In Silico Evaluation of Potential DPP-III Inhibitor Precursors from Dietary Proteins

Dipeptidyl peptidase-III is an important enkephalin degrading enzyme and its inhibitors are expected to be promising in pain management. Some of its inhibitors showed an antinociceptive potential. The present study investigated the evaluation of dietary proteins as potential precursors of dipeptidyl peptidase-III inhibitors by measuring occurrence frequency of dipeptidyl peptidase-III inhibitory peptides. In silico analysis of 69 proteins from 17 food commodities revealed 2659 dipeptidyl peptidase-III inhibitory peptides. β-subunit of hemoglobin and annexin A5 of chicken showed highest dipeptidyl peptidase-III inhibiting potential followed by 12S seed storage globulin 2 of oat, β-conglycinin of soyabean, α-lactalbumin of cow milk, cruciferin CRU4 of rapeseed, and zein-alpha of maize But overall occurrence frequency of dipeptidyl peptidase-III inhibitory peptides was observed highest in maize followed by pumpkin, soyabean, and rapeseed, whereas barley showed the lowest frequency among plant based foods. Chicken and maize had the highest dipeptidyl peptidase-III inhibitory potential in animal and plant derived foods respectively, thus may serve as a natural dietary source for pain modulation.