Potent antiplatelet aggregation, anticoagulant and antioxidant activity of aerial Canna x generalis L.H Bailey & E.Z Bailey and its phytoconstituents

Abstract

This study evaluated for the first time the inhibitory effect on human platelet aggregation, blood coagulation, and the antioxidant activity of Canna x generalis fractions and its phytoconstituents. The antiplatelet effect was evaluated using the turbidimetric method to determine the percentage inhibition (%I), the area under aggregation curve (AUC) and the aggregation velocity (slope). Prothrombin time (PT), activated partial thromboplastin time (APTT) and thrombin time (TT) were measured to assess the inhibitory effect on blood coagulation. ABTS and DPPH assays were performed for evaluation of the antioxidant effect. Compounds structures were determined by NMR and MS spectroscopic methods. The ethyl acetate fraction exhibited the most potent antiplatelet (%I, 98.2 ± 1.7% at 4 mg/mL), anticoagulation (mean APTT, 42.97 s) and antioxidant activity (IC50, 58 ± 0.1 and 12.5 ± 2.0 μg/mL for DPPH and ABTS, respectively). Thirteen compounds were found for the first time from aerial CG: 16α-hydro‑ent-kauran-3β-ol-7,19-dioic acid, named cannagelic acid (a new ent‑kaurane diterpenoid) (1), 16α-hydro‑ent-kauran-17,19-dioic acid (2), ent‑kauran-15-en-17,19-dioic acid (3), 3-methoxybenzaldehyde (4), 2-methoxynaphtalene (5), 4-ketopinoresinol (6), p-coumaric acid (7), indole-3-carboxylic acid (8), procatechuic aldehyde (9), astragalin (10), isoquercitrin (11), corchoionol C (12) and rutin (13). Compounds 7, 9–11, 13 possess good antiplatelet, anticoagulant and antioxidant activity. This study demonstrated that compound 1 did not show any tested effects. Compounds 4 and 5 had a very weak antiplatelet effect. Compound 8 expressed the highest capacity to inhibit platelet aggregation for both ADP and collagen (%I = 70.2 ± 1.8 and 79.2 ± 1.4 at 0.4 mg/mL, respectively), followed by compound 6. Moreover, these two compounds at 0.4 mg/mL could prolong APTT compared to the negative control (p < 0.05). Compound 12 had weak antiplatelet activity, but its antioxidant effect was better than other tested compounds. In conclusion, CG would be a good natural resource of bioactive molecules or dietary supplements to prevent and/or treat cardiovascular and free radicals-associated diseases.