Table 1.
Quantitative assessment of total phenolics, total phenolic acids and individual phenolic markers in comfrey (S. officinale) roots collected from different European regions and stored for 1–6 months.
| Storage Period (Months) |
TPC | TPAC | Rosmarinic Acid | Globoidnan A | Globoidnan B | Rabdosiin |
|---|---|---|---|---|---|---|
| mg GAE/g d.w. Root | mg CAE/g d.w. Root | mg/g d.w. root | ||||
| Sample FS | ||||||
| M1 | 9.24 ± 0.01 a | 3.70 ± 0.09 a | 3.09 ± 0.05 a | 2.29 ± 0.10 a | 1.60 ± 0.07 a | 0.38 ± 0.01 a |
| M2 | 8.40 ± 0.17 b | 5.05 ± 0.17 b | 1.89 ± 0.04 b | 1.87 ± 0.06 a | 0.96 ± 0.04 b | 0.28 ± 0.01 b |
| M3 | 11.12 ± 0.21 c | 4.94 ± 0.18 b | 2.63 ± 0.07 c | 3.15 ± 0.26 b | 0.80 ± 0.07 b | 0.38 ± 0.02 a |
| M6 | 6.48 ± 0.08 d | 2.67 ± 0.19 c | 1.65 ± 0.03 b | 1.24 ± 0.13 c | 0.80 ± 0.07 b | 0.14 ± 0.02 c |
| Sample IS | ||||||
| M1 | 8.67 ± 0.21 b | 2.87 ± 0.13 c | 1.81 ± 0.06 b | 3.17 ± 0.18 b | 1.50 ± 0.10 a | 0.52 ± 0.03 d |
| M2 | 10.30 ± 0.02 c | 4.15 ± 0.57 d | 1.40 ± 0.01 c | 3.20 ± 0.08 b | 0.65 ± 0.03 c | 0.41 ± 0.05 a |
| M3 | 11.08 ± 0.17 c | 5.11 ± 0.31 b | 1.41 ± 0.04 c | 2.43 ± 0.05 a | 0.87 ± 0.02 b | 0.39 ± 0.01 a |
| M6 | 10.25 ± 0.21 c | 4.34 ± 0.31 b,d | 1.37 ± 0.07 c | 1.99 ± 0.17 a | 1.12 ± 0.07 d | 0.30 ± 0.01 b |
| Sample NT | ||||||
| M1 | 16.57 ± 0.15 e | 9.03 ± 0.16 e | 4.51 ± 0.22 d | 3.34 ± 0.33 b | 0.50 ± 0.01 c | 0.85 ± 0.07 e |
| M2 | 12.85 ± 0.13 c | 5.73 ± 0.08 f | 3.60 ± 0.35 e | 3.60 ± 0.35 b | 1.05 ± 0.09 d | 0.87 ± 0.11 e |
| M3 | 15.47 ± 0.17 e | 6.54 ± 0.32 g | 5.05 ± 0.12 f | 2.55 ± 0.22 a | 0.86 ± 0.08 b | 0.88 ± 0.08 e |
| M6 | 8.68 ± 0.04 b | 3.74 ± 0.25 a | 2.82 ± 0.05 a | 1.37 ± 0.08 c | 0.57 ± 0.01 c | 0.42 ± 0.02 a |
| Sample CH | ||||||
| M1 | 8.42 ± 0.01 b | 4.07 ± 0.13 b | 4.98 ± 0.08 f | 2.33 ± 0.25 a | 2.50 ± 0.26 e | 1.26 ± 0.09 f |
| M2 | 6.85 ± 0.05 d | 3.00 ± 0.14 c | 4.26 ± 0.12 d | 3.27 ± 0.11 b | 1.25 ± 0.04 d | 0.97 ± 0.04 e |
| M3 | 10.27 ± 0.21 c | 4.82 ± 0.28 b | 4.22 ± 0.17 d | 2.54 ± 0.53 a | 1.66 ± 0.30 a | 1.03 ± 0.19 e |
| M6 | 7.65 ± 0.28 f | 3.67 ± 0.01 a | 3.50 ± 0.09 e | 1.59 ± 0.05 c | 1.53 ± 0.02 a | 0.70 ± 0.04 g |
| Sample PL | ||||||
| M1 | 8.61 ± 0.05 b | 3.43 ± 0.27 a | 1.74 ± 0.02 b | 1.11 ± 0.03 c | 0.47 ± 0.02 c | 0.90 ± 0.05 e |
| M2 | 6.95 ±0.17 d | 2.91 ± 0.10 c | 1.26 ± 0.07 c | 0.78 ± 0.03 d | 0.31 ± 0.01 f | 0.57 ± 0.06 d |
| M3 | 9.63 ± 0.10 g | 4.27 ± 0.37 d | 1.66 ± 0.14 b | 0.97 ± 0.15 d | 0.33 ± 0.06 f | 0.70 ± 0.15 d,e |
| M6 | 10.55 ± 0.13 c | 4.26 ± 0.11 d | 1.23 ± 0.05 c | 0.90 ± 0.05 c,d | 0.43 ± 0.02 c | 0.64 ± 0.03 d |
Data are presented as mean ± standard deviation (SD) of three determinations; values sharing different superscripts within columns are significantly different at p < 0.05 (Tukey’s test); CAE, caffeic acid equivalents; GAE, gallic acid equivalents; TPAC; total phenolic acid content; TPC, total phenolic content.