The essential oil from Citrus limetta Risso peels alleviates skin inflammation: In-vitro and in-vivo study

Citrus fruit peels are traditionally used in folk medicine for the treatment of skin disorders but it lacks proper pharmacological intervention. Citrus limetta Risso (Rutaceae) is an important commercial fruit crops used by juice processing industries in all continents. Ethnopharmacological validation of an essential oil isolated from its peels may play a key role in converting the fruit waste materials into therapeutic value added products.

To evaluate the chemical and pharmacological (in-vitro and in-vivo) profile of essential oil isolated from Citrus limetta peels (Clp-EO) against skin inflammation for its ethnopharmacological validation.

Hydro-distilled essential oil extracted from Citrus limetta peels (Clp-EO) was subjected to gas chromatography (GC) analysis for identification of essential oil constituents and its anti-inflammatory evaluation through in vitro and in vivo models.

Chemical fingerprint of Clp-EO revealed the presence of monoterpene hydrocarbon and limonene is the major component. Pre-treatment of Clp-EO to the macrophages was able to inhibit the production of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) in LPS-induced inflammation as well as the production of reactive oxygen species (ROS) in H₂O₂-induced oxidative stress. In in-vivo study, topical application of Clp-EO was also able to reduce the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced ear thickness, ear weight, lipid peroxidation, pro-inflammatory cytokines production and ameliorate the histological damage in the ear tissue. In-vitro and in-vivo toxicity study indicate that it is safe for topical application on skin.

These findings suggested the preventive potential of Clp-EO for the treatment of inflammation linked skin diseases.