Proximate Composition, Amino Acid Profile, and Phytochemical Properties of African Yam Bean (Sphenostylis stenocarpa) and Fluted Pumpkin (Telfairia occidentalis) Seed Flours
Etim Esin Etim *
Department of Biochemistry, Joseph Sarwuan Tarka University, Makurdi, Nigeria.
Lawrence Uchenna Sunday Ezeanyika
Department of Biochemistry, University of Nigeria, Nsukka, Nigeria.
Stephen Sule
Department of Food Science and Technology, Joseph Sarwuan Tarka University, Makurdi, Nigeria.
Abutu Christiana Agbenu
Department of Biochemistry, Joseph Sarwuan Tarka University, Makurdi, Nigeria.
Iwueke Goodness Chioma
Department of Biochemistry, Joseph Sarwuan Tarka University, Makurdi, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Underutilized seed flours from African yam bean (Sphenostylis stenocarpa) and fluted pumpkin (Telfairia occidentalis) were evaluated for proximate composition, amino acid profile, and phytochemical constituents. Significant variations (P < .05) were observed in proximate composition. Moisture content ranged from 5.45–7.32%, crude protein from 26.62–30.38%, crude fibre from 1.32–8.28%, fat from 1.45–34.56%, ash from 2.18–3.31%, and carbohydrate from 18.02–61.11%. Fluted pumpkin seed flour exhibited higher protein, fibre, lipid, and ash contents, whereas African yam bean showed higher moisture and carbohydrate levels. Both seed flours revealed the presence of essential and non-essential amino acids. Flour from fluted pumpkin contained higher levels of serine (8.60 g/100 g), proline (30.35 g/100 g), isoleucine (30.25 g/100 g), lysine (3.43 g/100 g), histidine (1.55 g/100 g), and tyrosine (3.95 g/100 g), whereas African yam bean seed flour recorded higher alanine (15.62 g/100 g) and valine (8.59 g/100 g). Glycine was detected only in African yam bean flour (11.86 g/100 g). Fluted pumpkin seed flour showed higher levels of bioactive compounds, including epicatechin (8.65 µg/g), quercetin (4.35 µg/g), gallocatechin-3-gallate (5.65 µg/g), and myricetin (3.45 µg/g), while African yam bean flour contained notable levels of genistein (1.22 µg/g), naringenin (2.00 µg/g), and artemetin (1.04 µg/g). Resveratrol and apigenin were detected only in fluted pumpkin seed flour. These results demonstrate that both seed flours possess valuable nutritional and phytochemical attributes, highlighting their potential as alternative plant protein sources and functional ingredients for food formulation.
Keywords: Underutilized seed flours, African yam bean, fluted pumpkin seed, functional foods, indigenous crops, plant protein