Table 3.
HPLC-MS/MS determination of polyphenolic compounds and antioxidant activity in the maceration, SFE and EA-SFE extracts of M. sativa leaves.
| HPLC-MS/MS Determination | |||||
|---|---|---|---|---|---|
| Compound | tR (min) | MRM | Concentration (µg/g) | ||
| Maceration | SFE (Control) |
EA-SFE (Optimal Conditions) | |||
| Phenolic acids | |||||
| Gallic acid + | 2.138 | 169–124 | ND a | ND | ND |
| Salicylic acid + | 3.961 | 137–93 | 6.79 ± 0.62 | 26.50 ± 2.94 | 100.48 ± 2.53 |
| p-Coumaric acid + | 3.450 | 163–119 | 0.83 ± 0.34 | 1.34 ± 0.33 | 3.78 ± 0.10 |
| Chlorogenic acid + | 2.681 | 353–191 | ND | 0.32 ± 0.14 | 0.13 ± 0.04 |
| Caffeic acid + | 3.036 | 179–135 | 0.59 ± 0.22 | 0.92 ± 0.05 | 2.44 ± 0.11 |
| Syringic acid + | 3.118 | 197–95 | 3.34 ± 0.99 | 4.73 ± 1.12 | 14.74 ± 2.77 |
| Ferulic acid + | 3.566 | 193–134 | 56.36 ± 9.43 | 126.93 ± 6.99 | 277.41 ± 7.87 |
| Protocatechuic acid + | 2.482 | 153–108 | 11.72 ± 2.78 | 2.82 ± 0.12 | 5.73 ± 1.89 |
| Sinapic acid + | 3.553 | 223–121 | 3.03 ± 1.65 | 7.88 ± 3.57 | 9.28 ± 0.39 |
| 4-Hydroxybenzoic acid + | 2.890 | 137–65 | 4.48 ± 1.07 | 6.17 ± 2.22 | 20.80 ± 2.76 |
| ⅀ | 87.14 ± 17.10 | 177.61 ± 17.48 | 434.78 ± 18.46 | ||
| Flavonoids | |||||
| Flavone ++ | 5.452 | 223–121 | 0.01 ± 0.00 | 0.23 ± 0.02 | 0.16 ± 0.01 |
| Fisetin + | 3.928 | 285–121 | ND | ND | ND |
| Kaempferol + | 4.811 | 285–255 | ND | ND | ND |
| Apigenin + | 4.730 | 269–117 | 63.09 ± 1.33 | 87.48 ± 4.32 | 95.53 ± 1.19 |
| Luteolin + | 4.359 | 285–133 | 9.12 ± 0.48 | 5.15 ± 0.23 | 9.86 ± 1.09 |
| Rutin + | 3.447 | 609–300 | 0.62 ± 0.12 | 0.92 ± 0.13 | 0.49 ± 0.17 |
| Quercetin + | 4.382 | 301–227 | 0.02 ± 0.00 | 0.61 ± 0.04 | 1.02 ± 0.23 |
| Naringin + | 3.528 | 579–271 | ND | ND | 0.15 ± 0.01 |
| Naringenin + | 4.744 | 271–119 | 1.39 ± 0.70 | 2.09 ± 0.13 | 2.53 ± 0.10 |
| Esculin + | 2.492 | 339–177 | ND | 0.01 ± 0.00 | 0.01 ± 0.00 |
| Esculetin + | 3.053 | 177–89 | 0.41 ± 0.06 | 0.37 ± 0.11 | 1.10 ± 0.13 |
| Biochanin A + | 5.666 | 283–211 | 0.06 ± 0.01 | 0.21 ± 0.04 | 0.21 ± 0.01 |
| Catechin + | 3.012 | 289–123 | ND | ND | ND |
| ⅀ | 74.72 ± 2.70 | 97.07 ± 5.02 | 111.06 ± 2.94 | ||
| ⅀ | 161.86 ± 19.80 | 274.68 ± 22.50 | 545.84 ± 21.40 | ||
| Antioxidant activity | |||||
| AgNP method (µmol AP/g DW) | 22.91 ± 0.81 | 20.50 ± 0.81 | 27.36 ± 0.75 | ||
| DPPH method (µmol TEAC/g DW) | 0.85 ± 0.01 | 0.97 ± 0.02 | 1.71 ± 0.08 | ||
a ND—not detected; +—negative ionization mode; ++—positive ionization mode. All results were expressed as mean ± standard deviation (n = 3) in µg per gram of dry leaves; SFE—supercritical fluid extraction; EA-SFE—enzyme-assisted supercritical fluid extraction; AP- apigenin; TEAC—Trolox.