Enhancement of Sophorolipid Production of Wickerhamiella domercqiae var. sophorolipid CGMCC 1576 by Low-Energy Ion Beam Implantation

To meet the increasing demands of sophorolipids as biosurfactants and bioactive compounds, it is necessary to obtain higher and more specific sophorolipid-producing strains. One sophorolipid-producing strain, Wickerhamiella domercqiae var. sophorolipid CGMCC 1576 (Y_2A), was mutated by low-energy nitrogen ion beam implantation. Eighteen mutants produced 20?% more sophorolipids than the wild strain, and one mutant, N3-18, produced the highest yield of sophorolipids, 104?g/l, in a shaking flask, which increased by 84.71?% than the wild strain, and further elevated to 135?g/l in a 5-l bioreactor. High performance liquid chromatography analysis showed that the composition of every sophorolipid mixture from different strains was similar, while the contents of most components from mutants were higher than that from the wild strain. Two mutants, N1-32 and N3-18, produced more acidic sophorolipid components; three lactonic sophorolipid molecules with good anticancer activities were greatly enhanced in several mutants, especially monoacetylated lactonic sophorolipid with a C18 monounsaturated fatty acid, which were enhanced by 153 and 211?% in strains N1-32 and N3-18. Low-energy nitrogen ion beam implantation was efficient for obtaining a variety of high and specific sophorolipid-producing mutants to be applied in food, cosmetic, environmental, and pharmaceutical sectors.     

Surface morphology and biological activity of protein thin films produced by electrospray deposition

Protein thin films were prepared by the electrospray deposition (ESD) method from aqueous solutions of alpha-lactalbumin (alpha-LA) at different concentrations, and their surface morphologies and biological activities were characterized. The surface morphologies of the deposited films were observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The SEM and AFM images showed that the film surfaces had a fine porous structure, in which the pore diameters ranged from 40 to 600 nm. The biological activities of the cross-linked protein films were tested by the mechanochemical method. The response to calcium ion (Ca(2+)) demonstrated that the biological activity of the films was preserved. These results indicate that the ESD method is potentially useful for the fabrication of active protein thin films. The freestanding protein thin films prepared by ESD and postdeposition cross-linking provide novel options for protein-based biomaterials.     

Surface characterization and depth profiling of biological molecules by electrospray droplet impact/SIMS

Electrospray droplet impact (EDI) was applied to the analysis of peptides. The etching rate of bradykinin was estimated to be ~2 nm/min. This value is about one order of magnitude greater than the etching rate for SiO₂ (0.2 nm/min). Considering that the etching rate of argon cluster ions Ar₇₀₀⁺ for organic compounds is more than two orders of magnitude larger than that for inorganic materials, the rather small difference in etching rates of EDI for organic and inorganic materials is unique. When water/ethanol (1/1, vol%) solution of gramicidin S and arginine was dried in air, [gramicidin S + H]⁺ was observed as a predominant signal with little [Arg + H]⁺ right after the EDI irradiation, indicating that EDI is capable of detecting the analytes enriched on the sample surface. Copyright © 2011 John Wiley & Sons, Ltd.     

Synthesis and biological activity evaluation of new thiazolidinone-diclofenac hybrid molecules

Abstract

A novel series of [2-(2,6-dichlorophenylamino)-phenyl]-acetic acid N`-3-(substituted)-4-thiazolidin-5-ylidenemethyl-hydrazide derivatives has been designed and synthesized. The structures of synthesized compounds were confirmed by their <sup>1</sup>H NMR, <sup>13</sup>C NMR and LCMS spectroscopic data. Target compounds were screened for their in vitro anticancer activity according to US NCI protocols, in vitro trypanocidal activity toward Trypanosoma brucei brucei (Tbb) and evaluated for anti-inflammatory activity on the carrageenan edema model in rats. Biological screening data led to identification of compounds 3.3 ([2-(2,6-dichloro-phenylamino)-phenyl]-acetic acid N`-(4-oxo-2-thioxo-thiazolidin-5-ylidenemethyl)-hydrazide) and 3.7 ([2-(2,6-dichloro-phenylamino)-phenyl]-acetic acid N`-(4-oxo-2-thioxo-3-(3-trifluoromethylphenyl)thiazolidin-5-ylidenemethyl)-hydrazide) which demonstrated moderate antitumor activity on the non-small-cell lung cancer NCI-H522 and colon cancer HCT-116 cell lines. Several hit compounds (3.2, 3.4) exhibited the promising and significant inhibition growth of the parasites at micromolar concentrations (IC₅₀ values of 4.8 and 7.06?μM, respectively). The synthesized compounds also demonstrated considerable anti-inflammatory effect comparable to the reference non-steroidal anti-inflammatory drugs (NSAIDs) diclofenac sodium or ketorolac tromethamine.     

Two polyene amides produced by genetically modified Streptomyces diastaticus var. 108

Streptomyces diastaticus var. 108, a newly isolated strain, was recently characterized as a producer of two polyene macrolide antibiotics (rimocidin and CE-108), and the biosynthetic gene cluster was partially characterized. When the producer strain was genetically modified by transformation with some engineered SCP2*-derived vectors carrying the ermE gene, two previously uncharacterized macrolides were detected in the fermentation broth of the recombinant strain and chemically characterized as the amides of the parental polyene carboxylic acids. The biological activity and some in vitro toxicity assays showed that this chemical modification resulted in pharmaceuticals with improved biological properties compared with the parental products.     

A new antibacterial compound produced by an indigenous marine bacteria--fermentation, isolation, and biological activity

The use of microorganisms for biological purpose has become an effective alternative to control pathogens. A marine bacterium Pseudomonas aeruginosa was isolated from Eal fish of Baluchistan coast of Pakistan. This strain produced a bactericidal antibiotic against environmental and clinical isolates. In this study, we purified bactericidal antibiotic from the ethyl acetate extract of the cells of P. aeruginosa and analyzed its chemical structure. Based on spectrometric analysis, this compound 1 is proposed to be 1-methyl-1,4 dihydroquinoline and is active against methicillin-resistant Staphylococcus aureus (MRSA), methicillin-sensitive S. aureus (MSSA), Salmonella typhi, Shigella flexneri, Escherichia coli, Proteus mirabilis, Vibrio aliginolyticus, Micrococcus luteus, Enterococcus faecalis, Enterobacter faecium but it is not active against G streptococci, Candida albicans, Aspergillus niger. Minimal inhibitory concentration for Gram-positive bacteria was between 50 and 75 microg mL(-1) and for Gram-negative bacteria 75-100 microg mL(-1).     

Chemical constituents and biological activities of Dianthus elegans var. elegans

Chemical investigation of the aerial parts of Dianthus elegans var. elegans afforded two previously undescribed saponins, named dianosides M-N (1–2), together with four oleanane-type triterpenoid glycosides (3–6). Their structures were elucidated as 3-O-α-L-arabinofuranosyl-16α-hydroxyolean-12-ene-23α, 28β-dioic acid (1) and 3-O-α-L-arabinofuranosyl-(1 → 3)-β-D-glucopyranosyl 16α-hydroxyolean-12-ene-23α-oic acid, 28-O-β-D-glucopyranosyl-(1 → 6)-β-D-glycosyl ester (2) by chemical and extensive spectroscopic methods including IR, 1D, 2D NMR and HRESIMS. Both of the saponins were evaluated for their cytotoxicities against HEK-293, A-549 and HeLa human cancer cells using the MTT method. All compounds showed no substantial cytotoxic activity against tested cell lines. However, dianosides M-N and the n-butanol fraction exhibited considerable haemolysis in human erythrocyte cells. The immunomodulatory properties of dianosides M-N were also evaluated in activated whole blood cells by PMA plus ionomycin. Dianosides M-N increased IL-1β concentration significantly whereas the n-butanol fraction slightly augmented IL-1β secretion. All compounds did not change IL-2 and IFN-γ levels considerably.     

Morpholines. Synthesis and biological activity

The review analyzes methods of synthesis of 1,4-oxazines (morpholines) starting from vicinal amino alcohols and their derivatives, oxiranes, and aziridines. Examples of using morpholines in medicinal and organic chemistry as catalysts, auxiliaries, biologically active substances, and building blocks for their preparation are considered. The data published until February 2013 have been covered.     

Flexsim-X: a method for the detection of molecules with similar biological activity

We describe the development of the method Flexsim-X, which can be used to detect molecules with similar biological activity. This procedure is based on comparing virtual affinity fingerprints made up from docking scores of the molecules with respect to a reference set of binding sites. Using a test data set consisting of ligands from five different activity classes and randomly chosen compounds, the reference panel of binding sites was optimized in terms of size and composition. Systematic approaches as well as genetic algorithm based (GA) optimization procedures have been evaluated. Additionally, the effectiveness of the method is illustrated.     

Surface immobilization of indometacin for preparing polypropylene materials exhibiting biological activity

Russian Journal of Applied Chemistry - A procedure was proposed for the modification of the manganese-oxide catalyst hopcalite GFG allowing the new quality, water resistance of granules, to be...     

Directional states of symmetric-top molecules produced by combined static and radiative electric fields

We show that combined electrostatic and radiative fields can greatly amplify the directional properties, such as axis orientation and alignment, of symmetric top molecules. In our computational study, we consider all four symmetry combinations of the prolate and oblate inertia and polarizability tensors, as well as the collinear and perpendicular (or tilted) geometries of the two fields. In, respectively, the collinear or perpendicular fields, the oblate or prolate polarizability interaction due to the radiative field forces the permanent dipole into alignment with the static field. Two mechanisms are found to be responsible for the amplification of the molecules' orientation, which ensues once the static field is turned on: (a) permanent-dipole coupling of the opposite-parity tunneling doublets created by the oblate polarizability interaction in collinear static and radiative fields and (b) hybridization of the opposite parity states via the polarizability interaction and their coupling by the permanent dipole interaction to the collinear or perpendicular static field. In perpendicular fields, the oblate polarizability interaction, along with the loss of cylindrical symmetry, is found to preclude the wrong-way orientation, causing all states to become high-field seeking with respect to the static field. The adiabatic labels of the states in the tilted fields depend on the adiabatic path taken through the parameter space comprised of the permanent and induced-dipole interaction parameters and the tilt angle between the two field vectors.     

Monoterpenoids dithiophosphates. Synthesis and biological activity

O,O-Dialkyldithiophosphoric acids adds at the double bond of the racemic camphene and (+)- limonene in the presence of Lewis acids in accordance with the Markownikoff rule with the formation of Sterpenyl esters of dithiophosphoric acids. The reaction with camphene is accompanied by the rearrangement of camphane structure to that of bornane. Addition of dithiophosphoric acid to (+)-limonene proceeds with the participation of the exocyclic double bond. Toxic and genotoxic properties of the monoterpenoid dithiophosphates were studied.     

Permeabilization of biological and artificial membranes by a bacterial dirhamnolipid produced by Pseudomonas aeruginosa

Pseudomonas aeruginosa, when cultured under the appropriate conditions, secretes rhamnolipids to the external medium. These glycolipids constitute one of the most interesting classes of biosurfactants so far. A dirhamnolipid fraction was isolated and purified from the crude biosurfactant, and its action on model and biological membranes was studied. Dirhamnolipid induced leakage of internal contents, as measured by the release of carboxyfluorescein, in phosphatidylcholine unilamellar vesicles, at concentrations below its CMC. Membrane solubilization was not observed within this concentration range. The presence of inverted cone-shaped lipids in the membrane, namely lysophosphatidylcholine, accelerated leakage, whereas cone-shaped lipids, like phosphatidylethanolamine, decreased leakage rate. Increasing concentrations of cholesterol protected the membrane against dirhamnolipid-induced leakage, which was totally abolished by the presence of 50 mol% of the sterol. Dirhamnolipid caused hemolysis of human erythrocytes through a lytic mechanism, as shown by the similar rates of K⁺ and hemoglobin leakage, and by the absence of effect of osmotic protectants. Scanning electron microscopy showed that the addition of the biosurfactant changed the usual disc shape of erythrocytes into that of spheroechinocytes. The results are discussed within the frame of the biological actions of dirhamnolipid, and the possible future applications of this biosurfactant.     

Structure, stereochemistry, and biological activity of integramycin, a novel hexacyclic natural product produced by Actinoplanes sp. that inhibits HIV-1 integrase

[structure: see text] HIV-1 integrase is a critical enzyme for viral replication, and its inhibition is an emerging target for potential antiviral chemotherapy. We have discovered a novel inhibitor, integramycin, from screening of fermentation extracts using an in vitro assay. Integramycin possesses a hexacyclic ring system and exhibited an IC50 value of 4 microM against HIV-1 integrase (strand transfer). The isolation, structure elucidation, stereochemistry, conformation, and biological activity has been described.     

Surface clusters of colloid particles produced by deposition on sites

The possibility of producing surface clusters of well-defined structure formed by colloid particles was analyzed theoretically and experimentally. Theoretical results were derived by performing Monte Carlo-type simulations according to the generalized random sequential adsorption (RSA) mechanism. In these simulations, the jamming coverage of particles adsorbing irreversibly on spherical sites was determined as a function of the particle-to-site size ratio lambda. It was revealed that, by properly choosing lambda, a targeted site coordination can be achieved; for example, there can be one, two, three, and so forth particles attached to one site. The structure of the heterogeneous clusters produced in this way was described in terms of the pair correlation function. It was predicted that the extent of ordering within surface clusters was diminished as the concentration of sites increased. These theoretical predictions were checked by performing deposition experiments of negatively charged polystyrene latex particles (average diameter 0.9 mum) under the diffusion-controlled transport regime. Mica sheets precovered by positively charged polystyrene latex (average diameters 0.45 and 0.95 microm) were used as the substrate surface in these experiments. Positive latex (site) deposition was also carried out under diffusion-controlled transport conditions. The concentration of the sites and the adsorbed particles was determined by direct particle counting using optical microscopy. It was found, in quantitative agreement with theoretical simulations, that the structure of surface clusters produced in this way exhibits a significant degree of short-range ordering. It also was proven experimentally that clusters containing a targeted number of colloid particles (e.g., 2 and 4) could be produced by the deposition procedure.     

Surface analysis of films and film systems produced by pulsed laser deposition

Ceramic films and film systems (ZrO₂ films, ZrO₂/Ti multilayers, and BN films) are deposited by pulsed laser deposition (PLD) and analyzed using X-ray photoelectron (XPS), Auger electron (AES), and micro-Raman spectroscopies. The electron spectroscopies are used to determine the film stoichiometry, the nature of the bonding, and to specify contaminant species. The micro-Raman spectroscopy gives information on crystal structure, grain size, and mechanical stress within the films. In ZrO₂ films a stoichiometry is achieved with typically 5%, with only weak dependencies on processing variables. The only contaminants are a small amount of water from the ambient gas and a carbonaceous surface layer. Multilayers consisting of alternating ZrO₂ and Ti layers exhibit a TiC contamination within the Ti layers. Depending on the processing variables, BN films may be nearly stoichiometric or may have significant, even dominant contaminations throughout the film from elemental B, B₂O₃, and/or a boron-oxynitride species. The first component is due to the non-stoichiometric material removal from the target (N-depletion) at low laser fluences, as confirmed by XPS measurements on irradiated targets. The second and third arise from H₂O in the ambient, and exhibit a complex dependence on processing variables. Micro-Raman spectra show only amorphous or hexagonalphase BN. Depending on the position on the substrate relative to the laser-induced vapour/plasma plume, there may be a particle deposition or mechanical stress within the films, as evidenced from large shifts (up to 15 cm^–1) of the Raman spectral peaks.