Comparative analysis of phytochemical traits, proximate composition, and metabolite diversity in Nigella sativa L....

Nigella is a medicinal cum spice plant and is celebrated for its minute, distinctive black seeds and is native to Africa, Asia and the Mediterranean region. The present study aimed to assess variation in oil yield, biochemical composition, phytochemical traits, metabolite diversity, fatty acid profile, and nutritional indices using multivariate analysis. Oil yield displayed a broad range, from 9.96% in NSC‑16 to 29.93% in NSC‑6. GC-MS profiling revealed linoleic acid as the predominant fatty acid, accompanied by notable levels of oleic, palmitic, and stearic acids. Polyunsaturated fatty acids (PUFA) represented the major lipid fraction (57.11-71.92%), yielding favorable nutritional indices (PUFA/SFA:3.52-5.45; MUFA+PUFA/SFA: 4.52-6.95). Thymoquinone content exhibited pronounced chemotypic variation, peaking at 247.6 µg/100 mg seed in AN‑13. Phenolic, Flavonoid density ranged approximately ~ 2.5 to 11 mg g⁻¹ oil and ~ 0.6-2.8 mg g⁻¹ oil respectively and the thymoquinone index ranged ~ 0.3 to ~ 1.6 mg g⁻¹ oil. Distinct patterns in antioxidant activity, carbohydrate allocation, and bioactive metabolite indices highlighted strong metabolite specialization among genotypes. Multivariate analysis pinpointed NSC‑6, NSC‑5, AN‑8, AN‑11, AN‑12, AN‑2, NSC‑1, NSC‑2, AN‑35, and AN‑13 as superior genotypes, integrating high oil yield, PUFA enrichment, robust antioxidant activity, and elevated bioactive compound accumulation. These elite lines represent valuable resources for nutraceutical innovation, functional food development, and targeted breeding strategies aimed at enhancing health‑promoting traits.