Abstract
Nigella sativa, or black cumin, is used as a spice in cooking and as a food supplement like seeds or oil for its biological properties, including antioxidant capacity, anti-inflammatory action, and support for the immune system. In the present study, the chemical composition and biological activities of the Nigella sativa seeds' fatty oil (NS) were investigated. The analytical composition was carried out by several techniques, such as GC-MS spectrometry and (1)H- and (13)C-NMR spectroscopies using appropriate internal standards. The GC-MS analysis highlighted the presence of palmitic and linoleic acid as major compounds. The antioxidant potential was evaluated through the DPPH radical-scavenging assay, and, furthermore, the NS effect on intracellular reactive oxygen species (ROS) levels was assessed in HaCaT cells (non-tumorigenic human keratinocytes) under oxidative stress induced by hydrogen peroxide. The cytotoxic and genotoxic profiles were evaluated on Caco-2 cells (human colorectal adenocarcinoma cells) using the CCK-8 viability assay and the Comet assay, respectively. Overall, the results demonstrated that NS possessed antioxidant activity, as evidenced by concentration-dependent DPPH radical scavenging and reduced intracellular ROS levels in HaCaT cells under oxidative stress. In Caco-2 colorectal cancer cells, NS induced significant cytotoxicity and DNA damage at higher concentrations, suggesting potential genotoxic effects. These findings support the dual role of NS as a natural antioxidant and a promising candidate for nutraceutical and dermatological applications, including those targeting oxidative stress-related conditions and cancer.