Few studies thoroughly investigated different Yucca species introduced to Egypt. As a part of our ongoing investigation of the Yucca species; Yucca aloifolia and its variety Yucca aloifolia variegata, Yucca filamentosa, and Yucca elephantipes (Asparagaceae) were extensively subjected to phytochemical and antimicrobial investigation. Yucca species cultivated in Egypt showed no antimicrobial effect. GC/MS of the lipoid contents of Y. aloifolia variegata was carried out. Twenty-six fatty acids were identified. Saturated fatty acids established almost twice the unsaturated ones and constituted 64.64% of which palmitic acid and palmitoleic acid signifying 58.28% and 30.98%, respectively. Hydrocarbons were 21 constituting 39.64% of the unsaponifiable fraction. Only three sterols 42.36% were detected, major was γ-sitosterol. LC–MS/MS comparison of the 4 plant extracts imply that Y.aloifolia variegata L extract was the richest, which was apparent through its superior biological activity. LC–MS/MS analysis of the total alcoholic extract (Alc) of the leaves of Y.aloifolia variegata L. was performed using MS-techniques at different voltages; equal to 35 and 135 eV. Negative and positive-ion modes analyses at low fragmentation energy allowed the tentative identification of 41 and 34 compounds, respectively. The LC–ESI–MS/MS analysis in the positive mode proved to be better in the identification of saponins.

Mosquitoes are unquestionably the most medic arthropod vectors of disease. Culex pipiens, usually defined as a common house mosquito, is a well-known carrier of several virus diseases. Crude ethanol extracts of different organs of Agratum houstonianum are tested with Culex pipiens Linnaeus (Diptera: Culicidae) to determine their larvicidal, antifeedant, and repellency effects. Alongside biochemical analysis, the activity of the AChE, ATPase, CarE, and CYP-450 is detected in the total hemolymph of the C. pipiens larvae to examine the enzymatic action on the way to explain their neurotoxic effect and mode of action. Through HPLC and GC–MS analysis of the phytochemical profile of A. houstonianum aerial parts is identified. The larvicidal activity of aerial parts; flower (AF), leaf (AL), and stem (AS) of A. houstonianum extracts are evaluated against the 3rd instar larvae of C. pipiens at 24-, 48- and 72-post-treatment. A. houstonianium AF, AL, and AS extracts influenced the mortality of larvae with LC50 values 259.79, 266.85, and 306.86 ppm, respectively after 24 h of application. The potency of AF and AL extracts was 1.69- and 1.25-folds than that of AS extract, respectively. A high repellency percentage was obtained by AF extract 89.10% at a dose of 3.60 mg/cm². A. houstonianium AF prevailed inhibition on acetylcholinesterase and decrease in carboxylesterase activity. Moreover, a significant increase in the ATPase levels and a decrease in cytochrome P-450 monooxegenase activity (− 36.60%) are detected. HPLC analysis prevailed chlorogenic and rosmarinic acid as the major phenolic acids in AL and AF, respectively. GC–MS analysis of A. houstonianum results in the identification of phytol as the major makeup. Precocene I and II were detected in AF. Linoleic, linolenic, and oleic acid were detected in comparable amounts in the studied organs. Overall, results suggest that the A. houstonianum flower extract (AF) exhibits significant repellent, antifeedant, and larvicidal activities.

Compared to its leaf, few studies have been reported on the seeds of Moringa oleifera Lam. Metabolites profiling analysis of M. oleifera seed methanolic extract (ME) and its fixed oil (MO) was attempted via LC/MS and GC/MS. LC/MS analysis of M. oleifera seeds annotated 84 peaks of which glucosinolates and their corresponding acetyl isomers were abundant. GC/MS of seed oil revealed the abundance of fatty acids with oleic acid at 34.3%. ME exhibited significant anti-Helicobacter pylori activity with MIC₅₀ 0.92 µg/mL, nearly one-half that of Clarithromycin. Fixed oil (MO) showed a nonselective anti-inflammatory effect with IC₅₀= 24.4 ± 0.8 µg/mL correlated to Ibuprofen. To unravel the mechanism of the anti-H. pylori activity a molecular docking study of the principal components of the ME has been performed, using H. pylori urease enzyme. Interactions with Ni²⁺ ions and amino acid residue in the active site, which are crucial for the enzyme's biochemical role, are evidenced. Graphical Abstract

Mosquitoes and mosquito-borne infectious diseases are a global challenge, especially with increased resistance to synthetic insecticides. The foregoing study aimed to utilize the essential oil of leaves of Citrus sinensis var. Valencia as a cheap, safe, eco-friendly (green), and effective alternative to chemical insecticides. Essential oil samples were collected from fresh and dried leaves across different seasons. They are subjected to hydrodistillation and then GC analysis to be compared. Seventy-seven compounds were detected in all samples where monoterpene hydrocarbons represented the most abundant class of hydrocarbons in fresh leaves (52.6–74.4%) and dried leaves (58.6–66.9%). Sabinene (8.26–29.2%), delta-3-carene (8.23–16.4%), D-limonene (2.50–11.2%), and β-myrcene (2.40–4.93%) were the major monoterpene hydrocarbons in all seasons. Oxygenated monoterpenes comprising β-linalool, citronellal, terpinen-4-ol, β-citral, and α-citral exhibited also appreciable percentages in fresh (21.2–43.4%) and dried leaves (23.4–33.0%). Hierarchical cluster analysis (HCA) and principal component analysis (PCA) effectively segregated all samples into three discriminate clusters where, β-linalool, terpinen-4-ol, β-elemene enantiomer, sabinene, and β-phellandrene constitute the main discriminatory biomarkers. Essential oil of fresh spring leaves (FS) was chosen for nano-formulation adopting the hot emulsification method. Both FS sample and the prepared nano-hexosomal formula were screened against the 3rd instar larvae Culex pipiens L. (common house mosquito). LC₅₀ and LC₉₅ values of FS and oil loaded nano-formula were (48 and 30 552 mg L⁻¹) and (30 and 1830 mg L⁻¹) respectively. α-Citral followed by citronellal showed the best fitting within the binding sites of acetylcholine esterase enzyme utilizing molecular docking. Thus, it can be concluded that Valencia orange leaf as a nano-formulation could serve as an effective and sustainable insecticidal agent.

The essential oils of Ageratum houstonianum Mill grown in Egypt were obtained and studied for the first time. The essential oils of leaves (0.1 % v/w) and flowers (0.06 % v/w) of A. houstonianum Mill. (Asteraceae) were comparatively analyzed by GC/MS using non polar column Rtx-5MS. A total of 11-32 components were identified, 7 being common in both samples. The main constituents of both leaves-and flowers-derived oil samples were precocene I (22.4-34.6 %), β-caryophyllene (63.9-13.7 %), and precocene II (10.8-29.6 %) respectively. The principle difference was a considerably more pronounced sesquiterpenes presence in the leaves-oil, amounting to 65.8 %, than in the flowers counterpart (32.4 %). Caryophyllene (63.9 %) was the major sesquiterpenes detected in leaves-oil, while flowers-oil showed less amounts of sesquiterpenoid hydrocarbons (32.4 %) and represented by caryophyllene (13.5 %). Chromenes was prevailed major constituents of flowers derived oil (64.8 %) nearly double its percent in the leaves derived oil (33.3 %). In vitro screen of antimicrobial and cytotoxic activities was determined against positive control. No antifungal activity was experiential on the tested fungi for all tested samples in the used concentration. Flowers-oil sample is being mostly efficient as antibacterial against Bacillus subtilis and Staphylococcus aureus with potency 50 % compared to gentamicin. The essential oil samples revealed marked in vitro cytotoxicity against colon (HCT-116) carcinoma cell line with IC₅₀ (11.1 %, 14.2 %) μg/ml for the leaves-, flowers-derived oil sample, respectively. The antibacterial effect of the essential oil of the flowers of A.houstonianum Mill can be credited to chromenes. As well as the leaves derived oil prevailed caryophyllene as a major constituents which may justify its observed cytotoxic activity.