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1.
Anal Chim Acta ; 613(1): 31-9, 2008 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-18374699

RESUMO

Lavandin, a sterile hybrid of Lavandula angustifolia P. Mill. x Lavandula latifolia (L.f.) Medikus (Lamiaceae) is a plant widely cultivated for essential oil production in the South of France. Chemometric treatment by mid-infrared (MID-IR) spectroscopy data was assessed for the differentiation of Grosso Lavandin Essential Oils of Controlled Area (GLEOCA) and results were compared to those obtained by gas chromatography for MID-IR short time technique validation. The quantification of the main 13 hydrocarbons and oxygenated compounds generally controlled by industrial perfumers in GLEOCA samples (n=83) of three geographic origins: "Simiane", "Puimoisson" (with two producers) and "Richerenches" and their classification were successfully obtained by partial least square discriminant analysis (PLS-DA) by comparison with gas chromatography. The best prediction results were obtained using first derivate spectral data in the 1800-700 cm(-1) range. The spectroscopic interpretation of regression vectors showed that each geographic origin was correlated to components of GLEOCA. Chemometric MID-IR spectra treatments allowed us to obtain similar results than those obtained by time consuming analytical techniques such as GC and therefore constitute a robust and help fast method for authentication of GLEOCA and should be extended to other essential oils for authentication of geographic origin.


Assuntos
Óleos Voláteis/química , Cromatografia Gasosa , Análise dos Mínimos Quadrados , Óleos Voláteis/análise , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Lipids ; 38(1): 85-8, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12669824

RESUMO

Two tunicates (Eudistoma bituminis and Cystodytes violatinctus, family Polycitoridae) were investigated for the FA content of their phospholipids. GC-MS analysis of their methyl esters and N-acyl pyrrolidides revealed 40 FA in E. bituminis, and 26 in C. violatinctus. In both cases, the most abundant FA were the saturated ones (C10 to C18). Cystodytes violatinctus contained considerable oleic acid (20%). Both E. bituminis and C. violatinctus contained phytanic acid and delta10-unsaturated FA, which had not previously been found in such organisms. The two tropical tunicates contained only trace amounts of PUFA, which are usually predominant in this phylum.


Assuntos
Ácidos Graxos/análise , Fosfolipídeos/química , Urocordados/química , Animais , Ácidos Graxos Insaturados/análise , Cromatografia Gasosa-Espectrometria de Massas , Oceano Índico
3.
J Agric Food Chem ; 48(10): 4728-33, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11052725

RESUMO

Phlorin (3,5-dihydroxyphenyl beta-D-glucopyranoside), an orange peel marker, has been searched in 45 species and varieties of Citrus. The phlorin content was determined by high-pressure liquid chromatography in juices and aqueous peel extracts of these different fruits. The phlorin content in C. reticulata peel extract varies from 0 to 1012 mg L(-)(1) with a mean of 162 mg L(-)(1). On the contrary, phlorin was not found in mandarin and clementine juices except for mandarin "Commune" and "Beauty" (33 and 30 mg L(-)(1), respectively). In the 14 species of oranges and varieties, phlorin was detected in juices and peel extracts with a mean of 22 and 492 mg L(-)(1), respectively, while for grapefruits, means were 108 mg L(-)(1) in juices and 982 mg L(-)(1) for peel extracts. Tangors and tangelos which are hybrids (C. reticulata x C. sinensis and C. reticulata x C. paradisi, respectively) are characterized by the systematic presence of phlorin in peels (mean: 406 and 659 mg L(-)(1), respectively) while in juices its presence could be variable (0-73 mg L(-)(1)). These heterogeneity and values may be explained by the genetic variability of these hybrids and the phlorin content of their parentage group.


Assuntos
Citrus/química , Floroglucinol/análise , Porfirinas , Bebidas/análise , Floroglucinol/análogos & derivados , Especificidade da Espécie
4.
J Agric Food Chem ; 48(10): 4739-43, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11052727

RESUMO

Analysis of the neutral lipids from Vanilla fragrans and Vanilla tahitensis (Orchidaceae) without saponification resulted in the isolation and identification of a new product family in this plant: beta-dicarbonyl compounds. The compound structures are composed of a long aliphatic chain with 2,4-dicarbonyl carbons and a cis double bond at the n-9 position. They represent approximately 28% of the neutral lipids, that is, 1.5%, in immature beans, and approximately 10% of the neutral lipids, that is, 0.9%, in mature beans. Using retention indices, gas chromatography-mass spectrometry, derivatization reactions, and chemical degradation, five beta-dicarbonyl compounds have been identified including 16-pentacosene-2,4-dione, 18-heptacosene-2,4-dione, 20-nonacosene-2, 4-dione, 22-hentriacontene-2,4-dione, and 24-tritriacontene-2, 4-dione. Among them (Z)-18-heptacosene-2,4-dione, or nervonoylacetone, has been synthesized in two steps starting from nervonic acid. The major constituent, nervonoylacetone, represented 74.5% of the beta-dicarbonyl fraction. The range of these compounds has been studied in relation with bean maturity for V. fragrans and V. tahitensis species. This compound family has not been found in the leaves or stems of any of the three vanilla species studied and is markedly absent in the beans of V. madagascariensis.


Assuntos
Cetonas/análise , Cetonas/síntese química , Plantas/química , Ceras/análise , Cromatografia Gasosa-Espectrometria de Massas , Cetonas/química , Cetonas/isolamento & purificação , Espectrofotometria Ultravioleta
5.
J Agric Food Chem ; 47(8): 3202-5, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10552631

RESUMO

Analyses of the neutral lipids from Vanilla species before saponification resulted in the identification of a new product family in this genus: long-chain gamma-pyrone compounds with an aliphatic chain containing a cis double bond at the n-9 position. These compounds represent 7-8% of the neutral lipids in mature beans. Using NMR and gas chromatography/mass spectrometry, three gamma-pyrones have been identified, including 2-(10-nonadecenyl)-2, 3-dihydro-6-methyl-4H-pyran-4-one, 2-(12-heneicosenyl)-2, 3-dihydro-6-methyl-4H-pyran-4-one, and 2-(14-tricosenyl)-2, 3-dihydro-6-methyl-4H-pyran-4-one. The major constituent was 2-(14-tricosenyl)-2,3-dihydro-6-methyl-4H-pyran-4-one, which represented 70.3% of the gamma-pyrone fraction. The variability of this compound family has been studied in relation to bean maturity in V. fragrans and V. tahitensis beans. This compound family has not been found either in leaves or in stems or in V. madagascariensis beans.


Assuntos
Pironas/química , Sementes/química , Ceras/química , Aromatizantes , Estrutura Molecular , Pironas/isolamento & purificação , Especificidade da Espécie
6.
J Agric Food Chem ; 47(3): 968-76, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10552400

RESUMO

The carotenoid pigment profiles of authentic pure orange juices from Spain and Florida and an industrial paprika (Capsicum annuum) extract used for food coloring were obtained using reversed-phase liquid chromatography with a C18 packed column and an acetone/methanol/water eluent system. The procedure involving the carotenoid extraction is described. Both retention times and spectral properties using photodiode array detection for characterization of the major carotenoids at 430 and 519 nm are given. The influence of external addition of tangerine juice and/or paprika extract on orange juice color is described using the U.S. Department of Agriculture scale and adulterated orange juice. The procedure for quantitation of externally added paprika extract to orange juice is investigated, and the limit of quantitation, coefficient of variation, and recoveries are determined.


Assuntos
Bebidas/análise , Capsicum , Carotenoides/análise , Citrus , Corantes de Alimentos/análise , Extratos Vegetais , Plantas Medicinais , Florida , Espanha
7.
J Agric Food Chem ; 47(10): 4038-45, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10552762

RESUMO

Pure Valencia orange (Citrus sinensis) juices (64 samples) from Spain, Israel, Belize, Cuba, and Florida, harvested during two seasons (1996-1997 and 1997-1998), were analyzed for their carotenoid profiles. The detection of saponified carotenoid pigments has been achieved and quantitated using a photodiode array detection monitored at 350, 430, and 486 nm. Carotenoid pigments commonly found in the orange variety Valencia have been separated on a polymeric C-30 column using a ternary gradient as eluent. Pure Valencia juices from oranges grown in Mediterranean regions (Israel and Spain) have a high carotenoid content, expressed in beta-carotene (5-18 and 14-35 mg L(-)(1), respectively), compared to those grown in tropical and subtropical regions (Cuba, Belize, and Florida) (4-10, 2-8, and 5-10 mg L(-)(1), respectively). Quantitative results allowed the differentiation of Valencia variety geographical origins, in particular, the Mediterranean area from tropical and subtropical areas, using multidimensional analyses of carotenoid contents.


Assuntos
Bebidas , Carotenoides/análise , Citrus/química , Citrus/normas , Belize , Cromatografia Líquida , Cor , Cuba , Florida , Israel , Espanha
8.
J Agric Food Chem ; 47(10): 4175-7, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10552786

RESUMO

Three hydroquinone compounds have been isolated from the Indian Ocean tunicate Aplidium savignyi. Two are already known: geranylhydroquinone and the 2-(3-hydroxy-3,7-dimethyloct-6-enyl)-1,4-benzenediol as a new stereoisomer 2-(2Z)-(3-hydroxy-3, 7-dimethyloct-2,6-dienyl)-1,4-benzenediol. The structures were determined using spectroscopic data ((1)H NMR, (13)C NMR, MS, UV, and IR). These compounds are potential natural antioxidants.


Assuntos
Antioxidantes/química , Hidroquinonas/química , Urocordados , Animais , Antioxidantes/isolamento & purificação , Hidroquinonas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Espectrofotometria Infravermelho , Espectrofotometria Ultravioleta
9.
J Agric Food Chem ; 47(11): 4645-8, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10552864

RESUMO

A survey of compositional characteristics of the aerial part of sheep's burnet (Sanguisorba minor ssp. muricata) growing in Mediterranean French pastures has been undertaken. Investigations with scanning electron microscopy gave the morphological structure of this plant, in particular for akene ornamentation. Taxonomic characters confirmed the identification of the muricata subspecies. Moisture, ash, free sugars, cellulose, amino acids, and fatty acids of the whole aerial part were determined. Besides the major component, cellulose (20.4%), amino acid analysis showed that proteins contained mainly glutamic acid plus glutamine (0.67%) and aspartic acid plus asparagine (0.56%). The main fatty acids were palmitic (29.1%), linoleic (22.6%), and linolenic (21.4%).


Assuntos
Ração Animal , Poaceae/ultraestrutura , Animais , Microscopia Eletrônica de Varredura , Valor Nutritivo , Ovinos
10.
J Agric Food Chem ; 47(10): 4038-45, Oct. 1999.
Artigo em Inglês | MedCarib | ID: med-741

RESUMO

Pure Valencia orange (Citrus sinensis) juices (64 samples) from Spain, Israel, Belize, Cuba, and Florida, harvested during two seasons (1996-1997 and 1997-1998), were analyzed for their carotenoid profiles. The detection of saponified carotenoid pigments has been achieved and quantified using a photodiode array detection monitored at 350, 430, and 486 nm. Carotenoid pigments commonly found in the orange variety Valencia have been separated on a polymeric C-30 column using a ternary gradient as eluent. Pure Valencia juices from oranges grown in the Mediterranean regions (Israel and Spain) have a high carotenoid content, expressed in beta-carotene (5-18 and 14-35 mg L(-)(1), respectively), compared to those grown in tropical and subtropical regions (Cuba, Belize, and Florida) (4-10, 2-8, and 5-10 mg L(-)(1), respectively). Quantitative results allowed the differentiation of Valencia variety geographical origins, in particular, the Mediterranean area from tropical and subtropical areas, using multidimensinal analyses of carotenoid contents. (AU)


Assuntos
Estudo Comparativo , Bebidas , Carotenoides/análise , Citrus/química , Citrus/normas , Belize , Cromatografia Líquida , Cor , Cuba , Florida , Israel , Espanha
11.
Steroids ; 63(11): 575-8, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9830683

RESUMO

Three new 9,11-secosterols, 3 beta,6 alpha,11-trihydroxy-9,11-seco-5 alpha-cholest-7-ene-9-one (1), 24S- (2a), and 24R-methyl-3 beta,6 alpha, 11-trihydroxy-9,11-seco-5 alpha-cholest-7,22E-diene-9-one (2b), were isolated from the Indian Ocean gorgonia, Subergorgia suberosa. Their structures were established by spectroscopic data.


Assuntos
Cnidários/química , Esteróis/isolamento & purificação , Animais , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrofotometria Ultravioleta , Esteróis/química
12.
J Chromatogr A ; 800(2): 171-9, 1998 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-9561761

RESUMO

We present a simultaneous liquid chromatographic method for the separation of two flavonoid compound families, flavanone glycosides (FGs) and polymethoxylated flavones (PMFs), which are usually found in citrus fruits species and varieties. This technique permits the quantitation of six FGs (narirutin, naringin, hesperidin, neohesperidin, didymin, poncirin) and six PMFs (sinensetin, hexamethoxyflavone, nobiletin, scutellarein, heptamethoxyflavone and tangeretin). This technique, to be used to characterize a citrus juice by its polyphenolic profile, has been applied to the determination of flavonoid compounds in grapefruit- and orange juice. Differentiation of orange juice varieties and mixtures containing tangor juice using polyphenolic profiles and flavonoid content has been achieved.


Assuntos
Bebidas/análise , Cromatografia Líquida de Alta Pressão/métodos , Citrus/química , Flavanonas , Flavonoides/análise , Flavonoides/química , Fenóis/química , Polímeros/química , Reprodutibilidade dos Testes
13.
J Nat Prod ; 60(7): 700-3, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9249974

RESUMO

Three new triterpenes, sodwanones M, K, and L (4, 5, 6), together with three known sodwanones (A, B, and D) have been isolated from the sponge Axinella weltneri from the Comoros Islands, in the Indian Ocean. The three new structures were determined by interpretation of NMR spectra and, in the case of sodwanone K, also by oxidation to the known sodwanone D. Sodwanone M, the major isolated compound, was found to be cytotoxic to P-388 murine leukemia cells at a concentration of 1 microgram/mL.


Assuntos
Antineoplásicos/isolamento & purificação , Poríferos/química , Triterpenos/isolamento & purificação , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Leucemia P388/patologia , Espectroscopia de Ressonância Magnética , Triterpenos/química , Triterpenos/farmacologia
14.
Free Radic Biol Med ; 20(1): 35-43, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8903677

RESUMO

The antioxidant properties of 24 hydroxy-flavones were evaluated. Results show that 2',3',4'-OH substitution on the B ring plays a crucial role in radical scavenger activity in the DPPH assay and in the inhibitory effect on pereoxydation of tissue lipids in the MDA test. The formation of stable radicals for this type of compounds has been studied by ESR. In addition, it has been found that 7-hydroxy-flavones are potent competitive inhibitors of xanthine oxidase. It is proposed that the C-7 OH of flavones may take the place of the C-2 or C-6 OH of xanthine in the active site of the enzyme. A C-4' OH or C-4' OMe substitution on the 7-hydroxy flavones is not favourable to a fit in the active site. The 2',3',4'-trihydroxy-flavones inhibited XO by another process, which remains to be determined. In summary, this study provides evidence that hydroxy-flavones exhibit interesting antioxidant properties expressed either by the capacity to scavenge free radicals (for 2',3',4'-trihydroxy-flavones) or to competitively inhibit xanthine oxidase (for 7-hydroxy-flavones). These compounds may be drug candidates for treating pathologies related to free radical oxidation.


Assuntos
Antioxidantes/farmacologia , Flavonoides/farmacologia , Sequestradores de Radicais Livres/farmacologia , Picratos , Antioxidantes/metabolismo , Benzoquinonas/química , Benzoquinonas/metabolismo , Bepridil/análogos & derivados , Bepridil/metabolismo , Sítios de Ligação , Compostos de Bifenilo , Espectroscopia de Ressonância de Spin Eletrônica , Flavonoides/química , Flavonoides/metabolismo , Sequestradores de Radicais Livres/metabolismo , Radicais Livres/metabolismo , Cinética , Peroxidação de Lipídeos/efeitos dos fármacos , Medições Luminescentes , Estrutura Molecular , Espectrofotometria Ultravioleta , Substâncias Reativas com Ácido Tiobarbitúrico , Xantina Oxidase/antagonistas & inibidores , Xantina Oxidase/metabolismo
15.
Food Chem Toxicol ; 33(5): 377-82, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7759021

RESUMO

The effects on drug metabolizing enzymes of cyclopropenoid fatty acids present in baobab seed oil were evaluated in rats fed either a diet with baobab seed oil (1.27% cyclopropenoid fatty acids in the diet) or a diet with heated baobab seed oil (0.046% cyclopropenoid fatty acids in the diet). Comparison was made with rats fed a mixture of oils that contained no cyclopropenoid fatty acid. Rats fed baobab oil showed retarded growth. In comparison with the other groups, the relative liver weights were markedly increased whereas cytochrome P-450 content and NADPH cytochrome c reductase and NADH cytochrome c reductase activities were decreased. In rats fed the heated baobab oil the relative liver weight was decreased and the cytochrome P-450 level and reductase activities were increased relative to levels in rats fed the unheated oil. Ethoxycoumarin deethylase, ethoxyresorufin deethylase and pentoxyresorufin depentylase activities, expressed on the basis of cytochrome P-450, were greater in the group fed unheated baobab seed oil. Cytosolic glutathione transferase activity was markedly decreased in rats fed fresh baobab seed oil and heating the oil, which reduced the content of cyclopropenoid fatty acids, led to a considerable increase of this activity. UDP-glucuronyl transferase activities were not modified by the type of oil included in the diet. It is possible that the mechanisms of action of cyclopropenoid fatty acids are related to alterations of membrane lipid composition or microsomal proteins.


Assuntos
Ciclopropanos/toxicidade , Fígado/efeitos dos fármacos , Fígado/enzimologia , Óleos de Plantas/toxicidade , Análise de Variância , Animais , Citosol/efeitos dos fármacos , Citosol/enzimologia , Ácidos Graxos/toxicidade , Feminino , Temperatura Alta , Masculino , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/enzimologia , Distribuição Aleatória , Ratos , Ratos Wistar , Árvores
16.
Lipids ; 30(5): 459-66, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7637567

RESUMO

Fatty acids from total lipids of the gorgonian Leptogorgia piccola (white and yellow morphs), collected from the same area at two different periods with regard to the average water temperature, were studied. More than fifty fatty acids were identified as methyl esters and N-acyl pyrrolidides by gas chromatography and gas chromatography/mass spectrometry. Three new, branched-chain unsaturated fatty acids were identified in addition to the unusual 7-methyl-6-hexadecenoic acid, namely 10-methyl-6-hexadecenoic, 7,9-dimethyl-6-hexadecenoic, and 10-methyl-6,9-heptadecadienoic acids. Also 6,9-heptadecadienoic acid was identified. The fatty acid patterns of specimens harvested in colder waters were quite different from those harvested in warmer waters in that the former contained high amounts of methylene-interrupted polyunsaturated acids, including tetracosapolyenoic acids, especially 6,9,12,15,18-24:5 (up to 15.8% of the total acid mixture) and 6,9,12,15,18,21-24:6 (up to 5.3%). Arachidonic acid was, nevertheless, a major component in all the fatty acid mixtures studied (13.6-20.5%). Based on gas chromatography/Fourier transform infrared experiments, the double bonds were assigned the (Z) configuration. Several fatty aldehydes and their dimethyl acetals were also detected, of which the most abundant was octadecanal.


Assuntos
Cnidários/química , Ácidos Graxos/química , Animais , Cromatografia Gasosa , Cromatografia Gasosa-Espectrometria de Massas , Lipídeos/química , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
17.
Steroids ; 59(3): 181-4, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8048149

RESUMO

The Senegalese sponge Microscleroderma spirophora has been found to produce exclusively very unusual 3 beta-methoxysteroids in place of the common 3 beta-hydroxysteroids. Six different methoxysteroids (three of which are novel compounds) have been isolated and identified by spectroscopic means (MS, IR, 1H and 13C NMR), and their taxonomic significance discussed. A new method for the determination of the configuration at C-24 in saturated 24-ethyl side chains is also proposed.


Assuntos
Poríferos/química , Esteroides/isolamento & purificação , Animais , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Estrutura Molecular , Espectrofotometria Infravermelho , Esteroides/química
18.
J Chromatogr ; 634(1): 129-34, 1993 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-8486744

RESUMO

Six flavone glycosides were separated by HPLC using RP-18 with a quaternary mobile phase mixture [water-acetonitrile-tetrahydrofuran-acetic acid (80:16:3:1, v/v)]. This procedure was applied to the separation and determination of the most important flavanone glycosides contained in pure grapefruit and sour orange juices and mixtures. This method can be used for quality control of industrial concentrates and juices.


Assuntos
Bebidas/análise , Citrus/química , Flavanonas , Flavonoides/isolamento & purificação , Sequência de Carboidratos , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Hesperidina/análise , Hesperidina/isolamento & purificação , Dados de Sequência Molecular , Controle de Qualidade
19.
J Chromatogr ; 329(2): 231-46, 1985 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-4030975

RESUMO

A partial separation of nine sterol acetates and seven triterpene alcohol acetates by reversed-phase liquid chromatography is described. Good results are obtained using acetonitrile-water (90:10, v/v) as mobile phase with an UV detector at 205 nm. The variation in sterol sensitivity shows that this technique is not suitable for quantitative analyses. A combination of this technique for the fractionation of the natural sterol mixture, gas-liquid chromatography for quantitation and gas chromatography-mass spectrometry for identification is necessary for the determination of sterol compounds contained in natural products. An example of the separation, identification and quantitation of sterol acetates from sunflower seed oil is given.


Assuntos
Esteróis/análise , Triterpenos/análise , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Helianthus/análise , Indicadores e Reagentes , Óleos/análise , Sementes/análise , Espectrofotometria Ultravioleta
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