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The essential oils and aroma derived from the leaves (L), stems (St), and spikes (s) of Piper nigrum L. cv. Guajarina were extracted; the essential oils were extracted using hydrodistillation (HD), and steam distillation (SD), and the aroma was obtained by simultaneous distillation and extraction (SDE). Chemical constituents were identified and quantified using GC/MS and GC-FID. Preliminary biological activity was assessed by determining the toxicity against Artemia salina Leach larvae, calculating mortality rates, and determining lethal concentration values (LC50). The predominant compounds in essential oil samples included α-pinene (0–5.6%), β-pinene (0–22.7%), limonene (0–19.3%), 35 linalool (0–5.3%), δ-elemene (0–10.1%), β-caryophyllene (0.5–21.9%), γ-elemene (7.5–33.9%), and curzerene (6.9–31.7%). Multivariate analysis, employing principal component analysis (PCA) and hierarchical cluster analysis (HCA), revealed three groups among the identified classes and two groups among individual compounds. The highest antioxidant activity was found for essential oils derived from the leaves (167.9 41 mg TE mL−1). Larvicidal potential against A. salina was observed in essential oils obtained from the leaves (LC50 6.40 μg mL−1) and spikes (LC50 6.44 μg mL−1). The in silico studies demonstrated that the main compounds can interact with acetylcholinesterase, thus showing the potential molecular interaction responsible for the toxicity of the essential oil in A. salina. [ABSTRACT FROM AUTHOR]

The phytochemical analysis and potential synergistic interactions between the essential oils (EOs) of Vitex negundo L. Piper longum L. and Vitex agnus-castus L. and their pesticidal efficacy were the main focus of this study. To examine their synergistic interactions with pesticidal activities, the recovered EOs were mixed in binary and ternary combinations at similar ratios and the nematicidal activity of individual EOs and their mixtures was evaluated. Using the disc-diffusion method, antifungal activity was evaluated. For comparison means of biological activities, a two-way ANOVA was carried out, at a significance level of 5% (p < 0.05). The main EO compounds were subjected to a molecular docking investigation to look into how they interacted with target proteins in comparison with standard inhibitors physostigmine (AChE), ethacrynic acid (GST-1), and hexaconazole (CYP51). The chemical compounds of EOs were identified via GC-MS analysis. Based on GC-MS analysis β-pinene, cis -nerolidol, 2-heptyl acetate, and α-pinene were the major compounds identified in PLAO; while in VACAO viridiflorol, β-caryophyllene, and 5-(1-isopropenyl-4,5-dimethyl bicyclo [4.3.0]nonan-5-yl)-3-methyl-2-pentenol acetate were detected as main components. Similarly, 1,8-cineole, (E)-β-ocimene, α-terpinyl acetate, and (Z)-β-ocimene were identified as major compounds in VACAO. When three EOs of P. longum , V. negundo , and V. agnus-castus were mixed, pesticidal activity results revealed a high synergy. These results validate synergistic interactions amongst the studied essential oils, which may support sustainable agriculture when applied as natural products against pathogens. The molecular docking results showed good binding affinities and attributed the strongest inhibitory activity to 5-(1-isopropenyl-4,5-dimethyl bicyclo [4.3.0]nonan-5-yl)-3-methyl-2-pentenol acetate for all the target proteins. • Essential oils (EOs) from Vitex negundo L., Piper longum L., and Vitex agnus-castus L. were assessed. • Key compounds identified were α-pinene, β-pinene, β-caryophyllene, caryophyllene oxide. • EOs displayed notable dose-dependent nematicidal and antifungal activity. • Synergistic biological effects were observed on mixing the EOs. • Molecular docking revealed compound interactions with target proteins. [ABSTRACT FROM AUTHOR]