Table 1.
Selected high-resolution MS applications in the characterization of Ephedra species compounds (published in the period 2015–2019).
| Source | Part | Solvent | Analyte | Mobile phase and gradient program | Analytical method | Detection (nm) | Reference |
|---|---|---|---|---|---|---|---|
| Tunisia | Aerial parts of E. alata Decne | 70% EtOH | Gallic acid, protocatechuic acid, caffeic acid, epicatechin, p-coumaric acid, ferulic acid, rutin, rosmarinic acid, resveratrol, quercetin and kaempferol | A: water acidified with formic acid at pH 3; B: acetonitrile acidified with formic acid at pH 3 : 0.01–20 min, 5% B; 20.01–50 min, 5–40% B; 50–55 min, 40–95% B; and 55–60 min 95% B | LC-MS | 280–320 | [90] |
| Aerial parts of E. alata | EtOH/water (50 : 50 v/v) | Quinic acid, gallic acid, 4-O-caffeoylquinic acid, syringic acid, p-coumaric acid, trans-ferulic acid, catechin, epicatechin, rutin, quercitrin (quercetin-3-O-rhamnoside), apigenin-7-O-glucoside, kaempferol, naringenin, luteolin, cirsilineol | The mobile phase was composed of A (0.1% formic acid in H2O, v/v) and B (0.1% formic acid in methanol, v/v): linear gradient elution: 0–45 min, 10–100% B; 45–55 min, 100% B | LC-ESI/MS/MSn | 280 | [23] | |
| Aerial parts of E. alata | 70% MeOH then fractionation with hexane, DCM, EAc BuOH, and water | Quinic acid (1), gallic acid (2), protocatechuic acid (3), chlorogenic acid (3-O-caffeoylquinic acid) (4), caffeic acid (5), syringic acid (6), p-coumaric acid (7), trans-ferulic acid (8), o-coumaric acid (9), transcinnamic acid (10), 4-O-caffeoylquinic acid (11), 1,3-di-O-caffeoylquinic acid (12), 3,4-di-O-caffeoylquinic acid (13), 4,5-di-O-caffeoylquinic acid (14), rosmarinic acid (15), salvianolic acid (16), (+)-catechin (17), (−)-epicatechin (18), acacetin (19), apigetrin (apigenin-7-O-glucoside) (20), apigenin (21), quercitrin (quercetin-3-o rhamnoside) (22), kaempferol (23), cirsilineol (24), cirsiliol (25), hyperoside (quercetin-3-O-galactoside) (26), cynaroside (luteolin-7-O-glucoside) (27), luteolin (28), Naringenin (29), naringin (naringenin-7-O-rutinoside) (30), quercitrin (quercetin-3-O-rhamnoside) (31), rutin (quercetin-7-O-rutinoside) (32), and silymarin (33) |
The mobile phase: A (0.2% acetic acid in 95% water and 5% MeOH) and B (0.2% acetic acid in 50% water and 50% acetonitrile) with a linear gradient elution: 0–45 min, 10–20% B; 45–85 min, 20–55% B; 85–97 min, 55–100% B; 97–110 min, 100% B; the initial conditions were held for 10 min as a re-equilibration step | HPLC-PDA-ESI/MS | (1) 240; (2) 272–218; (3) 259–294-220; (4)230–280; (5) 327–245-295; (6) 327–295-245; (7) 324–295-220; (8) 274–220; (9) 322–302–245–218; (10) 230–279; (11) 309–229-298; (12) 322–240-295; (13) 255–356; (14) 355–256; (15) 275–325-230; (16) 347–253-267; (17) 329–295–245–221; (18) 329–290-245; (19) 329–290-245; (20) 212–226–282–328; (21) 336–67; (22) 325–295–245–221; (23) 287–254–309–228; (24) 275–222-215; (25) 275–365; (26) 254–290- 366; (27) 228–288-332; (28) 337–267-225; (29) 287–231; (30) 347–253-266; (31) 344–273-225; (32) 343–247-225; and (33) 331–268 | [45] | |
| Algeria | Whole plant E. alata Decne ssp. alenda | - Infusion - Decoction - 80% EtOH |
10 phenolic compounds: 2 myricetin-C-hexoside isomers (1 and 2); biochanin A 7-O-glucoside (Sissotrin) (3); 2 hydroxydaidzein-8-C-glucoside isomers (4 and 5); 5,5′-dihydroxy-methoxy-isoflavone-O-glucoside (6); hydroxydaidzein-8-C-glucoside isomer (7); quercetin-3-O-rutinoside (8); isorhamnetin-3-O-glucoside (9); and kaempferol-O-di-deoxyhexoside (10) | (A) 0.1% formic acid in water, and (B) acetonitrile: 15% B (0–5 min), 15%–20% B (5–10 min), 20–25% B (10–20 min), 25–35% B (20–30 min), and 35–50% B (30–40 min) | LC-DAD-ESI/MSn | (1) 291, 340; (2) 290, 340 (3) 255, 320; (4) 262,340 (5) 262,340 ; (6) 263,336 (7) 262,340 ; (8) 351 (9) 368; and (10) 263,348 |
[100] |
| Austria | Aerial parts of E. sinica | PET, DCM, EtOAc n-BuOH, EtOH, MeOH, or water | Epigallocatechin-4β-benzylthioether, epigallocatechin-4-benzylthioether stereoisomers, and epicatechin-4β-benzylthioether |
A = water, B = acetonitrile. 0 min: 35% B, 20 min: 35% B, 30 min: 45% B, 40 min: 45% B, 45 min: 98% B60 min: S top; post- time 15 min |
HPLC and HPLC-MS | 254 | [101] |
| Austria/Germany | Aerial parts of 8 Ephedra spp. | HCl (6.2%, v/v) | Ephedrine and pseudoephedrine | Acetonitrile, tetrahydrofuran, and water (38 : 5:57, v/v/v) | UPLC-UV | 208 | [102] |
| Palestine | Aerial parts of E. alata | EtOH, EtOH (80%), and water | Luteolin-7-O-glucuronide, myricetin-3-rhamnoside | The start was a 100% (A) that descended to 70% (A) in 40 minutes, then to 40% (A) in 20 minutes, and finally to 10% (A) in 2 minutes and stayed there for 6 minutes and then back to the initial conditions in 2 minutes | HPLC/PDA and HPLC/MS | 350 | [41] |
| Iran | Green stems from E. major | MeOH (80%) | Ephedrine | A mixture of 0/1% phosphoric acid (pH 4), 25 mM SDS, and 40% acetonitrile (10 : 1 v/v) | HPLC | 210 | [42] |
| Pakistan | Aerial plant of E. intermedia | 70% EtOH and MeOH 70% | Ephedrine and pseudoephedrine | Buffer solution of H3PO4 at 0.25 M (pH 5.3), methanol, and acetonitrile in ratio 1 : 1: 8 | HPLC | 210 | [103] |
| Korea | Aerial parts of E. intermedia | 30% EtOH | Ephedrine and pseudoephedrine | 60% solvent A (0–25 min), 60–40% solvent A (25–35 min), 40% solvent A (35–40 min), 40–20% solvent A (40–50 min), and 20% solvent A (50–60 min) | HPLC-UVD | 210 and 254 | [104] |
| E. sinica | Distilled water for 22 h at 95 °C | Ephedrine (1), pseudoephedrine (2), rhein (3), aloe-emodin (4), emodin (5), chrysophanol (6), and physcion (7) | -For (1) and (2) the mixtures of HPLC-grade H2O buffered with 25 mM sodium dodecyl sulfate (solvent A) and acetonitrile (AcCN, solvent B) -For (3), (4), (5), (6), and (7) the mixtures of H2O, AcCN, and phosphoric acid (850 : 150 : 1) for 20 min - For (1) and (2): 60% solvent A for 40 min |
HPLC | (1) 215; (2) 215 (3) 254; (4) 254 (5) 254; (6) 254, and (7) 254 |
[105] | |
| Stems of E. intermedia | 70% EtOH | Ephedrine, pseudoephedrine, N-methylephedrine, N-methylpseudoephedrine, norephedrine, and norpseudoephedrine | Isocratic gradient 25 mM SDS in water (A) and acetonitrile (B) | HPLC-UV | 215 | [106] | |
| Japan | E. sinica | Water at 95°C | Syringin; kaempferol 3-O-rhamnoside 7-O-glucoside; isovitexin 2″-O-rhamnoside; cinnamic acid; 6-hydroxykynurenic acid; 6-methoxykynurenic acid | 0.1% formic acid in water (A) and 0.1% formic acid in methanol (B): 5% B (0–10 min), 5–75% B (10–70 min), 75–100% B (70–80 min), 100% B (80–90 min) | LC-PDA | 210 | [107] |
| E. sinica | Hot water at 95 °C for 1 h | Vicenin-2 and isovitexin 2″-O-rhamnoside | 0.1% formic acid (HCOOH) in water (A) − 0.1% HCOOH in MeOH (B) 5% B (0 min) ⟶ 50% B (40 min) ⟶ 100% B (50 min) ⟶ 100% B (55 min) ⟶ 5% B (55.1 min) ⟶ 5% B (60 min) | LC/Orbitrap MS | 200–400 | [108] | |
| Taiwan | Aerial parts of Ephedra | Boiling | Ephedrine, amygdalin, glycyrrhizic acid, and carvedilol | 5 mM NH4CH3CO2 (0.1% formic acid) as the aqueous phase (A) and 100% methanol (0.1% formic acid) as the organic phase (B); 20–70% B at 0–1 min, 70–90% B at 1–4 min, 90% B at 4–9 min, 90–20% B 9–10 min, 20% B at 10–13 min | UHPLC–MS/MS | [109] | |
| China | Aerial parts of Ephedra | Water | Norephedrine, norpseudoephedrine, ephedrine, pseudoephedrine, and methylephedrine | A mixture of KH2PO4 (20 mmol/L)-acetonitrile (96 : 4, v/v) | HPLC | 210 | [110] |
| Ephedra herb | ACN-ammonium acetate | Methylephedrine, ephedrine, and pseudoephedrine | Acetonitrile-ammonium acetate (pH 5.0; 0.195 M) (95 : 5, v/v) | HPLC | 208 | [111] | |
| Stems of E. sinica | EtOH, EtOAc, and BuOH | (S)–N-((1R,2S)-1-hydroxy-1-phenylpropan-2-yl)-5-oxopyrrolidine-2-carboxamide (1) and (3R)-3-O-β-D-glucopyranosyl-3-phenylpropanoic acid (2) | ∗CH3OH/H2O (23%, v/v) (1) ∗ 25% MeOH in H2O, containing 0.1% formic acid (2) |
LC/MSD | 280 | [112] |