Pharmacological investigation of Ajuga iva essential oils collected at three phenological stages

Ajuga iva (A iva) is a medicinal plant used mainly in traditional medicine. This study was aimed to identify the volatile compounds of A iva essential oils (AIEO) at three developmental periods, and to evaluate their pharmacological properties. Chemical volatile compounds were identified by GC/MS analysis. Twenty‐eight volatile components were identified, belonging mainly to oxygenated monoterpenes and hydrocarbons monoterpenes. Carvacrol, octadecane, methyl chavicol were the major volatile components of AIEO at the three phenological stages. FRAP, DPPH and ABTS assays were adopted to estimate the antioxidant effects. AIEO at the vegetative stage exhibited important antioxidant effects with IC50 = 52.43 μg/mL (DPPH), IC50 = 115.22 μg/mL (FRAP), and, IC50 = 143.40 μg/mL (ABTS). The antidiabetic activity was evaluated in vitro by the inhibition of α‐amylase and α‐glucosidase. AIEO at the vegetative stage was the most active as an enzyme inhibitor of α‐amylase (IC50 = 101.727 μg/mL) and α‐glucosidase (IC50 = 86.93 μg/mL). The dermatoprotective effect was investigated by the in vitro inhibition of tyrosinase and elastase activities. AIEO at the vegetative stage showed the lowest IC50 inhibition values against tyrosinase (IC50 = 87.49 μg/mL) and elastase (IC50 = 192.21 μg/mL). Antifungal properties of AIEO were investigated on Trichophyton violaceum, T tonsurans and T mentagrophytes. The three EOs of A iva exhibited important inhibitions of the tested dermatophytes. The findings of this work showed that phenological stages affect significantly the volatile compounds of A iva, and these fluctuations influence mainly the biological properties. Moreover, further investigations concerning in vivo pharmacodynamic and pharmacokinetic investigations as well as clinical trials of these identified compounds could develop antidiabetic, dermatoprotective and anti‐dermatophyte drugs. The findings of this work showed that phenological stages affect significantly the volatile compounds of A iva, and these fluctuations influence mainly the biological properties.