Antibacterial and antibiofilm effects of silver nanoparticles against the uropathogen Escherichia coli U12.

The drug-resistant bacterial strains' emergence increases day by day. This may be a result of biofilm presence, which protects bacteria from antimicrobial agents. Thus, new approaches must be used to control biofilm-related infections in healthcare settings. In such a study, biological silver nanoparticles were introduced in such a study as an anti-biofilm agent against multidrug-resistant E. coli U12 on urinary catheters. Seven different silver nanoparticles concentrations were tested for their antimicrobial activities. Also, anti-biofilm activities against E. coli U12 were tested. Using the dilution method, the silver nanoparticles concentration of 85 µg/ml was the MIC (Minimum Inhibitory Concentration) that had excellent biocompatibility and showed significant antibacterial activity against E. coli U12. Scanning electron microscopy (SEM) confirmed that the highest efficient dose of silver nanoparticles was 340 µg/ml at 144 h that reduced adhesion of E. coli U12 to the urinary catheter. E. coli U12 cells ruptured cell walls and cell membranes after being examined using transmission electron microscopy (TEM). Thus, biologically prepared silver nanoparticles could be used to coat medical devices since it is effective and promising to inhibit biofilm formation by impregnating urinary catheters with silver nanoparticles.

Design and synthesis of novel phthalocyanines as potential antioxidant and antitumor agents starting with new synthesized phthalonitrile derivatives.

New phthalonitrile derivatives formed from reactions of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) were considered as the key intermediates for the synthesis of new phthalocyanines. Moreover, new phthalonitrile derivatives 2, 5, 9, 10, 15 and 16 reacted with 1,4-diazabicyclo[2.2.2]octane (DBO) or hydroquinone to afford the corresponding new phthalocyanine dyes 3, 6, 11, 12, 17 and 18. In addition, the cyclotetramerization of phthalic anhydride derivative 20 afforded new phthalocyanine dye 22. Spectral and elemental investigations revealed the structures of the newly synthesized phthalocyanines. The antioxidant and cytotoxic properties of the novel compounds were investigated, and it has been established that compounds 17 and 18 have very strong anticancer and antioxidant action against all cell lines.

Synthesis of novel cyanine dyes as antitumor agents.

In this study, some novel cyanine dyes, 1, 3, and 5-15, were synthesized by a one-pot step reaction of pyridinium salts 2 and/or 4 with benzenaminium salt 1. N-{[1-Chloro-3,4-dihydronaphthalen-2-yl)methylene]benzenaminium} chloride 1 was obtained by the reaction of α-tetralone with Vilsmeier-Haack reagent, followed by a mixture of an equimolar ratio of anilin/ethanol (1:1). All new cyanine dyes were evaluated in vitro for their anticancer activity against two cell lines, that is, HepG2 (human hepatocellular liver carcinoma) and MCF-7 (breast cancer). The obtained results were compared with human lung fibroblasts (WI-38) and Vero cells (derived from the kidney of an African green monkey) as normal cells. In particular, some of these compounds, 6, 9, 13, and 14, were found to be the most potent derivatives against all the cancer cell lines, without effect on the normal cells. According to the structure-activity relationship, compound 13 (IC50 = 8.8 µg/ml) exhibited a higher activity against HepG2 cells, as it contains the azo group and two phenyl rings and due to the presence of the π-conjugated system attached to the two pyridine rings. Compound 6 (IC50 = 8 µg/ml) exhibited a higher activity against MCF-7 cells, as it contains two chlorine atoms and the π-conjugated system of the pyridine rings.

Green Synthesis of Zinc Oxide Nanoparticles Using Aqueous Extract of Deverra tortuosa and their Cytotoxic Activities.

In recent years, there is a growing interest towards the green synthesis of metal nanoparticles, particularly from plants; however, yet no published study on the synthesis of ZnO.NPs using the Deverra tortuosa extract. Through this study, zinc oxide nanoparticles (ZnO.NPs) have been synthesized based on using the environmentally benign extract of the aerial parts of D. tortuosa as a reducing and capping agent. ZnO.NPs synthesis was confirmed using UV-Visible (UV-Vis) spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD) and High Resolution-Transmission Electron Microscope (HR-TEM). The qualitative and quantitative analyses of plant extract were done. The potential anticancer activity was in vitro investigated against two cancer cell lines (human colon adenocarcinoma "Caco-2" and human lung adenocarcinoma "A549") compared to their activities on the human lung fibroblast cell line (WI38) using the MTT assay. Both the aqueous extract and ZnO.NPs showed a remarkable selective cytotoxicity against the two examined cancer cell lines.

New cytotoxic flavonoids from aerial parts of Platycladus orientalis L.

Investigation of Platycladus orientalis yielded five flavonoids, including aglycone flavone 1 (apigenin), flavone glycoside 2 (apigenin 7-O-ß-D-glucopyranoside), new gernaylated flavone glycoside 3 (apigenin 8-gernayl-4'-O-α-gluco pyranoside) and two new pernylated flavonoid glycosides 4 & 5 (apigenin 8-pernyl-4'-glucopyranosyl-7-O-α-glucopyranoside and apigenin 5-pernyl-7-glucopyranosyl-4'-O-ß-D-glucopyranoside). Their structures were elucidated on the basis of spectroscopic evidence. The cytotoxicity of compounds 1-5 were tested against Lung adenocarcinoma (A549), human hepatocellular liver carcinoma (HepG2), human breast carcinoma (MCF-7) cell lines and mouse fibroblast cell line NIH/3T3 as normal cells. This assay gave spot on structure activity relationship which, showed that cytotoxicity of compounds (1) and (2) against three cell lines was weak as IC50 > 15. Compounds (4) and (5) had moderate cytotoxic and no toxic effect on normal cell. Compound (3) showed high cytotoxic activity against tested three cell lines with no toxic effect of normal cells.[Formula: see text].

Three new coumarin types from aerial parts of Ammi majus L. and their cytotoxic activity.

Three new coumarin types were isolated from the aerial parts of the wild medicinal plant Ammi majus, which was collected from western Asia (Saudi Arabia), including pyrano coumarin, namely, 5-isobutylcoumarin-6-C-glucoside (1); furanocoumarin, namely, 6,7,9-Trimethoxy-3-(8'-methoxy-2'-oxo-2H-chromen-3-yl)-2H-furo[3,2-g]chromen-2(3H)-one (2); and pyrone coumarin, namely, 6-hydroxy-3-(2-hydroxypropyl)-7-methoxy-4 methyl coumarin (3). The structures were determined by spectroscopic methods, mainly 1D- and 2D-NMR. In vitro cytotoxicity was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-tetrazolium bromide (MTT) assay. The results of cytotoxicity depending on their structure features showed that compound 3 had high activity on different cell lines, while compound 1 showed no activity against HCT116. Compound 2 had high activity towards HCT116 cell line.

A new isoflavonoid from seeds of Lepidium sativum L. and its protective effect on hepatotoxicity induced by paracetamol in male rats.

A new isoflavonoid, 5,6-dimethoxy-2',3'-methylenedioxy-7-C-ß-d-gluco-pyranosyl isoflavone was isolated from the seeds of Lepidium sativum L. along with two known isoflavonoids, 7-hydroxy-4',5,6-trimethoxyisoflavone and 7-hydroxy-5,6-dimethoxy-2',3'-methylenedioxyisoflavone. The structures of all compounds were elucidated with NMR spectrometry. Compounds 1, 2 and the new isoflavonoid 3 were evaluated for their ability to reduce the hepatotoxicity induced by paracetamol in male rats by reducing the damage and toxicity effects on liver cells with a significant improvement of total antioxidant capacity, normalizing the levels of liver enzymes GSH, SOD, GPX, CAT and GST compared to control group.

Fremy's salt-mediated oxidative addition. A new approach in the total synthesis of naturally dipetalolactone and its immunomodulatory activity.

The structure of the natural dipyranocoumarin dipetalolactone has been confirmed by an unambiguous synthetic route from resorcinol. This sequence was initiated by a pyran ring formation step which introduced the 3-chloro-3-methylbut-1-yne moiety. Then, the expected product undergoes a Fremy's salt-meditated oxidative addition followed by ring closure to yield dipetalolactone. Dipetalolactone was also found to have immunological activity in a mouse carcinoma S180-bearing mice cell line.

Anti-inflammatory new coumarin from the Ammi majus L.

Investigation of the aerial parts of the Egyptian medicinal plant Ammi majus L. led to isolation of new coumarin, 6-hydroxy-7-methoxy-4 methyl coumarin (2) and 6-hydroxy-7-methoxy coumarin (3); this is the first time they have been isolated from this plant. The structures of the compounds (2 &3) were elucidated by spectroscopic data interpretation and showed anti-inflammatory and anti-viral activity. GRAPHICAL An efficient, one-new coumarin (2) was isolated from the aerial parts of the A. Majus L. was evaluated for their anti-viral and anti-inflammatory activities.