Abstract

The study focused on the inhibition of the caseinolytic activity of Bitis arietans venom by aqueous methanol crude root extracts of Teclea nobilis and Vepris zambesiaca. Snake venom samples were collected from Snake World near Harare, and the medicinal plants were obtained from Mash Central Province, Zimbabwe. Data on the kinetics of the digestion of casein by the B. arietans venom and the inhibition of the caseinolytic activity of the venom were generated spectrophotometrically. Lineweaver-Burk plots to explore the kinetics of the digestion of casein by B. arietans venom gave V_max and K_M values of 8.33 × 10³ mol dm^-3 s^-1and 7.35 × 10⁶ mol dm^-3, respectively. Maximum inhibition of caseinolytic activity of the B. arietans venom of 70 and 60% was observed when incubation was performed in the presence of 6.25 and 8.50 µg/ml of T. nobilis and V. Zambesiaca, respectively. The inhibitory effect of the extracts was correlated to the levels of flavonoids, flavonols and phenolics. The results demonstrate that T. nobilis and V. zambesiaca have great potential as medicinal plants and are possible candidates for new therapeutic agents in the treatment of snake bite envenomations.

Key words: Bitis arietans, inhibition, caseinolytic effect, Teclea nobilis, Vepris zambesiaca.