Table 1.
Antioxidant activity of flavonoids and their combinations evaluated by DPPH assay
| S.No | Combination of phytochemicals in different ratio | EC50 (μM) ± STDEV | Difference in DPPH antioxidant activity (%) | P-value | |
|---|---|---|---|---|---|
| P1 | P2 | ||||
| 1 | Rutin hydrate | Quercetin dihydrate | |||
| 1 | 0 | 323.65 ± 27.26 | |||
| 1 | 1 | 305.77 ± 19.26 | − 0.67 ± 2.38 | a−, b− | |
| 2 | 1 | 315.87 ± 3.49 | − 4.17 ± 4.59 | a−, b$ | |
| 3 | 1 | 317.49 ± 7.00 | − 4.71 ± 5.21 | a−, b# | |
| 0 | 1 | 283.65 ± 4.82 | |||
| 1 | 2 | 312.22 ± 7.23 | − 2.91 ± 2.91 | a−, b# | |
| 1 | 3 | 295.29 ± 15.31 | 2.63 ± 6.31 | a−, b− | |
| 2 | Rutin hydrate | Hydroquinone | |||
| 1 | 0 | 310.78 ± 8.60 | |||
| 1 | 1 | 414.94 ± 33.22 | 0.21 ± 6.31 | a#, b# | |
| 2 | 1 | 383.55 ± 21.51 | 7.66 ± 5.76 | a#, b$ | |
| 3 | 1 | 383.12 ± 38.25 | 7.12 ± 7.50 | a*, b# | |
| 0 | 1 | 520.34 ± 13.34 | |||
| 1 | 2 | 444.33 ± 40.72 | − 6.86 ± 8.22 | a#, b* | |
| 1 | 3 | 494.46 ± 74.52 | − 18.80 ± 15.77 | a*, b− | |
| 3 | Rutin hydrate | Kaempferol | |||
| 1 | 0 | 310.18 ± 2.27 | |||
| 1 | 1 | 339.70 ± 16.84 | 1.49 ± 3.83 | a*, b* | |
| 2 | 1 | 324.83 ± 14.83 | 5.77 ± 4.38 | a−, b# | |
| 3 | 1 | 325.38 ± 17.59 | 5.62 ± 4.82 | a−, b# | |
| 0 | 1 | 379.31 ± 9.27 | |||
| 1 | 2 | 344.90 ± 12.83 | − 0.03 ± 3.25 | a#, b# | |
| 1 | 3 | 347.50 ± 13.73 | − 0.77 ± 2.86 | a#, b* | |
| 4 | Rutin hydrate | Resveratrol | |||
| 1 | 0 | 297.21 ± 5.74 | |||
| 1 | 1 | 409.38 ± 20.01 | 30.56 ± 1.72 | a$, b$ | |
| 2 | 1 | 364.15 ± 25.42 | 38.27 ± 1.82 | a#, b$ | |
| 3 | 1 | 348.28 ± 23.47 | 40.92 ± 3.10 | a*, b$ | |
| 0 | 1 | 881.80 ± 52.77 | |||
| 1 | 2 | 489.71 ± 1.26 | 16.84 ± 3.47 | a$, b$ | |
| 1 | 3 | 550.32 ± 19.55 | 6.46 ± 7.03 | a$, b$ | |
| 5 | Quercetin dihydrate | Hydroquinone | |||
| 1 | 0 | 269.12 ± 2.78 | |||
| 1 | 1 | 347.81 ± 7.51 | 9.56 ± 1.33 | a$, b$ | |
| 2 | 1 | 320.96 ± 14.83 | 16.43 ± 6.34 | a#, b$ | |
| 3 | 1 | 316.32 ± 20.88 | 17.82 ± 3.16 | a#, b$ | |
| 0 | 1 | 500.19 ± 25.53 | |||
| 1 | 2 | 388.27 ± 12.80 | − 1.10 ± 0.62 | a$, b# | |
| 1 | 3 | 387.49 ± 22.53 | − 0.80 ± 6.86 | a$, b# | |
| 6 | Quercetin dihydrate | Kaempferol | |||
| 1 | 0 | 273 ± 7.98 | |||
| 1 | 1 | 310.60 ± 13.35 | 10.60 ± 3.00 | a#, b$ | |
| 2 | 1 | 286.94 ± 15.28 | 17.41 ± 3.74 | a−, b$ | |
| 3 | 1 | 299.36 ± 10.70 | 13.79 ± 4.08 | a*, b$ | |
| 0 | 1 | 421.32 ± 11.52 | |||
| 1 | 2 | 339.37 ± 26.28 | 2.39 ± 5.50 | a#, b# | |
| 1 | 3 | 358.08 ± 11.89 | − 3.05 ± 1.34 | a$, b# | |
| 7 | Quercetin dihydrate | Resveratrol | |||
| 1 | 0 | 267.38 ± 1.49 | |||
| 1 | 1 | 402.71 ± 25.80 | 8.00 ± 2.45 | a$, b$ | |
| 2 | 1 | 350.46 ± 23.56 | 19.92 ± 3.34 | a#, b$ | |
| 3 | 1 | 325.95 ± 17.76 | 25.50 ± 2.35 | a#, b$ | |
| 0 | 1 | 607.63 ± 37.24 | |||
| 1 | 2 | 461.57 ± 40.83 | − 5.36 ± 5.14 | a$, b# | |
| 1 | 3 | 485.81 ± 37.39 | − 10.93 ± 4.07 | a$, b# | |
| 8 | Hydroquinone | Kaempferol | |||
| 1 | 0 | 435.18 ± 4.22 | |||
| 1 | 1 | 375.71 ± 13.92 | 12.82 ± 2.87 | a#, b# | |
| 2 | 1 | 394.56 ± 26.79 | 8.45 ± 5.86 | a−, b− | |
| 3 | 1 | 407.99 ± 13.12 | 5.33 ± 2.69 | a*, b− | |
| 0 | 1 | 426.63 ± 3.59 | |||
| 1 | 2 | 384.08 ± 14.40 | 10.87 ± 2.97 | a#, b# | |
| 1 | 3 | 391.06 ± 4.91 | 9.25 ± 0.99 | a$, b$ | |
| 9 | Hydroquinone | Resveratrol | |||
| 1 | 0 | 381.06 ± 16.21 | |||
| 1 | 1 | 430.31 ± 25.90 | 11.24 ± 3.21 | a*, b$ | |
| 2 | 1 | 405.37 ± 51.99 | 16.49 ± 8.41 | a−, b# | |
| 3 | 1 | 418.34 ± 36.26 | 13.74 ± 5.53 | a−, b# | |
| 0 | 1 | 588.25 ± 20.43 | |||
| 1 | 2 | 457.01 ± 43.97 | 5.77 ± 7.05 | a*, b# | |
| 1 | 3 | 488.84 ± 50.18 | − 0.74 ± 7.45 | a*, b* | |
| 10 | Kaempferol | Resveratrol | |||
| 1 | 0 | 439.63 ± 3.36 | |||
| 1 | 1 | 517.21 ± 32.37 | − 0.4 ± 4.10 | a#, b− | |
| 2 | 1 | 522.21 ± 25.53 | − 1.47 ± 5.82 | a#, b− | |
| 3 | 1 | 511.68 ± 27.45 | 0.52 ± 7.22 | a#, b− | |
| 0 | 1 | 591.04 ± 59.66 | |||
| 1 | 2 | 545.28 ± 40.40 | − 5.74 ± 2.08 | a#, b− | |
| 1 | 3 | 560.33 ± 45.83 | − 8.63 ± 2.75 | a#, b− | |
Variables a and b indicate statistical comparison of EC50 values of the phytochemical combinations with phytochemical 1 (1:0) and phytochemical 2 (0:1), respectively
The superscripts *, #, and $ are for P-value ≤ 0.05, 0.01, and 0.001. ‘ − ’ represents non-significant values