. The
204.7nm
3
.4 Acid hydrolysis of compound 1
·
þ
Each compound (3.0 mg) was hydrolyzed
with 2 M HCl (5.0 ml), heated for 4 h at
ABTS solution was diluted with ethanol,
to an absorbance of 0.7 ^ 0.02 at 734 nm.
An ethanolic solution (50 ml) of the
samples at various concentrations was
9
58C and extracted with CHCl3 (3
5.0 ml). Then the aqueous layer was
concentrated in vacuo to appropriate
£
zþ
mixed with 150 ml diluted ABTS sol-
volume, and the solution was examined
by TLC (EtOAc–BuOH–H O–HOAc,
ution. After reaction at room temperature
for 20 min, the absorbance was measured
at 734 nm using a Varioskan Flash Multi-
mode Reader (Thermo Scientific, Wal-
tham, MA, USA).
2
4
:4:1:1) and comparison with the auth-
entic sample, and thus glucose and apiose
were detected. Each remaining aqueous
layer was concentrated to dryness to give
a residue, which was dissolved in
pyridine (1.0 ml), and then L-cysteine
methyl ester hydrochloride (2.0 mg) was
added to the solution. The mixture was
heated at 608C for 2 h, and 0.5 ml N-
The capability to scavenge the DPPH/
zþ
ABTS was calculated using the formula
zþ
given below: DPPH/ABTS scavenging
activity (%) ¼ [1–(S–S )/(C–C )] £ 100,
B
B
where S, S , C, and C are the absorbencies
B
B
of the sample, the blank sample, the
control, and the blank control, respect-
ively [23].
(trimethylsily)imidazole was added, fol-
lowed by heating at 608C for 2 h. The
reaction product was subjected to GC
analysis on Agilent 7890 A (HP-5, 30 m
£
320 mm, 0.25 mm) with flame ioniz-
ation detector. Column temperature was
3.6. Inhibitory activity to tyrosinase
This assay was performed according to the
procedure of Dai et al. [22] with slight
modifications, using L-tyrosine as a sub-
strate. Arbutin (purity . 98%; Sigma) was
used as a positive control.
set at 120–2808C with the rate of 88C/
min, and the carrier gas was N (1.4 ml/
2
min), injection temperature 2508C; injec-
tion volume 1 ml. The absolute configur-
ations of the monosaccharides were
confirmed to be D-apiose and D-glucose
by comparison of the retention times of
Acknowledgements
its Me Si ethers with those of standard
3
Authors thank Mrs Wen Li. and Mr Yi Sha of
Shenyang Pharmaceutical University for
recording of NMR spectra.
samples [tR (D-apiose) 12.80 min, tR (D-
glucose) 25.87 min].

Journal of Asian Natural Products Research
7
Disclosure statement
Nat. Prod. Res. 16, 376 (2014). doi:10.
080/10286020.2014.884082.
12] W.S. Feng, Y.Y. Pei, X.K. Zheng,
C.G. Li, Y.Y. Ke, Y.Y. Lv, and
Y.L. Zhang, J. Asian Nat. Prod. Res. 16,
393 (2014). doi:10.1080/10286020.2013.
1
No potential conflict of interest was reported by
the authors.
[
Funding
8
23951.
Financial supports from the National Natural
Sciences Foundation of China (Nos 81130071
and 81373925) and Program for Liaoning
Excellent Talents in University (LR2012034).
[
[
[
13] T. Kanchanapoom, P. Chumsri, R. Kasai,
H. Otsuka, and K. Yamasaki, Phytochem-
istry 63, 985 (2003). doi:10.1016/S0031-
9
422(03)00219-X.
14] I. Kitagawa, K. Hori, M. Sakagami,
F. Hashiuchi, M. Yoshikawa, and J. Ren,
Chem. Parm. Bull. 41, 1350 (1993).
doi:10.1248/cpb.41.1350.
15] P.L. Klause, K. Maki, S. Andreas, and
K. Herbert, Phytochemistry 69, 820
References
[
[
[
[
1] M.H. Han, X.W. Yang, M. Zhang, and
G.Y. Zhong, Chromatographia 64, 647
(
2006). doi:10.1365/s10337-006-0103-8.
2] T. Maki, K. Takahashi, and S. Shibata,
Planta. Med. 53, 410 (1987). doi:10.1055/
s-2006-962759.
3] S.Y. Liu, C.L. You, and Y.M. Wang,
Pharmacol. Clin. Chin. Mater. Med. 9, 27
(1993).
4] J.H. Chen, G.Y. Cui, J.Y. Liu, and
R.X. Tan, Phytochemistry 64, 903
(2008). doi:10.1016/j.phytochem.2007.
08.032.
[16] C.C. Chang, Y.C. Lien, C.S. Liu, C. Lee,
and S.S. Lee, Phytochemistry 63, 825
(2003). doi:10.1016/S0031-9422(03)
00371-6.
[17] Q. Sun, J. Wu, F. Li, T. Yu, L. Li, and
S. Song, J. Shenyang Pharm. Univ. 31, 94
(2014).
(
2003). doi:10.1016/S0031-9422(03)
0421-7.
5] F. Yamamoto, Chem. Abstr. 114, 886
1991).
6] H. Yang, G.X. Chou, and Z.T. Wang,
Chin. Pharm. J. 42, 99 (2007).
7] J.K. Xu, T.L. Zhang, G.Q. Yi, Y. Xu,
H.H. Wu, Y.H. Pei, and J. Shenyang,
Pharm. Univ. 27, 429 (2010).
0
[
[
[
[
18] D.M. Wang, W.J. Pu, Y.H. Wang,
Y.J. Zhang, and S.S. Wang, Molecules
(
17, 4595 (2012). doi:10.3390/mol-
ecules17044595.
[
[
19] Z.S. Akdemir and I.I. Tatli, Turk. J. Chem.
28, 621 (2004).
20] F.Z. Liu, J.W. Ren, J.S. Tang, X.Z. Liu,
Y.S. Che, and X.S. Yao, Fitoterapia 87,
[
8] X. Ji, B.K. Huang, G.W. Wang, and
C.Y. Zhang, Fitoterapia 93, 1 (2014).
doi:10.1016/j.fitote.2013.12.010.
7
0
8 (2013). doi:10.1016/j.fitote.2013.03.
22.
[
9] G.Y. Su, J.Y. Yang, F. Wang, J. Ma,
K. Zhang, Y.X. Dong, S.J. Song, X.M. Lu,
and C.F. Wu, J. Ethnopharmacol. 152,
[
21] X.X. Huang, Q.B. Liu, J. Wu, L.H. Yu,
Q. Cong, Y. Zhang, L.L. Lou, L.Z. Li, and
S.J. Song, Planta. Med. 80, 1732 (2014).
doi:10.1055/s-0034-1383253.
22] Y. Dai, G. Zhou, H. Kurihara, W. Ye, and
X. Yao, J. Nat. Prod. 69, 1022 (2006).
doi:10.1021/np0600853.
23] S.B. Wu, J. Wu, Z.W. Yin, J.Z. Zhang,
C.L. Long, E.J. Kennelly, and S.P. Zheng,
J. Agric. Food. Chem. 61, 4035 (2013).
doi:10.1021/jf400487g.
2
0
17 (2014). doi:10.1016/j.jep.2014.01.
06.
[
[
[
10] T. Nagai, Y. Arai, M. Emori,
S.Y. NuNome, T. Yabe, T. Takeda, and
H. Yamada, Int. Immunopharmacol. 4,
[
1
0
353 (2004). doi:10.1016/j.intimp.2004.
5.021.
11] X.J. Yan, X.Y. Bai, Q.B. Liu, S. Liu,
P.Y. Gao, L.Z. Li, and S.J. Song, J. Asian