Effect of chemical composition, extraction methods, and therapeutic efficacy of garlic oil against various cancer cell lines

Garlic oil is rich in organosulfur compounds (OSCs) that has significant anticancer effects. This study investigates the anticancer properties of garlic essential oil (GEO) at different concentration (0.5%, 0.25%, 0.125%, 0.0625%, 0.0312%, and 0.0156% V/V) and its bioactive components extracted through various methods, including hydrodistillation (HD), supercritical fluid (SCF), and ultrasound-assisted extraction (UEA). The chemical composition of garlic essential oils (GEOs) obtained using three extraction techniques has been studied by GC–MS analysis. GEO that was extracted by HD and SCF method contains almost the same percentage of the major constituents diallyl trisulfide and diallyl disulfide (63.16%) and (63.78) of the same components, respectively compared to GEO produced by UAE method. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay was performed to study the effects of garlic oil on five human cancer cell lines (Caco-2, HepG2, A549, MCF7, and PC3) for 24 and 48 h. Results demonstrated that GEO exhibits significant cytotoxic activity against all tested cancer cell lines, with varying levels of efficacy depending on the extraction method used. Proliferation of all cells was obviously inhibited in the first 24 hours with the MTT assay for oils extracted by SCF and UEA methods. The inhibition effect was more significant after 48 h for all oils. The IC50 values demonstrate the potential of GEO as a natural therapeutic agent in cancer treatment especially oils extracted by SCF. This research highlights the importance of garlic-derived compounds in developing effective anticancer therapies and encourages further exploration into their mechanisms of action.