Chemical Characterization of Seed Proteins of Mirabilis jalapa L. (Nyctaginaceae)

This article investigated chemical characteristics of Mirabilis jalapa seed proteins. Proteins were extracted from the deoiled seeds of Mirabilis jalapa L. in aqueous solutions at various pH values and also by using different concentrations of NaCl, Na ₂SO ₄, CaCl ₂, and MgSO ₄ at pH 7.0. The nitrogen content (1.77 ± 0.23 g/100 seed) of the seeds and deoiled seeds showed high protein content (11.0 ± 0.75 g/100 seed). Amino acid analyses of the total protein isolates confirmed the presence of 17 amino acids of which 9 are essential. The molecular weight of total protein isolates was determined by gel filtration and sodium dodecyl sulphate-poly acrylamide gel electrophoresis method. Studies on surface structure of the total protein isolates and seed flour by scanning electron microscopy were also performed.