Global trends favor plant-derived bioactive compounds as eco-friendly alternatives to synthetic drugs. This is driven by consumer demand for natural solutions that provide effective treatments with potential environmental safety, thus supporting sustainable healthcare. In this study, the active compounds and the antioxidant, antimicrobial, cytotoxic, and hepatoprotective properties of essential oils (EOs) derived from three basil cultivars were evaluated, with a focus on lemon basil essential oil (LEO) in the context of CCl₄-induced hepatotoxicity in rats. The main volatile compound in LEO was methyl cinnamate (42.02%). LEO significantly inhibited 93% of DPPH and had broad-spectrum antimicrobial effects against pathogenic microbial isolates in the animal body, specifically gut, skin, and dental tissues, causing inflammation and tissue destruction (Listeria monocytogenes, Bacillus cereus, Staphylococcus aureus, Campylobacter jejuni, Escherichia coli, Salmonella typhi, Pseudomonas aeruginosa, Porphyromonas gingivalis, Enterococcus faecalis, Candida tropicalis, and Candida albicans), with MIC values (0.125–0.5 mg/mL). It also exhibited potent cytotoxicity against HepG2 liver cancer cells (86% inhibition at an IC₅₀ of 20 μg/mL). In vivo, CCl₄ administration induced significant hepatotoxicity, evidenced by elevated liver enzymes, increased oxidative stress markers (LOOH, AOPP), reduced antioxidant defenses (GSH, SOD, CAT, GPx), upregulated inflammatory markers (TNF-α, IL-6), and severe histopathological alterations. Importantly, LEO pretreatment significantly mitigated physiological distress, effectively reducing body weight loss and suppressing hepatomegaly, confirming its role in stabilizing key physiological parameters without adverse effects. It also upregulated the antioxidant defense genes (Nrf2, HO-1, SOD, CAT) and downregulated pro-inflammatory genes (TNF-α, IL-6). LEO also exerted protective effects against CCl₄-induced hepatotoxicity. In vivo evidence demonstrates that LEO activates Nrf2-mediated antioxidant defense and modulates the gut microbiome, thereby establishing a liver-gut protective synergy. It concluded that LEO offers a sustainable, multi-target nutraceutical alternative to synthetic liver drugs by dual-regulating oxidative and inflammatory genes.

To Cite This Article: Alharbi A, Bel Hadj Salah K, Shakak AO, Alhasnani MA, Alamoudi RA, Aldawood N, Alruhaimi RS, Alsolami AM, Aljhdli MO, Aljazzar A and Hamdi N, 2026. Biochemical characterization of some basil cultivars extracts with biological activities on physiological, immunological, antioxidant properties, and modulation of defense genes in carbon tetrachloride-induced rats. Pak Vet J, 46(6): 1403-1416. http://dx.doi.org/10.29261/pakvetj/2026.135