RESUMO
Objective:A strong antithrombotic protein component， named PvQ， was purified and enriched from total protein of <italic>Pheretima vulgaris</italic>，<italic> </italic>a<italic> </italic>traditional Chinese medicine. Moreover， we evaluated its fibrinolytic and anticoagulant activity， and expected to provide reference for the research on antithrombotic substances of Pheretima. Method:A rapid <italic>in</italic> <italic>vitro</italic> activity-oriented separation combined with the AKTA-Pure protein purification system conducted on <italic>P. vulgaris</italic>. Meanwhile， the fibrinolytic and anticoagulant activities of PvQ were measured by fibrin plate method and fibrinogen-thrombin time （Fibg-TT） method. And the <italic>in vitro</italic> thrombolysis assay was used for evaluating the lysis ability of PvQ to thrombus. Then the stability of PvQ was also analyzed for its anticoagulant activity at different pH and temperature. Result:The PvQ was successfully enriched and its activity was determined to have significant fibrinolytic and anticoagulant activities. And the result of <italic>in vitro</italic> thrombolysis assay revealed that PvQ could hydrolyze more than 80% of thrombus after 5 h of incubation at 37 ℃. In addition， the changes of temperature and pH had significant effects on antithrombotic activity， and this study showed that PvQ was rapidly inactivated at ≥60 ℃ or in acidic conditions （pH<7）. While， the activity of PvQ was unaffected or less affected at ≤50 ℃ and under alkaline conditions. Conclusion:A feasible preparation method of PvQ is established， and it can affect fibrin and fibrinogen at the same time， thus exerting a dual fibrinolytic effect and possessing significant fibrinolytic and anticoagulant activities. It provides a scientific interpretation for the treatment of thrombotic diseases by PvQ and a reference for the development of antithrombotic protein products of Pheretima.