This study investigated the phytochemical profile and evaluated the antimicrobial and insecticidal properties of Eucalyptus camaldulensis Dehn. essential oil (EC-EO) from Algeria, using in vitro and in silico approaches. The yield of EC-EO was 0.27%, with gas chromatography-mass spectrometry (GC-MS) revealing spathulenol (58.24%), cryptone (17.22%), and o-cymene (15.53%) as the major compounds. EC-EO exhibited notable antibacterial activity, particularly against Salmonella typhimurium (14 ± 1.00 mm) and Staphylococcus aureus (14.5 ± 0.50 mm). It also showed effective antifungal activity against Penicillium sp. (11.5 ± 0.49 mm), Candida albicans (11.2 ± 0.29 mm), and Aspergillus fumigatus (9.8 ± 0.27 mm). Insecticidal assays against Tribolium castaneum were conducted using contact toxicity, fumigation toxicity, and repellent activity methods. The median lethal concentration (LC50) for contact toxicity was 0.011 μL/insect after 72 h, while the fumigation test had an LC50 of 122.29 μL/L air. Repellent activity tests showed percentage repellency (PR) values exceeding 80% after 6 h. The molecular geometry and electronic properties of the main compounds were studied using density functional theory (DFT) calculations. In addition, the interaction mode and binding affinity of these molecules with three key enzymes involved in antimicrobial activity, DNA gyrase, dihydrofolate reductase (DHFR) and Tyrosyl-tRNA synthetase (TyrRS), were explored by molecular docking.

This investigation aimed to assess the in vitro and in silico biological properties of the ethyl acetate (EtOAc) extract obtained from leaves of Rubus ulmifolius Schott collected in Algeria. The phytochemical screening data disclosed that flavonoids, tannins, coumarins, saponins, and anthocyanins were abundant. High levels of total phenolics, total flavonoids and flavonols (523.25 ± 3.53 µg GAE/mg, 20.41 ± 1.80, and 9.62 ± 0.51 µg QE/mg respectively) were detected. Furthermore, GC-MS analysis was performed to identify low molecular weight compounds. d-(-)-Fructofuranose, gallic acid, caffeic acid, and catechin were detected as main metabolites of the EtOAc extract. The outcomes revealed that the extract exerted a potent antioxidant apt, and ensured significant bacterial growth inhibitory capacity, where the inhibition zone diameters ranged from 20.0 ± 0.5 to 24.5 ± 0.3 mm. These outcomes were confirmed through molecular docking against key bacterial enzymes that revealed significant interactions and binding affinities. d-(-)-Fructofuranose was identified as the most polar and flexible compound. Gallic acid and caffeic acid demonstrated higher unsaturation. Caffeic acid was well absorbed in the blood–brain barrier (BBB) and human intestine. Catechin was well absorbed in CaCO₃, and can act as an inhibitor of CYP1A2. These results highlight how crucial it is to keep looking into natural substances in the quest for more potent and targeted pathology therapies.

This study investigated the phytochemical composition and biological activities of Myrtus communis essential oil (EO) from Algeria, focusing on its antimicrobial, antifungal, and insecticidal properties using in vitro and in silico approaches. Gas chromatography–mass spectrometry (GC-MS) analysis identified myrtenyl acetate (57.58%), 1,8-cineole (17.82%), and α-terpineol (6.82%) as the major constituents. M. communis EO exhibited significant antibacterial activity, particularly against Staphylococcus aureus (13.00 ± 0.70 mm) and Salmonella typhimurium (13.00 ± 1.50 mm), with moderate inhibition of Bacillus subtilis (10 ± 1.00 mm) and Escherichia coli (9.00 ± 0.70 mm), while Pseudomonas aeruginosa showed resistance. The antifungal activity was notable against Fusarium oxysporum (16.50 ± 0.50 mm), Aspergillus fumigatus (11.00 ± 1.00 mm), and Penicillium sp. (9.00 ± 0.60 mm) but ineffective against Aspergillus niger. Insecticidal activity against Tribolium castaneum was evaluated using contact toxicity, fumigation toxicity, and repellent activity assays. The EO demonstrated potent insecticidal effects, with an LC₅₀ value of 0.029 µL/insect for contact toxicity and 162.85 µL/L air for fumigation after 96 h. Additionally, the EO exhibited strong repellent activity, achieving 99.44% repellency at a concentration of 0.23 mg/cm² after 24 h. Density functional theory (DFT) calculations provided insights into the molecular geometry and electronic properties of the key bioactive compounds. Molecular docking studies evaluated their binding affinities to bacterial enzymes (DNA gyrase, dihydrofolate reductase6, and Gyrase B) and insecticidal targets (acetylcholinesterase), revealing strong interactions, particularly for geranyl acetate and methyleugenol. These findings highlight M. communis EO as a promising natural antimicrobial and insecticidal agent, with potential applications in plant protection and biopesticide development.