Chemical Composition, Preliminary Toxicity, and Antioxidant Potential of Piper marginatum Sensu Lato Essential Oils and Molecular Modeling Study

Abstract

The essential oils (OEs) of the leaves, stems, and spikes of P. marginatum were obtained by hydrodistillation, steam distillation, and simultaneous extraction. The chemical constituents were identified and quantified by GC/MS and GC-FID. The preliminary biological activity was determined by assessing the toxicity of the samples to Artemia salina Leach larvae and calculating the mortality rate and lethal concentration (LC50). The antioxidant activity of the EOs was determined by the DPPH radical scavenging method. Molecular modeling was performed using molecular docking and molecular dynamics, with acetylcholinesterase being the molecular target. The OES yields ranged from 1.49% to 1.83%. The EOs and aromatic constituents of P. marginatum are characterized by the high contents of (E)-isoosmorhizole (19.4–32.9%), 2-methoxy-4,5-methylenedioxypropiophenone (9.0–19.9%), isoosmorhizole (1.6–24.5%), and 2-methoxy-4,5-methylenedioxypropiophenone isomer (1.6–14.3%). The antioxidant potential was significant in the OE of the leaves and stems of P. marginatum extracted by SD in November (84.9 ± 4.0 mg TE·mL−1) and the OEs of the leaves extracted by HD in March (126.8 ± 12.3 mg TE·mL−1). Regarding the preliminary toxicity, the OEs of Pm-SD-L-St-Nov and Pm-HD-L-St-Nov had mortality higher than 80% in concentrations of 25 µg·mL−1. This in silico study on essential oils elucidated the potential mechanism of interaction of the main compounds, which may serve as a basis for advances in this line of research.

Chemical Composition of Piper nigrum L. Cultivar Guajarina Essential Oils and Their Biological Activity

“…Subsequently, the LC50 value was determined through semilogarithmic interpolation, converting mortality percentages into probits. As a positive standard for the control group, lapachol, a naphthoquinone extracted from the bark of various Tabebuia species (Bignoniaceae), renowned for its broad biological activity against diverse organisms, was employed [ 40 ].…”

“…For the control reaction, 50 μL of Trolox 1 mM in ethanol was substituted for the sample (resulting in a final concentration of 25 μM in the reaction). The calculation of the inhibition percentage (DPPH %) was performed as described in the literature to determine the percentage of inhibition of DPPH radicals (DPPH) [ 40 ].…”

Morphoanatomical, Histochemical, and Essential Oil Composition of the Plectranthus ornatus Codd. (Lamiaceae)

“…Essential oils (EOs) are formed by complex mixtures of volatile substances. These oils are biosynthesized in the secondary metabolism of plants, and several classes of compounds can be identified in essential oils such as monoterpenes, sesquiterpenes, and phenylpropanoids [ 7 , 8 , 9 , 10 , 11 ]. These complex mixtures is strongly volatile according to abiotic environmental factors.…”