Table 2.
Protein content, DPPH, NO, and O2 •−-antiradical powers, permanganate reducing antioxidant capacity, ferric reducing antioxidant power, and lipid peroxidation in oak twigs, leaves, and acorns of two Serbian oak species Quercus robur L. and Quercus petraea L.
Plant organ | Locality | Prot. (mg/g) | DPPH-ARP ((1/IC50)·100) | NO-ARP ((1/IC50)·100) | O2 •−-ARP ((1/IC50)·100) | PRAC (A50) | FRAP (FRAP units) | LP (nmol/mg prot.) |
---|---|---|---|---|---|---|---|---|
Twigs | Q. robur | 52.45a | 5.874a | 0.358a | 2.174a | 0.016a | 141.54a | 67.18a |
Q. petraea | 103.9b | 4.039b | 0.241b | 3.571b | 0.010a | 178.5a | 28.08b | |
Leaves | Q. robur | 427.0c | 7.628c | 0.531c | 3.448b | 0.304b | 873.8b | 11.01c |
Q. petraea | 159.6d | 8.779d | 0.400d | 4.785c | 0.235c | 1252.3c | 11.96c | |
Acorns | Q. robur | 352.1e | 9.066d | 0.188e | 5.359d | 0.411d | 370.0d | 3.282d |
Q. petraea | 95.60b | 6.734e | 0.202e | 4.098e | 0.543e | 614.6e | 2.023d |
*Values with the same letter, in each colon, are not significantly different according to Duncan test (P < 0.05).
**Prot.: proteins; ARP: antiradical power; ARP = ((1/IC50)·100); IC50: the concentration of an sample at which 50% inhibition of free radical activity is observed; PRAC: permanganate reducing antioxidant capacity; A50: antioxidant activity reflected in time until the sample induces a decrease of the oxidizing agent (potassium permanganate) up to one half, compared against a standard (ascorbic acid); A50 = mmol ascorbate eq./g; FRAP: ferric reducing antioxidant power; 1 FRAP unit = 100 μmol/dm3 Fe2+; LP: lipid peroxidation.