Subscriber access provided by University of Sussex Library
Article
Crocus sativus petals: waste or valuable resource? The answer of HR- and HR-MAS NMR Valeria Righi, Francesca Parenti, Vitaliano Tugnoli, Luisa Schenetti, and Adele Mucci J. Agric. Food Chem., Just Accepted Manuscript • DOI: 10.1021/acs.jafc.5b03284 • Publication Date (Web): 14 Sep 2015 Downloaded from http://pubs.acs.org on September 15, 2015
Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
Journal of Agricultural and Food Chemistry is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.
Page 1 of 22
Journal of Agricultural and Food Chemistry
1
Crocus sativus petals: waste or valuable resource? The answer of HR- and HR-MAS NMR
2
Valeria Righi,† Francesca Parenti, ‡ Vitaliano Tugnoli,§ Luisa Schenetti,┴Adele Mucci*,‡
3 4 5 6 7 8 9 10 11
†
Dipartimento di Scienze per la Qualità della Vita, Università di Bologna, C.so D'Augusto 237,
47921 Rimini ‡
Dipartimento di Scienze Chimiche e Geologiche, Università di Modena e Reggio Emilia, Via G.
Campi 103, 41125 Modena §
Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, Via Belmeloro 8/A,
40123 Bologna ┴
Dipartimento di Scienze della Vita, Università di Modena e Reggio Emilia, Via G. Campi 103,
41125 Modena
12 13 14 15 16
Corresponding author:
17
Prof. A. Mucci
18
Dipartimento di Scienze Chimiche e Geologiche
19
Università di Modena e Reggio Emilia
20
Via G. Campi 103
21
41125 Modena
22
tel: 00390592058636
23
e-mail:
[email protected] 24
1 ACS Paragon Plus Environment
Journal of Agricultural and Food Chemistry
Page 2 of 22
25
ABSTRACT
26
Intact Crocus sativus petals were studied for the first time by HR-MAS NMR spectroscopy,
27
revealing the presence of kinsenoside (2) and goodyeroside A (3), together with 3-hydroxy-γ-
28
butyrolactone (4). These findings were confirmed by HR-NMR analysis of ethanol extract of fresh
29
petals
30
glucopyranosyloxybutanolides occurs during extraction. On the other hand, kaempferol 3-O-
31
sophoroside (1) which is “NMR-silent” in intact petals, is present in extracts.
32
These results suggest to evaluate the utilization of saffron petals for phytopharmaceutical and
33
nutraceutical purposes in order to exploit a waste product of massive production of commercial
34
saffron and point to the application of HR-MAS NMR for monitoring bioactive compounds directly
35
on intact petals avoiding extraction procedure and the consequent hydrolysis reaction.
and
showed
that,
even
though
carried
out
rapidly,
partial
hydrolysis
of
36 37
Keywords: Crocus sativus, Saffron, kinsenoside, goodyeroside A, kaempferol-3-O-sophoroside,
38
HR-MAS NMR
39 40
2 ACS Paragon Plus Environment
Page 3 of 22
Journal of Agricultural and Food Chemistry
41
INTRODUCTION
42
Crocus sativus (fam. Iridaceae) is cultivated in some part of Italy for the utilization of its stigmas
43
(saffron) in foods and sweets for both their intense colour and strong taste. Moreover, saffron has
44
also been used in preventive medicine: numerous pharmacological tests point to specific therapeutic
45
actions and many studies are focused on it.1
46
Crocus sativus petals represent the main by-product of saffron production. Considering that saffron
47
is one of the most commercialized spices, and that 1 kg of saffron is obtained from more than
48
160000 flowers, it is fair to ask whether it is possible to directly use the petals for
49
phytopharmaceutical or nutraceutical purposes or as raw material to obtain substances with
50
pharmacological activity.2 Very recently, a paper proposing the use of petals of Crocus sativus as
51
source of crocin and and kaempferol, appeared.3
52
A number of studies on hepatoprotective, anti-nociceptive, anti-inflammatory, anti-depressant
53
effects of saffron petal extracts are reported in the literature.3-5 It is also known that petals of Crocus
54
sativus contain kaempferol,6,7 which has been reported to be a tyrosinase inhibitor,7 and its
55
glycosides, especially kaempferol-3-O-sophoroside 1 (Fig. 1), which exhibit antioxidant and anti-
56
infammatory activity.8,9
57
Hence, the properties reported for petal extracts could be simply due to kaempferol derivatives, but
58
they could also be due to other bioactive species. Sprouts of Crocus sativus contain 3-(R)-3-β-D-
59
glucopyranosyloxybutanolide (kinsenoside 2, Fig. 1) and 3-(S)-3-β-D-glucopyranosyloxybutanolide
60
(goodyeroside A 3, Fig. 1),10 that derive from 3-hydroxy-γ-butyrolactone (4, Fig. 1) and have been
61
isolated also from other plants such as Anoectochilus and Goodyera species (Orchidaceae).11-14
62 63
Figure 1 near here
64 65
Both 2 and 3 exhibit hepatoprotective effects;14,15 2 is also antihyperglycemic,12 anti-
66
inflammatory,16 antihyperliposis,17 vascular protective,18 ovariectomy-induced bone loss preventive 3 ACS Paragon Plus Environment
Journal of Agricultural and Food Chemistry
Page 4 of 22
67
and osteoclastogenesis suppressing.19 For these reasons efforts towards efficient synthesis of 2 and
68
3 by a chemo-enzymatic approach have recently been reported.20
69
In order to gain a deeper insight into this subject, and to establish which are the main metabolites
70
present in Crocus sativus petals, we analysed them by high-resolution magic-angle-spinning NMR
71
(HR-MAS NMR) and their ethanol (95%) extract by high-resolution (HR-) NMR. HR-MAS NMR
72
spectroscopy allows to derive the biochemical profile of intact (human, animal or plant) tissues,21
73
formed by fast moving small metabolites, that give rise to narrow resonances. Through HR-MAS
74
NMR we tried to have a look inside a complex row matrix without disrupting its structure and
75
avoiding hydrolytic processes that can flank extraction. The purpose of this paper is to contribute to
76
the utilization of Crocus Sativus petals directly after the separation from saffron. To the best of our
77
knowledge, this is the first HR-MAS NMR study of petals.
78 79
EXPERIMENTAL SECTION
80 81
Plant Materials
82 83
Crocus sativus flowers were collected in Abruzzo (Italy), in the Aquila Saffron Protected
84
Designation of Origin (PDO) status, at the Farm "Vigna di More" located in Tione degli Abruzzi, in
85
autumn 2011. The flowers grew at 700 m above sea level. The bulbs were planted in August on a
86
ground prepared a year before (the soil is employed every five years) and the flowers were
87
harvested in October. The bulbs were put at 2-3 cm distance from each other, at least 8 cm depth
88
in rows of two or three, according to the space and land available. Flowers were hand-picked early
89
in the morning, before sunrise before perianth opening, and were placed in traditional wicker
90
baskets. After collection, they were stored at 5 °C and send to the lab, where intact petals were used
91
for HR-MAS NMR measurements within three days after collection. 4 ACS Paragon Plus Environment
Page 5 of 22
Journal of Agricultural and Food Chemistry
92 93
Extraction
94
Fresh petals (10 g) were extracted with 95% ethanol (Sigma Aldrich) and the extract vacuum
95
evaporated (150 mg). The whole process was carried out quickly at room temperature (about 1
96
hour). The extracts were analysed in high resolution NMR and in MS.
97 98 99
NMR measurements 1
H HR-MAS NMR spectra were recorded with a Bruker Avance400 (Bruker BioSpin) spectrometer
100
operating at a frequency of 400.13 MHz. The instrument was equipped with a 1H,13C HR-MAS
101
probe for semisolids and with a BBI probe for liquids. Before HR-MAS examination, intact saffron
102
petals were introduced in a MAS zirconia rotor (4 mm OD), 10 µL of D2O were added to provide
103
deuterium for the lock system, fitted with a 50 µl cylindrical insert to increase sample homogeneity,
104
and then transferred into the probe cooled to 5 ˚C. Experiments were performed at a temperature of
105
5˚C controlled by a Bruker cooling unit.
106
Samples were spun at 4000 Hz and one- (1D) and two-dimensional (2D) spectra were acquired by
107
using the sequences implemented in the Bruker software. The same experiments were carried out on
108
D2O extract solution at 25 °C, with a lower number of scans. To record 1H water-presaturated
109
spectrum, a composite pulse sequence (zgcppr) with 2 s water presaturation during the relaxation
110
delay, 8 kHz spectral width, 32k data points, 16-8 scans were used. 2D COSY (COrrelation
111
SpectroscopY) spectra were acquired using a standard pulse sequence (cosygpprqf) and 1 s water
112
presaturation during relaxation delay, 2-4 kHz spectral width, 2 k data points, 4 scans per
113
increment, 128 increments. 2D TOCSY (TOtal Correlation SpectroscopY) spectra were acquired
114
using a standard pulse sequence (mlevgpph19) and 1 s water presaturation during relaxation delay,
115
100 ms mixing (spin-lock) time, 2-4 kHz (spectral width, 4 k data points, 4 scans per increment,
116
512 increments. 2D HSQC (Heteronuclear Single Quantum Coherence) edited spectra were 5 ACS Paragon Plus Environment
Journal of Agricultural and Food Chemistry
Page 6 of 22
117
acquired using a standard pulse sequence echo-antiecho phase sensitive (hsqcedetgp) and 0.5 s
118
relaxation delay, 1.725 ms evolution time, 2-4 kHz spectral width in f2, 2 k data points, 16-8 scans
119
per increment, 15 kHz spectral width in f1, 256 increments. 2D HMBC (Heteronuclear Multiple
120
Quantum Coherence) spectra were acquired using a standard pulse sequence (hmbcgplpndqf) and
121
0.5 s relaxation delay, 50 ms evolution time, 2-4 kHz spectral width in f2, 2 k data points, 128-32
122
scans per increment, 22 kHz spectral width in f1, 256 increments.
123
Deconvolution of 1H NMR selected signals was run with MestReNova 9.1 (2014 Mestrelab
124
Research S.L.).
125 126
ESI ion-trap MS measurements
127
The negative ion ESI mass spectra and ESI-MS/MS data (collision energies: 10, 15, 20 or 35 eV)
128
were acquired with a LC-MS(n) Ion Trap 6310A (Agilent Technologies) coupled with a HPLC
129
Agilent Series 1200 equipped with a Zorbax SB-C18 column, 30x2.1mm ID, 3.5 µm particle size
130
(Agilent). Eluents: acetonitrile and H2O, 1% formic acid. Chromatographic runs were performed
131
using a gradient of 1% formic acid in acetonitrile (98 →10) in 1% formic acid in water (2 → 90).
132
The solvent flow rate was 0.2 ml/min, the temperature kept at 25°C and the injector volume
133
selected was 2 µl. Total ion current (TIC) chromatograms were acquired in both positive and
134
negative mode in the mass range between 100 and 1400 m/z. He was used as collision gas in MS2
135
experiments.
136 137
RESULTS & DISCUSSION
138
The water-presaturated 1H HR-MAS NMR spectrum of saffron petals, Fig. 2a, shows the
139
overlapped signals from a number of metabolites, mainly in the carbohydrate region, whereas only
140
broad and weak signals are found in the aromatic region, at about 6.9 and 7.7 ppm, where multiplets
141
from kaempferol derivatives are expected. These two broad resonances are sometimes assigned to 6 ACS Paragon Plus Environment
Page 7 of 22
Journal of Agricultural and Food Chemistry
142
polyphenols but they have also been attributed to NH protons.22 On the other hand, some multiplets
143
in the range 3.1-2.5 ppm, outside the common carbohydrate region, are detected and other low
144
signals mainly attributable to free aminoacids and lipids are present at lower ppm.
145
To disentangle the complex spectral pattern it was necessary to use 2D NMR homo- and hetero-
146
correlated experiments, such as COSY, TOCSY, HSQC and HMBC. We were thus able to
147
reconstruct molecular skeletons and to compare the chemical shifts and the correlation patterns to
148
those reported in the literature and in NMR databanks, such as HMDB (http://www.hmdb.ca/).
149
Using this approach, we found that the majority of signals in 1H spectrum are due to sucrose (Suc),
150
glucose (Glc) and fructose (Fru), as can be better seen observing HSQC correlations (Fig. 3). Apart
151
those of sugars, other resonances due to 2-4 are detected and assigned, through 2D experiments, as
152
reported in Table 1. The chemical shifts determined by us on intact petals parallel those reported in
153
pyridine-d5 by Zhang et al.20 Remarkably, even 2D NMR spectra did not highlight signals from
154
kaempferol or its derivatives in the aromatic region, meaning that, in the cell environment of fresh
155
petals, these molecules are not freely tumbling, but are probably associated with rigid structures
156
within the cell. Other minor resonances were confirmed to derive from free aminoacids (mainly
157
alanine, Ala, glutamine, Gln, and valine, Val).
158
The molar ratio of total 2-4 derivatives relative to water signal, estimated through deconvolution of
159
2-H signals of 2-4 at 2.8-2.5 ppm and of H2O at 4.97 ppm in the not-presaturated 1H NMR
160
spectrum, resulted around 0.3 mol %. It can be roughly converted to 0.8 % in weight with respect
161
water and then, considering a 75 % of water in petals, to 0.6 % of 2-4 in intact petals.
162 163
Figure 2 and 3 near here
164 165
Fresh petals were then extracted rapidly with 95 % ethanol, the vacuum evaporated residue was
166
solubilized in D2O and 1D, 2D NMR and ESI MS/MS spectra were acquired.
7 ACS Paragon Plus Environment
Journal of Agricultural and Food Chemistry
167
1
Page 8 of 22
H NMR spectrum of extract is reported in Fig. 2b, and it clearly displays signals in the aromatic
168
region that compare well with those reported by Wolfram et al.23 and were assigned, together with
169
other resonances in the carbohydrate region, to kaempferol 3-O-sophoroside 1 (Table 1), and to a
170
minor derivative that differs mainly for the 2',6'-H signals that are found at 8.09 ppm, 8-H at 6.78
171
(d, 2.2 Hz) and 6-H at 6.50 (d, 2.2 Hz) ppm and 1-HGlc 5.48 ppm (d, 7.6 Hz) and could be a 7-
172
substituted derivative of 1.
173
Apart from differences in the chemical shifts, due to a change from the cell environment to D2O
174
solution, resonances from 2-4 were detected also in the ethanol extract, even though in a ratio
175
different with respect to that observed in intact petals: the (2+3)/4 molar ratio passes from 2.5:1 in
176
intact petals to less that 1:1 in the extracts and at the same time the free glucose signals enhance
177
with respect to those of sucrose (1-HαGlc/1-Hsuc passes from 0.4 to 1.2). Hence, the extraction
178
process, even though carried out rapidly and without acidic conditions, promoted hydrolysis of 2
179
and 3 to 4 and free Glc.
180
ElectroSpray Ionization Ion Trap Mass Spectrometry (ESI-IT MS) was finally employed to confirm
181
the presence of 1 and to clarify the structure of the minor flavonol detected in ethanol extract (Fig.
182
4). The two major peaks detected in negative mode correspond to 609 and 771 m/z [M-H]- pseudo-
183
molecular ions. The collision induced fragmentation (CID) with He gas of 609 (highest) peak gave
184
429 m/z [M-C6H12O6-H]-and 285 m/z [kaempferol-H]- as expected for two subsequent hexose losses
185
starting from 1. On the other hand, CID of 771 m/z gave 609 m/z, corresponding to a loss of
186
C6H10O5 demonstrating that this derivative contains a further hexose unit. Minor peaks,
187
corresponding to pseudomolecular species of 625 m/z (which decomposes to 463 m/z through
188
hexose loss) and 651 m/z (which gives 471 m/z and 285 m/z under CID) were also detected. The
189
former could be due to quercetin sophoroside, the latter is probably an acetylated derivative.
190 191
Figure 4 near here 8 ACS Paragon Plus Environment
Page 9 of 22
Journal of Agricultural and Food Chemistry
192 193
In conclusion, this work shows that HR-MAS NMR can be employed to monitor bioactive
194
compounds freely tumbling in the cell environment, directly on intact petals. HR-MAS NMR
195
allows detecting the presence of 2, 3 and 4 directly on intact Crocus sativus petals, without the need
196
of extraction processes. Their content was estimated by HR-MAS NMR to be roughly 0.6 %. HR-
197
MAS NMR does not detect instead flavonols, especially 1, that are still contained in petals in a not
198
negligible amount, as demonstrated by 1H NMR analysis of ethanol extract. This implies that
199
flavonol derivatives in saffron petals have low tumbling rates, that could be due to their close
200
association to macromolecular species in cell walls.24
201
The 3-hydroxybutyrolactone derivatives 2-4 contained in Crocus sativus petals are biologically
202
active species that, together with 1, probably contribute to confer hepatoprotective,
203
antihyperglycemic, anti-inflammatory and other effects to petal extracts. The extraction process
204
leads to partial hydrolysis of petal constituents, hence it could be useful to evaluate the direct
205
employment of saffron petals for phytopharmaceutical and nutraceutical purposes, in order to better
206
exploit a waste product of massive production of commercial saffron.
207
The data presented in this study strongly support the idea that petals of Crocus sativus, are not a
208
waste, but they can be used for their biological activity in specific foods, as well as in herbalist
209
products. This can have a major impact for the community of saffron, the cultivation of which
210
represents an opportunity to improve and develop the economy of the agricultural sector in poor
211
European regions. The exploitation not only of stigmas but also of petals as raw material for health
212
enhancing products would further enhance the economical value of this activity and reduce waste
213
production.
214 215 216 9 ACS Paragon Plus Environment
Journal of Agricultural and Food Chemistry
Page 10 of 22
217
Acknowledgments
218
We are very grateful to Prof. Dario Iarossi and to "Vigna di More" farm, located in Tione degli
219
Abruzzi, for the supply of Crocus Sativus petals. http://www.valleaterno.it/vignadimore/
10 ACS Paragon Plus Environment
Page 11 of 22
Journal of Agricultural and Food Chemistry
220
Figure Legends
221
Fig. 1. Structures of identified compounds in Crocus sativus petals and ethanol extract.
222
Fig. 2. Water-presaturated 1H HR-MAS NMR spectrum of fresh saffron petals (a) and 1H NMR
223
spectrum of ethanol (95%) extract of fresh saffron petals in D2O solution (b).
224
Fig. 3. Enlarged carbohydrate (a) and aliphatic (b) regions of HSQC HR-MAS NMR spectrum of
225
fresh saffron petals. ChoCC =choline containing compounds.
226
Fig. 4. ESI-IT MS/MS spectra of 1 (left) and of minor kaempferol derivative (right).
227
11 ACS Paragon Plus Environment
Journal of Agricultural and Food Chemistry
Page 12 of 22
228
References
229
(1) Winterhalter, P.; Straubinger, M. Saffron: Renewed interest in an ancient spice. Food Rev Int.
230
2000, 16, 39–59.
231
(2) Montoro, P.; Tuberoso, C.I.G.; Maldini, M.; Cabras, P.; Pizza, C. Qualitative Profile and
232
Quantitative Determination of Flavonoids from Crocus sativus L. Petals by LC-MS/MS. Nat. Prod.
233
Commun. 2008, 3, 2013-2016.
234
(3) Zeka, K.; Ruparelia, K.C.; Continenza, M.A.; Stagos, D.; Vegliò, F.; Arroo, R.R.J. Petals of
235
Crocus sativus L. as a potential source of the antioxidants crocin and kaempferol. Fitoterapia 2015.
236
doi 10.1016/j.fitote.2015.05.014.
237
(4) Omidi, A.; Riahinia, N.; Montazer Torbati, M.B.; Behdani, M.A. Hepatoprotective effect of
238
Crocus sativus (saffron) petals extract against acetaminophen toxicity in male Wistar rats. J
239
Phytomed. 2014, 4, 330-336.
240
(5) Vijaya Bhargava, K. Medicinal Uses and Pharmacological Properties of Crocus sativus Linn.
241
(Saffron). Int J. Pharm. Pharm. Sci. 2011, 3, 22-26.
242
(6) Hadizadeh, F.; Khalilia, N.; Hosseinzadeh, H.; Khair-Aldine, R. Kaempferol from Saffron
243
Petals. Iranian J. Pharm. Res. 2003, 251-252.
244
(7) Kubo, I.; Kinst-Hori, I. Flavonols from Saffron Flower: Tyrosinase Inhibitory Activity and
245
Inhibition Mechanism. J. Agric. Food Chem. 1999, 47, 4121-4125.
246
(8) Yoon, H.-R.; Han, H.-G.; Paik, Y.-S. Flavonoid glycosides with antioxidant activity from the
247
petals of Carthamus tinctorius. J. Appl. Biol. Chem. 2007, 50, 175-178.
248
(9) Kim, T. H.; Ku, S.-K.; Lee, I.-C.; Bae, J.-S. Anti-inflammatory effects of kaempferol-3-O-
249
sophoroside in human endothelial cells. Inflammation Res. 2012, 61, 217-224.
250
(10) Gao, W.Y.; Li, Y.M.; Zhu, D.Y. Phenolic glucosides and a γ-lactone glucoside from the
251
sprouts of Crocus sativus. Planta Med. 1999, 65, 425-427.
12 ACS Paragon Plus Environment
Page 13 of 22
Journal of Agricultural and Food Chemistry
252
(11) Ito, A.; Kasa, R. Aliphatic and aromatic glucosides from Anoectochilus koshunensis.
253
Phytochemistry 1993, 33, 1133-1137.
254
(12) Du, X.M.; Yoshizawa, T.; Shoyama, Y. Butanoic acid glucoside composition of whole body
255
and in vitro plantlets of Anoectochilus formosanus. Phytochemistry 1998, 49, 1925-1928.
256
(13) Zhang, Y.H.; Cai, J.Y.; Ruan, H.L. Antihyperglycemic activity of kinsenoside, a high yielding
257
constituent from Anoectochilus roxburghii in streptozotocin diabetic rats. J. Ethnopharmacol. 2007,
258
114, 141−145.
259
(14) Du, X.M.; Sun, N.Y.; Chen, Y. Hepatoprotective aliphatic glycosides from three Goodyera
260
species. Biol. Pharm. Bull. 2000, 23, 731-734.
261
(15) Wu, J.B.; Lin, W.L.; Hsieh, C.C. The hepatoprotective activity of kinsenoside from
262
Anoectochilus formosanus. Phytother. Res. 2007, 21, 58-61.
263
(16) Hsiao, H.B.; Wu, J.B.; Lin, H.; Lin, W.C. Kinsenoside isolation from Anoectochilus
264
formosanus suppresses LPS-stimulated inflammatory reactions inmacrophages and endotoxin shock
265
in mice. Shock 2011, 35, 184-190.
266
(17) Du, X.M.; Sun, N.; Tamura, T. Higher yielding isolation of kinsenoside in Anoectochilus and
267
its antihyperliposis effect. Biol. Pharm. Bull. 2001, 24, 65-69.
268
(18) Liu, Z.L.; Liu, Q.; Xiao, B.; Zhou, J. The vascular protective properties of kinsenoside isolated
269
from Anoectochilus roxburghii under high glucose condition. Fitoterapia 2013, 86, 163-170.
270
(19) Hsiao, H.B.; Lin, H.; Wu, J.B.; Lin, W.C. Kinsenoside prevents ovariectomy-induced bone
271
loss and suppresses osteoclastogenesis by regulating classical NF-κB pathways. Osteoporos. Int.
272
2013, 24, 1663-1676.
273
(20) Zhang, Y.; Xia, Y.; Lai, Y.; Tang, F.; Luo, Z.; Xue, Y.; Yao, G.; Zhang Y.; Zhang, J.
274
Antihyperglycemic activity of kinsenoside, a high yielding constituent from Anoectochilus
275
roxburghii in streptozotocin diabetic rats. Molecules 2014, 19, 16950-16958.
13 ACS Paragon Plus Environment
Journal of Agricultural and Food Chemistry
Page 14 of 22
276
(21) Righi, V.; Schenetti, L.; Mucci, A. A new NMR technique: HR-MAS applied to animal and
277
vegetable soft materials. In New Trends in Analytical, Environmental and Cultural Heritage
278
Chemistry; Colombini, M.P., Tassi, L. Eds.; Transworld Research Network: Trivandrum, India,
279
2008; 31-42.
280
(22) Marino, G.; Righi, V.; Simoni, A.; Schenetti; L.; Mucci; A., Tugnoli; V., Muzzi, E.; Francioso,
281
O. Effect of a Peat Humic Acid on Morphogenesis in Leaf Explants of Pyrus communis and
282
Cydonia oblonga. Metabolomic Analysis at an Early Stage of Regeneration. J. Agric. Food Chem.
283
2013, 61, 4979-4987.
284
(23) Wolfram, K.; Schmidt, J.; Wray, V.; Milkowski, C.; Schliemann, W.; Strack, D. Profiling of
285
phenylpropanoids in transgenic low-sinapine oilseed rape (Brassica napus). Phytochemistry 2010,
286
71, 1076-1084.
287
(24) Hutzler, P.; Fischbach, R.; Heller, W.; Jungblut, T.P.; Reuber, S.; Schmitz, R.; Veit, M.;
288
Weissenböck, G.; Schnitzler, J.-P. Tissue localization of phenolic compounds in plants by confocal
289
laser scanning microscopy. J. Exp. Botany 1998, 49, 953-965.
290 291 292 293 294 295 296 297 298 299 300
14 ACS Paragon Plus Environment
Page 15 of 22
Journal of Agricultural and Food Chemistry
301 302 303 304 305 306 307 308
Table 1 1 H and 13C NMR data of 2-4 (ppma) in Crocus sativus petals as obtained by HR-MAS NMR and of 1-4 extracted with ethanol (95%) (D2O). 2b
2c
3b 1
C
1
179.7
-
C
1
1
-
182.5
-
180.3
-
-
2
2.99, 38.2 2.71 dd, 18.1, 6.1 Hz; d, 18.1 Hz)
2.87, 37.2 2.65 (dd, 18.0, 6.4 Hz; ddd, 18.0, 1.9, 0.8 Hz)
3.03, 38.5 2.78 dd, 18.6, 6.1 Hz; d, 18.6 Hz)
2.89, 38.1 2.73 (dd, 18.2, 1.4 Hz; dd, 18.2, 6.4 Hz)
2.97, 40.1 2.51 (dd, 18.1, 6.1 Hz; d, 18.1 Hz)
2.83, 39.7 2.37 (dd, 17.7, 5.8 Hz; dt, 17.7, 1.3 Hz)
-
160.3
3
4.86
77.9
4.72
77.2
4.86
77.9
4.73
77.4
4.71 70.0 (t, 4.6 Hz)
4.57 69.5 (ddt, 4.3, 5.8, 1.3 Hz)
-
136.1
4
4.55
77.4
4.54,d 4.49
77.3
4.59
77.9
4.47d
76.4
4.54, 79.8 4.36 (d, 10.3 Hz)
4.42, 78.9 4.22d (dd, 10.0, 4.3 Hz; dt, 10.0, 1.2 Hz)
-
nd
4a
-
106.9
5
-
164.2
6
6.22
101.0
7
-
167.2
8
6.42
95.9
8a
-
159.6
e
C
1
182.5
-
13
H
C
1
13
C
1
180.1
-
183.0
-
1c 13
H
13
4c
13
H
C
4b
1
H
13
3c
H
e
H
H
13
C
1'
4.55
103.9
4.40 104.8 (d, 7.8 Hz)
4.58
103.7
4.38 105.1 (d, 7.8 Hz)
-
123.9
2'
3.27
75.6
3.19
3.27
75.6
3.19
8.05
133.5
75.9
75.9
3'
3.49
78.4
3.36
79.2
3.49
78.4
3.36
79.2
6.92
117.5
4'
f
f
3.29
72.8
f
f
3.29
72.8
-
162.8
5'
f
f
79.2
f
f
3.29
79.2
6.92
117.5
6'
f
f
63.9
f
f
3.67, 3.88
63.9
8.05
133.5
5.43g
102.2
3.29 3.67, 3.88
1”
15 ACS Paragon Plus Environment
Journal of Agricultural and Food Chemistry
309 310 311 312 313 314 315 316 317 318 319 320
Page 16 of 22
2”
3.74h
84.3
3”
3.61
79.0
4”
3.36
5”
3.20
79.5
6”
3.49, 3.69
63.7
1”'
4.78
106.0
2”'
3.37
76.8
3”',4”',5”'
3.413.30
6”'
3.69, 3.80
63.5
a
chemical shifts refer to sucrose 1-H at 5.40 and 94.8 ppm, respectively; intact petals; c petals extracted with ethanol (95%); d long range correlation with C=O. e long range correlations at 4.40/77.2 ppm and 4.38/77.4 in HMBC spectrum. f overlapped to β-Glc. g long range correlations with 136.0 ppm carbon in HMBC spectrum h long range correlations with 102.2 and 106.0 ppm carbons in HMBC spectrum. b
321 322 323 324 325 326 327 328 329 330 331 332 333 16 ACS Paragon Plus Environment
Page 17 of 22
Journal of Agricultural and Food Chemistry
334 335 336 337 338
339 340 341
Fig. 1. Structures of identified compounds in Crocus sativus petals and ethanol extract.
342 343 344 345 346 347 348 349
17 ACS Paragon Plus Environment
Journal of Agricultural and Food Chemistry
Page 18 of 22
350 351 352 353
354 355
Fig. 2. Water-presaturated 1H HR-MAS NMR spectrum of fresh saffron petals (a) and 1H NMR
356
spectrum of ethanol (95%) extract of fresh saffron petals in D2O solution (b).
357 358 359 360 361 362
18 ACS Paragon Plus Environment
Page 19 of 22
Journal of Agricultural and Food Chemistry
363
364 365 366
Fig. 3. Enlarged carbohydrate (a) and aliphatic (b) regions of HSQC HR-MAS NMR spectrum of
367
fresh saffron petals. ChoCC =choline containing compounds.
368 369 19 ACS Paragon Plus Environment
Journal of Agricultural and Food Chemistry
Page 20 of 22
370 371 372
Fig. 4. ESI-IT MS/MS spectra of 1 (left) and of minor kaempferol derivative (right).
373 374
20 ACS Paragon Plus Environment
Page 21 of 22
375
Journal of Agricultural and Food Chemistry
TOC image
376
21 ACS Paragon Plus Environment
Journal of Agricultural and Food Chemistry
Page 22 of 22
kinsenoside
goodyeroside A
ACS Paragon Plus Environment