Table 2.
Detection and identification of flavonoids in the leaves of E. guineensis and their TPC and TFC values.
| Reference | Methods for Detecting and Identifying Flavonoids | Types of Flavonoids | TPC (mg GAE g−1 Sample or Extract) | TFC |
|---|---|---|---|---|
| [2] | N/R | N/R | INSOL fraction: 118.44 ± 0.0 9BHT (positive control): 116.22 ± 0.04 MeOH extract: 63.67 ± 0.14 WATER extract: 61.13 ± 0.28 EA extract: 44.03 ± 0.03 HEX extract: 16.96 ± 0.13 |
N/R |
| [4] | FTIR Spectroscopy | Flavonoids | Moderately high phenolic content of the aqueous methanolic extract: 0.33 | N/R |
| [18] | HPLC | Luteolin | MeOH extract: 24.3 ± 1.7 Green text extract: 22.5 ± 1.7 |
N/R |
| [19] | HPLC | (−)-Epigallocatechin, (+)-catechin, (−)-epicatechin, (−)-epigallocatechin gallate, (−)-epicatechin gallate, and their glucosides | N/R | N/R |
| [20] | N/R | N/R | Extract prepared from dried leaves: 10.2 Extract prepared from wet leaves: 5.1 |
N/R |
| [11] | N/R | N/R | OPAL M1: 1.160 ± 0.001 OPAL M2: 0.982 ± 0.001 OPAL M3 0.304 ± 0.044 OPAL M4: 0.440 ± 0.006 Classification refers to Table S1. |
OPAL M1: 1.16 ± 0.001 c OPAL M2: 0.55 ± 0.002 c OPAL M3 0.30 ± 0.002 c OPAL M4: 0.33 ± 0.001 c |
| [21] | UHPLC-UV/PDA LCMS/MS |
Major compounds: orientin, isoorientin, vitexin, isovitexin Minor compounds: luteolin-6-8-di-C-hexose, apigenin-6,8-di-C-hexose, luteolin-6-8-di-C-hexose, apigenin-6-C-pentose-8-C-hexose, apigenin-6-C-hexose-8-C-pentose, luteolin-6-C-hexose-8-C-deoxyhexose, and apigenin-6-C-hexose-8-C-deoxyhexose. |
N/R | N/R |
| [22] | NMR Spectroscopy | (+)-Catechin, vitexin, isovitexin, orientin, isoorientin, and (−)-epicatechin | Aqueous methanol extract: 393.61 ± 36.11 Absolute methanol extract: 213.08 ± 41.61 Ethyl acetate-methanol extract: 174.19 ± 32.40 Ethyl acetate extract: 121.71 ± 32.78 |
Aqueous methanol extract: 129.72 ± 8.70 b Absolute methanol extract: 135.40 ± 9.76 b Ethyl acetate-methanol extract: 121.48 ± 6.67 b Ethyl acetate extract: 5.94 ± 5.38 b |
| [23] | Phytochemical qualitative analysis | Flavonoids | Ethanol extract: 52.4 | Ethanol extract: 15.4 a |
| [5] | Phytochemical qualitative analysis | Flavonoids | N/R | N/R |
TPC: Total Phenolic Content; TFC: Total Flavonoid Content. Superscript: a indicates (mg CE g−1 extract). b indicates (mg QCE g−1 extract). c indicates (mg ECE g−1 sample).