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1.
Am J Clin Nutr ; 118(5): 1010-1019, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37640108

RESUMEN

BACKGROUND: In Greece, nearly a third of savory baked goods (SBGs) exceeded the limit of 2 g of nonruminant or industrial trans fatty acids (i-TFA) per 100 g fat in 2015. The impact of the Commission Regulation (European Union) 2019/649 on exposure to trans fatty acids (TFA), i-TFA, and saturated fatty acid (SFA) from SBGs has not been previously evaluated. OBJECTIVES: The study aimed to explore fatty acid reformulation of SBG products and assess differences in TFA, i-TFA, and SFA intakes using a sample of Greek SBG consumers from a nationally representative survey. METHODS: In 2021, 140 samples of SBGs were collected in the greater metropolitan area of Athens, and their fat profile and content were compared to those from 2015. Based on these measurements, food consumption substitution models were employed to examine TFA and SFA intake differences, and the percent contribution from SBG among consumers was calculated (N = 1008). Nutrient densities were calculated by adjusting all fat intakes by individual mean energy intake (percentage of daily total energy intake). RESULTS: The 2% i-TFA legislative limit/100 g of fat in measured SBGs was exceeded by 11.4% in 2021 compared to 31.1% in 2015 (19.7% increase in compliance). Median i-TFA and TFA intakes from SBGs were reduced from 0.05 (0.01, 0.12)% and 0.13 (0.03, 0.27)% in 2015 to 0.03 (0.01, 0.09) and 0.06 (0.03, 0.13)% in 2021, respectively. In terms of SFA, a mean increase/100 g was calculated, resulting in an increased intake in 2021 compared to 2015 [5.18% (2.78, 8.37) and 3.55 (1.99, 5.73), respectively]. CONCLUSIONS: Despite the reductions seen in i-TFA content of SBGs, food product reformulation efforts in Greece should focus not only on TFA content but also on SFA reduction to improve public health.


Asunto(s)
Ácidos Grasos , Ácidos Grasos trans , Humanos , Grecia , Grasas de la Dieta , Ingestión de Energía
2.
Molecules ; 27(4)2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35209139

RESUMEN

Extra virgin olive oil (EVOO) is a key component of the Mediterranean diet, with several health benefits derived from its consumption. Moreover, due to its eminent market position, EVOO has been thoroughly studied over the last several years, aiming at its authentication, but also to reveal the chemical profile inherent to its beneficial properties. In the present work, a comparative study was conducted to assess Greek EVOOs' quality and authentication utilizing different analytical approaches, both targeted and untargeted. 173 monovarietal EVOOs from three emblematic Greek cultivars (Koroneiki, Kolovi and Adramytiani), obtained during the harvesting years of 2018-2020, were analyzed and quantified as per their fatty acids methyl esters (FAMEs) composition via the official method (EEC) No 2568/91, as well as their bioactive content through liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS) methodology. In addition to FAMEs analysis, EVOO samples were also analyzed via HRMS-untargeted metabolomics and optical spectroscopy techniques (visible absorption, fluorescence and Raman). The data retrieved from all applied techniques were analyzed with Machine Learning methods for the authentication of the EVOOs' variety. The models' predictive performance was calculated through test samples, while for further evaluation 30 commercially available EVOO samples were also examined in terms of variety. To the best of our knowledge, this is the first study where different techniques from the fields of standard analysis, spectrometry and optical spectroscopy are applied to the same EVOO samples, providing strong insight into EVOOs chemical profile and a comparative evaluation through the different platforms.


Asunto(s)
Análisis de los Alimentos , Calidad de los Alimentos , Aceite de Oliva/química , Aceite de Oliva/normas , Ácidos Grasos/análisis , Análisis de los Alimentos/métodos , Ingredientes Alimentarios/análisis , Grecia , Metabolómica/métodos , Análisis Espectral
3.
Mol Divers ; 22(1): 11-19, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28936770

RESUMEN

A synthesis of functionalized 4,5-bis(phenylimino)-1,3-thiazolidine-2-ylidenes via a simple reaction between ketene [Formula: see text]-acetals (derived from isothiocyanates and acetonitrile derivatives) with N,[Formula: see text]-diphenyloxalimidoyl dichloride in the presence of KOH in DMF is described. When CS[Formula: see text] was used as the heterocumulene component, the reaction led to the formation of 4,5-bis(phenylimino)-1,3-dithiolan-2-ylidene derivatives, in moderate to good yields.


Asunto(s)
Acetales/química , Técnicas de Química Sintética , Etilenos/química , Cetonas/química , Tiazolidinas/síntesis química , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Estructura Molecular
4.
Chemosphere ; 92(4): 399-405, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23399310

RESUMEN

Olive mill wastewater (OMW) generated during the oil extraction from Olea europea L. var. koroneiki olives was sampled at the beginning, the middle and the end of the harvesting season for three successive crop production years, and from four olive mills. OMW samples were examined in respect to their physicochemical characteristics, fatty acid composition of the lipid fraction, and adverse effects on biomass production of nine white-rot fungi of the basidiomycetous genus Pleurotus. Total N, nitrogen species, potassium and phosphate concentrations as well as total phenolics content of OMW samples were influenced by the crop year but not from the harvest period (albeit higher values for nitrate, nitrite, phosphate and potassium as well as total phenolics contents were obtained during ripening of olives), whereas protein concentration, total organic carbon and total solids were not significantly affected by the crop year or the harvest period. In addition, fatty acids composition, i.e. nC14:0, nC16:1Δ9cis, nC17:1Δ10cis, nC18:0, nC18:1Δ9cis, nC22:0 and nC24:0 varied significantly during different crop years and harvest periods. Olive fruits maturity and biannual alternate-bearing appear to play key-roles in the fatty acid variation detected in OMW samples. OMW toxicity as evaluated by the mycelium growth of Pleurotus strains was influenced significantly by the phenolic content of OMW samples obtained during three successive crop years; in contrast, the olives harvest period did not affect Pleurotus biomass production. Hence, experimental data indicated that selected Pleurotus strains could serve as bioindicators of OMW toxicity. Development of viable OMW detoxification processes as well as the exploitation of the effluent's fertilizing value are discussed in the light of the above findings.


Asunto(s)
Olea/química , Pleurotus/metabolismo , Aguas Residuales/química , Biodegradación Ambiental , Biomasa , Ácidos Grasos/química , Residuos Industriales , Nitrógeno/metabolismo , Fenoles/metabolismo , Fosfatos/metabolismo , Pleurotus/efectos de los fármacos , Potasio/metabolismo , Eliminación de Residuos Líquidos , Contaminantes Químicos del Agua/metabolismo , Contaminantes Químicos del Agua/toxicidad
5.
Chem Commun (Camb) ; 49(10): 1008-10, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23250355

RESUMEN

Three 2D and 3D photoreactive MOFs of trans,trans-muconic acid with Er(3+) and their corresponding isomorphous Y(3+) phases were synthesized and their photoreactivity was studied as a function of the crystal environment.


Asunto(s)
Elementos de la Serie de los Lantanoides/química , Compuestos Organometálicos/química , Ácido Sórbico/análogos & derivados , Modelos Moleculares , Compuestos Organometálicos/síntesis química , Procesos Fotoquímicos , Ácido Sórbico/química
6.
J Org Chem ; 77(23): 10949-54, 2012 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-23157313

RESUMEN

The reaction of ß-dicarbonyl phenyliodonium ylides with diphenylketene at room temperature affords mixtures of lactone and aurone derivatives. The initial electrophilic attack of the iodonium ylide on the C(ß) position of the diphenylketene, followed by cyclization of the zwitterionic species, and subsequent ejection of iodobenzene, affords the lactone and aurone cycloadducts. Treatment of ß-dicarbonyl iodonium ylides with acyl chlorides yields α-chloroenones with good to excellent yields.

7.
Chem Commun (Camb) ; 47(25): 7140-2, 2011 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-21614352

RESUMEN

The assembly of Er(3+) and Y(3+) cations with trans,trans-muconic acid affords a photoreactive 3D microporous MOF that, upon UV irradiation, undergoes a cycloaddition reaction (SCSC up to 55%), with in situ formation of a strained ladderane.

8.
Inorg Chem ; 46(4): 1187-95, 2007 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-17291115

RESUMEN

Organotin(IV) complexes with the formulas [(C6H5)3Sn(mbzt)] (1), [(C6H5)3Sn(cmbzt)] (3), and [(C6H5)2Sn(cmbzt)2] (4) (Hmbzt = 2-mercaptobenzothiazole and Hcmbzt = 5-chloro-2-mercaptobenzothiazole) have been synthesized and characterized by elemental analysis; FT-IR, Raman, 1H, 13C, and 119Sn NMR, and Mössbauer spectroscopic techniques; and X-ray crystallography at various temperatures. The crystal structures of complexes 1, 3, and 4 were determined by X-ray diffraction at room temperature [295(1) or 293(2) K]. The complexes [(C6H5)3Sn(mbzo)] (2) and [(n-C4H9)2Sn(cmbzt)2] (5) (Hmbzo = 2-mercaptobenzoxazole) were synthesized by new improved methods, and their structures were determined at low temperature [100(1) K] and compared to those solved at room temperature. Comparison with {(CH3)2Sn(cmbzt)2]} (6), already reported, was also attempted. The influence of temperature on the geometry of the complexes is discussed. In the cases of complexes 1-3, three carbon atoms from phenyl groups and one sulfur atom and one nitrogen atom from thione ligands form a tetrahedrally distorted trigonal-bipyramidal geometry around the five-coordinate tin(IV) ion. In complexes 4-6, two carbon atoms from aryl groups and two sulfur atoms and two nitrogen atoms from thione ligands form a distorted tetrahedral geometry, tending toward octahedral, around the six-coordinate tin(IV) ions, with trans-C2, cis-N2, and cis-S2 configurations. Although the C-Sn and S-Sn bond distances are found to be constant in compounds 1-6, their N-Sn bond lengths vary significantly (from 2.635 to 3.078 A), with the longer distances found in the cases of five-coordinate complexes 1-3.


Asunto(s)
Benzotiazoles/química , Compuestos Orgánicos de Estaño/síntesis química , Antifúngicos/química , Benceno/química , Carbono/química , Cloro/química , Cristalografía por Rayos X , Ligandos , Nitrógeno/química , Análisis Espectral , Estereoisomerismo , Azufre/química , Temperatura , Tioamidas/química
9.
Photochem Photobiol Sci ; 4(6): 469-80, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15920631

RESUMEN

The photochemistry of three structurally very similar triphenylmethylsilanes 1, 2, 3 [p-X-C(6)H(4)-CPh(2)-SiMe(3): X = PhCO, 1; H, ; Ph(OCH(2)CH(2)O)C, 3] is described by means of 248 and 308 nm nanosecond laser flash photolysis (ns-LFP), femtosecond LFP, EPR spectroscopy, emission spectroscopy (fluorescence, phosphorescence), ns-pulse radiolysis (ns-PR), photoproduct analysis studies in MeCN, and X-ray crystallographic analysis of the two key-compounds 1 and 2. The photochemical behavior of 1, 2 and 3 is discussed and compared with that of a fourth one, 4, bearing on the p-position an amino group (X = Me(2)N) and whose detailed photochemistry we reported earlier (J. Org. Chem., 2000, 65, 4274-4280). Silane 1 undergoes on irradiation with 248 and 308 nm laser light a fast photodissociation of the C-Si bond giving the p-(benzoyl)triphenylmethyl radical (1*) with a rate constant of k(diss)= 3 x 10(7) s(-1). The formation of 1* is a one-quantum process and takes place via the carbonyl triplet excited state with high quantum yield (Phi(rad)= 0.9); the intervention of the triplet state is clearly demonstrated through the phosphorescence spectrum and quenching experiments with ferrocene (k(q)= 9.3 x 10(9) M(-1) s(-1)), Et(3)N (1.1 x 10(9) M(-1) s(-1)), and styrene (3.1 x 10(9) M(-1) s(-1)) giving quenching rate constants very similar to those of benzophenone. For comparative reasons radical 1* was generated independently from p-(benzoyl)triphenylmethyl bromide via pulse radiolysis in THF and its absorption coefficient at lambda(max)= 340 nm was determined ([epsilon]= 27770 M(-1) cm(-1)). We found thus that the p-PhCO-derivative 1 behaves similar to the p-Me(2)N one (the latter giving the p-(dimethylamino)triphenylmethyl radical with Phi(rad)= 0.9), irrespective of their completely different ground state electronic properties. In contrast, compounds 2, 3 that bear only the aromatic chromophore give by laser or lamp irradiation both, (i) radical products [Ph(3)C* and p-Ph(OCH(2)CH(2)O)C-C(6)H(4)-C(*)Ph(2), respectively] after dissociation of the central C-Si bond (Phi(rad)= 0.16), and (ii) persistent photo-Fries rearrangement products (of the type of 5-methylidene-6-trimethylsilyl-1,3-cyclohexadiene) absorbing at 300-450 nm and arising from a 1,3-shift of the SiMe(3) group from the benzylic to the ortho-position of the aromatic ring (Phi approximately 0.85 for 2). Using fs-LFP on 2 we showed that the S(1) state recorded at 100 fs after the pulse decays on a time scale of 500 fs giving Ph(3)C* through C-Si bond dissociation. In a second step and within the next 10 ps trityl radicals either escape from the solvent cage (the quantum yield of Ph(3)C* formation Phi(rad)= 0.16 was measured with ns-LFP), or undergo in-cage recombination to photo-Fries products. Thus, singlet excited states (S(1)) of the aromatic organosilanes (2, 3) prefer photo-Fries rearrangement products, while triplet excited states (1, 4) favor free radicals. Both reactions proceed via a common primary photodissociation step (C-Si bond homolysis) and differentiate obviously in the multiplicity of the resulting geminate radical pairs; singlet radical pairs give preferably photo-Fries products following an in-cage recombination, while triplet radical pairs escape the solvent cage (MeCN). The results demonstrate the crucial role which is played by the chromophore which prescribes in a sense, (i) the multiplicity of the intervening excited state and consequently that of the resulting geminate radical pair, and (ii) the dominant reaction path to be followed: the benzophenone- and anilino-chromophore present in silanes 1 and 4, respectively, impose effective intersystem crossing transitions (k(isc)= 10(11) s(-1) and 6 x 10(8) s(-1), respectively) leading to triplet states and finally to free radical products, while the phenyl chromophore in 2 and 3, possessing ineffective isc (k(isc)= 6 x 10(6) s(-1)) leads to photo-Fries product formation via the energetic high lying S(1) state [approximately 443 kJ mol(-1)(106 kcal mol(-1))].


Asunto(s)
Silanos/química , Termodinámica , Cristalografía por Rayos X , Radicales Libres/química , Radicales Libres/efectos de la radiación , Rayos Láser , Mediciones Luminiscentes , Modelos Moleculares , Estructura Molecular , Fotoquímica , Fotólisis , Silanos/efectos de la radiación , Rayos Ultravioleta
10.
Chem Commun (Camb) ; (21): 2418-9, 2004 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-15514794

RESUMEN

We describe the synthesis, crystal structure and solid state reactivity of cadmium fumarate dihydrate, which is made up of planar H-bonded metal-organic layers and undergoes, upon irradiation, a topochemical [2 + 2] cycloaddition reaction.


Asunto(s)
Cadmio/química , Fumaratos/química , Compuestos Organometálicos , Cristalografía por Rayos X , Ciclización/efectos de la radiación , Enlace de Hidrógeno , Modelos Moleculares , Estructura Molecular , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/química , Compuestos Organometálicos/efectos de la radiación , Fotoquímica , Temperatura
11.
J Inorg Biochem ; 98(2): 358-64, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14729316

RESUMEN

The synthesis and characterization of copper(II) complexes with a potent non-steroidal anti-inflammatory drug, tolfenamic acid, Htolf, with formula [Cu(tolf)(2)L](2) (where L is H(2)O or DMF, N,N-dimethylformamide) were investigated. The crystal and molecular structure of [Cu(tolf)(2)(DMF)](2) was reported. Crystallographic data are as follows: monoclinic system, space group P2(1)/n with cell constants a=9.068(2) A, b=14.514(3) A, c=22.826(4) A, V=2948.9(10) A(3) and Z=2. The crystal structure consists of binuclear, quadruply bridged neutral molecule with a Cu-Cu bond length of 2.6075(19) A. The complex is self-assembled via C-H-pi intermolecular stacking interactions. Spectroscopic and electrochemical studies were reported. The superoxide dismutase activity is measured and compared with those of superoxide dismutase enzyme, SOD, the free ligand and related copper complexes with non-steroidal anti-inflammatory drugs, NSAIDs. IC(50) value was measured by the Fridovich test (1.97+/-0.17 microM), which showed that [Cu(tolf)(2)L](2) is a good superoxide scavenger.

12.
Appl Spectrosc ; 57(4): 407-12, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-14658637

RESUMEN

Fourier transform (FT) Raman spectroscopy based on band intensity or band area measurements was used for the quantitative determination of acyclovir in pharmaceutical solid dosage forms through their poly(vinyl chloride) blister package. Univariate calibration using the bands observed at 1690, 1630, 1574, 1482, 1181, 578, and 508 cm(-1) was found to be sufficient for the analysis. Calibration curves were linear, the correlation coefficients being 0.997-0.9993 and 0.996-0.9991 for band intensity and band area measurements, respectively. Results obtained compare well, as indicated by the t-test, with those obtained by the current United States Pharmacopoeia (USP 24) and National Formulary (NF 19) method. Precision ranged from 0.7-4.5 and 0.4-4.0% RSD (n = 3) for band intensity and band area measurements, respectively. The developed nondestructive FT-Raman method is rapid, simple, and can be used for the on-line, real-time monitoring of acyclovir formulation production lines.


Asunto(s)
Aciclovir/análisis , Seguridad de Productos para el Consumidor , Embalaje de Medicamentos/métodos , Almacenaje de Medicamentos , Preparaciones Farmacéuticas/análisis , Cloruro de Polivinilo , Espectrometría Raman/métodos , Aciclovir/química , Embalaje de Medicamentos/normas , Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/normas , Farmacopeas como Asunto , Polvos , Control de Calidad , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Espectrometría Raman/normas , Comprimidos , Estados Unidos
13.
J Inorg Biochem ; 96(2-3): 425-34, 2003 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-12888279

RESUMEN

Five new organotin(IV) molecules with the heterocyclic thioamides; 2-mercaptobenzothiazole (Hmbzt), 5-chloro-2-mercaptobenzothiazole (Hcmbzt), 3-methyl-2-mercaptobenzothiazole (mmbzt) and 2-mercaptonicotinic acid (H(2)mna) of formulae [(n-C(4)H(9))(2)Sn(mbzt)(2)] (1), [(C(6)H(5))(2)Sn(mbzt)(2)] (2), [(CH(3))(2)Sn(cmbzt)(2)].1.7(H(2)O)] (3), [(n-C(4)H(9))(2)SnCl(2)(mmbzt)(2).(CH(2)Cl(2))] (4) and [[(C(6)H(5))(3)Sn](2)(mna).[(CH(3))(2)CO]] (5) have been synthesized and characterized by elemental analysis, 1H-, 13C-NMR, FT-IR and Mössbauer spectroscopic techniques. Crystal structures of molecules 1, 3 and 5 have been determined by X-ray diffraction at 173(1) K (1 and 5) and 293(2) K (3). Compound 1 C(22)H(26)N(2)S(4)Sn, is monoclinic, space group C2/c, a=44.018(2), b=8.8864(5), c=12.8633(7) A, beta=104.195(5) degrees, Z=8. Compound 3 is also monoclinic, space group P2(1)/c and a=17.128(2) A, b=17.919(2) A, c=7.3580(10) A, beta=98.290(10) degrees, Z=4. In both molecules 1 and 3, two carbon atoms from aryl groups, two sulfur and two nitrogen atoms from thione ligands form a distorted octahedral geometry around tin(IV) with trans-C(2), cis-N(2), cis-S(2) configurations. Compound 5 C(45)H(39)NO(3)SSn(2) is monoclinic, space group P2(1)/n, a=9.1148(2) A, b=29.2819(6), c=15.5556(4) A, beta=106.2851(9) degrees, Z=4. Complex 5 contains two [(C(6)H(5))(3)Sn(IV)] moieties linked by a double deprotonated 2-mercaptonicotinic acid (H(2)mna). Both tin(IV) ions are five coordinated. This complex is the an example of a pentacoordinated Ph(3)SnXY system with an axial-equatorial arrangement of the phenyl groups at Sn(1) atom. Compounds 1, 3 and 5 were tested for in vitro cytotoxicity against the cancer cell line of sarcoma cells (mesenchymal tissue) from the Wistar rat, polycyclic aromatic hydrocarbons (benzo[a]pyrene) carcinogenesis. Compound 5 exhibits strong cytotoxic activity, while complexes 1 and 3 show less cytotoxic activity.


Asunto(s)
Antineoplásicos/síntesis química , Compuestos Orgánicos de Estaño/síntesis química , Sarcoma/tratamiento farmacológico , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Benzo(a)pireno , Supervivencia Celular/efectos de los fármacos , Cristalografía por Rayos X , Estructura Molecular , Ácidos Nicotínicos/química , Ácidos Nicotínicos/farmacología , Compuestos Orgánicos de Estaño/química , Compuestos Orgánicos de Estaño/farmacología , Ratas , Ratas Wistar , Sarcoma/inducido químicamente , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/química , Compuestos de Sulfhidrilo/farmacología , Tiazoles/química , Tiazoles/farmacología , Tioamidas/química , Tioamidas/farmacología
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