Search results for "SOLUBILIZATION"

The endophytic microbiota of Citrus limon is transmitted from seed to shoot highlighting differences of bacterial and fungal community structures

2021

AbstractCitrus limon (L.) Burm. F. is an important evergreen fruit crop whose rhizosphere and phyllosphere microbiota  have been characterized, while seed microbiota is still unknown. Bacterial and fungal endophytes were isolated from C. limon surface-sterilized seeds. The isolated fungi—belonging to Aspergillus, Quambalaria and Bjerkandera genera—and bacteria—belonging to Staphylococcus genus—were characterized for indoleacetic acid production and phosphate solubilization. Next Generation Sequencing based approaches were then used to characterize the endophytic bacterial and fungal microbiota structures of surface-sterilized C. limon seeds and of shoots obtained under aseptic conditions fr…

Conversion of the sensor kinase DcuS ofEscherichia coliof the DcuB/DcuS sensor complex to the C4-dicarboxylate responsive form by the transporter DcuB

2016

Summary The sensor kinase DcuS of Escherichia coli co-operates under aerobic conditions with the C4-dicarboxylate transporter DctA to form the DctA/DcuS sensor complex. Under anaerobic conditions C4-dicarboxylate transport in fumarate respiration is catalyzed by C4-dicarboxylate/fumarate antiporter DcuB. (i) DcuB interacted with DcuS as demonstrated by a bacterial two-hybrid system (BACTH) and by co-chromatography of the solubilized membrane-proteins (mHPINE assay). (ii) In the DcuB/DcuS complex only DcuS served as the sensor since mutations in the substrate site of DcuS changed substrate specificity of sensing, and substrates maleate or 3-nitropropionate induced DcuS response without affec…

Analytical methods for the characterization and determination of nonionic surfactants in cosmetics and environmental matrices

2013

Nonionic synthetic surfactants, constituted of an assortment of classes, are common ingredients of industrial, household and body-care products. Alone or in combination with anionic surfactants, they perform a variety of functions including cleaning action, emulsification, skin conditioning, appearance and consistency modification, solubilization and dispersing agents. By far fatty alcohol ethoxylates (AEs) and alkylphenol ethoxylates (APEs) are more extensively used than any other nonionic surfactant class; however, works appearing in the literature making reference to the analysis of other nonionic surfactant classes have also been collected in this review. The production volume worldwide…

Direct inverse voltammetric determination of Pb, Cu and Cd in some edible oils after solubilization

1995

The direct determination of traces of certain heavy metals in oils is possible after treatment of the methanolic sample solution with Lumatom (tetramethylammoniumhydroxide). For the inverse voltammetric determination, a flow through cell with a mercury film electrode is used. The results for the determination of Cu and Pb in some edible oils after solubilization agree well with those obtained using wet oxidative high pressure ashing.

Inverse-voltammetric determination of cadmium, lead and copper in animal samples after solubilization

1990

The conditions for the inverse-voltammetric determination of cadmium, lead, and copper in various biological samples after solubilization with Texapon are described. The results of this procedure are compared with those obtained with conventional high- and low-pressure wet digestions. The advantages of the Hg-film electrode as compared to the stationary Hg-electrode are discussed.

Simultaneous determination of acetylsalicylic acid and caffeine in pharmaceuticals by flow injection with fourier transform infrared detection.

1993

Abstract A fast quality control methodology has been developed for the simultaneous determination of acetylsalicylic acid (ASA) and caffeine in pharmaceuticals by flow injection—Fourier Transform Infrared Spectrometry. The method is based on the solubilization of ASA and caffeine in CH2Cl2 and the use of a flow system to introduce samples and standards in the spectrometer. Two solutions, containing 90 and 110% of the reported concentration of the two active principles in the sample, were employed in order to control the extreme tolerance levels accepted by the International Pharmacopeia for the composition of formulations. A 300 μl volume of each solution was injected in turn, into a carrie…

Solubilization of Nitropropane in Copolymer and Surfactant-Copolymer Aggregates

2008

Partitioning study of polycyclic aromatic hydrocarbons between water and some selected water-insoluble phases

2007

An investigation on the partitioning of naphthalene and phenanthrene between water and some water-insoluble phases has been carried out by Uv-vis-NIR spectrophotometry. The analysis of the experimental results emphasized the role of intermolecular interactions and structural features of the hosting phases as driving forces of the partitioning of these polycyclic aromatic hydrocarbons. The critical comparison of the resulting distribution constants allowed to evaluate the potentials of some extracting phases to set up sensitive analytical methods and/or effective environment remediation technologies.

Unveiling the distinctive role of titanium dioxide nanoparticles in aerobic sludge digestion.

2022

Abstract Aerobic digestion is considered to be a common process for the stabilization of waste activated sludge (WAS) in the small-sized wastewater treatment systems, while the broad application of titanium dioxide nanoparticles (TiO2 NPs) results in their unavoidable existence in WAS aerobic digestion, with its role in aerobic sludge digestion being never documented. This study set up a series of aerobic sludge digesters to evaluate the previously unknown role of TiO2 NPs on the performance of the digesters. The volatile solids (VS) degradation percentage increased from 21.9 ± 0.6% to 26.9 ± 0.1% − 30.0 ± 0.3% with the different contents of TiO2 NPs (0, 1, 20 and 50 mg/L). Similarly, the t…

Spectrophotometric evidence for the solubilization site of betalain pigments in membrane biomimetic systems.

2007

The solubilization site of two betalain pigments, namely, betanin and indicaxantin, into l-alpha-dipalmitoyl-phosphatidylcholine (DPPC) and dimyristoylphosphatidylcholine (DMPC) vesicles was investigated by a spectrophotometric study. Pigment absorbance was monitored by varying phospholipid concentration, at a constant temperature that was varied in a range including the main phase transition temperature (Tm) of the relevant phospholipid bilayer. Maximum betanin absorption increased with the increase of DPPC concentration within the entire temperature range, reaching a plateau. The binding constant (Kb) of the pigment, calculated according to a pseudo-two-phase model, varied with the temper…