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The high surface area of mesoporous silica SBA-15 has been synthesized successfully by hydrothermal treatment with direct addition of PVA, triblock copolymer (P123) as a direct structure agent and tetraethyl orthosilicate (TEOS) as a precursor. The mesoporous silica SBA-15 have been characterized with nitrogen physisorption, scanning electron microscopy, Fourier transformed infrared spectroscopy, and x-ray diffraction. Measurement of nitrogen sorption indicated that with the addition of PVA, the surface area is increased but the pore volume and pore diameter is not significantly. The short time of hydrothermal treatment (20 h) and using x-ray diffraction, showed that the morphological structure of silica SBA-15 can be changed to a orthorhombic crystal system. The result of the FTIR and SEM-EDX characteristic indicated the functional groups and morphology of the SBA-15 with a narrow pore size distribution. The BET method has exhibited the largest surface area 1726 m2/g, pore volume 1.4 cm3/g, and pore diameter 3.2 nm. It can be suggested that the silica mesoporous SBA-15 will have potential application prospect in catalysis, storage, and adsorbent.

Moringa oleifera is a tropical plant in the Moringaceae family that contains a lot of bioactive compounds. This study aimed to isolate and characterize the enzyme xanthine oxidase (XO), and conducted inhibitory tests on XO using methanol extracts of M. oleifera leaves. The xanthine oxidase enzyme isolated from bovine milk was characterized to determine the optimum pH, temperature, and substrate concentration. XO inhibition was evaluated by in vitro and in silico methods. The results of XO isolation and characterization of bovine milk showed the optimum conditions at pH 6.5, substrate concentration of 0.1 mM, and temperature 35 °C with an activity rate of 32.47 mU/mL; 21.55 mU/mL, and 21.94 mU/mL. Inhibition analysis results on methanol extract of M. oleifera leaves showed the highest activity decrease at the extract concentration of 160 ppm, with a relative inhibition value of 21.35%, while allopurinol as a positive control has a relative value inhibition of 61.21%. Relative value inhibition indicated the potential of M. oleifera leaves as a source of medicinal plants for gout sufferers. Additionally, a computational analysis was performed to observe the molecular interaction between the primary compounds of M. oleifera leaves, i.e., 5-O-acetyl-thio-octyl-β-L-rhamnofuranoside, quinic acid, and 2-dimethyl(trimethylsilylmethyl)silyloxymethyltetrahydrofuran, and XO using the molecular docking method. The finding implied that these compounds are bound to the catalytic sites of XO by hydrogen bonds and hydrophobic interactions, indicating the primary compounds of M. oleifera leaves could become XO inhibitors to treat gout disease. [ABSTRACT FROM AUTHOR]

The Complex of Cu(II)cysteinedithiocarbamate has been synthesized, it was prepared by the “in situ method” and characterized by using Ultraviolet-Visible (UV-Vis), Infra-Red (IR) spectroscopy, X-Ray Fluorescence (XRF) instruments. While melting point and conductivity also measured. The presence of UV-Vis maximum spectrums of Cu(II)cysteinedithiocarbamate at 296 nm and 436 nm indicated that electronic transition π → π * dan n → π * of CS2 and N=C=S myotis. The presence of the wavelength in the region of 399-540 cm-1 of IR spectra is indicated that has been coordination occurred between Cu(II) with Sulphur (S), Nitrogen (N), and Oxygen(O) atoms respectively from cysteinedithiocarbamate ligands. The XRF data confirm the presence of Cu and S in the new compound formed. The XRD spectrums also showed several hkl of CuO, CuS, and CuN indicating there is an interaction between Cu(II) with N, S, and O atoms. Cytotoxic test of Cu(II)cysteinedithiocarbamate complex has IC50= 639,35 µg/mL which indicates that the complex can induce the morphological MCF-7 cancer cells changes towards apoptosis. [ABSTRACT FROM AUTHOR]

Silver nanoparticles have been synthesized by reduction method using extract of Muntingia calabura L. a bioreductor. The process of silver nanoparticles formation was monitored by UV-Vis method. The results showed that the absorbance values increased according to the increase of reaction time. Maximum absorption of silver nanoparticle was obtained at a wavelength of 41-421 nm. The size of silver nanoparticles was determined using a PSA (Particle Size Analyzer) with a particle size distribution of 97.04 nm. The functional groups compound that contribute in the synthesis was analyzed using Fourier Transform Infrared Spectroscopy (FTIR). Morphology of the silver nanoparticles was observed by an Scanning Electron Microscope instrument and the structure characterization of the compounds were analyzed using X-Ray Diffraction. The glucose nanosensor based on silver nanoparticles have the measurement range of 1 mM - 4 mM with the regretion (R2) is 0,9516, the detection limit of sensor is 3,2595 mM, the sensitivity of sensor is 2,0794 A. mM-1. mM-2. [ABSTRACT FROM AUTHOR]

MgO nanoparticle was synthesized by sol-gel method from magnesium acetate and oxalic acid dissolved in methanol followed by annealed process. Characterization of functional groups was performed using (FTIR) Fourier Transforms Infrared spectroscopy, crystal profile analysis using (XRD) X-ray Diffraction and morphology using (SEM) Scanning Electron Microscopy. The FTIR and XRD results indicated that the magnesium acetate converted into magnesium oxalate (Precursor), and then the anneal process was changed into MgO nanoparticles. The Scherrer's equation used to determine the distribution of MgO nanoparticle crystals. Modified Williamson-Hall plot is used to determine the strain, stress and energy density value (micro structural properties) based on angle values 2θ and (FWHM) Full width at half maximum of XRD angles from 10° to 80°. The results of the XRD and SEM analysis show that magnesium complexes have changed. The solid layer formed by the Mg polymer complex network is transformed into a cubic structure. [ABSTRACT FROM AUTHOR]

One of the plants with many functions as tradisional drug is Muntingia calabura L. leaves. It caused the leaves has high content of tannins, saponins and flavonoids. The presence of these compounds is great potential as bioreductor to produce gold nanoparticles (AuNPs). In this study has been done biosynthesis and characterization of AuNPs using the aqueus extract of Muntingia calabura L. leaves. The AuNPs obtained were characterized by UV-Visible spectra, Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). Based on the results of the bioreduction process of HAuCl4 into AuNPs can be known that the AuNPs are successfully produced with optimum time 5 hours. Surface Plasmon resonance synthesis of AuNPs was done at a wavelength of 543.4 nm. At wavelength 660 nm is known as Longitudinal Plasma Resonance characteristic of one of AuNPs crystal form that is Au-nanorod, triangular or hexagonal. The IR band analysis shows that there are three functional groups that play a role in bioreduction process of gold nanoparticle formation are C=O, C-N and -OH group. XRD difractogram showed that AuNPs is formed at 2θ = 37,82o (1 1 1), 44.05o (2 0 0), 64.43o (2 2 0) and 77.55o (3 1 1). The average crystal size using XRD analysis and PSA (Particles Size Analyzer) test are 36.93 nm and 78.2 nm respectively. The AuNPs crystals are mostly oriented (3 1 1) with an average crystal lattice length of 0.4 nm. [ABSTRACT FROM AUTHOR]