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Objective: phytochemical investigation of the ethyl acetate fraction (EAF) of 80% aqueous methanol extract (AME) of Dypsis leptocheilos leaves, in addition to evaluation of the antioxidant, cytotoxic and antimicrobial activities of the AME and EAF. Docking was used to predict and understand cytotoxicity of the isolated compounds. Methods: The ethyl acetate fraction (EAF) of Dypsis leptocheilos leaves was subjected to different chromatographic separation techniques. Structures of the isolated compounds were established by different spectroscopic techniques (1H/13C NMR). Antioxidant activity was evaluated by DPPH assay, while cytotoxicity was evaluated by MTT cell viability assay. Antimicrobial activity was evaluated by agar diffusion method. The docking study was conducted using Auto Dock Vina; the estrogen receptor (PDB 5t92) was used as a receptor for the docking. Results: Chromatographic separation techniques were led to the isolation of five phenolic compounds; these compounds were identified to be apigenin 8-C-β-D-glucopyranoside (Vitexin) (1), apigenin 6-C-β-D-glucopyranoside (Isovitexin) (2), luteolin 7-O-β-D-glucopyranoside (3), luteolin 8-C-β-D-glucopyranoside (Orientin) (4), luteolin 6-C-β-D-glucopyranoside (Isoorientin) (5). They were isolated and identified for the first time from this plant species. The AME and EAF showed moderate activity against Gram positive and Gram negatvie bacteria, while both of them showed similar and powerful antioxidant activity with SC50 = 12.8±0.56 µg/ml and SC50 = 17±0.77 µg/ml respectively, compared to ascorbic (reference drug) SC50 = 14.2±0.35 µg/ml. The EAF showed higher cytotoxic activity on the MCF-7 cells (human breast cancer cell line), with IC50 = 12.3 ± 1.82 µg/ml, compared to Vinblastine Sulfate (reference drug). All isolated compounds showed good binding affinity to the estrogen receptors existed in the MCF-7 cell. Conclusion: Five phenolic compounds were isolated for the first time from the EAF of Dypsis leptocheilos leaves. The AME and EAF extracts showed variable antioxidant, antimicrobial and cytotoxic activities.

Effective and precise eradication of Helicobacter pylori (H. pylori) is the most promising approach to avoid H. pylori-related gastrointestinal disorders. The present study was conducted to demonstrate the efficacy of the co-delivery of hesperidin (Hesp) and clarithromycin (CLR) in nanostructured lipid carriers (NLCs) against H. pylori. We have produced a new delivery system by combining bioflavonoid Hesp and CLR NLCs to address the failure in single antibiotic therapies. Briefly, a blend of solid lipid, liquid lipid, and surfactant was used. Homogeneous NLCs with all the formulations showed a nano size and surface-negative charge and presented high in vitro stability and slow release of the drug even after 24 h. Bioimaging studies by scanning electron microscopy, transmission electron microscopy, and imaging flow cytometry indicated that NLCs interacted with the membrane by adhering to the outer cell membrane and disrupted the membrane that resulted in the leakage of cytoplasmic contents. The prepared NLCs provide sustained and controlled drug release that can be used to increase the rate of H. pylori eradication.

A new abietane diterpene namely plectrabarbene (2), together with two known compounds: sugiol (1) and 11,14-dihydroxy-8,11,13-abietatrien-7-one (3) have been isolated from the aerial parts of Plectranthus barbatus Andr. (Labiatae). The structures of these compounds were determined by various spectral techniques (e.g., UV, IR, NMR, and FAB) and by comparison with the literature data. A molecular docking study of the isolated diterpenes (1&ndash, 3) was performed with AChE to gain an insight into their AChE inhibition mechanism. The results of docking experiments revealed that the all tested compounds showed binding affinity at the active site of AchE in comparison to donepezil.

Two new compounds calothphenone (1) and 6-methoxy kaempferol 3-O-(6″-E-p-coumaroyl)-β- d-glucopyranoside (6-methoxy tiliroside) (2) along with six known compounds viz gallic acid (3), methyl gallate (4), kaempferol 3-O-(6″-E-p-coumaroyl)-β-d-glucopyranoside (tiliroside) (5), castalagin (6), kaempferol (7) and quercetin (8) were isolated from the ethyl acetate fraction (EAF) of 80% aqueous methanol extract of Calothamnus quadrifidus aerial parts. Their structure was established based on different chemical and spectroscopic techniques (1H-/13C-NMR and 2D NMR). Antioxidant activity for EAF and compounds 1, 2 and 5 was evaluated using DPPH, superoxide radical and nitric oxide (NO) inhibition methods. EAF exhibited strong activity to inhibit DPPH, superoxide and NO radicals. Moreover, all tested compounds demonstrated a close high ability to inhibit superoxide and NO radicals in comparison to ascorbic acid, but they exerted lower activity towards DPPH radical.

Methanolic extracts of edible plants and seaweeds were tested for their inhibitory activity against Jack bean urease. Quercetin-4'-O-beta-D-glucopyranoside was isolated from Allium cepa as a urease inhibitor with an IC(50) value of 190 microM-. Quercetin and two quercetin glycosides, avicularin and guaijaverin, were isolated from Psidium guajava as urease inhibitors with respective IC(50) values of 80 microM-, 140 microM-, and 120 microM-.