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The aim of this study was to determine whether the inoculation of plant growth-promoting bacteria to plants, vegetated in soil irrigated with textile effluent, influences plant biomass production, and soil remediation. Three different plant species ( Acacia ampliceps, Eucalyptus camaldulensis, and Leucaena leucocephala) with and without bacterial inoculation were grown in soil irrigated with secondary treated textile wastewater for one year. An endophytic bacterium, Burkholderia sp. strain PsJN, possessing plant growth-promoting 1-aminocyclopropane-1-carboxylate deaminase activity was inoculated to plants. There was more plant biomass production (up to 12%) and contaminants removal (up to 29%) from soil with bacterial inoculation as compared to soil having non-inoculated plants. Enhanced plant growth and soil remediation activity are associated with the survival and colonization of the inoculated bacterium in the rhizosphere and endosphere of plants. The highest plant biomass production and contaminants removal from soil were observed in the treatment, in which A. ampliceps was inoculated with Burkholderia sp. strain PsJN. These results suggest that plant-bacteria partnerships can be applied to improve plant growth and soil remediation during the application of industrial effluent for plant biomass production in the arid regions. [ABSTRACT FROM AUTHOR]

Pseudomonas aeruginosa EBN-8 mutant rhamnolipids produced on waste oils were investigated using normal-phase thin layer chromatography and fast atom bombardment mass spectrometry. Negative ion mode mass spectra yielded [M - H]- ions and their fragment ions, which gave some indications on the sequence of rhamnolipid biosynthesis. Five rhamnolipid homologs [viz. RC10C10 (m/z 503), RC12C10 or RC10C12 (531), RRC10C8 or RRC8C10 (621), RRC10C10 (649) and RRC12C10 or RRC10C12 (677)] were detected in four rhamnolipid combinations under the different carbon sources. The prevalence of rhamnolipids was confirmed by Fourier transform infrared and one-dimensional proton nuclear magnetic resonance. We also observed some correlations between the tensioactive characteristics and structural chemistry of the rhamnolipid surfactants. [ABSTRACT FROM AUTHOR]

The article presents a cross-sectional study which determines whether occupational exposure to a complex mixture of pesticides is linked to the significant increase of DNA damage in farmers who are chronically exposed to pesticides in open fields. It utilized leucocytes from agriculture workers who were prone to pesticide exposure during the spraying season of cotton crop. It also gathered serum from the subjects for further analysis. It showed that there was a significant damage among exposed subjects wherein smokers have a higher risk. Furthermore, the chronic exposure to pesticides produced DNA damages among pesticide sprayers and suggested that certain monitoring should be done as preventive measures.

Pseudomonas pseudomallei EBN-10 strain, previously isolated from a local pharmaceutical industry's wastewater, was spontaneously adapted to higher p-nitrophenol (PNP) levels, which then was subjected to gamma ray-induced mutagenesis; the efficient isolates hence obtained were designated as EBN-11 and EBN-12, respectively. EBN-12 mutant strain could completely mineralize PNP (100 mg/L) on the minimal media in 24 h while, the parent strain utilized only 6% of it. Addition of glucose as co-substrate further increased the PNP degradation rate; however, phenol inclusion inhibited the degradation process. Ammonium sulphate was experienced as the best of the nitrogen sources used by EBN-12 mutant strain, while degrading PNP. [ABSTRACT FROM AUTHOR]

Production of a microbial surfactant was studied by growing Pseudomonas aeruginosa EBN-8 mutant on varying concentrations (on the basis of total sugars) of clarified blackstrap molasses as a sole carbon and energy source with or without auxiliary synthetic nitrogen source in 250 mL shake flasks. The progress of fermentation process was monitored by measuring the production of metabolites, and surface-active and emulsification properties of the cell-free culture broth. The biosurfactant was isolated from the supernatant by acid precipitation followed by solvent extraction. The amount of rhamnolipids produced was determined by the orcinol method. The highest dry cell biomass (1.67 g/L) and rhamnolipid (1.45 g/L) yields were observed, at 96 h of incubation on 2% total sugars-based molasses amended with sodium nitrate (at C:N, 20:1) with the product yield related to dry cell biomass (YP/X, g/g) of 0.869, specific product formation rate (V, h-1) of 0.295 and volumetric productivity rate (PV, g/L/h) of 0.015. The surface tension of this culture medium dropped to 28.0 from 50.0 mN/m. [ABSTRACT FROM AUTHOR]

Abstract: Natural unmodified rhamnolipids are thermally self-assembled into soft microtubules, which can produce gold nanoparticles onto themselves due to the presence of rhamnose sugar moieties at their surface. The loading of gold nanoparticles on composite microtubules can be controlled by varying the concentration of gold salt to rhamnolipid and the reaction temperature. The composite rhamnolipid–gold nanoparticle microtubules are then heat treated to produce porous gold microwire-like structures with fairly controlled nanostructured features, which may have interesting applications in catalysis, biosensing and electronics. [Copyright &y& Elsevier]

Latent fingerprints are made visible in a single step by in situ growth of gold nanoparticles on ridge patterns. The chemicals, among the essential components of human sweat, found responsible for the formation and assembly of gold nanoparticles are screened and used as ink to write invisible patterns, using common ball pen and inkjet printer, which are then developed by selectively growing gold nanoparticles by soaking them in gold salt solution.