Abstract
Several medicinal plants are known to possess anticoagulant activity. This study proposed to evaluate the in vitro anticoagulant effect of methanol extracts of Citrullus colocynthis (fruits), Achillea fragrantissima (aerial parts) and Artemisia herba-alba (aerial parts) on normal human plasma. A total of 100 blood samples used in this study were taken from healthy volunteers at the Hematology laboratory of King Khalid Hospital, Al-Majmaah, Kingdom of Saudi Arabia from November 2018 to March 2019, using 3.2% sodium citrate tubes with a collection ratio of 9:1 blood to anticoagulant. PT, INR and PTT were used to assess the anticoagulant activity of these plants. The highest PT results were observed for 1000 mu g/mL methanol extract of C. colocynthis (33.7 +/- 3.4 s) followed by 1000 mu g/mL methanol extract of A. fragrantissima (28.2 +/- 2.6 s) and 1000 mu g/mL methanol extract of A. herba-alba (26.4 +/- 0.2 s). Moreover, the highest PTT values were observed for 250, 500 and 1000 mu g/mL A. fragrantissima (87.9 +/- 1.0, 97.9 +/- 5.1 and 112.5 +/- 1.1 s, respectively), 500 mu g/mL and 1000 mu g/mL C. colocynthis (65.1 +/- 1.0 and 106.4 +/- 0.4 s, respectively) and 1000 mu g/mL A. herba-alba (157.0 +/- 3.0 s). The anticoagulant effect of methanol extracts of A. herba-alba, A. fragrantissima, and C. colocynthis were evaluated using coagulation assays, in which prolonged clotting time of their methanol extracts was observed. These findings potentially justify the use of these plants in managing arterial and venous thrombotic disorders.