Table 4.
Interaction analysis of mutual mint infusions and mint extracts/rosmarinic acid combinations in DCFH-DA assays: IC50, CI, and DRI values of equal mass concentration infusions combinations at 50% inhibition dose level.
| Infusions Combination a | IC50 (μg/mL) b | r | CI c | SDA d | Combined Effect | DRI e | |
|---|---|---|---|---|---|---|---|
| DCFH-DA | MPP:RA | 0.64 (9.21:0.37) |
0.97 (0.99:0.97) |
0.89 | ±0.04 | slight synergism | 28.74:1.17 |
| ML:RA | 1.81 (13.34: 0.37) |
0.95 (0.99:0.97) |
2.49 | ±0.10 | antagonism | 14.77:0.41 | |
| MVS:RA | 1.42 (18.34:0.37) |
0.96 (0.98:0.97) |
1.94 | ±0.08 | antagonism | 25.79:0.53 |
a MPP—Mentha × piperita cv. ‘Perpeta’; ML—Mentha longifolia; MVS—Mentha × villosa cv. ‘Snežná’; RA—rosmarinic acid. b Median inhibitory activities IC50 (μg/mL) of the equal mass concentration infusions combinations and in bracket their single infusion/compound IC50 level. c CI—combination index, a quantitative measure based on the mass-action law of the degree of drug interaction in terms of synergism (CI < 1) and antagonism (CI > 1) for a given endpoint of the effect measurement. The combined effect is evaluated according to Chou (2006). d SDA-sequential deletion analysis, iterative sequential deletion of one dose (or concentration) of a drug at a time for repetitive CI calculations. e DRI represents the order of magnitude (fold) of dose reduction that is allowed in combination for a given degree of effect as compared with the dose of each drug alone.