Chemical Composition, Anti-Tyrosinase and Antioxidant Potential of Essential Oils from Acorus calamus (L.) and Juniperus communis (L.)

The essential oils (EOs) represent a natural source of diverse phytoconstituents that may exert a wide range of health-promoting effects, including antioxidative, anti-inflammatory, antimicrobial, and immunomodulatory activities. Compounds with antioxidative and anti-tyrosinase properties present in EOs may suppress excessive melanin production and protect skin cells from oxidative stress factors that often aggravate the pigmentation process. <i>Acorus calamus</i> L. and <i>Juniperus communis</i> L. plants have been traditionally used in phytotherapy, either individually or in combination. However, the biological and pharmacological effects of the essential oils derived from <i>A. calamus</i> rhizomes (EOA) and <i>J. communis</i> cone-berries (EOJ) remain underexplored. This study aimed to evaluate (1) the chemical composition of both EOA and EOJ using the gas chromatography-mass spectrometry (GC-MS) technique; (2) the anti-tyrosinase activity of the two examined EOs; and (3) their antioxidant potential against DPPH and ABTS free radicals. In addition, the anti-tyrosinase and antioxidant activities of mixtures of EOA and EOJ were also investigated. GC-MS analyses identified 48 and 81 chemical compounds in the EOA and EOJ, respectively. The main constituents of the EOA were sesquiterpenoids, including acorenone (18.1%), preisocalamendiol (12.0%), shyobunone (7.5%), and isoshyobunone (5.7%). In contrast, EOJ was primarily composed of α-pinene (22%), a monoterpene. In vitro analyses demonstrated that both individual and combined EOs exhibited notable antioxidant and anti-tyrosinase activities. The health-promoting potential of these EOs is discussed.