Table 2.
Quality control and chemical analysis of rhubarb extracts
| No. | Extracts | Species | Part | Method | Quality control | Refs. |
|---|---|---|---|---|---|---|
| 1 | 50% ethanol extract | R. palmatum L. | Root | Column chromatography; HPLC | Aloe-emodin, rhein, emodin, chrysophanol, physcion | [107] |
| 2 | – | R. palmatum L. | Rhizome | – | Aloe-emodin (0.11%), rhein (0.37%), emodin (0.05%), chrysophanol (0.36%), physcion (0.26%) | [14] |
| 3 | Methanol extract | R. palmatum L. (Three-year-old; harvested in September) | Root | HPLC | Aloe-emodin (0.21%), rhein (0.21%), emodin (0.37%), chrysophanol (1.09%), physcion (0.24%) | [108] |
| 4 | Methanol extract | R. palmatum L. (Three-year-old; harvested in September) | Root | 1H-NMR | Aloe-emodin (0.23%), rhein (0.19%), emodin (0.38%), chrysophanol (1.26%), physcion (0.23%) | [108] |
| 5 | – | R. tanguticum Maxim. | Rhizome | – | Aloe-emodin (2.09%), rhein (0.001%), emodin (0.001%), chrysophanol (0.08%), physcion (0.07%) | [14] |
| 6 | – | R. officinale Baill. | Rhizome | – | Rhein (0.001%), chrysophanol (0.09%), physcion (0.09%) | [14] |
| 7 | Methanol extract | – | Root | RP-HPLC | Aloe-emodin, rhein, emodin, chrysophanol, physcion | [109] |
| 8 |
Chloroform extract |
– | – | MEEKC | Aloe-emodin (2.04%), rhein (0.5%), emodin (1.58%), chrysophanol (5.06%), physcion (0.98%) | [110] |
| 9 |
95% ethanol and chloroform extract |
– | – | DryLab software-aided RP-HPLC | Aloe-emodin (0.15%), rhein (0.03%), emodin (0.09%), chrysophanol (0.52%), physcion (0.05%) | [111] |
| 10 |
Chloroform extract |
– | – | DryLab software-aided RP-HPLC | Aloe-emodin (0.33%), rhein (0.07%), emodin (0.20%), chrysophanol (1.02%), physcion (0.18%) | [111] |
| 11 | Water extract | – | – | UPLC/Q-TOF-MS/MS | Aloe-emodin (0.14%), rhein (0.31%), emodin (0.24%), chrysophanol (0.37%), physcion (2.69%) | [112] |
| 12 | Ethanol-chloroform extract | – | – | LC–MS | Rhein, physcion, emodin | [113] |
| 13 | Methanol extract | – | – | BC-SOS-LPME coupled with HPLC–UV | Rhein (0.6%), chrysophanol (2.53%) | [114] |
| 14 | Methanol extract | Rhei Rhizoma | – | HPLC–UV-MS | Aloe-emodin (0.24%), rhein (0.13%), emodin (0.11%), chrysophanol (0.31%), physcion (0.13%) | [115] |
| 15 | 80% methanol extract |
R. officinale; R. palmatum; R. Tanguticum |
– | UPLC-PDA | Aloe-emodin-8-O-glucoside, rhein-8-O-glucoside, chrysophanol-1-O-glucoside, emodin-1-O-glucoside, chrysophanol-8-O-glucoside, emodin-8-O-glucoside | [116] |
| 16 | Methanol extract | R. undulatum L. | Rhizome |
Diaion HP-20 column chromatography; silica gel column chromatography; ODS column chromatography; HPLC |
Chrysophanol-8-O-β-d-(6′-galloyl)-glucopyranoside, aloe-emodin-1-O-β-d-glucopyranoside, chrysophanol-1-O-β-d-glucopyranoside, chrysophanol-8-O-β-d-glucopyranoside | [117] |
| 17 | Ethanol extract | Korean rhubarb | Rhizome | Silica gel column chromatography | Chrysophanol, physcion, emodin, chrysophanol-8-O-β-d-glucopyranoside, emodin-8-O-β-d-glucopyranoside | [118] |
| 18 | Ethanol extract | Korean rhubarb | Rhizome | Silica gel column chromatography | Chrysophanol-8-O-β-d-glucopyranoside, chrysophanol | [119] |
| 19 | 70% ethanol extract | R. crispus | Rhizome | HPLC | Emodin-glucoside (0.006%), emodin (0.12%), chrysophanol (0.39%) | [9] |
| 20 | 50% ethanol extract | R. likiangense Sam. | Rhizome | HSCCC | Rhaponticin, desoxyrhaponticin | [120] |
| 21 | Ethanol extract | – | Rhizome | Silica gel column chromatography | Piceatannol-3′-O-β-d-glucopyranoside | [121] |
| 22 | Ethanol extract | Korean rhubarb | Rhizome | Silica gel column chromatography | Desoxyrhaponticin, rhaponticin, resveratrol, desoxyrhapotigenin, rhapontigenin, piceid, ε-viniferin, piceatannol-3′-O-β-d-glucopyranoside, ampelopsin B, isorhaponticin | [118] |
| 23 | Acetone extract |
Garden rhubarb (hybrids of R. rhabarbarum L. and R. rhaponticum L.) |
Rhizome |
MLCCC; HPLC; NMR; HR-MS; HPLC–DAD |
Trans-rhapontigenin, trans-desoxyrhapontigenin, trans-rhaponticin, trans-desoxyrhapontici, trans-piceatannol-3′-O-β-d-glucopyranoside, trans-resveratrol-4′-O-β-d-glucopyranoside | [122] |
| 24 | Methanol extract | Rhei Rhizoma | – | HPLC–UV-MS | Resveratrol-4’-O-β-d-glucopyranoside, resveratrol-4′-O-β-d-(2′’-O-galloyl)-glucopyranoside, resveratrol 4’-O-β-d-(6’’-O-galloyl)-glucopyranoside | [115] |
| 25 | 80% ethanol extract | R. undulatum L. | Rhizome | Chromatography | Desoxyrhapontigenin | [123] |
| 26 | Methanol extract | R. undulatum L. | Rhizome | – | Rhaponticin, rhaponticin 2’’-O-gallate, isorhapontin, piceatannol 3’-O-Glc, rhapontigenin, resveratrol, isorhapontigenin, piceatannol, desoxyrhapontigenin | [124] |
| 27 | Methanol extract | Rhei Rhizoma | – | – | Rhubarb galloyl (RG)-tannin | [125] |
| 28 | Methanol extract | R. tanguticum Maxim. | Rhizome | Reversed phase gel column chromatography | RG-Tannin (3.15%), rhatannin (0.005%) | [14] |
| 29 | Methanol extract | R. palmatum L. | Rhizome | Reversed phase gel column chromatography | RG-Tannin (3.49%), rhatannin (0.85%) | [14] |
| 30 | Methanol extract | R. officinale Baill. | Rhizome | Reversed phase gel column chromatography | RG-Tannin (1.74%), rhatannin (0.004%) | [14] |
| 31 |
Methanol/ chloroform extract |
R. emodi | Rhizom; root | Column chromatography; TLC | – | [126] |
| 32 | Methanol extract | rhaponticum L. | Petiole | RP-HPLC–UV-ESI/MS2 | Myricetin-O-rhamnoside, quercetin-O-rutinoside (rutin), quercetin-O-glucoside, quercetin-O-glucuronide, quercetin-O-glucuronide, quercetin | [127] |
| 33 | Acetone extract |
Garden rhubarb (hybrids of R. rhabarbarum L. and R. rhaponticum L.) |
Leaves; petiole |
MLCCC; HPLC; NMR; HR-MS; HPLC–DAD |
6,8-di-C-β-d-glucosylapigenin, 6-C-β-d-glucosyl-8-C-β-d-arabinosylapigenin, rutin, 6-C-β-d-arabinosyl-8-C-β-d-glucosylapigenin, quercetin-3-O-β-d-glucuronide, isovitexin | [122] |
| 34 | Methanol extract | Rhei Rhizoma | – | HPLC–UV-MS | Sennidin A (1.12%), sennidin B (0.37%) | [115] |
| 35 | – |
Hokkai Daio |
Root | Eastern blotting | Sennidin A phloem (0.00584%), radiate wood (0.0049%), pith (0.00133%) | [128] |
| 36 | – | R. australe D. Don | Root | Column chromatography | Carpusin, maesopsin | [129] |
| 37 | Methanol extract | R. undulatum L. | Rhizome |
Diaion HP-20 column chromatography; silica gel column chromatography; ODS column chromatography; HPLC |
Torachrysone 8-O-β-d-glucopyranoside | [117] |
| 38 | n-pentane and diethyl ether extract | R. rhabarbarum L. | Stalk | VHS; GC–MS; GC | Alcohols, aldehydes, esters, ketones, acids sesquiterpenes, terpenes, phenolic derivatives | [130] |
| 39 | Methanol extract |
nanum; R. Racemiferum; delavay; pumilum; R. sublanceolatum |
– | HPLC–DAD-ESI-MSn | Sennosides, anthraquinones, stilbenes, glucose gallates, naphthalenes, procyanidins, chromones | [131] |
| 40 | Methanol extract | Rhei Rhizoma | – | HPLC–UV-MS | Gallic acid (0.26%) | [115] |
| 41 | 95% ethanol extract | – | Root; stem | CCC; LC/MS | Tannins and gallic acid | [132] |
| 42 | Ethanol extract | R. palmatum L. | Rhizom; root | HPLC | – | [133] |
| 43 | Methanol extract | R. undulatum L. | Rhizome | Silica gel column chromatography | 5-methoxy-cis-rhapontigenin, 5-methoxy-trans-rhapontigenin, resveratrol, piceatannol, deoxyrhapontigenin, rhapontigenin, piceatannol, resveratroloside, δ-viniferin | [134] |
| 44 | Methanol extract | R. emodi Wall.ex Meisson | Rhizome | Silica gel column chromatography | Desoxyrhapontigenin, desoxyrhaponticin, chrysophanol-8-O–β-d-glucopyranoside, rhapontigenin, torachrysone-8-O-β-d-glucopyranoside | [135] |
| 45 | Methanol extract | R. rhaponticum L. | Root | RP-HPLC- UV-ESI/MS2 | Piceatannol glucoside-1, piceatannol glucoside-2, resveratrol glucoside-1, piceatannol glucoside-3, rhapontin-1, resveratrol galloylglucoside, emodin, rhapontigenin, galloylglucoside, deoxyrhapontin, torachrysone glucoside, emodin glucoside, chrysophanol glucoside, deoxyrhapontigenin galloylglucoside, resveratrol dimer-1, resveratrol dimer-2 | [127] |
| 46 | 70% ethanol extract | R. officinale Baill. | Rhizome | HPLC | Sennoside A (0.33%), emodin-glucoside (0.04%), chrysophanol (0.21%), emodin (0.03%) | [9] |
| 47 | 70% ethanol extract | R. palmatum L. | Rhizome | HPLC | Sennoside A (0.15%), emodin-glucoside (0.03%), chrysophanol (0.63%), emodin (0.19%) | [9] |
| 48 | 70% ethanol extract | R. tanguticum Maxim. | Rhizome | HPLC | Sennoside A (0.56%), emodin-glucoside (0.05%), chrysophanol (0.38%), emodin (0.11%) | [9] |
| 49 | 70% ethanol extract | R. undulatum L. | Rhizome | HPLC | Rhaponticin (5.45%), emodin-glucoside (0.097%), emodin (0.049%), chrysophanol (0.464%) | [9] |
| 50 | 70% ethanol extract | – | – | UPLC/Q-TOF–MS/MS; chromatographic fingerprints | Aloe-emodin, rhein, emodin, chrysophanol, physcion, catechin, gallic acid, methyl gallate, ethyl gallate, torachrysone, hydroxy physcion, 3,5,4’-trihydroxy-transstilbene, sennoside A, solindleyin, ect | [136] |
| 51 | Methanol extract |
R. officinale; R. palmatum; R. emodi; R. tanguticum; R. franzenbachii; R. hotaoense; |
Root | Liquid chromatography coupled with electrospray ionization tandem mass spectrometry | Aloe-emodin, rhein, emodin, chrysophanol, physcion, emodin 8-O-glucoside, chrysophanol 8-O-glucoside, sennoside A, rhaponticin, epi-catechin, ect | [16] |
| 52 | Methanol extract | R. palmatum L. | – | Ultra-performance liquid; PLC/Q-TOF–MS | Emodin-8-O-glucoside, emodin-O-glucoside, catechin-glucopyranoside, gallic acid-3-O-glucoside, torachrysone, chrysophanol dimethylether | [137] |
| 53 | 70% methanol extract | R. palmatum L. | – | LC–QTOF MS | Rhapontigenin, rhein, resveratrol, cinnamoyl, chrysophanol, physcion, emodin, aloe-emodin, anthranone, dianthrone, etc | [138] |
| 54 | Water–acetone extract | R. rhabarbarum L. | Stalk |
LDI-MSI with gold nanoparticle -enhanced target (AuNPET) |
Emodin, aloe-emodin, chrysophanol, citreorosein, citreorosein, sennoside E and F, resveratrol, trans-stilbene, rhaponticin, piceatannol 4’-galloylglucoside, quercetin, oxalic acid, succinic acid, carvacrol, dehydroascorbic acid, pcoumaric acid, lysine, chromene, paeonol, vitamin B5 and D1, amino acids threonine, phenylalanine, digalloyl-substituted, procyanidin B2 and B5, gallic acid, magnesium oxalate, ect | [139] |
| 55 | Ethanol extract | R. palmatum L. | – | HPLC coupled with photodiode array detector | Gallic acid, catechins, epicatechin gallate, chrysophanol (> 0.07%), epigallocatechin gallate, epicatechin, sennoside A, sennoside B, aloe-emodin, rhein, emodin, physcion (< 0.04%) | [140] |
| 56 | 70% methanol extract | R. tanguticum Maxim.ex Balf. | – | HPLC-LTQ-Orbitrap-MS | Emodin, rhein, physcion, aloe-emodin, chrysophanol, (+)-catechin, sennoside A, sennoside B, sennoside C, polydatin, gallic acid, emodin- 8-O-β-d-glucopyranoside, aloe-emodin-8-O-glucoside, epicatechin-3-O-gallate, etc | [141] |
| 57 | Methanol extract | R. tanguticum Maxim.ex Balf. | – | UPLC/Q-TOF–MS/MS |
p-coumaric acid glucoside, (−) epicatechin-3-O-gallate, isolindleyin, phlorizin, emodin, aloe-emodin, emodin-1-O-β-d-glucopyranoside, 4-(4′-hydroxyphenyl)-2-butanone 4′-O-β-d-(6-O-trans-p-coumaroyl)-glucopyranoside, resveratrol-4′-O-β-d-(2′′-O-galloyl)-glucopyra-noside, etc |
[142] |
| 58 | Methanol extract | – | – | UHPLC |
Sennoside A, physcion, rhein, chrysophanol, aloe-emodin, emodin, aloe-emodin-8-O-β-d-glucopyranoside, rhein-8-O-β-d-glucopyranoside, emodin-8-O-β-d-glucopyranoside, chrysophanol-8-O-β-d-glucopyranoside, physcion-8-O-β-d-glucopyranoside |
[143] |
| 59 | 80% methanol extract | R. palmatum L.; R. tanguticum Maxim.ex Balf.; R. Officinale Baill. | – |
HPLC coupled with PDA |
Physcion, rhein, aloe-emodin, emodin, chrysophanol, gallic Acid, sennoside A, sennoside B, catechins, epicatechin, epigallocatechin gallate, epicatechin gallate | [144] |