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This exhaustive in silico study looks into the molecular interactions of phthalates and their metabolites with human peroxisome proliferator-activated receptor (hPPAR) and retinoid X receptor (hRXR) ?, ? and ? subtypes - the nuclear receptor proteins function as transcription factors by regulating the expression of downstream genes. Apart from the much discussed plasticizer bisphenol A, we examined the binding affinities of 15 common diphthalates and their monophthalates, natural (linoleic acid, conjugated linoleic acid) and synthetic (bezafibrate, pioglitazone, GW 50156) ligands with hPPARs. In addition to these phthalates, specific natural (retinoic and phytanic acids) and synthetic (bexarotene, rosiglitazone) ligands were examined with hRXRs. The Maestro, Schr�dinger Suite 2012 was used for the molecular docking study. In general, natural ligands of hPPAR showed less binding efficiencies than phthalic acid esters and drugs. The diphthalate di-iso-decyl phthalate showed the highest G score (-9.99) with hPPAR (?), while its monophthalate (mono-iso-decyl phthalate) showed a comparatively less G score (-9.56). Though the PPAR modulator GW 50156 showed strong affinity with all hPPAR subtypes, its highest G score (-12.43) was with hPPAR?. Hazardous di(2-ethylhexyl)phthalate generally showed a greater preference to hRXRs than hPPARs, but its highest G score (-10.87) was with hRXR?, while its monophthalate (Mono(2-ethylhexyl)phthalate) showed a lesser G score (-8.59). The drug bexarotene showed the highest G score (-13.32) with hRXR?. Moreover, bisphenol A showed more affinity towards hRXR. Briefly, this study gives an overview on the preference of phthalic acid esters, natural and synthetic ligands on to hPPAR and hRXR subtypes, which would lead to further in vitro mechanistic as well as in vivo preclinical and clinical studies. � 2013 John Wiley & Sons, Ltd.

A series of norephedrine-based Schiff bases (1a-6a and 1b-6b) were synthesized by reacting substituted salicylaldehydes with d-norephedrine or l-norephedrine. The structure of these compounds was confirmed by elemental analyses and spectroscopic techniques. The molecular structures of 5a and 6a have been determined by X-ray crystallography, which revealed that the compounds are in the oxoamino form, with bent intramolecular N-H���O (N���O?2.58�) hydrogen bonds and that they are associated in dimers bridged by linear intermolecular O-H���O (O���O?2.69�) hydrogen bonds. The density functional theory calculations on 5a confirmed that the oxoamino form is more stable than the phenolimino form by 12.2kcal/mol. All the compounds were evaluated for their antibacterial activity using resazurin dye as indicator by twofold dilution method against four bacteria namely, Bacillus subtilis (NCIM2718), Staphylococcus aureus (NCIM5021), Escherichia coli (NCIM2931), and Proteus vulgaris (NCIM2813). � 2011 John Wiley & Sons A/S.

Escherichia coli is used for eco-friendly extra cellular synthesis of metallic silver and gold nanoparticles. This is achieved by reducing AgNO 3 and HAuCl 4 solutions respectively under ambient conditions by using the extra cellular protein produced by the microorganism. The proteins act as reducing as well as capping agent. The nanoparticles were characterized by UV-Visible spectroscopy, X-Ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR) and transmission electron microscopy (TEM). Both the nanoparticles are polydisperse. Gold particles predominantly exhibit flat and plate like morphology. These nanoparticles are stable in water for more than three months. The silver nanoparticles are able to inhibit the growth of several Gram positive and negative microorganisms, and the gold nanoparticles exhibit good antioxidant activity. This approach is simple, does not use toxic chemicals and is amenable for large scale commercial production. Copyright � 2012 American Scientific Publishers All rights reserved.

Twenty new quinoxalines bearing azetidinone and thiazolidinone groups were synthesized by cyclocondensation of Schiff bases of quinoxaline-2, 3-dione and were characterized with several analytical tools. They were tested against Mycobacterium tuberculosis H37Rv at a concentration of 10?g/mL by Microplate Alamar Blue Assay method. Quinoxaline derivatives with 2-chloro, dimethylamino and nitro substitutions exhibited in vitro activity, comparable to that of the drug, isoniazid. Three-dimensional quantitative structure-activity relationship studies indicated that electrostatic and steric field descriptors could explain the observed activity. The developed model fits the data well and has good predictive capability (r 2= 0.81, q 2= 0.71, F=27.06, r 2_pred = 0.84, r 2 m = 0.84, r 2 BS=0.80). Electronegative groups play an important role in the antitubercular activity. � 2011 John Wiley & Sons A/S.

Some of the wastewater treatment technologies commonly used in the chemical industry are compared. Primary treatment technologies are less expensive than secondary and tertiary processes and are designed to handle large volumes of dilute effluent and include physical and chemical treatments. The purpose of secondary treatment is to remove soluble and colloidal organics, and suspended solids that have survived the primary treatment process. Tertiary treatment is carried out after secondary treatment to remove significant amounts of nitrogen, phosphorus, heavy metals, biodegradable organics, bacteria, and viruses. The physical tertiary treatment systems include low-pressure microfiltration and ultrafiltration, and the membranes used in this method act as physical barriers to prevent contaminants from passing through. A futuristic disinfection method, which combine photons and nanostructures, require a better understanding of the mechanisms that control the interaction of pathogens with excited photocatalyst surfaces and active moieties, such as hydroxyl radicals and superoxides.

Novel sixteen chalcones and thirteen 1,3,5-triphenyl-2-pyrazolines were synthesized and characterized using FT-IR, HR-Mass, NMR (1H-NMR, 13C-NMR, 135 DEPT, 1H-1H CoSY and 1H and 13C CoSY) and XRD. These compounds were evaluated for their antibacterial activity against six micro-organisms, namely Bacillus subtilis NCIM 2718, Staphylococcus aureus NCIM 5021, Salmonella typhi NCIM 2501, Enterobacter aerogenes NCIM 5139, Pseudomonas aeruginosa NCIM 5029, and Proteus vulgaris NCIM 2813 by twofold dilution method using resazurin as the indicator dye. In the case of chalcones, compounds with hydroxyl and bromo substitutions in the B-ring favor activity and benzyloxy substitution irrespective of its position in the A-ring. In the case of 1,3,5-triphenyl-2-pyrazolines, chloro substitution in the A-ring favors activity. Hydrophilic/lipophilic balance of the compounds plays a major role in their antibacterial activity. � 2010 John Wiley & Sons A/S.

Aims: To isolate and characterize the biosurfactant-producing micro-organism from petroleum-contaminated soil as well as to determine the biochemical properties of the biosurfactant. Methods and Results: A novel rhamnolipid-producing Pseudomonas aeruginosa (GenBank accession number) strain was isolated from a petroleum-contaminated soil. Surface active compound was separated by solvent extraction of the acidified culture supernatant. The extract was able to reduce the surface tension of water from 72 to 44 mN m -1 at a critical micelle concentration of 11�27 � 1�85 mg l-1. It showed better activity (based on microdilution method) against Gram-positive (? 31 mg ml-1) bacteria and filamentous fungi (? 50 mg ml-1) than Gram-negative bacteria (? 125 mg ml-1) with mild toxicity (HC50-38 � 8�22 ?g ml-1) to red blood cells. Fourier transform infrared spectroscopy revealed the presence of aliphatic chain, hydroxyl groups, ester and glycosidic bonds. Presence of nineteen rhamnolipid homologues with variation in chain length and saturation was revealed from liquid chromatography coupled to mass spectrometry with electrospray ionization. Conclusion: The results indicate that the isolated biosurfactant has a novel combination of rhamnolipid congeners with unique properties. Significance and Impact of the Study: This study provides a biosurfactant, which can be used as a biocontrol agent against phytopathogens (Fusarium proliferatum NCIM 1105 and Aspergillus niger NCIM 596) and exploited for biomedical applications. � 2010 The Society for Applied Microbiology.

Quantitative structure activity relationships (QSAR) were developed relating the 14th and 21st day antituberculosis activity against H37Rv strain of Mycobacterium tuberculi and antibacterial activity against Staphylococcus aureus ATCC3750, Bacillus subtilis 6633, Escherichia coli ATCC3750, and Salmonella typhi NCTC786 of 55 pyrazine containing thiazolines and thiazolidinones, with the molecular descriptors. The developed models were able to fit the data well (r2 = 0.69-0.87) and had reasonable predictive capability (q2 > 0.62). The data were also divided into a training set and a test set, the former was used to develop the QSAR and the latter was used to evaluate the predictive capability of these developed models. In all the cases, the models were able to predict the test data set reasonably well. Predominantly, pyrazine ring is well-known for its antimycobacterial activity and hence these equation could be used to design newer analogues with higher activity. These compounds also possess both antitubercular and antibacterial activity. Descriptors pertaining to electronic, topology, and hydrophobicity of the molecules appear in the model equations. � 2008 The Authors.

The advantages and disadvantages and the and design parameters that need to be considered when selecting microreactors to achieve process intensification (PI) are discussed. Oscillatory flow mixing (OFM) reactor, which includes oscillation of fluids using an external oscillator, is characterized by plug-flow RTD, high heat transfer, and short reaction times. A plate-type reactor combines the high-heat-transfer capabilities of plate heat exchangers with the mixing of microreactors into a single unit, and is designed such that reactants can be injected at different locations along the flow path. The spinning tube-in-a-tube (STT) reactor is capable of creating sub-Kolmogoroff and near-Kolmogoroff eddies, which can reduce reaction time. The spinning disc reactor (SDR) has a very small reactor holdup, such that very hazardous reactions can also be carried out.

Biolgical treatment methods offer several advantages over the chemical and physical processes for removing volatile organic compounds (VOC) from the air. The advantages of biotreatment include lower operating and capital costs, removal of VOCs without the production of toxic byproducts, and its ability to operate at ambient temperature without the need for high-temperature regeneration steps. Biological methods for treating VOCs include the use of biofilters, biotrickling filters, bioscrubbers, suspended growth reactors, and membrane bioreactors. Several biological treatment processes use a fixed biofilm which is a structured community of bacterial cells enclosed in a self-produced, polymeric matrix and attached to an inert or living surface. It is important to combine more than one treatment procedure as biological systems can fail during sudden peaks in loading.