RAPID SYNTHESIS OF SILVER NANOPARTICLES USING AQUEOUS LEAF EXTRACT OF ACHYRANTHES ASPERA AND STUDY OF THEIR ANTIMICROBIAL AND FREE RADICAL SCAVENGING ACTIVITIES

Objective: To study the biosynthesis of silver nanoparticles (AgNPs) using the aqueous leaf extract of Achyranthes aspera and check the antimicrobial and free radical scavenging activity of the biosynthesized AgNPsMethods: 20 ml of aqueous leaf extract of A. aspera was added to 80 ml of 2 mM silver nitrate and the reaction solution was heated at 55-60 °C for 20 min and incubated. Biosynthesized AgNPs were characterized by different spectroscopic measurements including UV-Vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction pattern (XRD), Transmission electron microscopy (TEM) and Dynamic light scattering (DLS). Antimicrobial activity of AgNPs was checked against Staphylococcus aureus, Bacillus subtilis (Gram+ve bacteria), Klebsiella pneumonia, Pseudomonas aeruginosa (Gram-ve bacteria), Aspergillus niger, Candida albicans and Candida nonalbicans (Human pathogenic fungi) by employing disc diffusion method. The free radical scavenging activity of AgNPs was checked against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Hydrogen peroxide (H2O2) radicals. Results: After 1 h of incubation, the light yellow color of the reaction solution was turned to dark brown. UV-Vis spectra showed the absorption peak at 445 nm and confirmed the synthesis of AgNPs. FTIR spectra revealed the functional groups plausibly involved in the biosynthesis and stabilization of AgNPs. XRD pattern revealed that the synthesized AgNPs were crystalline in nature with face-centered cubic (FCC) phase. TEM revealed that the synthesized AgNPs were spherical in shape with 20-40 nm in size. DLS analysis revealed that the average size of AgNPs was 24.5 nm. Biosynthesized AgNPs were highly stable due to their high negative zeta potential value of-28.1 mV. AgNPs showed effective antimicrobial activity against S. aureus (16.4 mm), B. subtilis (14.5 mm), K. pneumonia (13.2 mm), P. aeruginosa (12.4 mm), A. niger (12.2 mm), C. albicans (11.5 mm) and C. nonalbicans (11.8 mm). AgNPs showed effective free radical scavenging activity with IC50 values of 77.73 and 90.53 µg/ml respectively against DPPH and H2O2 radicals.Conclusion: Successful and rapid synthesis of AgNPs was achieved using aqueous leaf extract of A. aspera. Biosynthesized AgNPs were proved to be excellent antimicrobial agents and free radical scavengers.Keywords: Achyranthes aspera, Silver nanoparticles, TEM, DLS, Antimicrobial and Radical scavenging activit

American ginseng suppresses inflammation and DNA damage associated with mouse colitis

Ulcerative colitis (UC) is a dynamic, idiopathic, chronic inflammatory condition associated with a high colon cancer risk. American ginseng has antioxidant properties and targets many of the players in inflammation. The aim of this study was to test whether American ginseng extract prevents and treats colitis. Colitis in mice was induced by the presence of 1% dextran sulfate sodium (DSS) in the drinking water or by 1% oxazolone rectally. American ginseng extract was mixed in the chow at levels consistent with that currently consumed by humans as a supplement (75 p.p.m., equivalent to 58 mg daily). To test prevention of colitis, American ginseng extract was given prior to colitis induction. To test treatment of colitis, American ginseng extract was given after the onset of colitis. In vitro studies were performed to examine mechanisms. Results indicate that American ginseng extract not only prevents but it also treats colitis. Inducible nitric oxide synthase and cyclooxygenase-2 (markers of inflammation) and p53 (induced by inflammatory stress) are also downregulated by American ginseng. Mucosal and DNA damage associated with colitis is at least in part a result of an oxidative burst from overactive leukocytes. We therefore tested the hypothesis that American ginseng extract can inhibit leukocyte activation and subsequent epithelial cell DNA damage in vitro and in vivo. Results are consistent with this hypothesis. The use of American ginseng extract represents a novel therapeutic approach for the prevention and treatment of UC

Análisis de las Estrategias Metodológicas implementadas por el docente en el desarrollo del proceso de enseñanza- aprendizaje en la disciplina de Geografía e Historia de Nicaragua y su Didáctica en los alumnos/as de Primer año “B” del turno regular de Formación Inicial Docente en la Escuela Normal Central de Managua Alesio Blandón Juárez durante el I semestre del Curso Escolar 2016

El presente trabajo de investigación tiene como finalidad analizar la efectividad que tienen las Estrategias Metodológicas implementadas por el docente en el desarrollo del proceso de enseñanza- aprendizaje en la disciplina de Geografía de Nicaragua y su Didáctica en los alumnos/as de Primer año “B” del turno regular de Formación Inicial Docente en la Escuela Normal Central de Managua Alesio Blandón Juárez durante el I semestre del Curso Escolar 2016. Dicho trabajo de investigación tiene un enfoque naturista o cualitativo, es una vía de transformación social, a través de la cual el ser humano descubre la realidad que le rodea, determina los medios y procedimientos para actuar sobre ella y transformarla de acuerdo a una intensión social. Los procesos de investigación cualitativa, tienen como finalidad primordial la generación y construcción de conocimientos que contribuyen al desarrollo social y personal de cada uno de los miembros de una comunidad. La fase de recolección de los datos de la investigación desarrollada, se realizó de dos formas: una información que se recogió mediante la observación directa del comportamiento de los informantes claves y una información que se obtuvo mediante la interrogación de algunos informantes claves. Para ello, primeramente el investigador realizo una inmersión en el campo de trabajo, con el propósito de identificar los lugares adecuados para recoger y producir la información necesaria y requerid

Synthesis, Characterization, and Antibacterial Activity of New Linezolid-Based Phosphoramidate Derivatives

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