Phytochemical analysis and aging assessment of canola seeds supported by hyperspectral imaging

Canola ( Brassica napus L.) is a major oilseed crop whose germination, nutritional reserves, and physiological performance are strongly dependent on seed vigor. Seed aging represents a critical abiotic stress that reduces viability, disrupts metabolic balance, and compromises oil quality. In this study, we examined biochemical, phytochemical, nutritional, and physiological alterations in canola seeds subjected to accelerated aging, alongside seedling performance and oil characteristics. Aging shifted primary metabolism, with carbohydrate levels increasing and protein content declining, while essential vitamins (C, E, folic acid) and bioactive compounds (phenols, flavonoids, flavonols) were markedly reduced, indicating diminished antioxidant capacity. Although vitamin B 12 was initially analyzed, its results were excluded due to serum-based assay cross-reactivity and lack of plant-matrix validation. Oil from aged seeds showed oxidative degradation, including sharp declines in unsaturated fatty acids (oleic from 28.9% to 25.8%, linoleic from 20.5% to 12.3%, linolenic from 15.2% to 8.9%), loss of δ-tocopherol and sterols, and reduced chlorophyll, although refractive index and saponification value remained stable. Physiological assessments paralleled these changes, showing reduced germination, weaker seedling vigor, and increased electrolyte leakage, reflecting membrane damage. Most importantly, hyperspectral imaging (HSI) proved to be a rapid, non-invasive method to detect seed aging. Reflectance spectra (400–800 nm), analyzed using MSC normalization and Boruta feature selection, identified key wavelengths linked to deterioration. Unsupervised analyses (PCA, heat mapping) clearly separated aged from control seeds. Collectively, these findings demonstrate that accelerated aging severely undermines seed vigor, biochemical integrity, and oil quality. The application of HSI provides a valuable tool for seed physiology and stress biology, enabling the monitoring of viability loss, improving conservation practices, and enhancing the understanding of seed deterioration processes.