Table 4.
Maximum emission wavelength (Emax) of chemiluminescence from flavonoids in the presence of hydrogen peroxide, acetaldehyde, and horseradish peroxidase
| Compound | Substituent position | Emax (nm) | Chemiluminescence intensity (×104 counts/500 sec) | |
|---|---|---|---|---|
| Catechins | (R1) | (R2) | 990 | |
| Epigallocatechin-3-gallete | OH | Gaa | 630 | 950 |
| Epigallocatechin | OH | 630 | 6 | |
| Epicatechin | H | 630 | ||
| Theaflavins | (R3) | (R4) | ||
| Theaflavin digallate | Ga | Ga | 690 | 400 |
| Theaflavin | H | H | 690 | 24 |
| Anthocyanins | (R5) | (R6) | ||
| Delphinidin | OH | H | 675 | 350 |
| Cyanidin | H | H | 675 | 95 |
| Cyanidin-3-glucoside | H | Glucb | 675 | 156 |
| Other phenolics | ||||
| Gallic acid | 670 | 57 | ||
| Caffeic acid | 670 | 6 | ||
| Curcumin | 640 | 43 | ||
| α-Tocopherol | No chemiluminescence | |||
| (Ascorbic acid) | No chemiluminescence | |||
aGalloyl.
bGlucose.
The chemical structures are given below, and R1–R6 are substituted, as given above.
Adapted with permission from Ref. 86. Copyright 1998 Taylor & Francis.