Serine proteases activity in miracidia of Fasciola hepatica and effects of chemical and herbal inhibitors

Document Type : Original Article


1 MSc Graduated

2 Academic staff

3 Department of Basic Sciences, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran



Fasciolosis is a zoonotic parasitic disease caused by the trematode Fasciola hepatica. The proteases are essential for the survival of parasites. The present study was aimed to determine serine proteases activities in miracidia of F. hepatica and evaluate the effects of pH and different inhibitors on the serine proteases activities. For this purpose, adult F.hepatica helminths were removed from naturally infected livers of the slaughtered cattle and crushed. Fasciola hepatica eggs incubated at 28°C for 16 day. The released miracidia were homogenized and total proteolytic activity of the extract of miracidia at different pH values evaluated. Serine proteases activities were determined by using specific substrates. The inhibitory effects of chemical and herbal inhibitors on the enzymes were also assessed. The extract of miracidia hydrolyzed azocasein with optimum activity at pH 8. The optimum pH effect on serine proteases activities was found at alkaline pH. PMSF and Bowman-Birk inhibitors inhibited and decreased the proteases activities in the miracidia extract. It was concluded that there was proteases activities in miracidia of F. hepatica which inhibited by chemical and herbal inhibitors.


Articles in Press, Accepted Manuscript
Available Online from 14 June 2021
  • Receive Date: 19 December 2018
  • Revise Date: 26 February 2019
  • Accept Date: 21 May 2019