Exploration of microwaves for biorefining of phenolic antioxidants from Citrus reticulata peels: spectrophotometric and spectroscopic analysis

Ever since the introduction of glutaraldehyde as a fixative in electron microscopy of biological specimens, the identification of impurities and consequently their effects on biologic ultrastructure have been under investigation. Several reports postulate that the impurities of glutaraldehyde, used as a fixative, are glutaric acid, glutaraldehyde polymer, acrolein and glutaraldoxime.Analysis of commercially available biological or technical grade glutaraldehyde revealed two major impurity components, none of which has been reported. The first compound is a colorless, water-soluble liquid with a boiling point of 42°C at 16 mm. Utilizing Nuclear Magnetic Resonance (NMR) spectroscopic analysis, this compound has been identified to be — dihydro-2-ethoxy 2H-pyran. This impurity component of the glutaraldehyde biological or technical grades has an UV absorption peak at 235nm. The second compound is a white amorphous solid which is insoluble in water and has a melting point of 80-82°C. Initial chemical analysis indicates that this compound is an aldol condensation product(s) of glutaraldehyde.

Download Full-text

Elemental analysis of human erythrocytes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015318x ◽

1989 ◽

Vol 47 ◽

pp. 242-243

Author(s):

S. A. Livesey ◽

A. A. del Campo ◽

E. S. Griffey ◽

D. Ohlmer ◽

T. Schifani ◽

...

Keyword(s):

Sample Preparation ◽

Elemental Analysis ◽

Human Erythrocyte ◽

Spectroscopic Analysis ◽

Model System ◽

Human Erythrocytes ◽

List Type ◽

Chemical Fixation ◽

Ethanol Dehydration ◽

Lowicryl K4m

The aim of this study is to compare methods of sample preparation for elemental analysis. The model system which is used is the human erythrocyte. Energy dispersive spectroscopic analysis has been previously reported for cryofixed and cryosectioned erythrocytes. Such work represents the reference point for this study. The use of plastic embedded samples for elemental analysis has also been documented. The work which is presented here is based on human erythrocytes which have been either chemically fixed and embedded or cryofixed and subsequently processed by a variety of techniques which culminated in plastic embedded samples.Heparinized and washed erythrocytes were prepared by the following methods for this study :(1). Chemical fixation in 4% paraformaldehyde/0.25% glutaraldehyde/0.2 M sucrose in 0.1 M Na cacodylate, pH 7.3 for 30 min, followed by ethanol dehydration, infiltration and embedding in Lowicryl K4M at -20° C.

Download Full-text

Antimicrobial and cytotoxic activity of Macrophomina phaseolina isolated from gummosis infected citrus reticulata

Chittagong University Journal of Biological Sciences ◽

10.3329/cujbs.v5i1.13378 ◽

2013 ◽

pp. 125-133

Author(s):

Rubal C Das ◽

Rajib Banik ◽

Robiul Hasan Bhuiyan ◽

Md Golam Kabir

Keyword(s):

Escherichia Coli ◽

Staphylococcus Aureus ◽

Brine Shrimp ◽

Inhibitory Concentration ◽

Lethal Dose ◽

Macrophomina Phaseolina ◽

Chloroform Extract ◽

Citrus Reticulata ◽

Gram Negative Bacteria ◽

Gram Negative

Macrophomina phaseolina is one of the pathogenic organisms of gummosis disease of orange tree (Citrus reticulata). The pathogen was identified from the observation of their colony size, shape, colour, mycelium, conidiophore, conidia, hyaline, spore, and appressoria in the PDA culture. The crude chloroform extracts from the organism showed antibacterial activity against a number of Gram positive and Gram-negative bacteria. The crude chloroform extract also showed promising antifungal activity against three species of the genus Aspergillus. The minimum inhibitory concentration (MIC) of the crude chloroform extract from M. phaseolina against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, and Shigella sonnie were 128 ?gm, 256 ?gm, 128 ?gm and 64 ?gm/ml respectively. The LD50 (lethal dose) values of the cytotoxicity assay over brine shrimp of the crude chloroform extract from M. phaseolina was found to be 51.79 ?gm/ml. DOI: http://dx.doi.org/10.3329/cujbs.v5i1.13378 The Chittagong Univ. J. B. Sci.,Vol. 5(1 &2):125-133, 2010

Download Full-text

Chromatographic and spectroscopic analysis of the fluorescent compounds derived from monosaccharides on HPTLC-NH2plates

JPC - Journal of Planar Chromatography - Modern TLC ◽

10.1556/jpc.15.2002.6.11 ◽

2002 ◽

Vol 15 (6) ◽

pp. 449-453 ◽

Cited By ~ 5

Author(s):

G. Grygierczyk ◽

Walter Fischer ◽

M. Sajewicz ◽

P. Kuś ◽

R. Wrzalik ◽

...

Keyword(s):

Spectroscopic Analysis ◽

Fluorescent Compounds

Download Full-text

A Peptoid with Extended Shape in Water

10.26434/chemrxiv.7552139 ◽

2019 ◽

Author(s):

Jumpei Morimoto ◽

Yasuhiro Fukuda ◽

Takumu Watanabe ◽

Daisuke Kuroda ◽

Kouhei Tsumoto ◽

...

Keyword(s):

Spectroscopic Analysis ◽

Dimensional Space ◽

Three Dimensional ◽

Biomolecular Recognition ◽

Biological Application ◽

New Class ◽

Proteolytic Resistance ◽

Pharmacokinetic Properties ◽

Optically Pure ◽

Three Dimensional Space

<div> <div> <div> <p>“Peptoids” was proposed, over decades ago, as a term describing analogs of peptides that exhibit better physicochemical and pharmacokinetic properties than peptides. Oligo-(N-substituted glycines) (oligo-NSG) was previously proposed as a peptoid due to its high proteolytic resistance and membrane permeability. However, oligo-NSG is conformationally flexible and is difficult to achieve a defined shape in water. This conformational flexibility is severely limiting biological application of oligo-NSG. Here, we propose oligo-(N-substituted alanines) (oligo-NSA) as a new peptoid that forms a defined shape in water. A synthetic method established in this study enabled the first isolation and conformational study of optically pure oligo-NSA. Computational simulations, crystallographic studies and spectroscopic analysis demonstrated the well-defined extended shape of oligo-NSA realized by backbone steric effects. The new class of peptoid achieves the constrained conformation without any assistance of N-substituents and serves as an ideal scaffold for displaying functional groups in well-defined three-dimensional space, which leads to effective biomolecular recognition. </p> </div> </div> </div>

Download Full-text