Table 2.
Families of phytochemical detected by untargeted metabolomics.
| Family | Spectral library match | mz/RT (+/-) | CC | WR1 | WR2 |
|---|---|---|---|---|---|
| acyl glycine | Hippuric acid | 180.0596/2.1 (-) | 3.31E+05 ± 1.24E+04 | 2.27E+05 ± 2.45E+04 | 2.06E+05 ± 4.25E+03 |
| amine | Tyramine | 138.0913/0.9 (+) | 3.37E+06 ± 1.35E+05 | 5.53E+04 ± 3.27E+03 | u.d |
| benzopyrone | Coumarin | 147.0439/10.6 (+) | 2.15E+04 ± 3.32E+03 | 5.58E+05 ± 2.78E+04 | 5.12E+05 ± 2.93E+04 |
| cinnamate ester | Neochlorogenic acid | 353.0877/6.7 (-) | 1.08E+07 ± 2.04E+06 | 1.46E+06 ± 3.03E+05 | 3.58E+05 ± 7.17E+04 |
| dihyroflavonol | Dihydrokaempferol | 287.0563/9.7 (-) | 8.64E+04 ± 4.66E+03 | 1.19E+05 ± 4.98E+03 | 1.90E+04 ± 1.52E+03 |
| diterpenoid | Gibberellic acid | 345.1345/8.4 (-) | u.d | u.d | 1.30E+06 ± 9.65E+05 |
| flavan 3-ol | Catechin | 289.0715/6.7 (-) | 3.99E+05 ± 5.85E+04 | 1.85E+04 ± 3.20E+03 | 4.03E+05 ± 1.34E+04 |
| flavan 3-ols | Epicatechin | 289.0715/7.0 (-) | 1.36E+05 ± 1.57E+04 | u.d | u.d |
| flavanone | Eriodictyol | 287.0561/6.8 (-) | 9.14E+04 ± 7.19E+03 | u.d | 2.01E+05 ± 4.65E+03 |
| flavone | 6,2’-Dihydroxyflavanone | 257.0675/8.3 (-) | u.d | 2.16E+06 ± 1.15E+05 | 9.32E+03 ± 9.54E+02 |
| flavone | Afzelin | 431.0978/9.7 (-) | u.d | 6.86E+04 ± 7.93E+03 | 4.07E+04 ± 5.71E+03 |
| flavone | Apigenin | 269.0458/11.9 (-) | u.d | u.d | 2.69E+05 ± 1.64E+04 |
| flavone | Apigenin 7-glucoside | 431.0976/8.8 (-) | 2.21E+04 ± 3.10E+03 | 6.12E+04 ± 4.01E+03 | 5.06E+03 ± 1.76E+03 |
| flavone | Luteolin | 287.0550/8.4 (+) | 6.95E+04 ± 9.28E+03 | 7.96E+05 ± 4.60E+04 | 2.63E+06 ± 1.19E+05 |
| flavone | Naringenin | 273.0755/9.7 (+) | 9.78E+04 ± 4.34E+03 | 4.01E+04 ± 1.16E+04 | u.d |
| flavone C-glycoside | Kaempferol-3-O-rutinoside | 593.1525/8.0 (-) | 4.36E+04 ± 6.57E+03 | 3.33E+06 ± 1.38E+05 | 4.34E+06 ± 2.98E+05 |
| flavone C-glycoside | Kaempferol-7-O-Neohesperidoside | 595.1673/8.0 (+) | 3.70E+04 ± 5.42E+03 | 1.98E+06 ± 6.99E+04 | 3.19E+06 ± 2.32E+05 |
| flavone C-glycoside | Quercetin 3-glucoside | 463.0881/8.0 (-) | 4.48E+06 ± 3.81E+05 | 8.91E+04 ± 1.24E+04 | 1.41E+05 ± 1.16E+04 |
| flavone C-glycoside | Rutin | 611.1617/7.7 (+) | 1.94E+06 ± 1.45E+05 | 5.90E+04 ± 5.04E+03 | 1.54E+04 ± 1.53E+03 |
| flavone C-glycoside | Vicenin 2 | 595.1518/6.5 (-) | 1.64E+06 ± 1.33E+05 | u.d | u.d |
| flavonoid | Tiliroside | 593.1311/10.4 (-) | u.d | u.d | 6.30E+05 ± 4.19E+04 |
| flavonoid glycoside | Isoquercetrin | 465.1034/8.0 (+) | 2.31E+06 ± 1.65E+05 | u.d | u.d |
| flavonoid glycoside | Nepetin 7-glucoside | 479.1190/9.3 (+) | u.d | u.d | 2.77E+05 ± 1.64E+04 |
| flavonol | Kaempferol | 285.0401/12.3 (+) | 2.72E+04 ± 3.74E+03 | 1.64E+05 ± 1.01E+04 | 1.28E+05 ± 5.24E+03 |
| flavonol | Quercitrin | 447.0947/8.4 (-) | 1.40E+05 ± 4.23E+04 | 1.95E+06 ± 8.08E+04 | 5.65E+06 ± 2.06E+05 |
| flavonolignan | 2,3-Dehydrosilybin | 479.0823/8.0 (-) | 1.96E+05 ± 2.74E+04 | u.d | u.d |
| glycosyloxyflavone | Robinin | 739.1904/10.2 (-) | u.d | 1.18E+06 ± 8.03E+04 | 5.27E+03 ± 1.06E+03 |
| hydroquinone | 3,4-Dihydroxybenzoic acid | 153.0196/4.9 (-) | 1.05E+06 ± 1.21E+05 | 2.95E+06 ± 2.65E+05 | 1.91E+05 ± 7.31E+03 |
| indole alkaloid | Theobromine | 181.0715/4.4 (+) | 5.73E+06 ± 2.75E+05 | u.d | u.d |
| indole alkaloid | Theophylline | 181.0715/5.1 (+) | 5.16E+05 ± 2.53E+04 | u.d | u.d |
| indole alkaloid | Yohimbine/Rauwolscine | 355.2026/7.1 (+) | 1.01E+04 ± 3.91E+03 | 1.46E+06 ± 6.27E+04 | 4.89E+04 ± 1.93E+04 |
| indolizine | Isorhyncophylline | 385.2123/7.0 (+) | 6.02E+04 ± 1.73E+04 | 3.06E+06 ± 1.15E+05 | 9.46E+04 ± 3.38E+03 |
| methylxanthine alkaloid | Caffeine | 195.0891/6.1 (+) | 5.26E+08 ± 1.56E+07 | 1.50E+05 ± 4.41E+04 | 1.69E+05 ± 1.89E+04 |
| monohydroxybenzoic acid | Gentisic acid | 153.0191/6.0 (-) | 1.53E+05 ± 1.10E+04 | 1.14E+05 ± 6.57E+03 | 1.03E+05 ± 3.87E+04 |
| monohydroxybenzoic acid | Vanillic acid | 167.0344/8.2 (-) | 7.58E+04 ± 6.60E+03 | 2.80E+04 ± 2.22E+03 | 4.14E+04 ± 4.94E+03 |
| monolignol | Coumaric acid* | 163.0403/6.1 (-) | 4.51E+06 ± 5.51E+05 | 1.26E+05 ± 3.99E+03 | 8.31E+04 ± 2.90E+03 |
| monolignol | Scopoletin | 191.0352/8.4 (-) | 4.12E+04 ± 4.89E+03 | 2.81E+05 ± 1.29E+04 | 2.30E+04 ± 1.40E+03 |
| monolignol | trans-3-Coumaric acid* | 147.0440/7.8 (+) | 1.07E+06 ± 1.77E+05 | u.d | u.d |
| oxopurine alkaloid | 1,3,7-Trimethyluric acid | 209.0684/5.3 (-) | 5.81E+05 ± 7.30E+04 | 3.13E+03 ± 7.31E+02 | 2.72E+03 ± 2.84E+02 |
| oxylipin | Methyl salicylate | 153.0544/7.2 (+) | 5.84E+05 ± 2.62E+04 | 5.59E+04 ± 1.96E+04 | 1.01E+04 ± 9.88E+02 |
| phenolic aldehyde | 2,5-Dihydroxybenzaldehyde | 137.0247/6.2 (-) | 4.28E+06 ± 1.86E+05 | 5.52E+05 ± 3.22E+04 | 1.01E+05 ± 1.23E+04 |
| phenylpropanoid | Benzoic acid | 121.0309/7.4 (-) | 1.87E+06 ± 8.04E+04 | 5.18E+06 ± 2.20E+05 | 5.11E+05 ± 2.90E+04 |
| phenylpropanoid | Esculetin | 177.0198/6.6 (-) | 1.20E+06 ± 4.69E+05 | 1.31E+05 ± 1.72E+04 | 7.18E+04 ± 5.87E+03 |
| phenylpropanoid | Esculin | 339.0719/6.4 (-) | 3.49E+04 ± 1.28E+04 | 9.44E+04 ± 2.03E+04 | 5.19E+04 ± 3.85E+03 |
| phenylpropanoid | p-Methoxycinnamic acid | 207.1011/8.1 (+) | 7.30E+04 ± 6.47E+03 | 2.94E+04 ± 1.03E+04 | u.d |
| phenylpropanoid | trans-Cinnamic acid | 181.0861/10.7 (+) | u.d | 6.00E+06 ± 3.18E+05 | u.d |
| polyphenol | Bisdemethoxycurcumin | 309.0964/8.9 (+) | u.d | 5.08E+05 ± 3.52E+04 | 1.08E+04 ± 1.64E+03 |
| polyphenol | Caffeic acid | 179.0349/6.7 (-) | 4.58E+05 ± 2.24E+04 | 2.08E+05 ± 1.01E+04 | 1.25E+05 ± 1.69E+04 |
| pyridine alkaloid | Trigonelline | 275.1030/1.0 (+) | 2.77E+07 ± 8.40E+05 | 6.01E+04 ± 9.90E+03 | 7.92E+03 ± 1.06E+03 |
| sesquiterpene | Abscisic acid | 263.1286/10.7 (-) | 7.83E+04 ± 4.48E+03 | 2.96E+04 ± 8.94E+02 | 1.43E+04 ± 5.80E+02 |
| trihydroxyanthraquinone | Chrysophanol | 255.0649/17.6 (+) | u.d | u.d | 1.66E+05 ± 1.28E+04 |
| trihydroxybenzoic acid | Gallic acid | 169.0140/3.5 (-) | 2.23E+05 ± 1.88E+04 | 4.58E+04 ± 9.22E+03 | u.d |
| triterpene | Sumaresinolic acid | 473.3626/11.9 (+) | u.d | u.d | 4.91E+05 ± 4.77E+04 |
| triterpenoid | Madecassic acid | 503.3371/15.2 (-) | u.d | 1.42E+05 ± 2.03E+04 | 1.39E+06 ± 2.18E+05 |
| triterpenoid | Maslinic acid | 471.3469/19.8 (+) | 5.32E+04 ± 9.97E+03 | 4.85E+05 ± 4.70E+04 | 8.16E+05 ± 4.40E+04 |
| triterpenoid | Soyasaponin I | 941.4949/15.3 (-) | u.d | 1.01E+05 ± 1.39E+04 | u.d |
| xanthone C-glycoside | Neomangiferin | 583.1305/5.3 (-) | 4.15E+05 ± 3.03E+04 | u.d | u.d |
The mass to charge ratio value represents the [M+H]+ and [M-H]- for the positive and negative modes, respectively, except compounds marked by an asterisk (*) which denotes a loss of water in the source. The areas of secondary metabolites extracted from leaves of commercial coffee (CC) and two wild Rubiaceae species (WR1 and WR2) ± standard deviation (n = 5 pseudoreplicates) are presented. When metabolites were detected in both polarities, only the one with the highest area was reported. Areas labeled as u.d. were under the limit of detection.
For each compound identified using NIST and homemade spectral libraries with > 70% probability, the mass to charge ratio, retention time in min (mz/RT), and mode of detection (positive +, or negative - polarity) are specified.