GC–MS-based chemometric profiling of volatile oils from Ocimum varieties reveals bioactive markers associated with anti-skin cancer activity

Abstract Skin cancer is the most commonly diagnosed cancer worldwide. Basil oils have been traditionally used for alleviating various diseases. This study investigated the chemical profile and anticancer activity of five basil oils’ varieties (purple, lemon, Italian, Asian, and local). Hydrodistilled oils were analyzed using GC–MS, identifying 44 volatile constituents mainly belonging to oxygenated monoterpenes and phenylpropanoid derivatives. PCA and OPLS-DA analyses demonstrated classification into three clusters: lemon basil, Italian basil, and a third group including purple, Asian, and local basil. Linalool and eugenol were identified as key markers for lemon and Italian basil, respectively. Lemon basil exhibited the most potent anticancer activity against the human epidermoid carcinoma cell line (A431), with a high selectivity index. PLS regression attributed this activity to linalool, neral, and geranial. Mechanistically, lemon basil oil induced antiproliferative effects via S-phase arrest and promoted apoptosis, as confirmed by annexin V-FITC/PI staining. Additionally, p53 and Bax proteins were upregulated. The oil showed modest inhibitory activity against CDK2 and TrkA (IC 50 = 55.4 and 103.99 µg/mL), which was consistent with docking analysis of the most abundant compound; linalool. Lemon basil oil represents a promising candidate for skin cancer therapy, warranting further investigation of its active constituents. Consequently, lemon basil oil would be a promising remedy against skin cancer after performing further safety and efficacy studies.