Structural Identification and Conversion Analysis of Malonyl Isoflavonoid Glycosides in Astragali Radix by HPLC Coupled with ESI-Q TOF/MS
Abstract
:1. Introduction
2. Results and Discussion
2.1. Compound Separation and Structural Identification
2.2. LC-QTOF/MS Analysis of the Extract of Astragali Radix
2.2.1. Identification of Malonyl Isoflavone Glycosides and Related Aglycones
2.2.2. Analysis of Malonyl Isoflavan Glycosides and Related Aglycones
2.2.3. Characterization of Malonyl Pterocarpan Glycosides and Related Aglycones
2.3. Conversion Analysis of MIGs in Astragali Radix under Different Extract Conditions
2.3.1. Calibration Curves, Linearity, Limits of Detection, and Quantification
2.3.2. Content Variation of MIGs, Related Glycosides and Aglycones in Different Extraction Samples of Astragali Radix
3. Materials and Methods
3.1. Samples, Chemicals and Reagents
3.2. Isolation and Identification ofMIGs
3.3. Chromatographic Methods
3.4. LC-TOF/MS Conditions
3.5. Sample Solution Preparation
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Conflicts of Interest
References
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Sample Availability: Samples of the compounds calycosin-7-O-glycoside-6″-O-malonate and formononetin-7-O-glycoside-6″-O-malonate are available from the authors. |
Position | AR-1 | AR-2 | AR-3 | AR-4 | Position | AR-1 | AR-2 | AR-3 | AR-4 | ||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
δC | δH (J, Hz) | δC | δH (J, Hz) | δC | δH (J, Hz) | δC | δH (J, Hz) | δC | δH (J, Hz) | δC | δH (J, Hz) | δC | δH (J, Hz) | δC | δH (J, Hz) | ||
2(6) | 153.5 | 8.34(s) | 153.7 | 8.40(s) | 65.8 | 4.28(m); 3.65(m) | 69.6 | 4.19(m); 3.97(m) | 5′(10) | 119.7 | 6.97(brs) | 113.7 | 7.00(d,8.0) | 133.4 | - | 103.2 | 6.46(d,8.5) |
3(6a) | 123.6 | - | 123.4 | - | 39.5 | 3.65(m) | 31.3 | 3.36(m) | 6′(10a) | 116.4 | 7.07(brs) | 130.1 | 7.53(d,8.0) | 150.9 | - | 121.4 | 6.79(d,8.5) |
4(1b) | 174.7 | - | 174.7 | - | 78.2 | 5.60(d,6.0) | 29.7 | 2.92(m); 2.81(m) | 1″(1′) | 99.8 | 5.13(d,7.5) | 99.7 | 5.15(d,7.5) | 100.1 | 4.86(d,7.5) | 100.8 | 4.79(d,8.0) |
5(1) | 127.1 | 8.07(d,8.8) | 127.1 | 8.08(d,8.8) | 132.1 | 7.44(d,8.5) | 130.1 | 7.01(d,8.5) | 2″(2′) | 76.2 | 3.34(m) | 76.2 | 3.34 (m) | 76.3 | 3.27(m) | 76.3 | 3.28(m) |
6(2) | 115.4 | 7.15(dd,8.8,2.2) | 115.4 | 7.15(dd,8.8,2.2) | 110.2 | 6.72(dd,8.5,2.5) | 108.6 | 6.53(dd,8.5,2.5) | 3″(3′) | 73.0 | 3.33(m) | 73.0 | 3.32 (m) | 73.1 | 3.25(m) | 73.6 | 3.23(m) |
7(3) | 161.2 | - | 161.2 | - | 158.3 | - | 156.4 | - | 4″(4′) | 69.7 | 3.22(m) | 69.7 | 3.20 (m) | 69.8 | 3.16(m) | 70.3 | 3.17(m) |
8(4) | 103.6 | 7.21(d, 2.2) | 103.6 | 7.23(d,2.2) | 104.2 | 6.54(d,2.5) | 103.9 | 6.45(d,2.5) | 5″(5′) | 73.9 | 3.76(m) | 73.8 | 3.76(m) | 73.7 | 3.61(m) | 74.2 | 3.59(m) |
9(4a) | 156.9 | - | 157.0 | - | 156.1 | - | 154.7 | - | 6″(6′) | 64.1 | 4.41(m); 4.11(m) | 64.1 | 4.41(brs); 4.12(brs) | 64.1 | 4.37(m); 4.08(m) | 64.5 | 4.33(m); 4.10(m) |
10(1a) | 118.6 | - | 118.6 | - | 114.0 | - | 115.9 | - | 1‴(1″) | 166.9 | - | 166.9 | - | 166.8 | - | 166.2 | - |
1′(6a) | 124.5 | - | 124.0 | - | 121.6 | - | 120.8 | - | 2‴(2″) | 41.5 | 3.38(s) | 41.5 | 3.40(s) | 41.3 | 3.38(s) | 42.3 | 3.33(s) |
2′(7) | 112.0 | 6.97(brs) | 130.1 | 7.53(d,8.0) | 118.7 | 6.99(d,8.0) | 148.2 | - | 3‴(3″) | 167.9 | - | 168.0 | - | 167.9 | - | 169.0 | - |
3′(8) | 146.1 | - | 113.7 | 7.00(d,8.0) | 105.1 | 6.53(d,8.0) | 136.1 | - | 4′(9)-OCH3 | 55.7 | 3.80(s) | 55.2 | 3.79(s) | 56.0 | 3.74(s) | 56.1 | 3.75(s) |
4′(9) | 147.6 | - | 159.0 | - | 152.7 | - | 151.7 | - | 3′(8)-OCH3 | - | - | - | - | 59.9 | 3.72(s) | 60.9 | 3.50(s) |
Classification | Peak | tR (min) | Molecular Formula | [M + H]+/ [M + NH4]+ | [Aglycone + H]+ | MSn (Characteristic Fragment Ions) | Identification | Reference |
---|---|---|---|---|---|---|---|---|
Isoflavones | 1 * | 12.71 | C22H22O10 | 447.1273/- | 285.0749 [M + H-Glc]+ | 270.0506, 269.0432, 253.0484, 242.0570, 225.0534, 214.0618, 213.0537, 197.0591, 137.0234 | Calycosin-7-O-Glc | [12,21] |
2 | 13.20 | C23H24O11 | 477.1382/- | 315.0867 [M + H-Glc]+ | 300.0640, 299.0536, 283.0590, 272.0684, 255.0668, 244.0721, 243.0652, 227.0697, 167.0346 | Odoratin-7-O-Glc | [21,24] | |
4 | 17.45 | C26H26O14 | 563.1323/- | 315.0867 [M + H-Glc-Mal]+ | 300.0635, 299.0571, 283.0631, 272.0675, 255.0650, 244.0731, 243.0654, 227.0695, 167.0328 | Odoratin-7-O-Glc-6″-O-Mal | [21] | |
5 | 17.80 | C25H24O13 | 533.1276/- | 285.0750 [M + H-Glc]+ | 270.0523, 269.0451, 253.0500, 242.0570, 225.0546, 214.0624, 213.0548, 197.0597, 137.0243 | Isomer calycosin-7-O-Glc-6″-O-Mal | [21] | |
6 * | 18.31 | C25H24O13 | 533.1273/- | 285.0742 [M + H-Glc-Mal]+ | 270.0506, 269.0434, 253.0477, 242.0567, 225.0530, 214.0615, 213.0534, 197.0588, 137.0229 | Calycosin-7-O-Glc-6″-O-Mal | [12,21] | |
8 * | 22.77 | C22H22O9 | 431.1327/- | 269.0809 [M + H-Glc]+ | 254.0575, 253.0502, 237.0547, 226.0624, 213.0917, 197.0602 | Formononetin-7-O-Glc (Ononin) | [21,22] | |
9 | 23.05 | C23H24O10 | 461.1426/- | 299.0924 [M + H-Glc]+ | 284.0693, 283.0653, 267.0636, 256.0737, 243.1017, 239.0703, 228.0830, 227.0687, 167.0377 | 6,4′-dimethoxyisoflavone-7-O-Glc | [21] | |
13 | 27.84 | C26H26O13 | 547.1421/- | 299.0921 [M + H-Glc-Mal]+ | 284.0692, 283.0639, 267.0613, 256.0748, 243.1021, 239.0709, 228.0754, 227.0689, 167.0340 | Afrormosin -7-O-Glc-6″-O-Mal | [24] | |
14 * | 28.14 | C25H24O12 | 517.1321/- | 269.0794 [M + H-Glc-Mal]+ | 254.0564, 253.0486, 237.0538, 226.0620, 213.0904, 197.0595, 137.0232 | Formononetin-7-O-Glc-6″-O-Mal | [12,22] | |
15 * | 28.87 | C16H12O5 | 285.0749/- | - | 270.0517, 269.0446, 253.0495, 242.0580, 225.0547, 214.0623, 213.0542, 197.0600, 137.0240 | Calycosin | [12,22] | |
22 * | 39.50 | C16H12O4 | 269.0803/- | - | 254.0582, 253.0499, 237.0551, 226.0631, 213.0918, 197.0603, 137.0251 | Formononetin | [12] | |
23 | 40.12 | C17H14O5 | 299.091/- | - | 284.0689, 283.0606, 267.0660, 256.0740, 243.1025, 239.0709, 167.0368 | Afrormosin (7-hydroxy-6,4′-dimethoxyisoflavon) | [25] | |
26 | 43.20 | C17H16O4 | 285.1117/- | - | 270.0527, 269.0439, 242.0590, 214.0621, 213.0546, 153.0202 | Biochanin A(5,7-dihydroxy-4′-methoxyisoflavon) | [12] | |
Isoflavans | 3 | 15.98 | C29H38O15 | 627.2366/ 644.2530 | 303.1223 [M + H-2Glc]+ | 465.1755, 193.0871, 181.0860, 167.0701, 165.0550, 161.0605, 152.0466, 147.0443, 133.0659, 123.0455 | Isomucronulatol-7-O-Glc-Glc | - |
12 | 26.73 | C23H28O10 | 465.1739/ 482.2003 | 303.1217 [M + H-Glc]+ | 193.0861, 181.0861, 167.0695, 165.0553, 161.0599, 152.0471, 147.0441, 133.0655, 123.0442 | Astraisoflavanglycoside (2′-hydroxy-3′,4′-dimethoxy isoflavone-7-O-Glc) | [12] | |
18 * | 30.76 | C26H30O13 | 551.1738/ 568.2004 | 303.1230 [M + H-Glc-Mal]+ | 515.1529, 497.1435, 411.1429, 193.0858, 181.0858, 167.0692, 165.0545, 161.0600, 152.0473, 147.0545, 133.0655, 123.0441 | Astraisoflavanglycoside-6″-O-Mal | [12,22] | |
19 | 31.23 | C26H30O13 | 551.1740/ 568.2003 | 303.1231 [M + H-Glc-Mal]+ | 515.1573, 497.1466, 411.1453, 193.0862, 181.0861, 167.0705, 165.0548, 161.0599, 152.0467, 147.0441, 133.0651, 123.0452 | Isomer astraisoflavanglycoside-6″-O-Mal | - | |
21 | 34.24 | C25H30O11 | 507.1856/ 524.2102 | 303.1233 [M + H-Glc-Ac]+ | 471.1678, 453.1582, 411.1440, 193.0845, 181.0864, 167.0706, 165.0552, 161.0602, 152.0471, 147.0444, 133.0661, 123.0453 | Isomucronulatol-7-O-Glc-6″-O-Ac | [21] | |
25 | 41.46 | C17H18O5 | 303.1224/- | - | 193.0864, 181.0872, 167.0707, 161.0606, 152.0475, 147.0441, 133.0658, 123.0454 | Isomucronulatol | [21] | |
Pterocarpans | 7 | 18.90 | C22H24O10 | 449.1424/ 466.1697 | 287.0924 [M + H-Glc]+ | 259.0976, 255.0675, 227.0694, 177.0551, 153.0553, 147.0447, 138.0314, 123.0463 | licoagroside D (10-dihydroxy-9- methoxypterocarpan-3-O-Glc) | [26] |
10 | 23.64 | C25H26O13 | 535.1428/ 552.1690 | 287.0920 [M + H-Glc-Mal]+ | 499.1230, 481.1145, 395.1155, 259.0989, 255.0655, 227.0695, 177.0555, 153.0553, 147.0441, 138.0316, 123.0464 | 10-dihydroxy-9-methoxypterocarpan-3-O-Glc-6′-O-Mal | - | |
11 | 25.61 | C23H26O10 | 463.1579/ 480.1841 | 301.1068 [M + H-Glc]+ | 273.1120, 269.0812, 241.0858, 191.0705, 167.0700, 152.0472, 147.0441, 123.0449 | Astraperocarpan-3-O-Glc (9,10-dimethoxypterocarpan-3-O-Glc) | [12] | |
16 * | 29.81 | C26H28O13 | 549.1584/ 566.1846 | 301.1055 [M + H-Glc-Mal]+ | 513.1484, 495.1268, 409.1266, 273.1120, 269.0803, 241.0858, 191.695, 167.0690, 152.0467, 147.0441, 123.0445 | Astraperocarpan-3-O-Glc-6′-O-Mal | [12,22] | |
17 | 30.24 | C26H28O13 | 549.1582/ 566.1847 | 301.1067 [M + H-Glc-Mal]+ | 513.1564, 495.1265, 409.1257, 273.1117, 269.0809, 241.0868, 191.0704, 167.696, 152.0466, 147.0445, 123.0452 | Isomer astraperocarpan-3-O-Glc- 6′-O-Mal | - | |
20 | 33.58 | C16H14O5 | 287.0911 | - | 259.0975, 255.0656, 227.0677, 177.0552, 153.0554, 147.0448, 138.321, 123.0456 | Vesticarpan (3,10-dihydroxy-9- methoxypterocarpan) | [26] | |
24 | 40.91 | C17H16O5 | 301.1064/- | - | 273.1116, 269.0860, 241.0863, 191.0705, 167.0695, 152.0471, 147.0445, 123.0447 | 3-hydroxy-9,10- dimethoxypterocarpan | [12,24] |
Analyte | Linearity | LOD (ug·mL−1) | LOD (ug·mL−1) | Precision (RSD, %) | |||
---|---|---|---|---|---|---|---|
Calibration Curve | R | Range (ug·mL−1) | Inter-Day (n = 3) | Intra-Day (n = 3) | |||
Calycosin-7-O-Glc (CYG) | Y = 19248X + 18515 | 0.9993 | 1.298~811.4 | 0.038 | 0.226 | 1.96 | 4.75 |
Calycosin-7-O-Glc-6″-O-Mal (CYM) | Y = 13926X + 3619 | 0.9995 | 0.672~420.0 | 0.047 | 0.280 | 2.21 | 5.63 |
Calycosin (CY) | Y = 29328X + 4448 | 0.9992 | 0.383~239.1 | 0.026 | 0.085 | 0.83 | 2.38 |
Formononetin-7-O-Glc (FMG) | Y = 16433X + 3925 | 0.9992 | 0.464~290.1 | 0.037 | 0.220 | 1.88 | 4.82 |
Formononetin-7-O-Glc-6″-O-Mal (FMM) | Y = 14361X + 4344 | 0.9987 | 0.576~360.0 | 0.039 | 0.235 | 2.04 | 5.35 |
Formononetin (FM) | Y = 26510X + 8997 | 0.9983 | 0.470~294.0 | 0.028 | 0.092 | 0.85 | 2.62 |
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Zheng, Y.; Duan, W.; Sun, J.; Zhao, C.; Cheng, Q.; Li, C.; Peng, G. Structural Identification and Conversion Analysis of Malonyl Isoflavonoid Glycosides in Astragali Radix by HPLC Coupled with ESI-Q TOF/MS. Molecules 2019, 24, 3929. https://doi.org/10.3390/molecules24213929
Zheng Y, Duan W, Sun J, Zhao C, Cheng Q, Li C, Peng G. Structural Identification and Conversion Analysis of Malonyl Isoflavonoid Glycosides in Astragali Radix by HPLC Coupled with ESI-Q TOF/MS. Molecules. 2019; 24(21):3929. https://doi.org/10.3390/molecules24213929
Chicago/Turabian StyleZheng, Yunfeng, Weiping Duan, Jie Sun, Chenguang Zhao, Qizhen Cheng, Cunyu Li, and Guoping Peng. 2019. "Structural Identification and Conversion Analysis of Malonyl Isoflavonoid Glycosides in Astragali Radix by HPLC Coupled with ESI-Q TOF/MS" Molecules 24, no. 21: 3929. https://doi.org/10.3390/molecules24213929