Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Medicine (Baltimore) ; 101(38): e30713, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36197170

RESUMO

BACKGROUND: Here, we report the frequency of capsulated ampicillin-resistant Haemophilus influenzae strains isolated from children in Tunisia, particularly capsular serotype b, by polymerase chain reaction (PCR) to determine the molecular mechanisms underlying ampicillin resistance. METHODS: We considered 22 capsulated H influenzae strains selected from a series of 91 ampicillin-resistant H influenzae strains isolated from children between 2010 and 2011 in Tunisia. The capsular serotypes of these strains were identified by slide agglutination and PCR. RESULTS: By PCR, 19 (20.88%) serotype b, 1 (1.1%) serotype a, 2 (2.2%) serotypes d and f and 69 (75.82%) non-typeable strains were found among the 91 ampicillin-resistant H influenzae strains. 100% of the assumption between the consequences of antigenic examinations and PCR was found. The serotype b strains showed biotypes I, II, III, IV, VI, and VIII. The other capsulated strains showed biotypes IV and VIII. Thirteen of the serotype b strains created ß-lactamase (14.28%). The 19 serotype b ampicillin-resistant H influenzae strains were subdivided into 3 bunches as indicated: The gathering of the ß-lactamase positive, ampicillin-resistant where 11 strains (57.89%) were ß-lactamase positive blaTEM-1 (+) and ftsI (+). The second gathering of the ß-lactamase negative, ampicillin-resistant strains, where 6 isolates (31.58%) were ß-lactamase negative blaTEM-1 (-) and ftsI (-), and lastly, the gathering of the ß-lactamase positive, amoxicillin-clavulanate resistant where 2 isolates (10.52%) were ß-lactamase positive blaTEM-1 (+) and ftsI (-). CONCLUSION: PCR should be used in our country because it may contribute to decreasing the probability of transmission of these strains, especially those showing the two mechanisms of resistance among children in Tunisia.


Assuntos
Antibacterianos , Infecções por Haemophilus , Combinação Amoxicilina e Clavulanato de Potássio , Ampicilina/farmacologia , Resistência a Ampicilina , Antibacterianos/farmacologia , Criança , Infecções por Haemophilus/tratamento farmacológico , Infecções por Haemophilus/epidemiologia , Haemophilus influenzae/genética , Humanos , Testes de Sensibilidade Microbiana , beta-Lactamases
2.
Molecules ; 25(9)2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32384787

RESUMO

The Opuntia ficus indica (L.) (OFI) is used as a nutritional and pharmaceutical agent in various dietary and value added products. This study underlines the possible use of native prickly pear cladode powder as a functional ingredient for health-promoting food production. To summarise, chemical characterization of polyphenols, minerals and soluble dietary fibre was performed; furthermore, the antioxidant activity and bioaccessibility of polyphenols and minerals were assessed. Eleven compounds between phenolic acids and flavonoids were identified, with piscidic acid and isorhamnetin derivatives being the most abundant. Opuntia's dietary fibre was mainly constituted of mucilage and pectin, and was composed of arabinose, galactose, glucose, mannose, rhamnose, and xylose sugars. The polyphenols' bioaccessibility was very high: piscidic acid at 200%, eucomic and ferulic acids >110% and flavonoids from 89% to 100%. The prickly pear cladode powder is also a source of minerals, as cations (calcium, sodium, potassium and magnesium) and anions (sulphate and chloride), with high magnesium bioaccessibilty (93%). OFI powder showed good capacity of radical scavenging measured by DPPH and ABTS methods, with 740 and 775 µmol Trolox/100 g OFI, respectively. Finally, the presented results allow the consideration of this natural product as a source of several essential nutrients, with a possible use in the food industry as a functional ingredient.


Assuntos
Antioxidantes/análise , Fibras na Dieta/análise , Frutas/química , Micronutrientes/análise , Opuntia/química , Polifenóis/análise , Polissacarídeos/análise , Ânions/análise , Arabinose/análise , Benzotiazóis/química , Disponibilidade Biológica , Compostos de Bifenilo/química , Cátions/análise , Ácidos Cumáricos/análise , Flavonoides/análise , Galactose/análise , Glucose/análise , Hidroxibenzoatos/análise , Manose/análise , Minerais/análise , Pectinas/análise , Pectinas/isolamento & purificação , Picratos/química , Mucilagem Vegetal/análise , Mucilagem Vegetal/isolamento & purificação , Ramnose/análise , Ácidos Sulfônicos/química , Xilose/análise
3.
Am J Ther ; 24(6): e706-e712, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27058575

RESUMO

In this work, we characterized by high-performance liquid chromatography, the γ-tocopherol (573.66 µg/g), and by gas chromatography-mass spectrometry, the linoleic acid (62.05%) as major components from Peganum harmala L. seeds oil and evaluated their potential in vivo acute antiinflammatory, analgesic activities, and in vitro antioxidative capacity. The 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay showed an important antioxidant activity (62.50% with an IC50 of 4.8 mg/mL). In addition, the antiinflammatory effect of the formulation cream at 20% caused a reduction in inflammation at 5 hours after carrageenan application compared with diclofenac at 1% (60.4%; 45.65%; respectively). A slight potential peripheral analgesia was noted in plantar test in treated rats with cream (20 s). Therefore, our findings demonstrate that formulation cream of P. harmala seeds oil has an interesting antiinflammatory activity with a slight peripheral analgesic effect due mainly to its richness on linoleic acid, γ-tocopherol, and polyphenols and to its important antioxidant capacity.


Assuntos
Dermatite Atópica/tratamento farmacológico , Peganum/química , Extratos Vegetais/farmacologia , Óleos de Plantas/química , Sementes/química , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Carragenina/toxicidade , Cromatografia Líquida de Alta Pressão/métodos , Dermatite Atópica/induzido quimicamente , Modelos Animais de Doenças , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Ácido Linoleico/farmacologia , Masculino , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Creme para a Pele/farmacologia , gama-Tocoferol/farmacologia
4.
Biol Res ; 48: 7, 2015 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-25654423

RESUMO

BACKGROUND: In this paper, we have studied the essential oils chemical composition of the leaves of seven Eucalyptus species developed in Tunisia. Eucalyptus leaves were picked from trees growing in different arboretums in Tunisia. Choucha and Mrifeg arboretums located in Sedjnene, region of Bizerte (Choucha: E. maideni, E. astrengens et E. cinerea; Mrifeg : E. leucoxylon), Korbous arboretums located in the region of Nabeul, North East Tunisia with sub-humid bioclimate, (E. lehmani), Souiniet-Ain Drahem arboretum located in region of Jendouba (E. sideroxylon, E. bicostata). Essential oils were individually tested against a large panel of microorganisms including Staphylococcus aureus (ATCC 6539), Escherichia coli (ATCC 25922), Enterococcus faecalis (ATCC29212), Listeria ivanovii (RBL 30), Bacillus cereus (ATCC11778). RESULTS: The yield of essential oils ranged from 1.2% to 3% (w/w) for the different Eucalyptus species. All essential oils contain α-pinene, 1,8-cineol and pinocarveol-trans for all Eucalyptus species studied. The 1,8-cineol was the major compound in all species (49.07 to 83.59%). Diameter of inhibition zone of essential oils of Eucalyptus species varied from 10 to 29 mm. The largest zone of inhibition was obtained for Bacillus cereus (E. astrengens) and the lowest for Staphylococcus aureus (E. cinerea). The essential oils from E. maideni, E. astrengens, E. cinerea (arboretum of Bizerte), E. bicostata (arboretum of Aindraham) showed the highest antibacterial activity against Listeria ivanovii and Bacillus cereus. CONCLUSION: The major constituents of Eucalyptus leaves essential oils are 1,8-cineol (49.07 to 83.59%) and α-pinene (1.27 to 26.35%). The essential oils from E. maideni, E. astrengens, E. cinerea, E. bicostata showed the highest antibacterial activity against Listeria ivanovii and Bacillus cereus, they may have potential applications in food and pharmaceutical products.


Assuntos
Antibacterianos/farmacologia , Eucalyptus/química , Eucalyptus/classificação , Óleos Voláteis , Folhas de Planta/química , Bacillus cereus/efeitos dos fármacos , Monoterpenos Bicíclicos , Proliferação de Células/efeitos dos fármacos , Cicloexanóis/análise , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Eucaliptol , Cromatografia Gasosa-Espectrometria de Massas , Listeria/classificação , Listeria/efeitos dos fármacos , Monoterpenos/análise , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Tunísia
5.
J Sci Food Agric ; 95(10): 2028-32, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25214472

RESUMO

BACKGROUND: The search for other sources of vegetable oils by the exploitation and the enhancement of other oil plants will be needed to meet the demands of the international market. This study aims to determine the triacylglycerol (TAG) molecular species and aliphatic alcohol compositions of unexploited fruits of three Tunisian Pistacia lentiscus (lentisc) populations from the Korbous, Tebaba and Rimel areas of Tunisia. RESULTS: Results show that the content of total TAG varies from 738.32 mg g(-1) of total lipid in the Tebaba population to 981.15 mg g(-1) of total lipid in the Korbous population. Furthermore, 14 species of TAG were detected in the three studied populations. In addition, 13 aliphatic compounds were identified and classified into two groups: (1) aliphatic alcohols with fewer than 20 carbon atoms (hexadecanol, heptadecanol, (Z)-octadec-9-en-1-ol, octadecanol and nonadécanol); and (2) the policosanol group (eicosenol, docosenol, docosanol tetracosanol, hexacosanol octacosanol and triacontanol). The Tebaba population showed a distinct composition compared to Korbous and Rimel where heptadecanol is the major compound. CONCLUSION: Quantitatively, the most abundant TAG species are those constituted by palmitic, oleic and/or linoleic acid. Furthermore, the significant difference observed at the oil composition is associated with a remarkable station effect.


Assuntos
Álcoois/química , Frutas/química , Pistacia/química , Triglicerídeos/química , Análise de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Óleos de Plantas/química , Espectrometria de Massas por Ionização por Electrospray , Tunísia
6.
Food Chem ; 173: 972-8, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25466114

RESUMO

The aim of this work was to study the content of tocopherols, sterols, triterpenic and aliphatic alcohols, carotenoids, and volatile compounds in the kernel oils from six walnut (Juglans regia L.) varieties. The levels of ß-carotene ranged between 0.22 and 0.62 mg/kg, followed by lutein (0.01-0.06 mg/kg). The total content of tocopherol ranged from 186.5 to 436.2 mg/kg of the extracted oil and the major isoform in all samples was γ-tocopherol. The most abundant phytosterol was ß-sitosterol (974-1494 mg/kg) followed by campesterol then Δ-5-avenasterol. The major triterpenic alcohol was cycloartenol (226.4-532.1 mg/kg). Hexacosanol (9.71-28.15 mg/kg) was the major aliphatic alcohol. The detected volatile compounds were pentanal, hexanal, nonanal, 2-decenal and hexanol. The statistical analysis showed significant differences between varieties, which are probably due to genetic factors.


Assuntos
Carotenoides/análise , Juglans/química , Esteróis/análise , Tocoferóis/análise , Vitamina E/análise , Compostos Orgânicos Voláteis/análise , beta Caroteno/análise
7.
Biol. Res ; 48: 1-5, 2015. tab
Artigo em Inglês | LILACS | ID: lil-734620

RESUMO

BACKGROUND: In this paper, we have studied the essential oils chemical composition of the leaves of seven Eucalyptus species developed in Tunisia. Eucalyptus leaves were picked from trees growing in different arboretums in Tunisia. Choucha and Mrifeg arboretums located in Sedjnene, region of Bizerte (Choucha: E. maideni, E. astrengens et E. cinerea; Mrifeg : E. leucoxylon), Korbous arboretums located in the region of Nabeul, North East Tunisia with sub-humid bioclimate, (E. lehmani), Souiniet-Ain Drahem arboretum located in region of Jendouba (E. sideroxylon, E. bicostata). Essential oils were individually tested against a large panel of microorganisms includingStaphylococcus aureus (ATCC 6539), Escherichia coli (ATCC 25922), Enterococcus faecalis (ATCC29212), Listeria ivanovii (RBL 30), Bacillus cereus (ATCC11778). RESULTS: The yield of essential oils ranged from 1.2% to 3% (w/w) for the different Eucalyptus species. All essential oils contain α-pinene, 1,8-cineol and pinocarveol-trans for all Eucalyptus species studied. The 1,8-cineol was the major compound in all species (49.07 to 83.59%). Diameter of inhibition zone of essential oils of Eucalyptus species varied from 10 to 29 mm. The largest zone of inhibition was obtained for Bacillus cereus (E. astrengens) and the lowest for Staphylococcus aureus (E. cinerea). The essential oils from E. maideni, E. astrengens, E. cinerea (arboretum of Bizerte), E. bicostata(arboretum of Aindraham) showed the highest antibacterial activity against Listeria ivanovii and Bacillus cereus. CONCLUSION: The major constituents of Eucalyptus leaves essential oils are 1,8-cineol (49.07 to 83.59%) and α-pinene (1.27 to 26.35%). The essential oils from E. maideni, E. astrengens, E. cinerea, E. bicostatashowed the highest antibacterial activity against Listeria ivanovii and Bacillus cereus, they may have potential applications in food and pharmaceutical products.


Assuntos
Antibacterianos/farmacologia , Eucalyptus/química , Eucalyptus/classificação , Óleos Voláteis , Folhas de Planta/química , Bacillus cereus/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cicloexanóis/análise , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Listeria/classificação , Listeria/efeitos dos fármacos , Monoterpenos/análise , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Tunísia
8.
Nat Prod Res ; 28(24): 2293-300, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25103576

RESUMO

This study has determined oil, fatty acid (FA) and phytosterols content during the ripening of the Tunisian Onopordum acanthium L. seeds. In total, nine FAs and six phytosterols were identified. The main FAs were linoleic acid (0.18-8.06 mg/g of seed) followed by oleic acid (0.051-2.45 mg/g of seed), palmitic acid and stearic acid. Pentadecanoic acid was detected, for the first time, in unripe fruits and the two last stages of development were characterised by a relative abundance of erucic acid. Overall, ß-sitosterol (34.5-77.79% of total sterols) was the major 4-desmethylsterols during maturation. The first episodes of growth were characterised by the best amounts of stigmasterol and campesterol, while stigmastanol and Δ7 sitosterol had quoted the semi-ripe and fully ripe fruits; however, cholesterol was absent. These findings are useful in understanding a potential new source of important natural compounds (Phytosterols and USFA) found in this fruit and when harvest should be undertaken to optimise desired FA and phytosterols content.


Assuntos
Ácidos Graxos/análise , Frutas/química , Onopordum/química , Fitosteróis/análise , Óleos de Plantas/análise , Sementes/química , Colesterol/análogos & derivados , Colesterol/análise , Ácido Linoleico/análise , Ácido Oleico/análise , Onopordum/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Sitosteroides/análise , Estigmasterol/análise , Tunísia
9.
Food Chem ; 164: 309-16, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24996339

RESUMO

Changes in 4-desmethylsterol, 4-monomethylsterol, 4,4-dimethylsterol and phytostanol composition were quantitatively and qualitatively investigated during the ripening of three varieties of Tunisian-grown pecan nuts (Mahan, Moore and Burkett). These components have many health benefits, especially in lowering LDL-cholesterol and preventing heart disease. The phytosterol composition of whole pecan kernel was quantified by Gas Chromatography-Flame Ionisation Detection (GC-FID) and identified by Gas Chromatography-Mass Spectrometry (GC-MS). Fifteen phytosterols and one phytostanol were quantified. The greatest amount of phytosterols (2852.5mg/100g of oil) was detected in Mahan variety at 20 weeks after the flowering date (WAFD). Moore had the highest level of phytostanols (7.3mg/100g of oil) at 20 WAFD. Phytosterol and phytostanol contents showed a steep decrease during pecan nut development. Results from the quantitative characterisation of pecan nut oils revealed that ß-sitosterol, Δ5-avenasterol, and campesterol were the most abundant phytosterol compounds at all ripening stages.


Assuntos
Carya/química , Carya/crescimento & desenvolvimento , Nozes/química , Nozes/crescimento & desenvolvimento , Fitosteróis/análise , Óleos de Plantas/análise , Ionização de Chama , Cromatografia Gasosa-Espectrometria de Massas , Fitosteróis/química , Óleos de Plantas/química
10.
J Oleo Sci ; 63(7): 681-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24919478

RESUMO

Changes in the chemical composition and antioxidant activity of flaxseed hull during maturation were investigated. P129 hull variety was studied at four maturation stages (St1, St2, St3, and St4). Significant variation in proximate composition and flaxseed hull oil characteristics were observed. A significant increase in the carbohydrates content of the hull was observed during development. The main methyl esters were linolenic acid (48.95 - 51.52 %), oleic acid (20.27-23.41%) and linoleic acid (15.62-17.70%). The highest polyunsaturated fatty acids (PUFA) were found to be 67.14 % at the first stage of maturity (St1). Flaxseed hull oil was of good quality, containing an abundance of omega-3 essential fatty acids. The iodine value increased, while the saponification value of oil decreased during seed development. The decrease in ascorbic acid content was steady. The maximum level of total phenolic acid content (128.3 mg/100 g oil) was reached at 7 DAF. The antioxidant activity of oilseed was assessed by means of 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging assay. Radical scavenging activity for green hull was 52.74% and mature hull was 69.32%.


Assuntos
Antioxidantes/análise , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Insaturados/análise , Linho/química , Linho/crescimento & desenvolvimento , Óleo de Semente do Linho/química , Ácido Ascórbico/análise , Carboidratos/análise , Fenômenos Químicos , Sequestradores de Radicais Livres/análise , Hidroxibenzoatos/análise , Ácido Linoleico/análise , Ácido Oleico/análise , Ácido alfa-Linolênico/análise
11.
J Oleo Sci ; 63(1): 7-14, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24371194

RESUMO

Flaxseed has been used for centuries for oil extraction. In recent years it has attracted considerable interest as a result of studies which attribute potential health benefits to its components. Among the compounds that present biological activity, phenolic compounds are of special interest. The dietary lignan secoisolariciresinol diglucoside (SDG) reaches high concentrations in flaxseed. Flaxseed contains also other phenolic compounds, such as phenolic acids. Considering the importance of the phenolic fraction of flaxseed, high performance analytical methods have been developed to characterize its complex phenolic pattern. The understanding of the nature of these compounds is crucial for their possible exploitation in drugs and functional foods.


Assuntos
Linho/química , Fenóis/análise , Cromatografia Líquida de Alta Pressão , Eletroforese Capilar , Hidroxibenzoatos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Conformação Molecular , Fenóis/química , Fenóis/isolamento & purificação
12.
Biol Res ; 46(3): 257-63, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24346073

RESUMO

Fatty acid composition of peanut seed oil in four varieties cultivated in Tunisia showed that linoleic (C18:2), oleic (C18:1) and palmitic (C16) acids account for more than 84% for Chounfakhi and Massriya and for more than 85% of the total fatty acids of Trabilsia and Sinya seed oil respectively. Seed oil contents were significantly different (P ≤ 0.05) and did not exceed 48%. The study of total phenolics revealed that Chounfakhi contained more total phenolics (2.1 mg GAE/g DW), followed by the Massriya and Sinya cultivars (1.35 mg GAE/g DW for each); Trabilsia presented the lowest total phenolic content with 1 mg GAE/g DW. Considerable antiradical ability was found, especially in the Trabilsia peanut seed cultivar (IC50 = 1550 µg/ml), the Massriya and Sinya cultivars had, respectively, 720 and 820 mg/ml IC50. In the Massriya variety the sterol fraction showed antibacterial activity against Listeria ivanovii, Listeria inocua, Pseudomonas aeruginosa, Staphylococus aureus, Enterococcus hirae and Bacillus cereus.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Ácidos Graxos/análise , Fenóis/análise , Óleos de Plantas/farmacologia , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Ácidos Linoleicos/análise , Testes de Sensibilidade Microbiana , Ácido Oleico/análise , Ácido Palmítico/análise , Óleo de Amendoim , Óleos de Plantas/química , Sementes/química , Tunísia
13.
Biol. Res ; 46(3): 257-263, 2013. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-692192

RESUMO

Fatty acid composition of peanut seed oil in four varieties cultivated in Tunisia showed that linoleic (C18:2), oleic (C18:1) and palmitic (C16) acids account for more than 84% for Chounfakhi and Massriya and for more than 85% of the total fatty acids of Trabilsia and Sinya seed oil respectively. Seed oil contents were significantly different (P ≤ 0.05) and did not exceed 48%. The study of total phenolics revealed that Chounfakhi contained more total phenolics (2.1 mg GAE/g DW), followed by the Massriya and Sinya cultivars (1.35 mg GAE/g DW for each); Trabilsia presented the lowest total phenolic content with 1 mg GAE/g DW. Considerable antiradical ability was found, especially in the Trabilsia peanut seed cultivar (IC50 = 1550 μg/ml), the Massriya and Sinya cultivars had, respectively, 720 and 820 mg/ml IC50. In the Massriya variety the sterol fraction showed antibacterial activity against Listeria ivanovii, Listeria inocua, Pseudomonas aeruginosa, Staphylococus aureus, Enterococcus hirae and Bacillus cereus.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Ácidos Graxos/análise , Fenóis/análise , Óleos de Plantas/farmacologia , Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Ácidos Linoleicos/análise , Testes de Sensibilidade Microbiana , Ácido Oleico/análise , Ácido Palmítico/análise , Óleos de Plantas/química , Sementes/química , Tunísia
14.
Plant Physiol Biochem ; 54: 1-5, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22361130

RESUMO

The aim of the present research is to investigate the effect of harvest date on the composition of flaxseed. Samples were collected at regular intervals from 7 to 56 days after flowering (DAF) and analyzed for phospholipid composition, storage protein content and chemical properties. Phospholipid (PL) percentage of the total lipid decreased from 32.72% on the 7th DAF to 2.55% on the 56th DAF. The most phospholipids present in flaxseed were phosphatidylinositol (PI), phosphatidylethanolamine (PE) and lysophosphatidylcholine (LPC) which were highly unsaturated and rich in linolenic and linoleic acids, comprising together 60% of the total fatty acids. Chemical investigation of flaxseed oil showed overall a decrease in UV absorbance (K(232) and K(270)), acid value, free fatty acid content and an increase in peroxide value and storage protein content with development. At full maturity, flaxseed contained 29% proteins on a dry weight basis (DW %).


Assuntos
Agricultura/métodos , Ácidos Graxos/metabolismo , Linho/metabolismo , Óleo de Semente do Linho/metabolismo , Fosfolipídeos/metabolismo , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Linho/crescimento & desenvolvimento , Óleo de Semente do Linho/química , Peróxidos/metabolismo , Fosfolipídeos/química , Sementes/crescimento & desenvolvimento , Raios Ultravioleta
15.
Plant Physiol Biochem ; 49(7): 774-81, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21356594

RESUMO

Seven 4-desmethylsterols, five triterpene alcohols and three 4α-monomethylsterols were identified by GC-MS during the development of wild peanut, which is Arbi (AraA), and cultivars peanut, which are Trabelsia (AraT) and Chounfakhi (AraC). Our results showed that the maximum level of 4-desmethylsterols (881.07 mg/100 g of oil) was reached at 12 days after flowering (DAF) date of peanut plant in AraA, as well as the highest level of triterpene alcohols (31.51 mg/100 g of oil) was reached at 23 DAF in AraA, whilst, the highest level of 4α-monomethylsterols (15.11 mg/100 g of oil) was reached at 41 DAF in AraC. Herein, the level of triterpene alcohols and 4α-monomethylsterols was overwhelmed by the amount of 4-desmethylsterols at each stage of peanut maturity. Differences were observed in each sterol contents among the studied cultivars and wild one especially in immature stage.


Assuntos
Arachis/química , Fitosteróis/análise , Extratos Vegetais/química , Triterpenos/análise , Arachis/crescimento & desenvolvimento , Arachis/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Fitosteróis/metabolismo , Extratos Vegetais/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Fatores de Tempo , Triterpenos/metabolismo
16.
Food Chem ; 129(2): 437-442, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30634249

RESUMO

A high-performance liquid chromatographic method coupled with mass spectrometry was used to characterise the natural phospholipid (PL) classes and molecular species in flaxseed oils. The PL fraction included phosphatidylethanolamine (PE) (27-40%), phosphatidylinositol (PI) (29-32%), phosphatidylcholine (PC) (7-18%), lysophosphatidylcholine (LPC) (8-21%), phosphatidylglycerol (PG) (1-4%) and phosphatidic acid (PA) (1-9%). The distribution of fatty acids was found to differ between phospholipids. Stearic acid was mainly present in the form of PC and LPC. Palmitic acid was present in the most abundant molecular species in PI, PG and PA whereas linoleic acid formed the most abundant molecular species in PE.

17.
J Agric Food Chem ; 58(23): 12143-8, 2010 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-21062016

RESUMO

Policosanol (PC) is a mixture of high molecular weight aliphatic primary alcohols. Literature about the contents and compositions of PC derived from peanut varieties is scarce. Total PC composition and content in whole peanut grain samples from three varieties of peanut (two cultivars, AraC and AraT, and a wild one, AraA) were identified using a gas chromatograph system coupled with a mass spectrophotometer. The results show that, qualitatively, 21 components of peanut aliphatic alcohols were identified (C14-C30). Besides (C18=), the results exhibited a previously unreported mixture of PC compositions in the peanuts: the unsaturated PC (UPC), which are (C20=), (C21=), (C22=), and (C24=). The main components of total PC in Tunisian peanut kernels are docosanol (C22), (Z)-octadec-9-en-1-ol (C18=), hexadecanol (C16), and octadecanol (C18). Quantitatively, the total PC content of the whole peanut samples varied from 11.18 to 54.19 mg/100 g of oil and was higher than those of beeswax and whole sugar cane, which are sources of dietary supplements containing policosanol.


Assuntos
Arachis/química , Álcoois Graxos/química , Extratos Vegetais/química , Sementes/química , Arachis/classificação , Estrutura Molecular , Peso Molecular , Tunísia
18.
C R Biol ; 333(9): 642-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20816644

RESUMO

The analysis of the total lipid fraction from the Sayali variety of olive oil was accomplished in the present investigation. Glyceridic, unsaponifiable and flavour fractions of the oil were isolated and identified using several analytical methods. Chromatographic techniques have proven to be suitable for these determinations, especially capillary gas chromatography. Gas chromatography coupled to mass spectrometry was successfully used to identify sterols, triterpenes alcohols, 4-monomethylsterols, aliphatic alcohols and aroma compounds in our samples. Furthermore, solid phase microextraction was used to isolate volatiles from the total lipid fraction. Results from the quantitative characterization of Sayali olive oil showed that oleic acid (77.4%) and triolein (47.4%) were the dominant glyceridic components. However, the main compounds of the unsaponifiable fraction were beta-sitosterol (147.5mg/100g oil), 24-methylene cycloartenol (146.4mg/100g oil) and hexacosanol (49.3mg/100g oil). Moreover, results showed that the aldehydic compounds were the major flavours present in Sayali olive oil.


Assuntos
Lipídeos/análise , Óleos de Plantas/química , Álcoois/análise , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Delgada , Ácidos Graxos/análise , Álcoois Graxos/análise , Ionização de Chama , Cromatografia Gasosa-Espectrometria de Massas , Lipídeos/isolamento & purificação , Ácido Oleico/análise , Azeite de Oliva , Fitosteróis/análise , Sitosteroides/análise , Esteróis/análise , Triglicerídeos/análise , Trioleína/análise , Tunísia
19.
J Agric Food Chem ; 58(15): 8709-14, 2010 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-20681661

RESUMO

4-Desmethylsterols, the main component of the phytosterol fraction, have been analyzed during the development of Tunisian peanut kernels ( Arachis hypogaea L.), Trabelsia (AraT) and Chounfakhi (AraC), which are monocultivar species, and Arbi (AraA), which is a wild species, by gas chromatography-mass spectrometry. Immature wild peanut (AraA) showed the highest contents of beta-sitosterol (554.8 mg/100 g of oil), campesterol (228.6 mg/100 g of oil), and Delta(5)-avenasterol (39.0 mg/100 g of oil) followed by peanut cultivar AraC with beta-sitosterol, campesterol, and Delta(5)-avenasterol averages of 267.7, 92.1, and 28.6 mg/100 g of oil, respectively, and similarly for AraT 309.1, 108.4, and 27.4 mg/100 g of oil, respectively, were found. These results suggest that, in immature stages, phytosterol contents can be important regulator factors for the functional quality of peanut oil for the agro-industry chain from plant to nutraceuticals.


Assuntos
Arachis/química , Arachis/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas/métodos , Fitosteróis/análise , Extratos Vegetais/análise , Arachis/metabolismo , Fitosteróis/metabolismo , Extratos Vegetais/metabolismo , Sementes/química , Sementes/crescimento & desenvolvimento , Sementes/metabolismo
20.
J Sci Food Agric ; 90(10): 1745-9, 2010 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-20564436

RESUMO

BACKGROUND: Characterisation of the essential oils from O. glandulosum collected in three locations of Tunisia, chemical composition and the evaluation of their antioxidant activities were carried out. RESULTS: The essential oils from Origanum vulgare L. subsp. glandulosum (Desf.) Ietswaart collected from three localities of north Tunisia-Krib, Bargou and Nefza-were obtained in yields of 2.5, 3.0 and 4.6% (v/w), respectively. The essential oils were analysed by GC and GC/MS and assayed for their total phenolics content, by the Folin-Ciocalteu method, and antioxidant effectiveness, using the 2,2-diphenyl-1-picrylhydrazil (DPPH) radical scavenging assay. The main components of these essential oils, from Nefza, Bargou and Krib, were p-cymene (36%, 40% and 46%), thymol (32%, 39% and 18%), gamma-terpinene (24%, 12% and 16%) and carvacrol (2%, 2% and 15%), respectively). The ability to scavenge the DPPH radicals, expressed by IC(50), ranged from 59 to 80 mg L(-1). The total phenolic content, expressed in gallic acid equivalent (GAE) g kg(-1) dry weight, varied from 9.37 to 17.70 g kg(-1) dw. CONCLUSIONS: A correlation was identified between the total phenolic content of the essential oils and DPPH radical scavenger capacity. The occurrence of a p-cymene chemotype of O. glandulosum in the northern region of Tunisia is demonstrated.


Assuntos
Antioxidantes/farmacologia , Óleos Voláteis/farmacologia , Origanum/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Antioxidantes/análise , Compostos de Bifenilo , Óleos Voláteis/química , Fenóis/análise , Picratos , Extratos Vegetais/química , Tunísia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...