Background
Methods
Plant material
Preparation of peel extract
Antibacterial property
Microdilution antibacterial assay
Antioxidant property
Radical-scavenging ability
Ferrous ion chelating (FIC) assay
Ferric ion reducing antioxidant power (FRAP) assay
Tyrosinase inhibition property
Phenolic content determination
Total phenolic content (TPC)
Total flavonoid content (TFC)
Rhodanine assay for gallotannin content (GTC)
Total anthocyanin content (TAC)
HPLC-ESI/MSn analysis of phenolic composition
Statistical analysis
Results and discussion
Antibacterial activity
Minimum inhibitory concentration (MIC; mg/ml) | ||||||
---|---|---|---|---|---|---|
Cultivar | Extract | B.s | E.c | K.p | S.a | TAI |
Arakta | MeOH | 0.39b
| 0.78b
| 0.20a
| 0.39b
| 6.00b
|
Aqueous | >12.50 | >12.50 | >12.50 | >12.50 | <1.00 | |
Bhagwa | MeOH | 0.39b
| 0.78b
| 0.20a
| 0.78c
| 5.70a
|
Aqueous | >12.50 | >12.50 | >12.50 | >12.50 | <1.00 | |
Ganesh | MeOH | 0.39b
| 0.39a
| 0.20a
| 0.78c
| 6.00b
|
Aqueous | >12.50 | >12.50 | >12.50 | >12.50 | <1.00 | |
Herskawitz | MeOH | 0.20a
| 0.39a
| 0.20a
| 0.78c
| 6.25c
|
Aqueous | >12.50 | >12.50 | >12.50 | >12.50 | <1.00 | |
Molla de Elche | MeOH | 0.39b
| 0.78b
| 0.39b
| 0.26a
| 5.92ab
|
Aqueous | >12.50 | >12.50 | >12.50 | >12.50 | <1.00 | |
Ruby | MeOH | 0.39b
| 0.39a
| 0.39b
| 0.39b
| 6.00b
|
Aqueous | >12.50 | >12.50 | >12.50 | >12.50 | <1.00 | |
Wonderful | MeOH | 0.39b
| 0.59ab
| 0.33b
| 0.39b
| 5.99b
|
Aqueous | >12.50 | >12.50 | >12.50 | >12.50 | <1.00 | |
Streptomycin (μg/ml) | 3.13 | 3.13 | 2.60 | 5.21 |
Antioxidant activity
DPPH (%) | FIC (%) | FRAP (abs. at 593 nm) | |||||||
---|---|---|---|---|---|---|---|---|---|
Cultivar | 1000 μg/ml | 100 μg/ml | 10 μg/ml | 1000 μg/ml | 100 μg/ml | 10 μg/ml | 1000 μg/ml | 100 μg/ml | 10 μg/ml |
Arakta | 83.54±0.31d
| 13.35±0.98ab
| 5.55±0.06c
| 79.44±0.21a
| 49.94±0.89a
| 37.32±1.82b
| 1.19±0.03ns
| 0.52±0.02b
| 0.11±0.00c
|
Bhagwa | 73.02±0.26ab
| 12.34±0.73ab
| 1.37±0.34a
| 84.96±1.43bc
| 65.54±1.09c
| 18.83±0.22a
| 1.03±0.28 | 0.38±0.00ab
| 0.04±0.01a
|
Ganesh | 83.56±0.05d
| 16.70±0.83bc
| 2.42±0.99ab
| 82.98±0.18b
| 65.82±0.51c
| 15.80±0.52a
| 1.47±0.04 | 0.73±0.12c
| 0.08±0.01bc
|
Herskawitz | 78.06±0.71c
| 15.18±0.97abc
| 2.71±0.77ab
| 87.82±0.57de
| 69.97±0.25d
| 34.32±2.45b
| 1.29±0.04 | 0.34±0.01ab
| 0.08±0.02bc
|
Molla de Elche | 71.65±0.08a
| 10.59±0.18a
| 1.61±0.08a
| 86.59±0.90cd
| 70.57±0.43d
| 47.24±1.34c
| 1.47±0.11 | 0.33±0.05a
| 0.03±0.00a
|
Ruby | 83.34±0.51d
| 19.67±2.24c
| 4.10±2.24bc
| 83.58±0.62b
| 53.39±1.29b
| 47.25±0.66c
| 1.18±0.02 | 0.38±0.00ab
| 0.08±0.01bc
|
Wonderful | 74.19±1.05b
| 12.22±3.13ab
| 3.01±0.47ab
| 89.67±0.72e
| 71.02±0.38d
| 49.65±1.26c
| 1.32±0.16 | 0.33±0.01a
| 0.06±0.00ab
|
Ascorbic acid | 67.02±0.06 | 62.15±0.98 | |||||||
Trolox | 0.82±0.03 |
Tyrosinase inhibition activity
Cultivar | IC50 Monophenolase (μg/ml) | IC50 Diphenolase (μg/ml) |
---|---|---|
Arakta | 11.03±0.08c
| 15.88±0.10a
|
Bhagwa | 3.66±0.11a
| 21.16±0.09a
|
Ganesh | 25.38±0.06f
| 40.93±0.12b
|
Herskawitz | 7.56±0.08b
| 59.03±0.07c
|
Molla de Elche | 25.56±0.06f
| 27.11±0.09ab
|
Ruby | 20.33±0.07d
| 114.9±0.08e
|
Wonderful | 23.67±0.06e
| 27.26±0.07ab
|
Arbutin | 34.66±0.05g
| 98.66±0.12d
|
Phenolic compounds analysis
Total phenolics, flavonoid, gallotannin and anthocyanin
Cultivar | Total phenolics | Total flavonoid | Total gallotannin | Total anthocyanin |
---|---|---|---|---|
mg GAE/ g DM | mg CAE /g DM | μg GAE/ g DM | μg C3gE /g DM | |
Arakta | 187.4±6.44ab
| 103.0±1.86a
| 783.6±65.11d
| 289.7±1.63d
|
Bhagwa | 224.1±6.86c
| 112.6±1.51b
| 697.7±42.92cd
| 312.6±1.25e
|
Ganesh | 295.5±23.91d
| 121.1±3.12c
| 777.2±34.28d
| 65.1±1.00a
|
Herskawitz | 198.1±9.22abc
| 101.0±1.02a
| 530.1±33.86b
| 195.9±2.25c
|
Molla de Elche | 179.3±4.60a
| 99.5±2.94a
| 560.3±62.08bc
| 58.5±1.27a
|
Ruby | 218.2±4.53bc
| 126.0±0.57c
| 326.0±35.28a
| 111.7±3.51b
|
Wonderful | 189.1±3.79ab
| 97.8±2.10a
| 466.3±69.4ab
| 322.2±11.90f
|