Targeted phytochemical profiling and functional evaluation of bitter and sweet Lupinus albus genotypes from diverse origins

Bitter Lupinus albus genotypes, traditionally excluded from food use due to high alkaloid levels, are reassessed as underutilized sources of bioactive phytochemicals. This study conducted a comparative agro-morphological and biochemical analysis of bitter and sweet genotypes. Targeted GC–MS profiling revealed that bitter types exhibited accelerated phenological development and significantly higher levels of stearic, behenic, and α-linolenic acids. They also demonstrated enhanced antioxidant capacity (DPPH IC₅₀: 23.4 ± 2.1 vs. 41.2 ± 3.7 μg/mL) and stronger lipoxygenase-inhibitory activity. Lupanine was the dominant alkaloid in bitter seeds, while erucic acid remained within acceptable dietary limits. Sweet genotypes maintained low alkaloid content and favourable fatty acid ratios. Antifungal assays indicated stronger inhibition of Colletotrichum acutatum by bitter types. Principal component analysis highlighted clear genotype-dependent clustering based on phenological, biochemical, and functional traits. These results support the valorisation of bitter L. albus for functional food applications and breeding strategies aimed at enhancing nutritional properties.