Physicochemical, enzymatic and molecular characterisation of the storage protein of aerial tuber, Dioscorea bulbifera Linn.

BACKGROUND: The storage protein of the aerial tuber of Dioscorea bulbifera was purified and its physicochemical, enzymatic and molecular properties determined with a view to comparing its functionality and genetic relatedness with other storage proteins. RESULTS: The purified protein had molecular weight of 21 kDa. The protein showed carbonic anhydrase, trypsin inhibitory, dehydroascorbate reductase and monodehydroascorbate reductase activities. Amplifications with polymerase chain reactions resulted in the detection of two genes encoding the storage protein. The deduced amino acid sequence of the shorter and larger genes had homologies with the storage proteins of members of the Dioscorea family. CONCLUSION: The study concluded that the storage protein of the aerial tuber of D. bulbifera had similar properties with those of other Dioscorea species and may be suitable for development as functional food.