Serine proteases activity in miracidia of and effects of chemical and herbal inhibitors.

Fasciolosis is a zoonotic parasitic disease caused by the trematode . The proteases are essential for the survival of parasites. The present study was aimed to determine serine proteases activities in miracidia of and evaluate the effects of pH and different inhibitors on the serine proteases activities. Adult helminths were removed from naturally infected livers of the slaughtered cattle and crushed. The eggs were incubated at 28.00 ˚C for 16 days. The released miracidia were homogenized and total proteolytic activity of the extract of miracidia at different pH values were evaluated. Serine proteases activities were determined 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 8.00. The optimum pH effect on serine proteases activities was found at alkaline pH. Phenylmethylsulfonyl fluoride and Bowman-Birk inhibitors inhibited and decreased the proteases activities in the miracidia extract. It was concluded that there were proteases activities in miracidia of which were inhibited by chemical and herbal inhibitors.