Evaluating the inhibitory activity of lemongrass essential oil against some pathogenic fungi

Background: Fungal skin infections are a rising global health concern due to increasing resistance to conventional antifungal agents and significant side effects of synthetic drugs. Plant-derived essential oils, such as lemongrass (Cymbopogon flexuosus) oil, offer a promising natural alternative with potential antifungal and antioxidant activities. Objectives: To characterize the chemical composition of lemongrass essential oil and evaluate its in vitro antioxidant capacity and antifungal efficacy against Candida tropicalis (ATCC 66029) and Cryptococcus neoformans (ATCC 14116). Methods: Lemongrass leaves, collected from Baghdad University gardens, were steam-distilled to obtain essential oil. Chemical profiling was performed by GC–MS. Antioxidant activity was assessed via DPPH radical scavenging assay at concentrations of 12.5–200 µg/mL. Antifungal efficacy (MIC) was determined by agar-dilution in Sabouraud Dextrose Agar plates containing 62.5–2000 µg/mL oil, with inocula of ~1×10^5 CFU per plate. Results: GC–MS revealed a citral-rich chemotype (89.38%) with minor constituents β-caryophyllene (6.13%) and geranyl acetate (2.39%). The oil exhibited dose-dependent DPPH scavenging, achieving 80.98% inhibition at 200 µg/mL (vs. 85.65% for ascorbic acid). MICs were 250 µg/mL for C. tropicalis and 175 µg/mL for C. neoformans, indicating potent antifungal activity. Conclusions: Lemongrass essential oil demonstrates strong antioxidant and notable antifungal properties at concentrations suitable for topical formulations. Its citral-dominant profile suggests membrane-targeting mechanisms. Further work should focus on formulation development, in vivo efficacy, and safety evaluations to advance its use as a natural antifungal agent.