Table 2.
Composition and content of phenolic acids and flavonoids in barley of different colors (μg/g).
| Types | Black Variety | Yellow Variety | Blue Variety | Purple Variety | |||||
|---|---|---|---|---|---|---|---|---|---|
| Free | Bound | Free | Bound | Free | Bound | Free | Bound | ||
| Phenolic acid | |||||||||
| Benzoic acids | Gallic acid | ND | ND | ND | 33.365 ± 0.487 a | ND | ND | ND | 15.879 ± 0.936 b |
| Protocatechuic acid | 4.044 ± 0.037 a | ND | 1.831 ± 0.018 c | ND | 2.377 ± 0.052 b | ND | ND | ND | |
| 2,4-Dihydroxybenzoic acid | ND | ND | ND | 1.458 ± 0.082 a | 1.317 ± 0.049 a | ND | 0.879 ± 0.024 b | ND | |
| Vanillic acid | 2.9 ± 0.105 a | ND | ND | ND | ND | 1.065 ± 0.074 a | ND | ND | |
| Syringic acid | ND | 74.926 ± 1.016 b | ND | 116.901 ± 2.056 a | ND | 0.799 ± 0.014 d | ND | 25.638 ± 0.745 c | |
| Salicylic acid | 0.733 ± 0.09 b | 1.3 ± 0.049 b | 0.773 ± 0.046 b | 1.483 ± 0.013 ab | 0.847 ± 0.026 b | 0.89 ± 0.033 c | 1.105 ± 0.013 a | 1.738 ± 0.036 a | |
| Benzoic acid | 1.096 ± 0.015 a | 84.454 ± 0.405 b | ND | 140.898 ± 1.081 a | 0.818 ± 0.013 b | 2.699 ± 0.026 d | ND | 29.596 ± 1.157 c | |
| Veratric acid | 1.795 ± 0.033 b | 11.78 ± 0.18 a | ND | 0.993 ± 0.017 d | ND | 4.332 ± 0.031 c | 2.051 ± 0.077 a | 8.442 ± 0.088 b | |
| Cinnamic acid | O-coumaric acid | 1.603 ± 0.021 a | 3.614 ± 0.016 a | ND | 2.267 ± 0.099 bc | ND | 1.812 ± 0.039 c | ND | 1.929 ± 0.024 c |
| Chlorogenic acid | 7.279 ± 0.26 a | ND | 4.085 ± 0.162 b | ND | 3.681 ± 0.165 b | 6.155 ± 0.8 a | ND | ND | |
| p-coumaric acid | ND | 11.922 ± 0.779 c | ND | 14.1 ± 0.322 b | ND | 583.539 ± 2.248 a | 1.675 ± 0.044 a | 6.912 ± 0.14 d | |
| Ferulic acid | ND | 1.01 ± 0.023 ab | ND | 1.08 ± 0.05 ab | ND | 1.274 ± 0.05 a | ND | 0.762 ± 0.007 b | |
| Total | 19.450 ± 0.335 a | 189.006 ± 1.323 c | 6.689 ± 0.565 c | 312.544 ± 2.165 b | 9.040 ± 0.191 b | 602.565 ± 2.097 a | 5.710 ± 0.041 c | 90.900 ± 1.745 d | |
| Total phenolic acid | 208.456 ± 2.034 c | 319.233 ± 1.483 b | 611.605 ± 2.656 a | 96.605 ± 1.023 d | |||||
| Flavone | |||||||||
| Hesperidin | Naringin | ND | 0.668 ± 0.015 c | ND | 8.066 ± 0.115 a | 0.794 ± 0.005 b | 6.178 ± 0.104 b | 1.832 ± 0.036 a | 1.131 ± 0.029 c |
| Flavanol | Catechin | 6.458 ± 0.145 a | 3.225 ± 0.097 a | 5.693 ± 0.198 b | ND | ND | ND | ND | 3.53 ± 0.373 a |
| Chalcone | Phloretin | 33.078 ± 0.164 a | 1.047 ± 0.073 b | ND | ND | ND | ND | 1.324 ± 0.078 b | 3.895 ± 0.147 a |
| Flavanone | Hesperidin | ND | 5.564 ± 0.26 b | ND | 0.704 ± 0.005 d | ND | 2.002 ± 0.065 c | 2.856 ± 0.074 a | 9.688 ± 0.059 a |
| Naringenin | 0.724 ± 0.036 a | 5.31 ± 0.126 c | 0.616 ± 0.05 b | 4.728 ± 0.066 c | 0.625 ± 0.007 b | 50.145 ± 1.156 a | 0.698 ± 0.018 b | 8.547 ± 0.151 b | |
| Flavonol | Myricetin | ND | 0.992 ± 0.029 c | ND | 3.851 ± 0.049 b | ND | 8.38 ± 0.737 a | ND | 0.672 ± 0.005 c |
| Quercetin | ND | 3.084 ± 0.045 c | 1.798 ± 0.091 b | 8.055 ± 0.129 b | ND | 24.798 ± 1.168 a | 8.356 ± 0.977 a | 3.729 ± 0.109 c | |
| Kaempferol | 1.396 ± 0.485 b | 3.499 ± 0.044 b | 1.407 ± 0.015 a | 2.602 ± 0.028 c | ND | 6.991 ± 0.179 a | 1.404 ± 0.059 a | 2.037 ± 0.002 c | |
| Rutin | 1.086 ± 0.267 c | 4.666 ± 0.726 b | 1.655 ± 0.096 b | 3.769 ± 0.045 c | 1.288 ± 0.078 c | 5.241 ± 0.884 a | 3.287 ± 0.504 a | 3.22 ± 0.303 c | |
| Total | 42.742 ± 0.986 a | 28.054 ± 0.307 d | 11.169 ± 0.064 c | 31.775 ± 1.016 c | 2.707 ± 0.044 d | 103.735 ± 1.017 a | 19.756 ± 1.107 b | 36.450 ± 1.152 b | |
| Total flavone | 70.796 ± 0.898 b | 42.944 ± 0.906 d | 106.442 ± 1.06 a | 56.206 ± 0.336 c | |||||
| Total | 62.192 ± 2.632 a | 217.06 ± 1.614 c | 17.858 ± 0.161 c | 344.319 ± 2.13 b | 11.747 ± 0.999 d | 706.3 ± 2.145 a | 25.466 ± 1.215 b | 127.346 ± 2.388 d | |
| Total phenol + total flavonoids | 279.252 ± 2.426 c | 362.178 ± 2.208 b | 718.047 ± 3.021 a | 152.811 ± 1.103 d | |||||
ND, not detected. Lower-case letters in the table indicate significant differences among different colors of barley in free or bound fraction (p < 0.05).