Green and Rapid Synthesis of Anticancerous Silver Nanoparticles by Saccharomyces boulardii and Insight into Mechanism of Nanoparticle Synthesis

Rapidly developing field of nanobiotechnology dealing with metallic nanoparticle (MNP) synthesis is primarily lacking control over size, shape, dispersity, yield, and reaction time. Present work describes an ecofriendly method for the synthesis of silver nanoparticles (AgNPs) by cell free extract (CFE) of Saccharomyces boulardii. Parameters such as culture age (stationary phase growth), cell mass concentration (400 mg/mL), temperature (35°C), and reaction time (4 h), have been optimized to exercise a control over the yield of nanoparticles and their properties. Nanoparticle (NP) formation was confirmed by UV-Vis spectroscopy, elemental composition by EDX (energy dispersive X-rays) analysis, and size and shape by transmission electron microscopy. Synthesized nanoparticles had the size range of 3–10 nm with high negative zeta potential (−31 mV) indicating excellent stability. Role of proteins/peptides in NP formation and their stability were also elucidated. Finally, anticancer activity of silver nanoparticles as compared to silver ions was determined on breast cancer cell lines

Free Radical Scavenging and Antioxidant Activity of Silver Nanoparticles Synthesized from Flower Extract of Rhododendron dauricum

A simple and efficient eco-friendly approach for the biosynthesis of stable, monodisperse silver nanoparticles (AgNPs) using Rhododendron dauricum flower extract is described. Different reaction parameters (concentration of plant extract, substrate concentration, pH, temperature and reaction time) were optimized to synthesize AgNPs with controlled properties. AgNPs were characterized in terms of synthesis, size distribution (PDI of 0.25), capping functionalities (phenolic compounds) and microscopic evaluation by UV-Visible spectroscopy, dynamic light scattering, Fourier Transform Infrared (FTIR) spectroscopy and Transmission Electron Microscope (TEM). The specific characteristics and loss of organic content (1.81 mg) of the synthesized nanoparticles was measured by Differential Scanning Calorimetry (DSC) and Thermo Gravimetric Analysis (TGA). The results showed the simplistic and feasible approach for obtaining stable aqueous monodispersive AgNPs. Further, the antioxidant activity of AgNPs imparted by plant phenolic components was evaluated using DPPH assay and found to be comparable to standard TROLOX

Exploring the effects of processing methods on telmisartan-phospholipid complex: A comparative study

Drug-phospholipid complexes have emerged as potential drug delivery systems for poorly soluble drugs. The purpose of this study was to investigate the effect of processing methods on the physicochemical and biopharmaceutical performance of the telmisartan-phospholipid complex. In this study, telmisartan-phospholipid complexes were prepared using solvent evaporation (TELPLC-SE), freeze-drying (TELPLC-FD), and spray drying (TELPLC-SD) methods and subjected to a comparative investigation of solid-state characteristics (FTIR, DSC, and PXRD analysis), solubility, dissolution profiles, particle size, zeta potential, particle morphology (SEM analysis) and pharmacokinetic studies. The solvent evaporation method was found to be associated with the most significant FTIR peak shift/shape change, highest solubility advantage (TELPLC-SE 8.98 ± 1.08 µg/mL, TELPLC-SD 6.98 ± 1.38 µg/mL, TELPLC-FD 7.95 ± 1.02 µg/mL), maximum in-vitro drug release (TELPLC-SE 87.81 ± 4.64%, TELPLC-FD 84.71 ± 4.84 %, TELPLC-SD 79.93 ± 3.54 %) and highest peak plasma concentration (Cmax) of telmisartan (TELPLC-SE Cmax: 2.40 ± 1.34 µg/mL, TELPLC-SD Cmax: 2.20 ± 1.1 µg/mL, TELPLC-FD Cmax: 1.4 ± 1.3 µg/mL) whereas freeze-drying method was linked to the highest depression in melting point endotherm and spray drying method was associated to the maximum reduction in XRD peak intensity, the largest particle size and the lowest zeta potential. This study definitively answers the questions regarding the effect of processing methods on the telmisartan-phospholipid complex. Further studies are needed to explore the effect of process and formulation parameters

Development and validation of HPLC method for the resolution of derivatives of 1-bromo-3-chloro-2-propanol: a novel chiral building block for the synthesis of pharmaceutically important compounds

The methods for the separation of racemic compounds [(RS)-1-bromo-3-chloro-2-propanol, (RS)-1-bromo-3-chloropropan-2-yl acetate] into the corresponding enantiomers were tried to develop in high performance liquid chromatography in a single injection mode. In the case of HPLC, both the reversed (Phenomenex Lux 5u cellulose-1, Lux 5u cellulose-2, Lux 5u amylose-1) and normal phase (Chiralcel OJH, ODH, ADH) chiral columns were used for this purpose. HPLC methods could not resolute the desired enantiomers. However, phenoxy derivatives of (RS)-1-bromo-3-chloro-2-propanol and (RS)-1-bromo-3-chloro- propan-2-yl acetate were separated by normal phase (ODH) column using a mobile phase consisting of n-hexane and isopropanol (80: 20) at a flow rate of 0.5 mL/min (25°C) and detected at 254 nm. The method was validated for linearity, range, accuracy and precision. The developed method was applied for monitoring the progress of lipase catalyzed enantioselective synthesis of (S)-1-bromo-3-chloropropan-2-yl acetate from (RS)-1-bromo-3-chloro-2-propanol. All the analytes were synthesized chemically

Determination of gibberellins in fermentation broth produced by Fusarium verticilliodes MTCC 156 by high-performance liquid chromatography tandem mass spectrometry

A method for the detection of gibberellins produced by Fusarium verticilliodes is described using HPLCMS/MS (HPLC tandem MS). A Hypersil (5 μm) octadecylsilane column with methanol/water as eluent in the ratio 3:1 at a flow rate of 0.5 ml/min was used. In the HPLCMS, GA<SUB>3</SUB> (gibberellic acid; m/z 346.3) eluted at retention time t<SUB>r</SUB>=3.08 min, with the corresponding mass chromatogram having peaks at m/z 346.7 and 328.8 corresponding to the M<SUP>+</SUP> and M<SUP>+</SUP>-H<SUB>2</SUB>O ions respectively. The ethyl acetate extract from the broth, subjected to HPLCMS analysis under similar conditions, showed a constituent with t<SUB>r</SUB>=2.13 min, the mass chromatogram of which exhibited peaks at m/z 348.9 and 331.9 corresponding to the MH<SUP>+</SUP> and MH<SUP>+</SUP> -H<SUB>2</SUB>O ions respectively. Comparison of the MS and MS/MS results (direct infusion) of an authentic sample of GA<SUB>3</SUB> and the ethyl acetate extract from the broth revealed the formation of reduced GA<SUB>3</SUB> in the broth. The present study, utilizing HPLCMS/MS, describes an improved methodology for the unambiguous determination and estimation of gibberellins from fermentation broth

Use of response surface method for maximizing the production of arginine deiminase by Pseudomonas putida

Statistically designed experiments were used to optimize the production of arginine deiminase (ADI) by Pseudomonas putida KT2440 in batch culture. A Plackett-Burman design involving eleven factors showed that ADI production was most influenced by the initial pH and the initial concentrations of glucose and yeast extract. A central composite experimental design showed that the optimal values of these factors were 8.0, 10 g/L and 12.5 g/L, respectively. The other components of the optimal culture medium were bacto peptone 7.5 g/L, Triton X–100 0.30% (v/v), and arginine 3 g/L, for a culture temperature of 25 °C. Compared with the basal medium, the ADI activity in the optimized medium had nearly 4.5-fold increase (4.31 U/mL). The optimized medium was then used for a further study of ADI production in a 14 L stirred tank bioreactor. The agitation speed and the aeration rates were varied to determine suitable values of these variables

New chemo-enzymatic synthesis of (R)-1-chloro-3-(piperidin-1-yl) propan-2-ol

The present study deals with the efficient chemo-enzymatic synthesis of enantiopure (R)-1-chloro-3-(piperidin-1-yl) propan-2-ol 3, as an intermediate for (R)-arimoclomol. This intermediate was synthesized from racemic alcohol (RS)-3 using lipases with vinylacetate as the acyl donor in three different ionic liquids (1-butyl-3-methyl imidazolium tetrafluoroborate [BMIM][BF4], 1-butyl-3-methyl imidazolium hexafluorophosphate [BMIM][PF6], and 1-ethyl-3-methyl imidazolium tetrafluoroborate [EMIM][BF4]) in combination with an organic solvent (toluene). Various reaction parameters, such as temperature, time, substrate and enzyme concentration, and reaction medium (organic solvent and ionic liquid) were optimized using Pseudomonas aeruginosa MTCC 5113 lipases (PAL). It was observed that 30 mM of (RS)-3 and 30 mg/mL of PAL in 4 mL of solvent (toluene:[BMIM][BF4]::70:30) using vinyl acetate as the acyl donor at 30 °C gave good conversion (C = 50.02%) and enantiomeric excess (eeP = 98.91% and eeS = 99%) in 18 h. The (S)-1-chloro-3-(piperidin-1-yl) propan-2-yl acetate 4 and (R)-3 were separated by flash chromatography. Compound (R)-3 is a key intermediate for the synthesis of enantiopure arimoclomol and bimoclomol

Differential Molecular Interactions of Telmisartan: Molecular-Level Insights from Spectral and Computational Studies

In this study, we investigated differential molecular interactions of crystalline and amorphous forms of telmisartan (TEL), which is a non-peptide angiotensin-II receptor antagonist commonly used in the management of hypertension. Amorphous telmisartan (AM-TEL) was prepared using quench cooling of the melt. The analysis of solid-state properties of AM-TEL using differential scanning calorimetry (DSC) and X-ray powder diffraction (XRD) confirmed formation of AM-TEL. Based on a comparative analysis of molecular interactions using spectral (FTIR and 13C solid-state NMR) and computational tools, we demonstrated that amorphous telmisartan shows altered molecular interactions. Molecular dynamics simulation of amorphous and crystalline forms demonstrate that the amorphous form retained some of the molecular interactions in its disordered molecular arrangement, with a relatively stronger (decrease in bond length) but lesser (up to only 2.6 % of the population) hydrogen bonding network as compared with the crystalline counterpart (up to 76% of the population