GC-MS Characterization, In Vitro Antioxidant, Anti-inflammatory and Potential Antidermatophytic Activity of Citrullus lanatus Seed Oil

Background: Dermatophytes are well-known fungus having the capability to invade keratinized tissues of nails, skin, and hair, of humans and other animals, causing dermatophytosis. Citrullus lanatus (watermelon) seed is a rich source of vitamin E, essential fatty acids, and minerals, bearing various health benefits. Despite the presence of many useful components, the oil is not much explored. Accordingly, the study was planned to investigate the fatty acid profiling, in vitro antioxidant, anti-inflammatory, and potential antidermatophytic activity of Citrullus lanatus seed oil against dermatophytic strains.

Methods: The C. lanatus oil was extracted from seeds, and fatty acid profiling was characterized by GC-MS. Further, the oil was subjected to DPPH scavenging activity, and the anti-inflammatory activity was evaluated from Bovine serum albumin assay. The antidermatophytic screening against Microsporum canis, Trichophyton rubrum, and Trichophyton mentagrophytes was carried out by agar well diffusion, broth microdilution assay, and growth kinetics assay.

Results: The C. lanatus seed oil exhibited good antioxidant activity close to ascorbic acid, i.e., IC50- 52.22 μg/ml, 35.72 μg/ml, respectively, and the oil exhibited moderate anti-inflammatory activity (315.2 μg/ml) as that of the standard drug diclofenac sodium (174.3μg/ml). The fatty acid profiling indicates the presence of eight main compounds, out of which ç-tocopherol, butylated hydroxytoluene, and hexadecanoic acid are predominantly present. The C. lanatus seed oil showed promising activity against T. rubrum with a lower minimum inhibitory concentration value with respect to positive controls, Fluconazole and Ketoconazole. The oil also had a strong effect on timedependent kinetic inhibition against T. rubrum. This was the first report of C. lanatus seed oil against any dermatophyte.

Conclusion: In conclusion, the study supports the exploitation of C. lanatus seed oil and its main compounds as a source of natural antioxidants, anti-inflammatory, and as a novel agent against dermatophytes for curing superficial fungal infections in the near future.