Bioefficacy of α-Bisabolol-rich essential oil separated from Curcuma inodora rhizome of Konkan region, India

Curcuma inodora Blatt., an ornate species from the Zingiberaceae family native to the peninsular region, holds unexploited medicinal potential. This study presents the first comprehensive report on the rhizome oil of C. inodora, integrating in-vitro, in-silico and in-vivo approaches. The essential oil was extracted using a relatively novel ultrasound-assisted solvent extraction method, employing ethanol as the solvent, with a yield of 0.69 %. GC/HRMS analysis identified α-Bisabolol (45.64 %), β-Thujene (17.25 %) and β-Bisabolene (14.24 %) as the major components. In-vitro antimicrobial activity was assessed using broth and agar dilution methods, while antioxidant potential was evaluated via 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO) radical scavenging assays. Anti-inflammatory properties were tested using three distinct protein inhibition-based methods. These evaluations reflect the plant's traditional use in folk medicine for treating microbial infections, inflammation and oxidative stress. SwissADME server was used for in-silico ADMET profiling. Acute oral toxicity was assessed in Wistar rats following OECD 423 guidelines, including histopathological analysis. The α-Bisabolol-rich oil exhibited potent antibacterial activity against all tested strains, strong antifungal action against Candida albicans, significant antioxidant activity in the NO assay and notable anti-inflammatory effects. The ADMET analysis indicated high gastrointestinal absorption, favorable bioavailability and no Lipinski rule violations. Toxicity studies showed an LD₅₀ > 2000 mg/kg, confirming safety. These significant bioactivities are primarily attributed to α-Bisabolol, a major constituent recognized for its pharmacological importance. Therefore, the α-Bisabolol enriched rhizome oil of C. inodora holds considerable therapeutic promise, justifying further pharmacological and clinical investigations for potential drug development.