Liquid chromatography quadrupole time-of-flight mass spectrometry quantification and screening of organophosphate compounds in sludge.

For the first time, we assess the performance of liquid chromatography (LC) quadrupole time-of-flight (QTOF) mass spectrometry (MS) for the selective quantification of eight organophosphate compounds (OPs), used as plasticizers and flame retardants additives, in sludge from urban sewage treatment plants (STPs). Moreover, the usefulness of accurate, full scan MS and MS/MS spectra to screen and to confirm the presence of additional OPs, without using reference standards, in sludge samples is discussed. Matrix solid-phase dispersion (MSPD) was used as a sample preparation technique. Under optimized conditions, MSPD provided quantitative recoveries for the group of targeted analytes, requiring just 15 mL of solvent and integrating extraction and clean-up processes in the same step. For these species, the achieved limits of quantification (LOQs) varied between 2 and 50 ng g(-1) and the efficiency of electrospray ionization (ESI) did not change significantly between pure standards and sludge extracts. Among targeted OPs, tri(chloroisopropyl) phosphate (TCPP), tributoxyethyl phosphate (TBEP) and triphenyl phosphate (TPP) were ubiquitous in sludge. The average concentrations of TCPP and TBEP stayed above 700 ng g(-1), whereas the mean value for TPP was 67 ng g(-1). Full scan, accurate spectra provided relevant clues for the screening of additional OPs, using a database containing just their empirical formulae and exact molecular weights; however, the occurrence of in-source fragmentation processes hampered the detection and correct identification of those species which did not render the expected [M+H](+) molecular ion, as was the case of 2-ethylhexyl-diphenyl phosphate (EHDPP).

Characterization of volatile fraction of typical Irpinian wines fermented with a new starter yeast.

Non-Saccharomyces yeasts are microorganisms that play an important role in the fermentation dynamics, compositions and flavour of wine. The aromatic compounds responsible for varietal aroma in wine are mainly terpenes, of which the most important group are the monoterpenes because of their volatility and odour if present in a free form. In fact, some terpenyl-glycosides do not contribute to the aroma unless they are hydrolysed. The glycosylated form of terpenes can be converted by hydrolysis with ß-glycosidases produced by yeasts during the winemaking process, into aromatic compounds. In this study we utilized a non-Saccharomyces yeast, with a high extra-cellular glycosidase activity, isolated from grapes of cultivars typical of Irpinia region. This strain, identified as a Rhodotorula mucillaginosa (strain WLR12), was used to carry out an experimental winemaking process and the results were compared with those obtained with a commercial yeast starter. Chemical and sensorial analysis demonstrated that the wines produced with WLR12 strain had a more floral aroma and some sweet and ripened fruit notes compared to those obtained with commercial yeast. The data also showed an increasing of the free terpenes fraction that, however, did not significatively modify the bouquet of the wines.

HPLC separation and NMR structural elucidation of sn-1,2-, 2,3-, and 1,3-diacylglycerols from olive oil as naphthylethylurethane derivatives.

In this study, sn-1,2-, sn-2,3-, and sn-1,3-diacylglycerols were isolated from olive oil, and their urethane derivatives (urethanes) were prepared. Normal-phase high-performance liquid chromatography (NP-HPLC) separation of the urethane isomers was performed and the separate classes were studied by nuclear magnetic resonance (NMR). The use of 1H NMR and homo- and heteronuclear 2D techniques provided a great amount of information in a very short time, particularly when a high-field NMR instrument (700 MHz) was used. Particularly diagnostic for this kind of compound was the glyceridic moiety that presents typical chemical shifts both for carbon and hydrogen. These studies show the usefulness of NMR spectroscopy to recognize clearly the sn-1,3- and, moreover, sn-1,2- with respect to sn-2,3-diacylglycerols, although very minor differences occur between them.

The effect of isoquinoline alkaloids on opiate withdrawal.

Our interest has been centered on isoquinoline alkaloids obtained from Argemone mexicana (Papaveraceae), Aristolochia constricta (Aristolochiaceae) and the opium alkaloid, papaverine. In this respect, the effect of these isoquinoline alkaloids was investigated on contractions induced by naloxone of isolated guinea pig ileum acutely exposed to morphine in vitro. The activity of these alkaloids was compared to the control compound, papaverine. Furthermore, the effect of these isoquinoline alkaloids was also determined on naloxone-precipitated withdrawal in isolated guinea pig ileum exposed to DAMGO (highly selective mu opioid receptor agonist) and U50-488H (highly selective kappa opioid receptor agonist) to test whether the possible interaction of isoquinoline alkaloids on opioid withdrawal involves mu- and/or kappa-opioid receptors. Isoquinoline alkaloids from A. mexicana (from 5 x 10(-6) to 1 x 10(-4) M), from A. constricta (1 x 10(-5) x 10(-5)-1 x 10(-4) M) as well as papaverine treatment (1 x 10(-7)-5 x 10(-6)-1 x 10(-6) M) before or after the opioid agonists were able of both preventing and reversing the naloxone-induced contraction after exposure to mu (morphine and DAMGO) or kappa (U50-488H) opiate receptor agonists in a concentration-dependent manner. Both acetylcholine response and electrical stimulation were also reduced by isoquinoline alkaloids and papaverine treatment as well as the final opiate withdrawal was still reduced. The results of the present study indicate that isoquinoline alkaloids as well as papaverine were able to produce significant influence on the opiate withdrawal in vitro and these compounds were able to exert their effects both at mu and kappa opioid agonists.

Anti-HIV activity of dibenzylbutyrolactone-type lignans from Phenax species endemic in Costa Rica.

Previously, we isolated two new dibenzylbutyrolactone-type lignans, named phenaxolactones and, from the leaves of Phenax angustifolius Wedd. (Urticaceae). In this investigation three new dibenzylbutyrolactone lignans (phenaxolactones), together with phenaxolactone, and flavones vitexin, isovitexin, were isolated from Phenax rugosus Wedd. leaves collected in Santa Ana, Costa Rica. The structures were elucidated using 1D and 2D NMR spectroscopy as well as mass spectrometry. Phenaxolactones and flavones and were evaluated for their inhibitory activity against HIV-1MN in infected C8166 cells. The most promising compound was phenaxolactone with an EC50 value of 3.0 microM, no cytotoxicity at 112 microM and a therapeutic index value of 37.3.

Isolation and HPLC quantitative analysis of flavonoid glycosides from Brazilian beverages (Maytenus ilicifolia and M. aquifolium).

Aqueous infusions of Brazilian Maytenus leaves are used as beverages, foodstuffs, and phytomedicines. Previously, we isolated two new flavonoid tetrasaccharides from the infusion of Maytenus aquifolium leaves that showed antiulcer activity. In this investigation a new flavonoid tetrasaccharide, kaempferol-3-O-alpha-L-rhamnopyranosyl (1-->6)-O-[alpha-L-arabinopyranosyl (1-->3)-O-alpha-L-rhamnopyranosyl (1-->2)]-O-beta-D-galactopyranoside (3), was isolated, together with kaempferol tri- and disaccharides and quercetin trisaccharides from the aqueous infusion of Maytenus ilicifolia leaves. All structures were elucidated by ES-MS and NMR spectroscopic methods. The quantitative analysis of the flavonoid glycosides from Maytenus ilicifolia and M. aquifolium has been performed by HPLC.

Aristophenones A and B. A new tautomeric pair of polyisoprenylated benzophenones from Garcinia aristata.

A tautomeric pair of new isoprenylated benzophenones, aristophenone A (1a) and B (1b), have been isolated from Garcinia aristata fruits. Their structures has been determined using high-field 2D NMR techniques.

Furanocoumarins from the aerial parts of Dorstenia contrajerva.

A new glycosylated furanocoumarin, alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranosyl-bergaptol (1), has been isolated from Dorstenia contrajerva together with three known furanocoumarins, catechin and epicatechin. Their structures were established using high field 2D NMR techniques.

Phenolic constituents of Phenax angustifolius.

Fractionation of an ethanolic extract of the leaves of Phenax angustifolius has resulted in the isolation of two new lignans, 2-hydroxy-2-(3',4'-dihydroxyphenyl)methyl-3-(3' ',4' '-dimethoxyphenyl)methyl-gamma-butyrolactone (1) and 2-hydroxy-2-(4'-O-beta-D-glucopyranosyl-3'-hydroxyphenyl)methyl-3-(3' ',4' '-dimethoxyphenyl)methyl-gamma-butyrolactone (2), and three known compounds, vitexin, isovitexin, and quercetin 3-O-alpha-L-rhamnopyranoside. The structures of 1 and 2 were determined using spectroscopic methods.

Inhibition of nitric oxide synthase expression by a methanolic extract of Crescentia alata and its derived flavonols.

In order to validate the use of Crescentia alata (Bignoniaceae) in the traditional medicine of Guatemala as an antiinflammatory remedy, the methanolic (MeOH) extract has been evaluated in vivo for antiinflammatory activity on carrageenin paw edema in rats and in vitro on Escherichia coli lipopolysaccharide- (LPS)-induced nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) expression in J774.A1 macrophage cell line. This extract exerted in vivo a significant anti-inflammatory activity at the highest dose tested. The same extract showed in vitro an inhibitory activity on inducible nitric oxide synthase expression and on NO formation in LPS-primed J774.A1 cells. Subsequent fractionation and analysis of the extract has led to the isolation and characterization as major constituents of two flavonol glycosides: quercetin 3-O-alpha-L-rhamnopyranosyl-(1->6)-beta-D-glucopyranoside (rutin) 1, kaempferol 3-O-alpha-L-rhamnopyranosyl-(1->6)-beta-D-glucopyranoside (kaempferol 3-O-rutinoside) 2, and flavonol aglycone, kaempferol 3. Their structures were elucidated by spectral methods. The bioassay-directed analysis of flavonols 1-3 indicated that kaempferol (3) was the most active compound contained in the MeOH extract because it reduced in vitro both NO production and iNOS expression in LPS-primed J774.A1 cells, whereas rutin (1) and kaempferol 3-O-rutinoside (2) showed no significant activity. The MeOH extract and all of flavonoids tested did not show in vitro significant cytotoxic effect in J774.A1 macrophage cell line.

New protopine alkaloids from Aristolochia constricta reduce morphine withdrawal in vitro.

The present study examines the effect of four new protopine alkaloids (1-4) isolated and purified from the aerial parts of Aristolochia constricta (Aristolichiaceae) on morphine withdrawal in vitro. The results of our experiments indicate that the pure compounds (1-4) significantly and in a concentration-dependent manner reduced the morphine withdrawal. The results of the present study suggest that these new protopine alkaloids may be potential anti-addictive agents.

Tropane alkaloids from the leaves and stem bark of Erythroxylon alaternifolium and Erythroxylon rotundifolium.

A novel 3alpha,6beta,7beta-triol tropane alkaloid esterified by two benzoyl residues was isolated from the leaves of the endemic cuban species, Erythroxylon alaternifolium. Another novel 3alpha,6alpha,7beta-triol tropane alkaloid esterified by trimethoxycinnamoyl and trimethoxybenzoyl residues was isolated from the leaves and stem bark of a second endemic cuban species, Erythroxylon rotundifolium. Their structures were elucidated as 3alpha,7beta-dibenzoyloxy-6beta-hydroxy-tropane and 3alpha-(3,4,5-trimethoxycinnamoyloxy)-7beta-(3,4,5- trimethoxybenzoyloxy)-6alpha-hydroxy-tropane by spectroscopic methods including 2D-NMR techniques.

Isolation and structure elucidation of two new flavonoid glycosides from the infusion of maytenus aquifolium leaves. Evaluation of the antiulcer activity of the infusion.

Droplet countercurrent chromatography and high-performance liquid chromatography fractionation of the aqueous infusion from Maytenus aquifolium Martius leaves afforded two flavonoid tetrasaccharides: quercetin 3-O-alpha-L-rhamnopyranosyl(1-->6)-O-[beta-D-glucopyranosyl(1-->3)-O- alpha-L-rhamnopyranosyl(1-->2)-O-beta-D-galactopyranoside and kaempferol 3-O-alpha-L-rhamnopyranosyl(1-->6)-O-[beta-D-glucopyranosyl(1-->3)-O- alpha-L-rhamnopyranosyl(1-->2)-O-beta-D-galactopyranoside. All structures were elucidated by spectroscopic methods. Pharmacological essays of the infusion showed antiulcer activity in rats.

Studies on the constituents of Gliricidia sepium (Leguminosae) leaves and roots: isolation and structure elucidation of new triterpenoid saponins and aromatic compounds.

Our research program on the Central American fooder plant Gliricidia sepium led to the discovery of two new triterpene saponins (1 and 2) and known aromatic compounds. The new compounds possess 3beta,21beta, 24-trihydroxy-22-oxoolean-12-ene as an aglycon. The oligosaccharide moiety linked to C-3 of the aglycon contained two pyranoses (glucuronic acid and xylose); in addition the glucose residue of both 1 and 2 is also linked to C-21. Structure elucidation of these new compounds through the extensive use of 1D and 2D NMR techniques have provided detailed information about the sapogenin and the saccharide chains, inclusive of sugar sequence and the position of glycosylation.

A polyisoprenylated benzophenone from Cuban propolis.

A novel polyisoprenylated benzophenone (1) has been isolated from an ethanol extract of Cuban propolis. Its structure has been determined using high-field 2D NMR techniques. Compound 1 showed significant antimicrobial and antifungal activity against a variety of bacteria and yeasts.

New naphthopyranone glycosides from Paepalanthus vellozioides and Paepalanthus latipes.

Three new compounds-3, 4-dihydro-10-hydroxy-7-methoxy-3-(R)-methyl-1H-3,4-dihydronaphtho- ]2, 3c]-pyran-1-one-9-O-beta-D-glucopyranoside (1), 3, 4-dihydro-10-hydroxy-7-methoxy-3-(R)-methyl-1H-3,4-dihydronaphtho- [2, 3c]-pyran-1-one-9-O-beta-D-glucopyranosyl-(1-->6)-glucopyranoside (2), and 3,4-dihydro-10-dihydroxy-7-methoxy-3-(R)-methyl-1H-3, 4-dihydronaphtho-[2,3c]-pyran-1-one-9-O-beta-D-allopyranosyl (1-->6)glucopyranoside (3)-were isolated from the leaves of Paepalanthus vellozioides and Paepalanthus latipes and characterized by spectrometric methods, mainly electrospray mass spectrometry and 1D and 2D NMR experiments. These unusual glycosylated dihydronaphthopyranones may serve as taxonomic markers of the genus Paepalanthus, since these compounds were not detected in other genera belonging to the Eriocaulaceae family.

New 3-methyoxyflavones, an iridoid lactone and a flavonol from duroia hirsuta

Investigation of the roots of Duroia hirsuta from Ecuador yielded the iridoid lactone duroin (1) together with 3,7,3', 5'-tetramethoxy-4'-hydroxyflavone (2), 3,7,3'-trimethoxy-4', 5'-dihydroxyflavone (3), and 7,3',5'-trimethoxy-3, 4'-dihydroxyflavone (4) as novel constituents.

New 12a-hydroxyrotenoids from gliricidia sepium bark

The investigation of a methanolic extract of Gliricidia sepium bark afforded, in addition to vestitol and 2'-O-methylvestitol, three new 12a-hydroxyrotenoids, gliricidol (1), 2-methoxygliricidol (2), and gliricidin (3). The structures of 1-3 were elucidated by analysis of their spectroscopic data. Compounds 1-3 exhibited activity against Artemia salina larvae.

Plants used in Guatemala for the treatment of protozoal infections: II. Activity of extracts and fractions of five Guatemalan plants against Trypanosoma cruzi.

The activities of crude plant extracts of five plants popularly used in Guatemala against bacterial and protozoal infections and some of their fractions have been evaluated against the trypomastigote and epimastigote forms of Trypanosoma cruzi in vitro. The most active fraction of Neurolaena lobata has also been screened in vivo. Main in vitro activities against trypomastigotes have been observed for the hexane and ethanol extracts of N. lobata (Asteraceae). Both extracts were also active against epimastigotes, whereas all other extracts tested had no effect on epimastigotes. For the hexane extracts of Petiveria alliacea (Phytolaccaceae) and Tridax procumbens (Asteraceae) a marked inhibition of trypomastigotes has been found. Also the ethanol extracts of Byrsonima crassifolia (Malpighiaceae) leafs and Gliricidia sepium (Papilionaceae) bark showed some trypanocidal activity. Fraction 2 of the ethanol extract of N. lobata was highly active against T. cruzi as well in vitro as in vivo. The chloroforme fraction of P. alliacea showed a high inhibition of trypomastigotes in vitro. Also three fractions of the active extract of B. crassifolia inhibited T. cruzi trypomastigotes. No fraction of G. sepium bark extract showed a marked trypanocidal activity.