Chemical analysis and antityrosinase activities of some fixed oils used in aromatherapy

Aromatherapy is a treatment method that uses essential and fixed oils obtained from plants, dating back to BC. Essential oils used in topical treatment are dissolved in a fixed oil to reduce the risk of irritation. The bioactive components in the fixed oil provide a synergistic contribution to the effect of the essential oil. Hyperpigmentation disorders caused by the accumulation of melanin pigment, which gives its color to the human body, cause an undesirable appearance in terms of both health and beauty. It has been reported that phenolic compounds in the chemical components of fixed oils obtained by cold pressing have antioxidant and antityrosinase effects and have promising potential in the treatment of hyperpigmentation. For this aim, antioxidant activities, antityrosinase activities, total phenolic fractions and fatty acid compositions of cold-pressed fixed oils used in aromatherapy were researched. Effects were observed at various doses in the fractions obtained from Nigella sativa (black cumin), Pistacia terebinthus (terebinth tree) and Punica granatum (pomegranate) seed oils. The DPPH• scavenging effect of the phenolic fraction obtained from black cumin seed oil was observed at a dose of 17.5 µg/mL (IC50), while the tyrosinase inhibition effect was found to be 80% at a dose of 1.25 mg/mL. T he gallic acid equivalent of black cumin seed oil and the total phenolic content were determined as 178.61 mgGAE/g.