Investigation of the hemostatic effects of freeze-dried extracts of selected Kenyan plants

Abstract. Makunyi EG, Bukachi F, Waweru P. 2019. Investigation of the hemostatic effects of freeze-dried extracts of selected Kenyan plants. Biofarmasi J Nat Prod Biochem 17: 39-46. This study aims to investigate the effect and mechanism of action of freeze-dried extracts of Tridax procumbens, Terminalia brownii, Euphorbia tirucalli, and Asphillia africana on hemostasis. Freeze-dried extract of the selected plants was prepared and dose determined for the study. Twelve male New Zealand white rabbits were randomly allocated to two groups (control and test). Blood was collected under standard procedures. Duke's method was used for the bleeding time while the capillary method was used for clotting time. ACL Elitepro machine was used to do prothrombin time and activated partial thromboplastin time. Thromboelastography was done for the most potent extracts. Data were analyzed using independent t-test and results were presented as mean± standard error of means. Differences were considered to be significant if P < 0.05. The results showed that the percentage yield of the extract was; Tridax procumbens (0.8%), Terminalia brownii (0.5%), Euphorbia tirucalli (0.2%) and Aspillia pluriseta (1.3%). Bleeding and clotting time: The bleeding time was reduced by freeze-dried leaf extract of Tridax procumbens (p = 0.0068) and by freeze-dried bark extract of Terminalia brownii (p=0.0068). Freeze-dried leaf extract of Asphillia africana increased the bleeding time (p=0.01). The clotting time was reduced by freeze-dried leaf extract of Tridax procumbens (p = 0.038), the freeze-dried bark extract of Terminalia brownii (p=0.043) and by freeze-dried stem extract of Euphorbia tirucalli (p=0.01). Prothrombin and activated partial thromboplastin time: The prothrombin time was reduced by freeze-dried leaf extract of Tridax procumbens (p = 0.004), the freeze-dried bark extract of Terminalia brownii (p<0.001) and Freeze-dried stem extract of Euphorbia tirucalli (p=0.001). Activated partial thromboplastin time was reduced by freeze-dried leaf extract of Tridax procumbens (p< 0.001), the freeze-dried bark extract of Terminalia brownii (p<0.001) and by freeze-dried stem extract of Euphorbia tirucalli (p<0.001). The results for thromboelastogrpahy showed that four parameters of thromboelastography were tested. Freeze-dried leaf extract of Tridax procumbens reduced the r time (p =0.04), k time (p=0.04) and maximum amplitude (p =0.026) but increased the alpha angle (p =0.01). The freeze-dried bark extract of Terminalia brownii did not have statistically significant differences in thromboelastography variables.