Comparative study of the structural and functional properties of protein isolates prepared from edible vegetable leaves

September 21, 2022

Title

Comparative study of the structural and functional properties of protein isolates prepared from edible vegetable leaves

Author

Akinsola A. Famuwagun, Adeola M. Alashi, Saka O. Gbadamosi, Kehinde A. Taiwo, Durodoluwa J. Oyedele, Odunayo C. Adebooye & Rotimi E. Aluko

Year

2020

Journal

International Journal of Food Properties, 23:1, 955-970

Abstract

Isoelectric precipitation was used to produce protein isolates (>90% protein
contents) from three edible vegetable leaves. Amaranth (ALI), eggplant (ELI)
and fluted pumpkin (FLI) leaf protein were isolated to study their conformational structures. Intrinsic fluorescence indicated a loose structural conformation for ELI at all the pH values, whereas FLI and ALI had more compact
structures at pH 3.0 and pH 9.0. The surface hydrophobicity showed a greater
distribution of hydrophobic amino acid groups of the protein isolates at the
basic than the acidic regions. The SDS-PAGE results showed that the leaf
isolates had similar polypeptide bonds characterized by 20, 25, 40 and 200
kDa and some distinct bands above 200 kDa. The ELI formed emulsions with
significantly (p < .05) smallest oil droplet sizes (<3.3 µm) when compared to FLI and ALI. However, foaming capacity was mostly pH-dependent with significantly (p < .05) higher values at pH 7.0 and 9.0. The leaf protein isolates may be considered as potential functional food ingredients.

Instrument

FP-6300, J-810

Keywords

Leaf, protein isolate, Intrinsic fluorescence, gel electrophoresis, functional properties