Table 2. Tentative Identifications and Comparison of the Discriminant Metabolites in TFDG and EGCG Treated Samples after 48 h of Fermentation.
| TFDG
vs blank |
EGCG
vs blank |
TFDG
vs EGCG |
|||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ID | RT (min) | tentative identification | formula | m/za | Δ m/z (ppm)b | MS2 fragments | VIP score | Fc | pd | Fc | pd | Fc | pd |
| Negative ionization mode | |||||||||||||
| 1 | 7.69 | 5-(3′,4′-dihydroxyphenyl)valeric acid | C11H14O4 | 209.08130 | 2.98 | 123.08011; 81.03308; 87.92377; 147.07928; 149.45479 | 1.98 | 0.03 | 0.89 | 3.66 | 0.00 | –3.58 | 0.00 |
| 2 | 6.55 | 5-(3′,4′-dihydroxyphenyl) -γ-valerolactone | C11H12O4 | 207.06569 | 2.86 | 81.03300; 122.03589; 75.00153; 163.07542 | 1.98 | 0.14 | 0.31 | 4.15 | 0.00 | –3.97 | 0.04 |
| 3 | 5.55 | 5-(3′,4′,5′-trihydroxyphenyl)valeric acid | C11H14O5 | 225.07640 | 1.96 | 81.03300; 123.04277; | 1.97 | 1.36 | 0.41 | 5.21 | 0.00 | –3.83 | 0.00 |
| 4 | 5.54 | 5-(3′,5′-dihydroxyphenyl) -γ-valerolactone | C11H12O4 | 207.06569 | 2.86 | 75.00152; 87.92372; 122.03590; 118.99174 | 1.97 | –0.06 | 0.61 | 4.73 | 0.00 | –4.72 | 0.07 |
| 5 | 5.69 | unknown | 199.06039 | n.d. | 1.72 | 0.27 | 0.34 | 2.87 | 0.03 | –1.90 | 0.04 | ||
| 6 | 9.10 | theanaphthoquinone | C28H22O11 | 533.10870 | 0.43 | 349.07144; 125.02302; 137.02310; 165.01793 | 1.62 | 4.83 | 0.00 | –0.06 | 0.66 | 5.03 | 0.00 |
| 7 | 8.27 | unknown | 243.02988 | n.d. | 1.56 | 2.70 | 0.01 | –0.10 | 0.71 | 2.72 | 0.01 | ||
| Positive ionization mode | |||||||||||||
| 8 | 6.55 | 5-(3′,4′-dihydroxyphenyl) -γ-valerolactone | C11H12O4 | 209.08096 | –0.56 | 123.04430; 68.99796; 149.05981; 84.96044; 91.05495 | 2.10 | 0.10 | 0.05 | 3.67 | 0.00 | –3.55 | 0.03 |
| 9 | 5.54 | 5-(3′,4′,5′-trihydroxyphenyl)valeric acid | C11H14O5 | 227.09152 | –0.52 | n.d. | 2.06 | 0.09 | 0.17 | 4.84 | 0.00 | –4.51 | 0.03 |
| 10 | 5.55 | 5-(3′,5′-dihydroxyphenyl) -γ-valerolactone | C11H12O4 | 209.08101 | –0.80 | 68.99792; 123.04436; 121.06515; 149.05972; 81.07054 | 2.04 | 0.06 | 0.22 | 5.05 | 0.00 | –4.70 | 0.03 |
| 11 | 9.10 | theanaphthoquinone | C28H22O11 | 535.12311 | 0.71 | n.d. | 1.64 | 2.89 | 0.00 | 0.02 | 0.64 | 2.93 | 0.00 |
| 12 | 8.72 | unknown | 169.08500 | n.d. | 1.50 | –0.73 | 0.02 | 0.68 | 0.14 | –1.74 | 0.19 | ||
a
Measured [M – H]− in negative ionization mode or measured [M + H]+ in positive ionization mode.
b
Difference between calculated and experimental m/z.
c
log2 fold change of average peak areas (n = 4).
d
p value in Student’s t-test (n = 4); n.d., not detected.