Tyrosinase inhibitory activity, molecular docking studies and antioxidant potential of chemotypes of Lippia origanoides (Verbenaceae) essential oils

Abstract

The essential oils (EOs) of the aerial parts of Lippia origanoides (LiOr), collected in different localities of the Amazon region, were obtained by hydrodistillation and analyzed by GC and CG-MS. Principle component analysis (PCA) based on chemical composition grouped the oils in four chemotypes rich in mono- and sesquiterpenoids. Group I was characterized by 1,8-cineole and α-terpineol (LiOr-1 and LiOr-4) and group II by thymol (LiOr-2). The oil LiOr-3 showed β-caryophyllene, α-phellandrene and β-phellandrene as predominant and LiOr-5 was rich in (E)-nerolidol and β-caryophyllene. All samples were evaluated for antioxidant activity and inhibition of tyrosinase in vitro and in silico. The highest antioxidant activity by the DPPH free radical method was observed in LiOr-2 and LiOr-5 oils (132.1 and 82.7 mg TE∙mL-1, respectively). The tyrosinase inhibition potential was performed using L-tyrosine and L-DOPA as substrates and all samples were more effective in the first step of oxidation. The inhibition by samples LiOr-2 and LiOr-4 were 84.7% and 62.6%, respectively. The samples LiOr-1, LiOr-4 and LiOr-5 displayed an interaction with copper (II) ion with bathochromic shift around 15 nm. In order to elucidate the mechanism of inhibition of the main compounds, a molecular docking study was carried out. All compounds displayed an interaction between an oxygen and Cu or histidine residues with distances less than 4 Å. The best docking energies were observed with thymol and (E)-nerolidol (-79.8 kcal.mol-1), which suggested H-bonding interactions with Met281 and His263 (thymol) and His259, His263 ((E)-nerolidol).

Chromatographic Analyses, In Vitro Biological Activities, and Cytotoxicity of Cannabis sativa L. Essential Oil: A Multidisciplinary Study

“…These variations observed can be explained by the different phytochemical compositions of the C. sativa samples. For example, the EO is richer in terms of volatile components, such as ( E )-caryophyllene, caryophyllene oxide, and humulene, which are known as anti-tyrosinase agents [71]. Similarly, naringenin, the major compound in the EO, is very active on α-glucosidase and pancreatic lipase [72,73].…”

Chemodiversity and biological activity of essential oils from three species from the Euphorbia genus

“…Alongside the in silico evaluation, an extensive bibliographic research was conducted for each selected substance for further validation of the results. Notably, the compounds 39 (thymol) 73 and 42 (α-bisabolol) 74 were found to be previously reported as tyrosinase inhibitors. In addition, the antioxidant property of thymol has been established to be a key characteristic for the inhibitory mechanism of melanin synthesis.…”

Bioactive Constituents of F. esculentum Bee Pollen and Quantitative Analysis of Samples Collected from Seven Areas by HPLC

“…The investigation of tyrosinase inhibitors may lead to the development of new skin-whitening substances, medicinal agents and anti-browning constituents [26]. Various potential tyrosinase inhibitors from natural products have been found, and they have attracted attention because of their safety and abundance [27]. This promote us to investigate the tyrosinase inhibitory activity isolated from F. esculentum bee pollen.…”