Enzyme inhibitors from plants: Enterokinase inhibitors in tubers and seeds.

Of the 22 tubers and 9 pulses screened for inhibitors of enterokinase activity, the following 12 tubers, Curcuma amada, Kyllinga monocephala, Solanum tuberosum, Canna indica, Helianthus tuberosus, Coleus parviformis, Mirabilis jalapa, Colocasia antiquorum (red variety), Alium cepa, Arnorphophalus companulatus, Maranta arundinacea, Daucus carota, and 9 pulses namely, Vigna sinensis, Arachis hypogea, Pisum sativum, Phaseolus vulgaris (white bean), Phaseolus vulgaris (kidney bean), Phaseolus mungo, Cicer arietinum, Dolichos lablab and Cajonus cajan contained inhibitory activity. Three tubers, Arnorphophalus companulatus, Maranta arundinacea and Daucus carota and all the nine pulses exhibited endogenous esterase activity towards benzoyl arginine ethyl ester. Among the 8 pulses and 3 tubers processed by affinity chromatography on trypsin sepharose, to separate trypsin inhibitor from enterokinase inhibitor, Phaseolus vulgaris (kidney bean), Phaseolus vulgaris (white bean) and Dolichos lablab contained distinct enterokinase inhibitors. These fractions were devoid of trypsin inhibitor activity. The trypsin inhibitor from Coleus parviformis tubers alone did not bind to trypsinsepharose and was recovered in the unbound fraction along with the enterokinase inhibitor.