Reuse of sustainable materials for xylenol orange dye and copper (II) ion ammoniacal removal.

Water pollution caused by heavy metals and organic compounds is an environmental problem with negative impact, making the restoration of water quality a priority. In this paper, the adsorption of xylenol orange dye (XO) on vitreous tuff mineral (VT) was studied. It was established that the adsorption capacity of VT was 45.17 mg/g. The removal was carried out by interactions between active sites on the surface of the material and the functional groups of the dye. The solid waste obtained from this process (VTXO) was reused as adsorbent material for Cu removal in the form of the complex Cu-NH3 because this process was done in an ammoniacal medium. It was found that the adsorption capacity of this new material was 33.09 mg/g. In a previous research, VT mineral was used to remove crystal violet (CV) instead of XO. The solid waste of this last process (VTCV) was also applied for Cu-NH3 removal, in order to compare the adsorption capacity of VT after the adsorption of two different kinds of dyes. The adsorption capacity of VTXO was lower than that of VTCV (71.23 mg/g). In both processes, adsorption kinetic was well described by a chemical adsorption onto a heterogeneous surface. The equilibrium time for XO removal was 50 min and 80 min for Cu-NH3. The experimental design stated that the maximum adsorption capacity was reached when the initial concentration was 6400 mg/L and the solid-liquid ratio was 10 g/L. The system that requires the least amount of adsorbent was the counter flow batch. Finally, it was possible to estimate the behavior of the system on a higher scale. This research provides an efficient and economical alternative to treat water contaminated with dyes and cooper in an ammoniacal medium using the same material in both processes, one after the other.

An attempt for fast separation of enantiomers in nano-liquid chromatography and capillary electrochromatography.

In the present study, an attempt was made to achieve separation of enantiomers within a minute in nano-LC and CEC. In order to achieve this goal several parameters were optimized from the viewpoint of the property of chiral analytes, concentration of the chiral selector in the packing material, capillary dimensions, and separation mode. The enantiomers of several of the applied chiral sulfoxides could be resolved with the analysis time <1 min. Some instrumental obstacles hindering further reduction of analysis time are also highlighted.

Physicochemical effect of activation temperature on the sorption properties of pine shell activated carbon.

Activated carbons produced from a variety of raw materials are normally selective towards a narrow range of pollutants present in wastewater. This study focuses on shifting the selectivity of activated carbon from inorganic to organic pollutants using activation temperature as a variable. The material produced from carbonization of pine shells substrate was activated at 250°C and 850°C. Both adsorbents were compared with commercial activated carbon for the sorption of lead, cadmium, methylene blue, methyl blue, xylenol orange, and crystal violet. It was observed that carbon activated at 250°C was selective for lead and cadmium whereas the one activated at 850°C was selective for the organic dyes. The Fourier transform infrared spectroscopy study revealed that AC850 had less surface functional groups as compared to AC250. Point of zero charge and point of zero salt effect showed that AC250 had acidic groups at its surface. Scanning electron microscopy depicted that increase in activation temperature resulted in an increase in pore size of activated carbon. Both AC250 and AC850 followed pseudo-second-order kinetics. Temkin isotherm model was a best fit for empirical data obtained at equilibrium. The model also showed that sorption process for both AC250 and AC850 was physisorption.

Cyclic sulfoxides-garlicnins K1, K2, and H1-extracted from Allium sativum.

Newly identified cyclic sulfoxides-garlicnins K1 (1), K2 (2), and H1 (3)-were isolated from the acetone extracts of the bulbs of garlic, Allium sativum. Garlicnin H1 (3) demonstrated potential to suppress tumor cell proliferation by regulating macrophage activation. The structures of garlicnins K1 and K2, 3,4-dimethyl-5-allyl-tetrahydrothiophen-2-one-S-oxides, and the structure of garlicnin H1, 3-carboxy-3-hydroxy-4-methyl-5-allylsulfoxide-tetrahydrothiophen-2-(ethane-1,2-diol)-S-oxide were characterized by spectroscopic analysis.

Enantioseparation of selected chiral sulfoxides in high-performance liquid chromatography with polysaccharide-based chiral selectors in polar organic mobile phases with emphasis on enantiomer elution order.

The separation of the enantiomers of 17 chiral sulfoxides was studied on polysaccharide-based chiral columns in polar organic mobile phases. Enantiomer elution order (EEO) was the primary objective in this study. Two of the six chiral columns, especially those based on amylose tris(3,5-dimethylphenylcarbamate) and cellulose tris(4-chloro-3-methylphenylcarbamate) (Lux Cellulose-4) proved to be most successful in the separation of the enantiomers of the studied sulfoxides. Interesting examples of EEO reversal were observed depending on the chiral selector or the composition of the mobile phase. For instance, the R-(+) enantiomer of lansoprazole eluted before the S-(-) enantiomer on Lux Cellulose-1 in both methanol or ethanol as the mobile phase, while the elution order was opposite in the same eluents on amylose tris(3,5-dimethylphenylcarbamate) with the S-(-) enantiomer eluting before the R-(+) enantiomer. The R-(+) enantiomer of omeprazole eluted first on Lux Amylose-2 in methanol but it was second when acetonitrile was used as the mobile phase with the same chiral selector. Several other examples of reversal in EEO were observed in this study. An interesting example of the separation of four stereoisomers of phenaminophos sulfoxide containing chiral sulfur and phosphor atoms is also reported here.

Simultaneous determination of sulphoraphane and sulphoraphane nitrile in Brassica vegetables using ultra-performance liquid chromatography with tandem mass spectrometry.

INTRODUCTION: Several analytical methods exist for the determination of sulphoraphane or sulphoraphane nitrile from biological matrices and plant extracts. However, no UPLC-MS/MS method exists for the simultaneous detection of both. OBJECTIVE: To develop and validate an UPLC-MS/MS method for the simultaneous analysis of sulphoraphane and sulphoraphane nitrile from Brassica oleracea L. ssp. italica METHODS: This method was developed utilising an Acquity BEH C8 column with gradient elution combined with tandem mass spectrometry, using positive electrospray ionisation in multiple reaction monitoring mode. RESULTS: The retention times for sulphoraphane and sulphoraphane nitrile were 0.4 and 0.6 min respectively, and total run time was 3 min. The method was validated for linearity, sensitivity, precision, accuracy, matrix effects and recovery. The method was employed to determine glucoraphanin hydrolysis products in broccoli and the predominant product was found to vary depending on the variety tested. It was also applied to the accurate determination of sulphoraphane and sulphoraphane nitrile in broccoli samples hydrolysed under different conditions. It was observed that the formation of sulphoraphane and sulphoraphane nitrile was influenced by the temperature of the reaction. CONCLUSION: The validated UPLC-MS/MS method for simultaneous detection of sulphoraphane and sulphoraphane nitrile was shown to be applicable to broccoli plants and is expected to be applicable to other cruciferous sources.

Proteome-wide detection and quantitative analysis of irreversible cysteine oxidation using long column UPLC-pSRM.

Reactive oxygen species (ROS) play an important role in normal biological functions and pathological processes. ROS is one of the driving forces for oxidizing proteins, especially on cysteine thiols. The labile, transient, and dynamic nature of oxidative modifications poses enormous technical challenges for both accurate modification site determination and quantitation of cysteine thiols. The present study describes a mass spectrometry-based approach that allows effective discovery and quantification of irreversible cysteine modifications. The utilization of a long reverse phase column provides high-resolution chromatography to separate different forms of modified cysteine thiols from protein complexes or cell lysates. This Fourier transform mass spectrometry (FT-MS) approach enabled detection and quantitation of ataxia telangiectasia mutated (ATM) complex cysteine sulfoxidation states using Skyline MS1 filtering. When we applied the long column ultra high pressure liquid chromatography (UPLC)-MS/MS analysis, 61 and 44 peptides from cell lysates and cells were identified with cysteine modifications in response to in vitro and in vivo H2O2 oxidation, respectively. Long column ultra high pressure liquid chromatography pseudo selected reaction monitoring (UPLC-pSRM) was then developed to monitor the oxidative level of cysteine thiols in cell lysate under varying concentrations of H2O2 treatment. From UPLC-pSRM analysis, the dynamic conversion of sulfinic (S-O2H) and sulfonic acid (S-O3H) was observed within nucleoside diphosphate kinase (Nm23-H1) and heat shock 70 kDa protein 8 (Hsc70). These methods are suitable for proteome-wide studies, providing a highly sensitive, straightforward approach to identify proteins containing redox-sensitive cysteine thiols in biological systems.

Cyclic sulfoxides garlicnins B2, B3, B4, C2, and C3 from Allium sativum.

Several novel sulfides, called garlicnins B2 (1), B3 (2), B4 (3), C2 (4), and C3 (5), were isolated from acetone extracts of garlic, Allium sativum L. and characterized. These garlicnins are capable of suppressing M2 macrophage activation and they have a novel skeleton of cyclic sulfoxide. The structures of the former 3 and latter of 2 were deduced to be 2-(sulfenic acid)-5-(allyl)-3,4-dimethyltetrahydrothiophene-S-oxides and 2-(allyldithiine)-5-(propenylsulfoxide)-3,4-dimethyltetrahydrothiophene-S-oxides, respectively. The mechanism of the proposed production of these compounds is discussed. The identification of these novel sulfoxides from garlic accumulates a great deal of new chemistry in the Allium sulfide field, and future pharmacological investigations of these compounds will aid the development of natural, healthy foods and anti-cancer agents that may prevent or combat disease.

Association of two single-isomer anionic CD in NACE for the chiral and achiral separation of fenbendazole, its sulphoxide and sulphone metabolites: application to their determination after in vitro metabolism.

A NACE method was developed for the separation of fenbendazole (FBZ), a prochiral drug giving rise to chiral (oxfendazole or OFZ) and nonchiral (FBZ sulphone or FBZSO(2)) metabolites. First, the effect of the nature and the concentration of CD as well as that of the acidic BGE on the enantiomeric separation of OFZ were studied. OFZ enantiomers were completely resolved using a BGE made up of 10 mM ammonium formate and 0.5 M TFA in methanol containing 10 mM heptakis(2,3-di-O-acetyl-6-O-sulfo)-beta-CD and 10 mM heptakis(2,3-di-O-methyl-6-O-sulfo)-beta-CD. Moreover, the NACE method was found to be particularly well suited to the simultaneous determination of FBZ, OFZ enantiomers, and FBZSO(2). Thiabendazole was selected as an internal standard. The CD-NACE potential was then evaluated for in vitro metabolism studies using FBZ as a model case. The OFZ enantiomers and FBZSO(2) could be detected after incubation of FBZ in the phenobarbital-induced male rat liver microsomes systems.

Onionin A from Allium cepa inhibits macrophage activation.

Onionin A (1), a new, stable, sulfur-containing compound, was isolated from acetone extracts of bulbs of onion (Allium cepa), and its structure was characterized as 3,4-dimethyl-5-(1E-propenyl)-tetrahydrothiophen-2-sulfoxide-S-oxide, on the basis of the results of spectroscopic analysis. This compound showed the potential to suppress tumor-cell proliferation by inhibiting the polarization of M2 alternatively activated macrophages.

Separation of enantiomers of chiral sulfoxides in high-performance liquid chromatography with cellulose-based chiral selectors using acetonitrile and acetonitrile-water mixtures as mobile phases.

The separation of 14 chiral sulfoxides was systematically studied on 12 cellulose-based chiral columns in acetonitrile and acetonitrile-water mobile phases. Out of all monosubstituted methylphenylcarbamates of cellulose the one having a methyl moiety in position 3 showed more universal chiral resolving ability compared to 2- and 4-substituted derivatives. Out of disubstituted phenylcarbamates of cellulose the ones with methyl substituents showed higher enantiomer resolving ability compared to chloro-substituted ones and substitution in positions 3 of the phenyl moiety was clearly advantageous. From disubstituted derivatives those possessing a combination of methyl- and chloro-substituents were advantageous compared to the ones having dimethyl- or dichloro-substituents. Chiral recognition ability of most chiral selectors towards studied sulfoxides was higher in pure acetonitrile compared to previously studied methanol. The effect of water addition to the mobile phase on analyte retention and enantioseparation was also quite different from that observed with methanol. In particular, with aqueous methanol by increasing the water content in the mobile phase retention increased in most cases and the separation factor improved. In contrast, with aqueous acetonitrile retention and separation factors decreased up to a certain water content in the mobile phase and then started to recover again for most of the studied analytes.

Withanolide sulfoxide from Aswagandha roots inhibits nuclear transcription factor-kappa-B, cyclooxygenase and tumor cell proliferation.

Investigation of the methanol extract of Aswagandha (Withania somnifera) roots for bioactive constituents yielded a novel withanolide sulfoxide compound (1) along with a known withanolide dimer ashwagandhanolide (2) with an S-linkage. The structure of compound 1 was established by extensive NMR and MS experiments. Compound 1 was highly selective in inhibiting cyclooxygenase-2 (COX-2) enzyme by 60% at 100 microm with no activity against COX-1 enzyme. The IC(50) values of compound 1 against human gastric (AGS), breast (MCF-7), central nervous system (SF-268) and colon (HCT-116) cancer cell lines were in the range 0.74-3.63 microm. Both S-containing dimeric withanolides, 1 and 2, completely suppressed TNF-induced NF-kappaB activation when tested at 100 microm. The isolation of a withanolide sulfoxide from W. somnifera roots and its ability to inhibit COX-2 enzyme and to suppress human tumor cell proliferation are reported here for the first time. In addition, this is the first report on the abrogation of TNF-induced NF-kappaB activation for compounds 1 and 2.

Cyclic sulfur-containing compounds from Allium fistulosum 'Kujou'.

Sulfur-containing compounds, allicin and ajoene, etc., were isolated from Allium species. In a recent study, some sulfur-containing cyclic compounds were isolated from A. sativum, A. cepa, and A. fistulosum. Four new compounds with multiple rings with methyl disulfide or propyl disulfide at the side chain of the 7-position, kujounins A3 (1), B1 (2), B2 (3) and B3 (4), and two new thiolane type compounds with methoxy and methyl sulfoxide moiety at the 2- and 5-positions, and allium sulfoxides A2 (5) and A3 (6), were isolated from the acetone extract of the fresh white parts of Allium fistulosum 'Kujou' with three known compounds, kujounin A1 (7) and A2 (8), and allium sulfoxide A1 (9). The chemical structures of the new compounds were elucidated on the basis of physicochemical evidence. The kujounins had a rare molecular skeleton, which was tetrahydro-2H-difuro[3,2-b:2',3'-c]furan-5(5aH)-one.

S-alkenyl cysteine sulfoxide and its antioxidant properties from Allium cepa var. tropeana (red onion) seeds.

A new cysteine sulfoxide, (S(S)R(C))-S-(3-pentenyl)-L-cysteine sulfoxide (1), was identified from the seeds of Allium cepa var. tropeana, together with the known methiin, etiin, alliin, isoalliin, propiin, and butiin. The structure of compound 1 was established by analysis of its physical and spectroscopic data. The antioxidant activity of an extract containing cysteine sulfoxides and compound 1 was evaluated using the FRAP and DPPH tests.

Enantioseparation of chiral sulfoxides using teicoplanine chiral stationary phases and kinetic study of decomposition in human plasma.

Teicoplanin chiral stationary phases (CHIROBIOTIC TAG and CHIROBIOTIC T) used in this study are suitable for enantioseparation of chiral sulfoxides in polar-organic phase mode. The method involves determination of chiral sulfoxides in human plasma on teicoplanin chiral stationary phase after the off-line SPE pre-treatment using OASIS HLB cartridges. The limit of determination was in the range of 0.004-0.026 microg/ml for individual racemic mixtures. The S(+) enantiomeric form eluted always as the first, except the 4-(methyl sulfinyl) biphenyl with less retained R(-) enantiomer. It was found that the rate constants of individual chiral sulfoxides depend on the type of halogen substituent. There was no significant difference in rate constants considering the position of Cl-substitution on aromatic ring of sulfoxides. Moreover, the rate constants of R(-) and S(+) forms of enantiomers are significantly different just in the case of 4-fluoro phenyl sulfoxide.

Separation of enantiomers of selected chiral sulfoxides with cellulose tris(4-chloro-3-methylphenylcarbamate)-based chiral columns in high-performance liquid chromatography with very high separation factor.

The present study reports successful separations of enantiomers of selected chiral sulfoxides with very high separation factor in high-performance liquid chromatography by using chiral columns prepared with the chiral selector cellulose tris(4-chloro-3-methylphenylcarbamate). High separation factors were observed in polar organic, as well as in hydrocarbon-alcohol-type mobile phases. The key structural components of the solute for obtaining high chiral recognition are discussed as well as thermodynamic quantities of analyte adsorption on the chiral stationary phase were determined. Experiment aimed at the enantioselective extraction of racemates from solution are also described.

Separation of enantiomers of chiral sulfoxides in high-performance liquid chromatography with cellulose-based chiral selectors using methanol and methanol-water mixtures as mobile phases.

The interplay between structural details of chiral analytes and selectors in the separation of 14 chiral sulfoxides was systematically studied on 18 different polysaccharide-based chiral columns. Retention and enantioselectivity of a set of chiral sulfoxides were of primary interest. Several of chiral columns studied exhibited quite powerful chiral recognition ability in pure methanol. With addition of water to the mobile phase retention increased in the most cases and the separation factor improved. However, several exceptions were also noted. Of monosubstituted phenylcarbamates of cellulose as chiral selectors, chlorosubstituted ones did not show better enantiomer resolving ability compared to unsubstituted cellulose tris(phenylcarbamate). Out of disubstituted phenylcarbamates of cellulose the ones with methylsubstituents showed higher enantiomer resolving ability compared to chloro-substituted ones and substitution in positions 3 and 5 of the phenyl moiety was clearly advantageous. From disubstituted derivatives those possessing a combination of methyl- and chloro-substituents were advantageous compared to the ones having dimethyl- or dichloro-substituents. Interesting examples of reversal in enantiomer elution order (EEO) were observed on cellulose tris(4-chloro-3-methylphenylcarbamate)- and cellulose tris(3-chloro-4-methylphenylcarbamate)-based chiral stationary phases (CSPs) function of the water content in the mobile phase.

Enantioseparation of novel chiral sulfoxides on chlorinated polysaccharide stationary phases in supercritical fluid chromatography.

Asymmetric sulfoxides is a particular case of chirality that may be found in natural as well as synthetic products. Twenty-four original molecules containing a sulfur atom as a centre of chirality were analyzed in supercritical fluid chromatography on seven polysaccharide-based chiral stationary phases (CSP) with carbon dioxide - methanol mobile phases. While all the tested CSP provided enantioseparation for a large part of the racemates, chlorinated cellulosic phases proved to be both highly retentive and highly enantioselective towards these species. Favourable structural features were determined by careful comparison of the enantioseparation of the probe molecules. Molecular modelling studies indicate that U-shaped (folded) conformations were most favorable to achieve high enantioresolution on these CSP, while linear (extended) conformations were not so clearly discriminated. For a subset of these species adopting different conformations, a broad range of mobile phase compositions, ranging from 20 to 100% methanol in carbon dioxide, were investigated. While retention decreased continuously in this range, enantioseparation varied in a non-monotonous fashion. Abrupt changes in the tendency curves of retention and selectivity were observed when methanol proportion reaches about 60%, suggesting that a change in the conformation of the analytes and/or chiral selector is occurring at this point.

The role of molecular interaction fields on enantioselective and nonselective separation of chiral sulfoxides.

The separation of a series of 23 asymmetric sulfoxides, including the three proton pump inhibitors (PPI) omeprazole, lansoprazole and pantoprazole was investigated by HPLC, under reversed-phase elution with amylose tris(3,5-dimethylphenylcarbamate), amylose tris[(S)-1-phenylethylcarbamate] and amylose tris(3,5-dimethoxyphenylcarbamate) chiral stationary phases, CSP1-3, respectively. The whole set of sulfoxides showed better enantioselectivity and enantioresolution on CSP1. However, the three PPI were enantioseparated only when using CSP1 and CSP3. It was observed an improved enantioselectivity and enantioresolution on CSP3. The mechanisms of retention were evaluated by molecular interaction fields (MIF) generated via GRID force field, which yielded the geometric reasons leading to the scenario outlined. The enantioselective and nonselective interactions are discussed in terms of the reported selectivity. The steric structural outline of the CSP nonselective interaction sites is of major importance to deliver the sulfoxides to the chiral selective sites where the enantioselective interactions take place.

Development of dinitrophenylated cyclodextrin derivatives for enhanced enantiomeric separations by high-performance liquid chromatography.

The synthesis and evaluation of new dinitrophenyl (DNP) substituted beta-cyclodextrin (beta-CD) chiral stationary phases (CSPs) for the enantioseparation of various classes of chiral analytes by HPLC are presented. The dinitrophenyl substituted beta-CD derivatives are synthesized and covalently bonded to functionalized 5 microm spherical porous silica gel. These are the first reported derivatized cyclodextrin which contains pi-electron deficient substituents (i.e., pi-acidic moieties). The column performance in terms of their ability to separate enantiomers is evaluated. A variety of different dinitro-substituted aryl groups are investigated and compared. The pH of the mobile phase buffers, the buffer composition, the number and position of the dinitro groups on the phenyl ring substituent, the degree of substitution, and the bonding strategy all greatly affect the performance of the CSPs. A large variety of racemic compounds have been separated successfully on these CSPs. The bonded dinitrophenyl-derivatized cyclodextrins are stable in all three mobile phase modes, namely, the reversed-phase, polar organic, and normal phase modes. No degradation in column performance was observed in any mode of operation even after more than 1000 injections. The analytical applicability of these types of CSPs for enantiomeric separations is discussed in detail.