Background and Aims: Organosulfur compounds modulate the activities of plurality of metabolic enzymes, especially those
that activate (cytochrome P450s) or detoxify (glutathione-S-transferases) carcinogens. They also inhibit the formation of DNA
adducts in different target tissues. The aim of the present study was to investigate the effect of some sulfur compounds on
urease and trypsin activities in vitro.
Methods: In the present study, the inhibitory effect of sulfur compounds on the activities urease and trypsin were determined
according to the method of Hanif et al. (2012) and Ribeiro et al. (2010), respectively.
Results: In comparison to the reference standard thiourea (IC50= 53.81±0.68 µg/mL), S-allyl-L-cysteine (IC50= 0.88±0.01 µg/
mL) and D, L-methionine (IC50= 0.91±0.02 µg/mL) had the highest urease inhibitor activity, corresponding to the lowest IC50
values among the sulfur compounds. Among the sulfur compounds used in this study, D,L-methionine (IC50= 0.13±0.01 mg/
mL) exhibited the lowest IC50 value for trypsin inhibitor, though its activity was less than that of tannic acid which was used
as a standard (IC50= 0.06±0.01 mg/mL).
Conclusion: The present outcome suggests that sulfur compounds are potential inhibitors of urease and trypsin activities,
and may find importance in medicine and agriculture.
Keywords: Enzyme, inhibitors, sulfur compounds, urease, trypsin