154 research outputs found
Phytochemical Investigation of Egyptian Spinach Leaves, a Potential Source for Antileukemic Metabolites: In Vitro and In Silico Study
Spinacia oleracea L., Amaranthaceae, leaves cultivated in Egypt demonstrated a potential antileukemic activity against the chronic myeloid leukemia, K562 cell line. Thus, the aim of this study is to carry out a phytochemical investigation of S. oleracea leaves as well as the isolation of its antileukemic phytoconstituents. Phytochemical investigation of S. oleracea leaves resulted in the isolation of seventeen known compounds. The biological study revealed that compounds hexaprenol, phytol, and 18-[(1-oxohexadecyl) oxy]-9-octadecenoic acid exhibited a remarkable antiproliferative activity against K562 cells in vitro. A mechanistic in silico study showed that hexaprenol, phytol, and 18-[(1-oxohexadecyl) oxy]-9-octadecenoic acid exhibited a strong binding affinity towards topoisomerase (docking score −12.50, −9.19, and −13.29 kcal/mol, respectively), and showed as well a strong binding affinity towards Abl kinase (docking score −11.91, −9.35, and −12.59 kcal/mol, respectively). Molecular dynamics study revealed that 18-[(1-oxohexadecyl) oxy]-9-octadecenoic acid produced stable complexes with both topoisomerase and Abl kinase with RMSD values of 1.81 and 1.85 Å, respectively. As a result of our findings, we recommend more in vivo and preclinical studies to confirm the potential benefit of spinach leaves for chronic myeloid leukemia patients. Graphical Abstract: [Figure not available: see fulltext.
Improvement of Cell Wall Degrading Enzymes Production by Alginate Encapsulated Trichoderma spp.
Conidia of three Trichoderma isolates were formulated to make alginate pellets with or without 0.5 % chitin or dried fungal mycelium of Fusarium oxysporum as carbon source. The formulations were compared for their ability of in vitro chitinase and β-1,3-glucanase
production with free fungal spore suspensions. Conidia entrapped in alginate with or without adjuvant showed high production of enzymes (especially for chitinase) even when repeated 4 times. The addition of chitin or dried fungal mycelium as adjuvant enhanced the enzyme production up to 5 and 2-fold for chitinase and β-1,3-glucanase, respectively. Alginate concentration and surface area of the beads affected the enzyme production. The optimum initial pH, incubation time and temperature were pH=6, 12 days and 40 °C for chitinase, and pH=7, 10 days and 35 °C for β-1,3-glucanase production. The improvement of cell wall degrading enzyme production by alginate encapsulated Trichoderma could explain the in vivo inhibitory effect of such formulations on the target phytopathogenic fungi
CYTOTOXIC AND ANTIOXIDANT ACTIVITIES OF SECONDARY METABOLITES FROM PULICARIA UNDULATA
Objective: To evaluate the in vitro cytotoxicity, antioxidant activities and structure-activity relationship of secondary metabolites isolated from Pulicaria undulata.Methods: The methylene chloride-methanol (1:1) extract of the air-dried aerial parts of Pulicaria undulata was fractionated and separated to obtain the isolated compounds by different chromatographic techniques. Structures of the isolated compounds were determined on the basis of the extensive spectroscopic analysis, including 1D and 2D NMR and compared with the literature data. The crude extract and the isolated compounds were evaluated for in vitro antioxidant activity using the 2,2 diphenyl dipicryl hydrazine (DPPH) method and cytotoxic assay using human breast cancer (MCF-7) and hepatoma (Hep G2) cell line.Results: Nine secondary metabolites were isolated from Pulicaria undulata in this study. Of which two terpenoidal compounds; 8-epi-ivalbin and 11β, 13-dihydro-4H-xanthalongin 4-O-β-D-glucopyranoside firstly isolated from the genus pulicaria and three flavonoids; eupatolitin, 6-methoxykaempferol, and patulitrin firstly isolated from P. undulata. 6-methoxykaempferol (IC50 2.3 µg/ml) showed the most potent antioxidant activity. The highest cytotoxic effect against MCF-7 and Hep G2 cells was obtained with eupatolitin (IC50 27.6 and 23.5 µg/ml) respectively. The structure-activity relationship was also examined and the findings presented here showed that 3, 5, 7, 4' and 3, 5, 4', 5'-hydroxy flavonoids were potent antioxidant and has cytotoxic activity.Conclusion: Pulicaria undulata is a promising medicinal plant, and our study tends to support the therapeutic value of this plant as antioxidant drug and in the treatment of cancer
Antimicrobial resistance pattern and molecular epidemiology of ESBL and MBL producing Acinetobacter baumannii isolated from hospitals in Minia, Egypt
Introduction: Multidrug resistant (MDR) Acinetobacter baumanii (A. baumannii) strains have emerged as novel nosocomial pathogens threatening patients’ lives, especially in intensive-care units (ICUs). This study aims to determine the prevalence of carbapenemase genes and CTX-M-15 and the resistance pattern of carbapenemase producing isolates.
Methods: A total of 530 clinical specimens were collected from patients suffering from different infections, antibiotic susceptibility test was performed using kirby-bauer disk diffusion method. ESβL production was detected phenotypically by double-disc synergy test (DDST). Carbapenemase production was tested by Modified Hodge Test (MHT). Then, these isolates were tested for MBL detection by disc potentiation test. Carbapenemase encoding genes (VIM, IMP, GIM and SPM, OXA-51, OXA-23 and OXA-143) and CTX-M-15 were tested by polymerase chain reaction (PCR).
Results: Out of 530 samples, 20 bacterial isolates were identified as A. baumannii from different infectious cases, 35% of isolates were ESBL-producers. Eleven isolates were resistant to imipenem (4 isolates) and meropenem (7 isolates). All carbapenem resistant isolates were MHT positive. Nine (45%) isolates were confirmed as A. baumannii by OXA-51 (all were carbapenem resistant). Distribution of IMP, VIM, GIM and SPM, OXA-23, OXA-143 and CTX-M-15 by PCR were 55, 50, 50, 25, 35, 45 and 33% respectively.
Conclusion: The high prevalence of resistance genes and the resistance pattern of the isolates indicate that the detection of ESBLs and MBLs phenotypically and genotypically with the study of the resistance pattern of the isolates is critically important for the surveillance of drug resistance in the hospital environment
Effect of Benomyl on Chitinase and β-1,3-Glucanase Production by Free and Alginate Encapsulated Trichoderma harzianum
On PDA-benomyl plates growth of Trichoderma harzianum was inhibited by 20 and 30 % at benomyl 1 and 2 μg/mL, respectively, and was completely inhibited at 5 μg/mL. In minimal synthetic medium (MSM) amended with different concentrations of benomyl (1.0, 3.0, 5.0, 7.0 and 10.0 μg/mL), fungal immobilisation improved chitinase and β-1,3-glucanase production at low benomyl concentrations (1, 3 and 5 μg/mL). Further increase in the production of both enzymes was obtained by immobilisation at higher benomyl concentrations (7 and 10 μg/mL). Fungal immobilisation increased bound chitinase by 15- to 30-fold at 3 and 5 μg/mL benomyl concentration, respectively. However, no effect was obtained on the bound β-1,3-glucanase. Different benomyl concentrations (0.3 to 1500 μg/mL) had no significant inhibitory effect on the activities of free or immobilised chitinase and β-1,3-glucanase. It could be suggested that either immobilised Trichoderma or immobilised chitinase and β-1,3-glucanase could be used in combination with benomyl to control plant pathogens
<i>Garcinia cambogia</i> phenolics as potent anti-COVID-19 agents:phytochemical profiling, biological activities, and molecular docking
COVID-19 is a disease caused by the coronavirus SARS-CoV-2 and became a pandemic in a critically short time. Phenolic secondary metabolites attracted much attention from the pharmaceutical industries for their easily accessible natural sources and proven antiviral activity. In our mission, a metabolomics study of the Garcinia cambogia Roxb. fruit rind was performed using LC-HRESIMS to investigate its chemical profile, especially the polar aspects, followed by a detailed phytochemical analysis, which led to the isolation of eight known compounds. Using spectrometric techniques, the isolated compounds were identified as quercetin, amentoflavone, vitexin, rutin, naringin, catechin, p-coumaric, and gallic acids. The antiviral activities of the isolated compounds were investigated using two assays; the 3CL-Mpro enzyme showed that naringin had a potent effect with IC50 16.62 μg/mL, followed by catechin and gallic acid (IC50 26.2, 30.35 μg/mL, respectively), while the direct antiviral inhibition effect of naringin confirmed the potency with an EC50 of 0.0169 μM. To show the molecular interaction, in situ molecular docking was carried out using a COVID-19 protease enzyme. Both biological effects and docking studies showed the hydrophobic interactions with Gln 189 or Glu 166, per the predicated binding pose of the isolated naringin
The Grazemore Decision Support System for Grazing Management of Dairy Cows
Low prices of concentrates and the high demands for good management of grass growth associated with grazing, have led to lower utilisation of grazed grass in Europe. The use of decision support systems (DSS) with valid predictions of herbage growth (HG) and milk yield (MY) may improve grazing management for dairy farmers. The aim of this study was to explore the possibilities to improve grazing management of dairy cows in Europe, by developing a DSS within the European Union project, Grazemore
Bioassay-guided isolation, metabolic profiling, and docking studies of hyaluronidase inhibitors from Ravenala madagascariensis
Hyaluronidase enzyme (HAase) has a role in the dissolution or disintegration of hyaluronic acid (HA) and in maintaining the heathy state of skin. Bioassay-guided fractionation of Ravenala madagascariensis (Sonn.) organ extracts (leaf, flower, stem, and root) testing for hyaluronidase inhibition was performed followed by metabolic profiling using LC–HRMS. Additionally, a hyaluronidase docking study was achieved using Molecular Operating Environment (MOE). Results showed that the crude hydroalcoholic (70% EtOH) extract of the leaves as well as its n-butanol (n-BuOH) partition showed higher HAase activity with 64.3% inhibition. Metabolic analysis of R. madagascariensis resulted in the identification of 19 phenolic compounds ranging from different chemical classes (flavone glycosides, flavonol glycosides, and flavanol aglycones). Bioassay-guided purification of the leaf n-BuOH partition led to the isolation of seven compounds that were identified as narcissin, rutin, epiafzelechin, epicatechin, isorhamnetin 7-O-glucoside, kaempferol, and isorhamnetin-7-O-rutinoside. The docking study showed that narcissin, rutin, and quercetin 3-O-glucoside all interact with HAase through hydrogen bonding with the Asp111, Gln271, and/or Glu113 residues. Our results highlight Ravenala madagascariensis and its flavonoids as promising hyaluronidase inhibitors in natural cosmetology preparations for skin care
Chemical composition and therapeutic potential of three <i>Cycas</i> species in brain damage and pancreatitis provoked by gamma-radiation exposure in rats
Abl Kinase Inhibitors from Egyptian Spinach Leaves in the Treatment of Chronic Myeloid Leukemia
Presenter: Ospanov Meirambekhttps://egrove.olemiss.edu/pharm_annual_posters_2021/1013/thumbnail.jp
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