Isolation of proteinase inhibitors from okra for inhibiting the Helicoverpa armigera (Hubner) gut proteinases

Experiment was conducted to estimate the protein content and inhibitory potential of different genotypes of okra and its wild relatives towards trypsin and chymotrypsin in in vitro. The wild relatives of okra possessed high protein content as compared to the cultivated genotypes. From wild relatives A. tuberculatus (90396 and 90515) contained high protein content up to 3.31 mg g⁻¹ and 3.27 mg g⁻¹ seed flour, respectively. The wild relatives of okra PIs from A. tuberculatus (90396 and 90515) inhibited the maximum trypsin activity i.e. upto 68.1 and 66.9 per cent, whereas, the chymotrypsin activity was found to be 68.4 and 65.8 per cent respectively. On the other hand VRO-3 and AKO-102 exhibited 63.3 and 62.2 per cent trypsin activity, also least chymotrypsin activity found upto 62.4 and 61.1 per cent. Since the proteinase inhibitors of wild relatives of okra possessed higher trypsin inhibitory potential than cultivated ones.