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Dry (D.E.) and liquid (L.E.) extracts were prepared from flaxseeds and their application in health field was evaluated. The chemical analysis showed that D.E. is rich in the lignan secoisolariciresinol diglucoside and L.E. in unsaturated triglycerides containing linolenic acid. Mainly, D.E. showed reducing (15.73 μmol Fe2+/g) and radical scavenging capacities (5.25 mg TE/g) and ability to down-regulate the expression of the pro-inflammatory cytokines NO (IC50 = 0.136 ± 0.009 mg/mL) and IL-6 (IC50 = 0.308 ± 0.103 mg/mL), suggesting its use in wound treatment. D.E. and L.E. were active against S. pyogenes and D.E. also against S. aureus. The two extracts were combined in a novel O/W emulgel in which the water phase was viscosized using a low molecular weight and highly deacetylated chitosan (1% wt./v). The presence of this polymer in the emulgel decreased the MIC values of the extracts. In fact, MIC shifted from 0.59 mg/mL to 0.052 mg/mL for D.E. and from 0.22 mg/mL to 0.036 mg/mL for L.E., concentrations safe both for keratinocytes and macrophages. Moreover, the emulgel demonstrated to inhibit S. aureus, P. aeruginosa, S. pyogenes, E. coli, and K. pneumoniae growth (inhibition halos 24–36 mm), strains often responsible for diabetic foot ulcer infection.

A number of analytical studies, started in the sixties of the last century, concerning the stem bark of Geissospermum vellosii, have documented the presence of a number of indole alkaloids whose molecular identity was defined by NMR technique. The potential bioactivity of these compounds has inspired more recent analogous studies either devoted to structural elucidation of new alkaloid molecules or to the investigation of the role of some of them in cancer therapy. Anyway, a complete fingerprinting of the bark content is still lacking. In this paper, after a suitable extraction step, we obtain a chromatographic separation showing a number of components higher than the number of alkaloids so far described. Considering the great number of substances present in the stem bark, their identification is practically impossible to reveal by NMR techniques. As we presume that there are other stem bark unidentified alkaloids with important bioactivity, we propose to characterize their molecular structures by UV-Vis Diode Array spectrophotometry and High-Resolution Multistage Mass Spectrometry. The two adopted detection techniques were first tested on the already known Geissospermum vellosii molecules, and, after an inspection of their efficacy, were applied to the substances that have not yet been described. Herewith we propose the molecular structures of 10 substances that were never previously described, and in addition we provide experimental evidence of the presence of 6 already known substances which were never reported in the Geissospermum genus. A far more detailed description of the bark constituents is therefore provided.

The onion non-edible outside layers represent a widely available waste material deriving from its processing and consumption. As onion is a vegetable showing many beneficial properties for human health, a study aiming to evaluate the use of extract deriving from the non-edible outside layers was planned. An eco-friendly extraction method was optimized using a hydroalcoholic solution as solvent. The obtained extract was deeply characterized by in vitro methods and then formulated in autoadhesive, biocompatible and pain-free hydrogel polymeric films. The extract, very soluble in water, showed antioxidant, radical scavenging, antibacterial and anti-inflammatory activities, suggesting a potential dermal application for wounds treatment. In vitro studies showed a sustained release of the extract from the hydrogel polymeric film suitable to reach concentrations necessary for both antibacterial and anti-inflammatory activities. Test performed on human keratinocytes showed that the formulation is safe suggesting that the projected formulation could be a valuable tool for wound treatment.

Cantor’s ternary function is generalized to arbitrary base-change functions in non-integer bases. They turn out to have radically different continuity, differentiability and monotonicity properties, depending on the particular bases involved in their definition.

The aim of this study was to develop an innovative formulation, particularly useful for the treatment of exuding wounds. An extract from Moringa oleifera leaves (MOE), prepared by an eco-friendly method, was used as active ingredient. Its preliminary characterization showed that MOE is rich in quercetin-O-glucoside and quercetin-O-malonyl glucoside, responsible for the antioxidant, radical scavenging and antibacterial activities (toward Staphylococcus aureus, S. epidermidis, S. faecalis and S. pyogenes). Moreover, MOE showed the ability to stimulate keratinocytes growth. Thus, bioadhesive biocompatible polymeric microparticles loaded with such extract were developed and prepared in order to treat exuding wounds. The microparticles, obtained by spray drying, using chitosan as polymer, showed good swelling ability. This is useful to obtain the transition from microparticles to a continuous gel covering the wound, after deposition on it. This has the double function to protect the damage area and to promote the healing. The in vitro release study showed that the formed gel is able to release immediately MOE, in the first minutes after application, and to promote a sustained release within 24 h reaching an efficacious concentration against the most sensitive bacterial strains. These findings suggest that the developed microparticles represent an interesting tool for exuding wounds treatment.

Aim: The increased consumption of traditional medicinal plants has been driven by the notion that herbal products are safe and efficient. The purpose of this study was to evaluate the safety and the protective effect of a hydro alcoholic extract of Desmodium adscendens (DA) on liver (HEPG2) and kidney (LLC-PK1) cells. Materials and Methods: A hydro alcoholic extract of DA was used. HEPG2 or LLC-PK1 cells were treated with different does of DA, and viability test (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium [MTS]), cytotoxicity assay lactate dehydrogenase (LDH release) and study of the cell morphology were used in order to determine effects of DA on these two cells. Results: A viability test (MTS), a cytotoxicity assay LDH release and a study of the cell morphology revealed that pretreatment with 1 mg/ml or 10 mg/ml DA did not alter viability or LDH release in HEPG2 or LLC-PK1 cells. However, DA at the dose of 100 mg/ml significantly decreased cell viability, by about 40% (P < 0.05). Further, MTS studies revealed that DA 1 mg/ml or 10 mg/ml protected LLC-PK1 cells against a glucose-induced oxidative stress of 24 h (P < 0.05). Conclusion: Hence, the lowest concentrations of DA (1 mg/ml and 10 mg/ml) were safe for HEPG2 and LLC-PK1 and protective against an oxidative stress in LLC-PK1 cells. These data suggest that DA extracts used as a traditional herbal as food health supplements should be used at the lowest dosage.

Natural sources of triacylglycerols containing ω-3 fatty acids are of particular interest due to their protective role against several human diseases. However, as it has been well ascertained, the position of the ω-3 fatty acid on the triacylglycerol backbone influences how digestion occurs. In particular, occurrence at the sn-2 position allows optimal intestinal absorption conditions. The analytical protocol for regioisomer characterisation of fatty acids in a triacylglycerol usually requires the use of stereospecific lipases before instrumental identification. In this paper, we propose a more direct instrumental determination of triacylglycerol composition along with sn-2 positional identification of the fatty acids constituents by Liquid Chromatography-High Resolution Mass Spectrometry. Different intensities of product signals obtained in MS(2) and MS(3) experiments were used to define an interpretative scheme able to rationalise the stereochemistry of the TAGs. Marine matrices like tuna and algae oils have been studied in detail, their triacylglycerols identified and sn-2 positional arrangement of fatty acid constituents assessed.

In this study, raw materials, sturgeon and brill roe, were analyzed and compared as regard their use in cosmetic products. Recently, expensive caviar was largely used in beauty creams as lipids source. We compared lipids from caviar and brill eggs to propose a technological alternative. The fatty ac...

RATIONALE A comprehensive study of the environmental fate of pollutants is more and more required, above all on new contaminants, i.e. pharmaceuticals. As high-resolution mass spectrometry (HRMSn) may be a suitable analytical approach for characterization of unknown compounds, its performance was evaluated in this study. METHODS The analyses were carried out using liquid chromatography (LC) (electrospray ionization (ESI) in positive mode) coupled with a LTQ-Orbitrap analyzer. High-resolution mass spectrometry was employed to assess the evolution of the drug transformation processes over time; accurate masses of protonated molecular ions and sequential product ions were reported with an error below 5 millimass units, which guarantee the correct assignment of their molecular formula in all cases, while their MS2 and MS3 spectra showed several structurally diagnostic ions that allowed characterization of the different transformation products (TPs) and to distinguish the isobaric species. RESULTS The simulation of phototransformation occurring in the aquatic environment and identification of biotic and abiotic transformation products of the two pharmaceuticals were carried out in heterogeneous photocatalysis using titanium dioxide, aimed to recreate conditions similar to those found in the environmental samples. Twenty-eight main species were identified after carbamazepine transformation and twenty-nine for clarithromycin. CONCLUSIONS This study demonstrates that HRMS, combined with LC, is a technique able to play a key role in the evaluation of the environmental fate of pollutants and allows elucidation of the transformation pathways followed by the two drugs. Copyright © 2012 John Wiley & Sons, Ltd.

In this paper, a comprehensive study of the fate of an antibiotic, lincomycin, in the aquatic environment is presented. High-resolution mass spectrometry was employed to assess the evolution of the process over time. Formation of intermediate compounds was followed by high performance liquid chromatography-high resolution mass spectrometry (LC-HRMS); accurate mass-to-charge ratios of parent ions were reported with inaccuracy below 1 mmu, which guarantee the correct assignment of their molecular formula in all cases, while their MS2 and MS3 spectra showed several structural-diagnostic ions that allowed to characterize the different transformation products (TPs) and to discriminate the isobaric species. The simulation of phototransformation occurring in the aquatic environment and the identification of biotic and abiotic TPs of the pharmaceutical compound were carried out in different experimental conditions: dark experiments, homogeneous photolysis and heterogeneous photocatalysis using titanium dioxide, in order to recreate conditions similar to those found in the environment. Twenty-one main species were identified afterwards lincomycin transformation. Several isomeric species were formed and characterized by analyzing MS and MSn spectra and by comparison with parent molecule fragmentation pathways. The major transformation process for lincomycin is hydroxylation either at N-alkyl side chain or at the pyrrolidine moiety. In addition, oxidation/reduction, demethylation or cleavage of pyranose ring occurs. Based on this information and additional assessment of profiles over time of formation/disappearance of each species, it was possible to recognize the transformation pathways followed by the drug. Copyright © 2012 John Wiley & Sons, Ltd.

Physicochemical deterioration processes driven by lithobiontic microcolonial fungi (MCF) and endolithic lichens (EL) are still mostly unresolved. Here, the millimetric penetration of MCF strains within silicate and carbonate lithotypes was quantified. The influence of petrographic features in determining hyphal passageways satisfies a model of physical penetration during the early stages of colonization, already described for EL. The MCF and EL secretion of iron-chelating metabolites accounts for iron mobilization in desert-varnish formation, often putatively related to fungal colonization. Increased dissolution of limestone by the model iron chelator desferrioxamine indicates the possible involvement of these MCF and EL secretes in pitting carbonates.

Two horses were treated with sildenafil, and its metabolic products were sought in both urine and plasma samples. Prior to this, a simulative laboratory study had been done using a photocatalytic process, to identify all possible main and secondary transformation products, in a clean matrix; these were then sought in the biological samples. The transformation of sildenafil and the formation of intermediate products were evaluated adopting titanium dioxide as photocatalyst. Several products were formed and characterized using the HPLC/HRMSn technique. The main intermediates identified in these experimental conditions were the same as the major sildenafil metabolites found in in vivo studies on rats and horses. Concerning horse metabolism, sildenafil and the demethylated product (UK 103,320) were quantified in blood samples. Sildenafil propyloxide, de-ethyl, and demethyl sildenafil, were the main metabolites quantified in urine. Some more oxidized species, already formed in the photocatalytic process, were also found in urine and plasma samples of treated animals. Their formation involved hydroxylation on the aromatic ring, combined oxidation and dihydroxylation, N-demethylation on the pyrazole ring, and hydroxylation. These new findings could be of interest in further metabolism studies. Copyright © 2011 John Wiley & Sons, Ltd.

This paper deals with the photocatalytic transformation of N,N-diethyl-m-toluamide (DEET), one of the most widespread and efficient mosquito repellents, under simulated solar irradiation using titanium dioxide as the photocatalytic source of oxidizing species. The investigation involved monitoring of the DEET decomposition, the identification of intermediate compounds and the assessment of mineralization. High-resolution mass spectrometry was employed to assess the evolution of the photocatalyzed process over time. Fifty-one main species were identified after DEET transformation. Several isomeric species were formed and were characterized by analyzing MS and MSn spectra in full, and by comparison with parent molecule fragmentation pathways. In the DEET molecule, the initial transformation involved mono- and polyhydroxylation followed by oxidation of the alcohol groups, cleavage of the alkyl chains or ring opening. All these intermediates are easily degraded and DEET is completely mineralized after 4 h of irradiation. Microtox bioassay (Vibrio fischeri) was employed to evaluate the ecotoxicity of solutions treated by photocatalysis. Copyright © 2010 John Wiley & Sons, Ltd.

Spiramycin, a widely used veterinary macrolide antibiotic, was found at traceable levels (nanograms per litre range) in Po River water (N-Italy). The aqueous environmental fate of this antibiotic compound was studied through drug decomposition, the identification of the main and secondary transformation products (TPs), assessment of mineralisation and the investigation of drug TPs toxicity. Initially, laboratory experiments were performed, with the aim of stimulating the antibacterial transformation processes followed in aquatic systems. The TPs were identified through the employment of the liquid chromatography (LC)-mass spectrometry technique. Under illumination, spiramycin degraded rapidly and transformed into numerous organic (intermediate) compounds, of which 11 could be identified, formed through five initial transformation routes. These laboratory simulation experiments were verified in situ to check the mechanism previously supposed. Po River water was sampled and analysed (by LC-high-resolution mass spectrometry) at eight sampling points. Among the previously identified TPs, five of them were also found in the river water. Three of them seem to be formed through a direct photolysis process, while the other two are formed through indirect photolysis processes mediated by natural photo sensitisers. The transformation occurring in the aquatic system involved hydroxylation, demethylation and the detachment of forosamine or mycarose sugars. Toxicity assays using Vibrio fischeri proved that even if spiramycin did not exhibit toxicity, its transformation proceeded through the formation of toxic products.

The photocatalytic treatment of soil washing wastes containing the pesticide swep and three different surfactants: sodium dodecylsulfate (SDS), hexadecyltrimethylammonium bromide (HTAB) and polyoxyethylene(8) dodecyl ether (C 12 E 8 ), has been investigated. Better extraction performances of swep (methyl-N-(3,4-dichlorophenyl)carbamate) from contaminated soil samples have been obtained using aqueous SDS solutions. The pesticide abatement in the wastes, performed by photocatalysis in the presence of irradiated TiO 2 dispersions, was faster in the presence of SDS and slower in the presence of HTAB, whereas a marked degradation inhibition was observed when C 12 E 8 solutions were used. The monitoring of end products formation in water, together with a detailed MS examination of the transient intermediates formed during the earlier steps of the pesticide degradation, allowed to give insight into the process mechanism operating in aqueous media.

Central composite design (CCD) based on response surface methodology (RSM) was employed in the present study in combination with "profiling and desirability function" to evaluate the effects of main variables (TiO(2), H(2)O(2), and light intensity) affecting 4-methylbenzylidene camphor (4-MBC) photocatalytic degradation and for optimization of the process. Besides statistical optimization of the UV filter decomposition, the investigation involved a study of the identification of intermediate compounds, mineralization, as well as toxicity evaluation. The transformation of 4-MBC proceeds through: (i) demethylation of the bridged structure; (ii) hydroxylation of the methylbenzylidene moiety; (iii) bihydroxylation/demethylation reaction. Even if all the identified compounds are degraded themselves within 30 min, the complete carbon mineralization is only achieved after 24 h of irradiation. Toxicity assays using Vibrio fischeri, have shown that 4-MBC intermediates exhibit acute toxicity. (C) 2009 Elsevier B.V. All rights reserved. Applied Catalysis B-Environmental

The diffusion of drug residues in wastewaters and surface waters as rivers and streams may constitute a problem for the environment, with consequences on the ecosystem and also on the human health. This paper deals with the study of the photo-induced transformation of amiloride, an orally administered diuretic agent, under simulated solar light. Direct photolysis and photocatalyzed degradation processes, using titanium dioxide as a photocatalyst, were investigated. The study involved the monitoring of the drug decomposition, the identification of intermediate compounds of the decomposition, the assessment of mineralization, as well as the evaluation of the toxicity associated to the degradation products. Amiloride underwent complete degradation within 30min of irradiation (heterogeneous photocatalysis) or 4h (homogeneous photolysis). HPLC coupled to HRMS, via ESI interface, demonstrated to be a powerful tool to identify and measure degradation products of the studied drug. By considering the photocatalytic process, the identified intermediates are formed through: (1) dechlorination and hydroxylation of the heteroaromatic ring; (2) the detachment of the guanidinic moiety; (3) cleavage of the heteroaromatic ring. The drug photomineralization was a rather slow process and after 4h of irradiation 25% of the total organic carbon (TOC) was still present. Chlorine was stoichiometrically released as chloride ions within the considered irradiation times (4h), while nitrogen was only partially converted into ammonium ions. This was due to the formation of guanidine, known to be hardly mineralized photocatalytically, and some other small molecules still containing the nitrogen. Acute toxicity, measured with a Vibrio fischery assay, showed that amiloride transformation proceeded through the formation of toxic compounds.

The analysis of diuretic compounds has become of great concern because of their extensive use both in therapy and in illicit treatments (such as masking agents in sport doping and drug abuse). The variety of chemical structures of this class of drugs encouraged the development of new methods and techniques of analysis, especially as regards to acidic compounds. LC/MS has so grown to be the reference technique for this kind of analysis in forensic and anti-doping confirmation purposes. Multiple stage MS permits identification of single drugs with high selectivity, but some unexpected pathways could weaken the entire process. In this work we aim to explain some unusual fragmentation steps using high-resolution MS n . For example, in the case of amiloride an intense product ion in MS 3 analysis generates an apparent loss of 10 Da. Water adduct formation and successive carbon monoxide elimination can explain this uncommon behavior, which was studied using different ion traps. Bendroflumethiazide MS n spectra show instead three successive HF losses, in spite of the presence of a radical site in the parent structure. Homolytic cleavages with radical ion production occur also in the case of protonated positive ion of ethacrynic acid (loss of chlorine radical) showing that such fragmentation behavior is not so rare as generally reported. Different ionization modes were studied and a tentative correlation with acidic-base properties was done. Multiple stage high-resolution mass spectra of positive and negative ions were discussed.

Phenolic compounds (flavonoids and phenolic acid derivatives) are major active constituents of the resinous fraction of propolis, and also represent its allergenic principles. We have developed a chromatography electrospray ionisation tandem mass spectrometry (HPLC-ESI-MS/MS) method to characterise the polyphenolic fraction of propolis rapidly and quali-quantitatively. With precursor ion scanning, selective detection of caffeic esters was easily achieved, confirming the identification of prenyl caffeate, benzyl caffeate and phenylethyl caffeate by comparison with synthetic standards. The ionisation and fragmentation behaviour of the major propolis flavonoids was rationalised and applied to selected real samples. Taken together, the results of this study show that the introduction of precursor ion analysis leads to a significant improvement in the characterisation of the phenolic fraction of propolis, paving the way to the establishment of a better quality control for this important natural remedy.

The present paper deals with the photocatalytic transformation of salbutamol [2-(tert-butylamino)-1-(4-hydroxyl-3-hydroxymethylphenyl)ethanol] under simulated solar irradiation using titanium dioxide as a photocatalyst. The investigation has involved a kinetic study of the drug decomposition, the identification of intermediate compounds, the assessment of mineralization, as well as toxicity evaluation. The variation of TiO2 concentration and pH on the reaction rate was investigated. The use of the response surface methodology allowed to fit the optimal values of the parameters leading to the degradation of the micro-pollutant. High resolution mass spectrometry was employed in assessing the temporal course of the photocatalyzed process. According to our findings, a tentative degradation pathway is proposed for the photocatalytic degradation of salbutamol based on the formation of both oxidative and reductive compounds. 2-(Methylamino)-1-(4-hydroxyl-3-methylphenyl)ethanol, 2-(tertbutylamino)-1-(4-hydroxylphenyl)ethanol, 2-(tert-butylamino)-1-(3,4-dihydroxyphenyl)ethanol, 2-(tert-butylamino)-1-(4-hydroxyl-3-methylphenyi)ethanol, and 2-(tert-butylamino)-1-(3,4-dihydroxyphenyl)ethanone are initially formed, which are then transformed into 2-(tert-butylamino)-acetic acid and hydroquinone. All these intermediates are easily degraded themselves and until 2 h of irradiation 2-(tert-butylamino)-acetic acid is the only compound recognized to endure. Photomineralization of the substrate was rather a quick process; within 2 h of irradiation nitrogen is completely mineralized, where the amino moiety is mainly transformed into NH4+ and in a lesser extent into NO3- ions (ratio 2:1). Carbon complete mineralization is achieved within 3 h of irradiation. Finally, Microtox bioassay (Vibrio fischeri) was employed in evaluating the ecotoxicity of solutions treated by photocatalysis. (C) 2007 Elsevier B.V. All rights reserved. Applied Catalysis B-Environmental

The photo-induced transformation of methyl and methyl acetic acid guanidine derivatives, which are the decomposition products of several pollutants, was studied adopting titanium dioxide as photocatalyst. The in-depth investigation of the overall process involved studying the evolution of intermediate compounds, the fate of organic nitrogen and the rate (and extent) of carbon mineralization. Intermediate products were identified with an HPLC/tandem MS instrument, thus enabling a transformation mechanism applicable to methyl-guanidinic derivatives to be defined. The derivatives are chiefly transformed through a combination of reductive and oxidative processes. Photocatalytically assisted hydrolysis, through sequential reactions involving OH/e−/H+, induces a demethylation process that, in all cases, leads to the formation of guanidine, then (very slowly) to its mineralization. Similarly, also with creatine and creatinine the main transformation pathway proceeds through a photocatalytically assisted hydrolysis that leads to the formation of 2-imino-imidazole-4-one (from creatinine) and guanidine acetic acid and methyl guanidine (from creatine). Guanidine is the ultimate intermediate compound recognized in these cases, too. The fate of nitrogen was also evaluated in all cases. The organic nitrogen is mainly released as nitrate ions, with [NH4+]:[NO3−] ratios ranging from 1:2 for creatine to 1:8 with methylguanidine.

Salvia divinorum Epling & Jativa-M. is a perennial herb belonging to the Lamiaceae family; its active ingredient, the neoclerodane diterpene salvinorin A, is a psychotropic molecule that produces hallucinations. A comparative evaluation of S. divinorum fresh and dried leaves, S. officinalis fresh leaves, and dried powdered leaves claimed to be S. divinorum was done. HPLC-MS data confirmed the presence of salvinorin A in both S. divinorun leaf extracts and the powdered leaves, whereas no salvinorin A was found in S. officinalis. The non-transcribed spacer (NTS) in the 5S-rRNA gene of all leaf samples and the dried powdered leaves was amplified by PCR using a pair of primers located at the 3' and 5' ends of the coding sequence of 5S-rRNA gene. The resulting PCR products (about 500bp for S. divinorum and 300bp for S. officinalis) were gel purified, subcloned into pGEM-T Easy vector and sequenced. By aligning the isolated nucleotide sequences, great diversities were found in the spacer region of the two species. Specific S. divinorum primers were designed on the sequence of the 5S-rRNA gene spacer region. In addition, a PCR-restriction fragment length polymorphism (PCR-RFLP) method was applied using NdeI and TaqI restriction enzymes. An NdeI site, absent in S. officinalis, was found in S. divinorum NTS region at 428-433bp. For TaqI, multiple sites (161-164, 170-173, and 217-220bp) were found in S. officinalis, whereas a unique site was found in S. divinorum (235-238bp). The results of this work show that the combined use of analytical chemical (HPLC-MS) and molecular (DNA fingerprinting) methods lead to the precise and unequivocal identification of S. divinorum.

Cinosulfuron is a sulfonylurea herbicide largely used in the extensive cultures of flooded rice in North Italy. The degradation of cinosulfuron has been investigated in sterile aqueous solutions at 30 degrees C at different pH values. It was rapidly degraded at acidic pH (half-lives 3, 9 and 43 days at pH 4, 5 and 6, respectively) while the half-life was > 1 year at pH 7 and 9. Two degradation products formed by cleavage of the sulfonylurea bridge were identified by LC-MS. Degradation by selected mixed microbial cultures tested in aerobic and anaerobic conditions was very slow and attributable to chemical hydrolysis due to the acidic pH of the cultural broths. Degradation took place in freshly collected rice field water treated for two years with cinosulfuron but, in this case also, chemical hydrolysis prevailed over microbial degradation. In contrast, in flooded sediment simulating the paddy field environment, the dissipation rate of cinosulfuron was higher than expected from chemical hydrolysis according to the pH of the system, indicating the involvement of soil microflora. Although the herbicide exhibited a reduced affinity for the sediment surfaces demonstrated by the low value of the K(f) Freundlich coefficient (0.87 on a micromolar basis), the rapid dissipation observed in the simulated paddy field should prevent its leaching to ground water.

The photocatalytic degradation in aqueous solution of aminopyrimidines (2-aminopyrimidine, 4-aminopyrimidine, 4-methyl-2-aminopyrimidine, 2,6-dimethoxy-4-aminopyrimidine) on TiO2 has been investigated. Their transformation pathways seem to be closely related to the position of the amino group in the heterocyclic ring; especially the fate of the organic nitrogen is deeply influenced. Both the ratio [NH4+]/[NO3−] and the extent of their formation are connected to the nature of the substituents and the amino group position in the heteroaromatic ring. When the amino group is located in C4, the transformation pathways proceed mainly through the cleavage of the CN bonds, with the formation of oxygenated structures as intermediates and the release of nitrogen mainly as ammonium ions. In this case, the stoichiometric conversion of nitrogen into inorganic ions and the complete mineralization is achieved within few hours of irradiation. On the contrary, when the amino group is held in C2, a lack in both nitrogen and carbon mineralization is observed. It is attributable to the stoichiometric conversion of the NC(NH2)N moiety into guanidine, a very stable compound for which the mineralization is obtained only at long irradiation times (>70 h). Interestingly, in this latter case the nitrogen is mainly released as nitrate ions.

Aqueous suspensions of titanium dioxide containing sulphonamides have been irradiated with near-UV light. The transformation processes have been followed by monitoring both the organic intermediates and the final products. The disappearance of sulphonamides and the formation of organic intermediates have been pursued through an HPLC/MS instrument. The degradation of all the investigated sulphonamides (sulphamerazine, sulphadiazine, sulphadimethoxine and sulfathiazole) is achieved through the breaking of the SN bond and through an OH attack on the aromatic rings. The more intriguing matter is the fate of the intermediates originated through the cleavage of the SN bond. A structure like RNH2 is formed, whose fate is highly dependent on the nature of R. From sulphathiazole and sulphadimethoxine, this intermediates (2,6-dimethoxy-4-aminopyrimidine and 2-aminothiazole) undergo a further degradation, so bringing to the ring-opening and to the release of the nitrogen contained in these structures. In fact, in both cases the parallel release of sulphur and nitrogen from the molecule is realized. Sulphur is finally found as sulphate ions, while nitrogen is transformed into nitrate and ammonium ions. The N-containing intermediates formed from sulphadiazine and sulphamerazine (4-methyl-2-aminopyrimidine) is highly persistent and does not release the nitrogen in the investigated times.

Mepanipyrim, a widely used pyrimidinic fungicide, has been photocatalytically degraded in aqueous solution on TiO2. The purpose of this study is to artificially produce degradation compounds similar to those formed in the environment. Numerous intermediates have been identified and characterised through a MSn spectra analysis, allowing us to give insight into the early steps of the degradation process. Several concomitant pathways occur concerning both reductive and/or oxidative attacks; the main steps involve the cleavage of triple bond, mono and bihydroxylation of the parent molecule, loss of benzene moiety and/or propynylic chain. All these structures are easily degraded themselves, so that the only species recognised to endure in the investigated times is guanidine. A mechanism of transformation accounting for the identified intermediates is proposed.

Headspace solid phase micro extraction (HS–SPME) was used for extraction of aroma compounds characterizing a Piedmont wine ( Ruche ) derived from a non aromatic vine. Extracted compounds were identified by ion trap mass spectrometry (ITMS) after gas-chromatographic analysis. In this way a selection of 59 identified primary aromatic compounds, related to the typical flavour of Ruche was made possible. The SPME technique showed peculiar behaviour in that 23 of the 59 compounds identified were not detected by liquid-liquid solvent extraction of the same samples. Subsequent comparison with the aromatic profiles of different wine samples obtained by microvinification from different grape varieties showed similarities between Ruche and the wines, Brachetto and Malvasia , originating from aromatic vines. SPME analysis proved to be useful in understanding aroma compositions of all samples examined, establishing bases for further investigations on the chemical and biochemical mechanisms underlying wine aroma development.

The photolysis of folic acid (=N-(4-{[(2-amino-1,4-dihydro-4-oxopteridin-6-yl)methyl]amino}benzoyl)-L-glutamic acid) in alkaline aqueous solution (pH 10.0–11.0) was carried out at 350 nm at room temperature and monitored by UV/VIS spectrophotometry, anal. and prep. thin-layer chromatography (TLC), and high-performance liquid chromatography (HPLC, HPLC/MS). The folate species underwent at least two independent photo-oxidation pathways, which were not observed when the acid form was photolyzed at pH

HPLC/UV–VIS diode array and HPLC/MS techniques were successfully applied to the analysis of sulfonated molecules present in samples coming from the photocatalytic degradation of the azo dye indicator, methyl orange. The substrate was chosen as a simple model for the study of reactions involving the more complex commercial products used for the dyeing of textile fibers. Unexpected MS fragmentation path was observed, due to the very stable methyl orange molecular structure. The chromatographic information were combined with the obtained MS, MS/MS data and the UV–VIS diode array spectra and allowed to rationalize the molecular structures attributable to the various degradation products.

Tebuconazole is a widely used fungicide. The formation of by-products on irradiated titanium dioxide as a photocatalyst was evaluated. Several species derived from tebuconazole degradation were identified and characterized by HPLC/MSn. A pattern of reactions accounting for the observed intermediates is proposed. Different parallel pathways are operating (and through these pathways the transformation of the molecule proceeds), leading to a wide range of intermediate compounds. All these molecules are more hydrophylic than tebuconazole. The main steps involved are (1) the hydroxylation of the molecule with the formation of three species having [M + H]+ 324; the hydroxylation occurs on the C-1 carbon and on the aromatic ring in the two ortho-positions; (2) the cleavage of a C—C bond with the release of the tert-butyl moiety and the formation of a species having m/z 250; analogously to step 1, also on this species a further hydroxylation reaction occurs; (3) through the loss of the triazole moiety with the formation of a structure with m/z 257. Copyright © 2002 John Wiley & Sons, Ltd.

Completing a series of works begun by Wiener [34], Paley and Wiener [28] and Ingham [9], a far-reaching generalization of Parseval"s identity was obtained by Beurling [4] for nonharmonic Fourier series whose exponents satisfy a uniform gap condition. Later this gap condition was weakened by Ullrich [33], Castro and Zuazua [5], Jaffard, Tucsnak and Zuazua [11] and then in [2] in some particular cases. In this paper we prove a general theorem which contains all previous results. Furthermore, applying a different method, we prove a variant of this theorem for nonharmonic Fourier series with vector coefficients. This result, partly motivated by control-theoretical applications, extends several earlier results obtained in [15] and [2]. Finally, applying these results we obtain an optimal simultaneous observability theorem concerning a system of vibrating strings.

Experiments were designed to demonstrate the actual contribution of yeast in the formation of the primary aroma during the vinification of neutral grapes. Ruché was chosen as the model wine to study because of its unique fragrance. A yeast strain specific for Ruché was selected using a new and rapid isolation method for red wines. The results of this study can be summarized as follows: Skins from nonaromatic white or red grapes apparently contain most of the primary aroma compounds that are revealed in the must only after contact with yeast cells under defined conditions. Similar results were obtained with the pulp and seeds fractions; however, the olfactory notes, although well characterized, differed from those obtained with skins alone. Clarification, filtration, and centrifugation of the pulp and seed fractions or sonification of the skins produce different and well-characterized olfaction notes during the contact with yeast. The primary aroma of nonaromatic white and red grapes contained in the skins can be revealed within 24-48 h of yeast contact in a synthetic nutrient medium (SNM). The primary aroma precursors extracted from the skins with methanol, water-saturated butanol, or aqueous buffer at pH 3.2, concentrated and eluted from a C18 resin column, can be transformed to the free form wine aroma markers within 6 h of contact with yeast cells in SNM. By contrast, prolonged maceration of the skins in aqueous alcoholic buffer at pH 3.2 or 1.1, at 50 or 70 degrees C did not release primary odors typical of wine. The individual primary aroma compounds, identified by GC-MS analysis in Ruché wine samples or in Ruché skin-yeast-SNM samples, could not explain the complexity of the typical Ruché wine odor. Only odors common to many wine varieties were identified by GC-olfactometry analysis.

Many researches have demonstrated that the use of biological processes in the production of drinking water has many advantages over conventional alternatives. One possibility is that biological processes will result in lower levels of genotoxic by-products in the drinking water. This possibility was investigated in the present study, which compares the levels of such by-products following either chemical or biological treatments. Water samples, collected at the main steps of the two key stages of both treatments were passed over XAD2/8 resins, to concentrate micropollutants, included by-products, for subsequent analysis using the microsome/Salmonella assay (TA98 and TA100±S9). The results showed that biological treatment, avoiding break-point chlorination, limits by-product formation and associated mutagenic generation. It follows that, in this respect, biological processes seem to have significant advantages over conventional water treatments.

Resume Suivant des travaux classiques de Paley, Wiener et Ingham, Beurling a generalise l'identite de Parseval aux series de Fourier non harmoniques dont les exposants sont uniformement discrets. Motives par des problemes en theorie du controle, cette derniere hypothese etait recemment affaiblie par Castro, Jaffard, Tucsnak et Zuazua dans des cas particuliers. Generalisant une autre methode, due a Kahane, on obtient un theoreme general qui contient tous les resultats anterieurs. Son efficacite est illustree par des applications a la theorie du controle.

The determination of toxic components from fire gases is difficult because the environment is hot, reactions are often temperature dependent, and a lot of soot may be produced. Due to the different properties of the gas components, a different time-consuming procedure for each species has traditionally been used. The use of FTIR (Fourier transform infrared) spectrometers as a continuous monitoring technique overcomes many of the problems in smoke gas analyses. FTIR offers an opportunity to set up a calibration and prediction method for each gas showing a characteristic spectral band in the infrared region of the spectrum. The objective of the SAFIR project was to further develop the FTIR gas analysis of smoke gases to be an applicable and reliable method for the determination of toxic components in combustion gases related to fire test conditions. The optimum probe design, filter parameters and the most suitable sampling lines in terms of flow rate, diameter, construction material and operating temperature have been specified. In the large scale, special concern was given to the probe design and the effects of the probe location as well as practical considerations of the sampling line length. Quantitative calibration and prediction methods have been constructed for different components present in smoke gases. Recommendations on how to deal with interferents, non-linearities and outliers have been provided and a verification method for the spectrometer for unexpected variations and for the different models have been described. FTIR measurement procedures in different fire test scenarios have been studied using the recommendations of this project for measurement techniques and analysis and an interlaboratory trial of the FTIR technique in smoke gas analysis was carried out to define the repeatability and reproducibility of the method in connection with a small scale fire test method, the cone calorimeter. Copyright © 2000 John Wiley & Sons Ltd.

Resume Dans [4] Ingham a ameliore un resultat precedent de Wiener [10] sur les series de Fourier non harmoniques. En modifiant sa fonction de poids nous obtenons des resultats optimaux, ameliorant plusieurs theoremes anterieurs de Kahane [7], Ullrich [9], Castro et Zuazua [2] et de Jaffard, Tucsnak et Zuazua [5]. Ensuite on donne une application aux problemes d'observabilite simultanee.

The many effects of the African medicinal herb Desmodium adscendens were studied in the 1980s and 1990s. In spite of this, a comprehensive analytical protocol for the quality control of its constituents (soyasaponins, alkaloids and flavonoids) has not yet been formulated and reported. This study deals with the optimization of extraction conditions from the plant and qualitative identification of the constituents by HPLC–diode array UV and multistage mass spectrometry. Plant constituents were extracted from leaves by liquid–liquid and solid matrix dispersion extraction. Separation was achieved via RP-C18 liquid chromatography with UV and MSn detection and mass spectrometry analysis was conducted by electrospray ionization ion trap or orbitrap mass spectrometry. High resolution mass spectrometry (HRMS) was used for structural identification of active molecules relating to soyasaponins and alkaloids. The flavonoid fragmentations were preliminarily studied by HRMS in order to accurately characterize the more common neutral losses. However, the high number of isomeric species induced us to make recourse to a more extended chromatographic separation in order to enable useful tandem mass spectrometry and ultraviolet spectral interpretation to propose a reasonable chemical classification of these polyphenols. 35 compounds of this class were identified herein with respect to the five reported in literature. In this way we made up a comprehensive protocol for the qualitative analysis of the high complexity content of this plant. This result paves the way for both reliable quality control of potential phytochemical medicaments and possible future systematic clinical studies.

The photochemical transformation of N,N-diethyl-m-toluamide (DEET), one of the most widespread and efficient mosquito repellents, has been investigated. Initially, photoinduced DEET degradation was investigated in liquid samples, at 20 °C and 0 °C, and in ice (−15 °C), aimed to simulate all possible photoinduced processes occurring in water and in cold environments. Under UV-illumination, DEET degradation was more efficient in ice than in water. The evaluation of transformation products (TPs) formed during the photolysis in solution and in ice evidences mostly the same degradation products, but with different concentration ratio and some peculiar differences. An hypothesis about what kind of processes may play a role is reported. In solution, the oxidative process mostly involved were (poly)hydroxylation or oxidation of the hydroxyl groups, while in ice N-dealkylation and monohydroxylation prevail. Finally, DEET and its TPs were searched out in snow and river water in wintertime.

In a very vivid way, the author describes how Magenes was introduced to the Dam Problem, and how the group around Magenes, made up by pure analysts, numerical analysts, mathematical physicists, worked hard to provide a solution that could be satisfactory both from a theoretical and practical point of view.

Phenolic compounds in bark extracts of seven different clones of poplar trees were analysed by RP-HPLC with diode-array UV detection. The chromatographic results obtained were treated by means of chemometric methods to highlight any pattern in the data allowing one to discriminate poplars in terms of resistance to the fungus Discosporium populeum. The phenolic compounds turned out to be more related to the genetic origin of the clones than to their resistance.