A comparison on the nutritional quality of proteins from Moringa oleifera leaves and seeds

Abstract

The aim of this study was to evaluate the nutritional quality of protein from Moringa oleifera seeds and leaves. The defatted flours were rich in protein (33.53 and 18.63% for seeds and leaves, respectively) and carbohydrates. Amino acid analysis revealed the presence of all essential amino acids in both leaf and seed flour, with high content of leucine and valine and low content of methionine and cysteine. The total essential amino acids content of leaf flour (42.76 g/16 g N) was higher than that of seed flour (35.07 g/16 g N). Limiting amino acids were lysine and sulfur amino acids. The available lysine content of leaf flour (3.78 g/16 g N) was significantly higher than that of seed flour (1.30 g/16 g N). In vitro digestibility studies revealed that leaf proteins were more easily digested by pepsin than seed proteins. Moreover, after a pepsin-pancreatin hydrolysis, digestibility of seed flour (61.12%) was significantly higher than that of leaf flour (57.22%). In addition, the leaf flour showed higher chemical score (72.40%), protein efficiency ratio (3.47–3.71) and protein digestibility corrected amino acid score (41.42%) and available lysine (3.78 g/16 g N) than the seed flour. Therefore, M. oleifera seeds and leaves have good potential as nutritional supplements or ingredients in food.

Keywords

• moringa oleifera
• seeds
• leaves
• proteins quality