Proximate composition, lipid and phenolic profiles, and antioxidant activity of different ecotypes of Lupinus albus, Lupinus luteus and lupinus angustifolius

Lupine seed represents an interesting, non-genetically modified, and low cost alternative to soybean as an important source of protein and oil. In this study, we compare seed protein, mineral, fiber and starch content, lipid and phenolic profile, and antioxidant properties of three lupine wild species (Lupinus albus, Lupinus luteus, and lupinus angustifolius). For each lupine species, nutritional composition of different Tunisian ecotypes was compared to determine the influence of geographical origin on these compounds. Standard protocols and ultra-high-performance liquid chromatography/tandem mass spectrometry methods were used. Results revealed that several compounds showed a significant difference between species as well as between local ecotypes and commercialized variety. L. albus seeds were shown characterized by the highest protein and oleic acid content and the lowest starch content. Results revealed that lipids and phenolics were highly influenced by the ecotype factor. Large differences were found between L. luteus ecotypes for oleic acid and linoleic acid content, ranging from 164.97 to 302.73 mg kg(-1) DM and from 306.03 to 616.97 mg kg(-1) DM, respectively. Little amount of miristoleic acid, lignoceric acid, and margaric acid were found in lupine seeds for the first time. For phenolic profile, interestingly to highlight for the first time the presence of morin dihydrate among lupines species, especially in L. tbk2 which showed the highest antioxidant activity.

Automated summary

Lupine seed shows significant differences in nutritional composition between species and geographical ecotypes, with white lupine having the highest protein and oleic acid content, while yellow lupine ecotypes vary greatly in oleic and linoleic acid content. The lipid and phenolic profiles of lupine seeds are highly influenced by ecological factors, with some ecotypes showing unique compounds and antioxidant activities.