Neutralization of proteases from Bothrops snake venoms by the aqueous extract from Casearia sylvestris (Flacourtiaceae)

Aqueous extract from Casearia sylvestris leaves, a typical plant from Brazi lian open pastures, was able to neutralize the hemorrhagic activity caused by Bothrops asper, Bothrops jararacussu, Bothrops moojeni, Bothrops neuwied i and Bothrops pirajai venoms. It also neutralized two hemorrhagic metallop roteinases from Bothrops asper venom. Proteolytic activity on casein induce d by bothropic venoms and by isolated proteases, including Bn2 metalloprote inase from B. neuwiedi venom, was also inhibited by the C. sylvestris extra ct in different levels. The alpha -fibrinogen chain was partially protected against degradation caused by B. jararacussu venom, when this venom was in cubated with C. sylvestris extract. We also observed that this extract part ially increased the time of plasma coagulation caused by B. jararacussu, B. moojeni and B. neuwiedi venoms. C. sylvestris extract did not induce prote olysis in any substrate assayed. (C) 2001 Elsevier Science Ltd. All rights reserved.