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1.
Nat Prod Res ; 36(18): 4799-4803, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34875942

RESUMO

Fridericia chica (Bonpl.) L.G. Lohmann (synonym Arrabidaea chica Verlot) is widely used in Brazilian folk medicine. Considering overcoming pitfalls of scaling up production of plant extracts, herein the effects of N2 atmosphere for extract spray-drying process is reported. Samples were monitored by in vitro antioxidant activity and microbiological evaluation. The drying atmosphere influenced 3-deoxyanthocyanines content when using air as atomizing gas, decreasing carajurin (37.5%) content with concomitant increase in luteolin yield (24.1%). Both drying processes preserved the pharmacological activity. In the cell migration test with HaCaT cells, the extract dried under air flow (5 µg/mL) promoted wound closure by 78% (12 hours) whereas the extract dried using N2 flow promoted 49% (12 hours), with 98% closure (12 hours) for the positive control. The antimicrobial evaluation for Staphylococcus aureus did not differ within drying atmospheres, with MIC (minimum inhibitory concentration) at 0.39 mg/mL. Therefore, the drying process reported herein did not interfere with the biological activity's outcome.


Assuntos
Bignoniaceae , Antioxidantes/farmacologia , Atmosfera , Extratos Vegetais/farmacologia , Cicatrização
2.
Food Chem Toxicol ; 48(10): 2972-9, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20678538

RESUMO

The suitability of different commercial olive oil categories for domestic frying was investigated. Oil samples were taken every 3h of frying and evaluated for free acidity, peroxide and p-anisidine values, specific extinction coefficients, oxidative stability, fatty acids, vitamin E, ß-carotene and total phenols, until the total polar compounds achieved the maximum legal value (25%). All olive oils were fried during more time than the commercial vegetable oil blend taken for comparison (from 24 to 27 h, against 15 h). The extra-virgin Protected Designation of Origin (PDO) olive oil was characterized by reduced levels of oxidation and hydrolysis, and superior amounts of minor antioxidant compounds. The "olive oil" commercial category behaves similarly, but "Cobrançosa" olive oils performance was slightly worse, and clearly different between years, highlighting the importance of blending different cultivars. The vegetable oil, despite containing significantly higher amounts of vitamin E, was highly susceptible to oxidation under frying conditions when compared to all olive oils. The results also show that the chemical composition of olive oils, particularly the amount of natural antioxidants, are important parameters in their predictive behavior along the frying process, but mostly that olive oil is clearly resistant to frying conditions, independently to the commercial category chosen.


Assuntos
Óleos de Plantas/análise , Antioxidantes/análise , Culinária , Ácidos Graxos não Esterificados/análise , Temperatura Alta , Indicadores e Reagentes , Peróxidos Lipídicos/análise , Azeite de Oliva , Oxirredução , Fenóis/análise , Espectrofotometria Ultravioleta , Temperatura , Tocoferóis/análise , Tocotrienóis/análise , beta Caroteno/análise
3.
J Agric Food Chem ; 55(5): 1832-8, 2007 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-17291006

RESUMO

Espresso coffee (EC) brews were analyzed for beta-carboline [norharman (NH) and harman (H)] contents, by RP-HPLC with fluorescence detection. The influence of the coffee species (arabica or robusta), the roast degree, and the brew length was studied. The results show that the content of NH and H in EC is dependent primarily on the coffee species, followed by brew length. The roast degree has only a minor influence on the final content of NH and H in EC. When compared with other coffee brews, EC has an amount of these beta-carbolines (in micrograms per liter) similar to that of mocha coffee, both being more concentrated than filter and press-pot coffees. Therefore, the consumer's preferences will determine the amount of NH and H ingested daily. For the caffeinated 30 mL of EC, the arabica coffees contain about 4.08 microg of NH and 1.54 microg of H. Commercial blends (usually with a maximum of 30% robusta) range from the cited arabica values to 10.37 microg of NH and 4.35 microg of H.


Assuntos
Café/química , Harmina/análogos & derivados , Carbolinas , Coffea/química , Manipulação de Alimentos/métodos , Harmina/análise , Temperatura Alta , Mutagênicos/análise , Neurotoxinas/análise , Pressão , Sementes/química , Especificidade da Espécie , Fatores de Tempo
4.
J Agric Food Chem ; 54(4): 1329-36, 2006 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-16478256

RESUMO

Hazelnuts from 19 cultivars collected during 3 consecutive-year crops, in 2 different geographical localities, for a total of 79 samples, were evaluated for their contents in tocopherols and tocotrienols by normal-phase high-performance liquid chromatography coupled to a series arrangement of a diode array and a fluorescence detector. Seven compounds were identified and quantified. All samples presented alpha-, beta-, gamma-, and delta- tocopherols and beta-tocotrienol; alpha- and gamma-tocotrienols were detected in some of the studied samples. alpha-Tocopherol was the major compound in all samples, ranging from 105.9 to 226.8 mg/kg of hazelnut. Considering the generality of the obtained results, an identical qualitative and quantitative pattern was found, which can define a chemical fingerprint that may be helpful in the assessment of identity and quality of hazelnut oils. Statistical analyses were carried out in order to check for differences among cultivars, year crops, and geographical localities. Although some differences were observed when different-year crops and geographical localities were considered, neither of these factors seemed to produce considerable differences in terms of tocopherol and tocotrienol contents. Some minor differences were observed among cultivars.


Assuntos
Corylus/química , Sementes/química , Tocoferóis/análise , Tocotrienóis/análise , Análise de Variância , Cromatografia Líquida de Alta Pressão , Meio Ambiente , Portugal , Especificidade da Espécie
5.
J Agric Food Chem ; 54(4): 1315-21, 2006 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-16478254

RESUMO

The effect of roasting on some nutritional characteristics of hazelnut lipidic fraction was investigated. Hazelnuts (Corylus avellana L.) were submitted to several different thermal treatments, comprising different temperatures (125-200 degrees C) and times of exposure (5, 15, and 30 min) and analyzed for their moisture and crude fat. Raw and roasted hazelnuts were also analyzed for their compositions in phytosterols and fatty acids (including trans isomers) by GC-FID, triacylglycerols by HPLC-ELSD, and tocopherols and tocotrienols by HPLC-DAD/fluorescence spectroscopy. Minor changes occurred in the fatty acid and triacylglycerol compositions. As temperatures and roasting periods increased, generally, a modest increase of oleic and saturated fatty acids and a decrease of linoleic acid, expressed as relative percentages, occurred. Similarly, an increase of triacylglycerols containing oleic acid moieties and a decrease of those containing linoleic acid moieties were found in the roasted samples. Roasting caused a modest decrease of the beneficial phytosterols (maximum 14.4%) and vitamin E homologues (maximum 10.0%) and a negligible increase of the trans fatty acids.


Assuntos
Corylus/química , Temperatura Alta , Lipídeos/análise , Sementes/química , Ácidos Graxos/análise , Fitosteróis/análise , Tocoferóis/análise , Ácidos Graxos trans/análise , Triglicerídeos/análise
6.
J Agric Food Chem ; 54(2): 449-56, 2006 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-16417303

RESUMO

The oil of several hazelnut (Corylus avellana L.) samples was extracted and evaluated for their triacylglycerol (TAG) composition. Trials were conducted in two Portuguese localities (Vila Real and Felgueiras) during three consecutive years and involved a total of 19 cultivars. The samples were analyzed by reversed-phase high-performance liquid chromatography with evaporative light-scattering detection. Sample preparation was fast and simple, consisting only of the dissolution of the oil in acetone, homogenization, and filtration, allowing this technique to be suitable for routine analyses. All samples presented a similar qualitative profile composed of eleven compounds: LLL, OLL, PLL, OOL, POL, PPL, OOO, POO, PPO, SOO and PSO (P, palmitoyl; S, stearoyl; O, oleoyl; and L, linoleoyl). The main components were OOO, LOO, and POO, reflecting the high content of oleic acid in hazelnut oils. A total of 79 different samples were studied, and the obtained data were statistically analyzed. Significant differences were verified in canonical variate plots when cultivars were grouped by country of origin. In general, the American cultivars were richer in TAGs with saturated fatty acids moieties, and the group of French, German, and English cultivars was richer in TAGs containing linoleic acid moieties. Differences were also significant when cultivars were grouped by year of production, showing that besides genetic factors, the TAG composition can be influenced by environmental factors.


Assuntos
Corylus/química , Corylus/genética , Meio Ambiente , Sementes/química , Triglicerídeos/análise , Cromatografia Líquida de Alta Pressão , Ácido Linoleico/análise , Ácido Oleico/análise , Portugal , Especificidade da Espécie
7.
Anal Sci ; 21(12): 1545-8, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16379404

RESUMO

A normal-phase high-performance liquid chromatography (NP-HPLC) method for the determination of tocopherols and tocotrienols in hazelnuts is reported. Three extraction procedures (with and without saponification) were assayed; the best results were obtained with a simple solid-liquid extraction procedure. Chromatographic separation was achieved using an Inertsil 5 SI column using isocratic elution with hexane/1,4-dioxane (95.5:4.5, v/v) at a flow rate of 0.7 mL/min. The effluent was monitored by a series arrangement of a diode-array followed by a fluorescence detector. All compounds were separated in a short period of time (17 min). The method proved to be rapid, sensitive, reproducible and accurate, allowing the simultaneous determination of all vitamin E homologues.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Corylus/química , Tocoferóis/análise , Tocotrienóis/análise , Sensibilidade e Especificidade
8.
J Agric Food Chem ; 53(13): 5467-72, 2005 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-15969535

RESUMO

The tocopherol and tocotrienol composition of walnuts (Juglans regia L.) was determined for nine cultivars (cvs. Arco, Franquette, Hartley, Lara, Marbot, Mayette, Mellanaise, Parisienne, and Rego). Walnuts were harvested over three consecutive years from two different geographical origins (Bragança and Coimbra, Portugal), for a total of 26 samples. The methodology employed was a normal-phase high-performance liquid chromatography coupled to a series arrangement of a diode array detector followed by a fluorescence detector, allowing the simultaneous analysis of all tocopherols and tocotrienols. The analyses showed that all samples presented a similar qualitative profile composed of five compounds: alpha-tocopherol, beta-tocopherol, gamma-tocopherol, delta-tocopherol, and gamma-tocotrienol. gamma-Tocopherol was the major compound in all samples, ranging from 172.6 to 262.0 mg/kg, followed by alpha- and delta-tocopherols, ranging from 8.7 to 16.6 mg/kg and from 8.2 to 16.9 mg/kg, respectively. Multivariate analysis of the data obtained showed the existence of significant differences in composition among cultivars. These differences were also significant when cultivars were grouped by year of production, showing that besides genetic factors, the vitamin E composition was influenced by environmental factors.


Assuntos
Juglans/química , Sementes/química , Vitamina E/análise , Cromatografia Líquida de Alta Pressão , Especificidade da Espécie , Tocoferóis/análise , Tocotrienóis/análise
9.
J Agric Food Chem ; 52(26): 7964-9, 2004 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-15612783

RESUMO

A total of 26 walnut (Juglans regia L.) samples from 9 cultivars (Arco, Franquette, Hartley, Lara, Marbot, Mayette, Mellanaise, Parisienne, and Rego) harvested in the 2001, 2002, and 2003 crop years and grown in two geographical origins (Braganca and Coimbra, Portugal) were evaluated with regard to their triacylglycerol composition. The methodology employed was reversed-phase high-performance liquid chromatography coupled to an evaporative light-scattering detector (RP-HPLC-ELSD) after extraction of the lipidic fraction of the nuts. Nine compounds were separated, identified, and quantified. All samples presented an identical qualitative profile composed by LLnLn, LLLn, LLL, OLLn, OLL, PLL, OOL, and PLO (P = palmitoyl; O = oleoyl; L = linoleoyl; Ln = linonenoyl). Trilinolein (LLL) was the major triglyceride, followed by dilinoeoyl-oleoyl-glycerol (OLL) and dilinoleoyl-linolenoyl-glycerol (LLLn), with mean values of 37.7, 18.5, and 18.4%, respectively. Significant differences in composition were found between cultivars, and these differences were also significant when cultivars were grouped by year of production, showing that besides genetic factors, the triacylglycerol composition can be strongly influenced by environmental factors.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Juglans/química , Triglicerídeos/análise , Óleos de Plantas/química
10.
J Agric Food Chem ; 52(16): 4943-7, 2004 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-15291455

RESUMO

A duplex Polymerase Chain Reaction (PCR) method able to detect bovine milk in ovine cheeses was developed. This method is based on the mitochondrial 12S and 16S rRNA genes to generate fragments of different lengths. The proposed methodology presents an alternative DNA extraction procedure faster and more economical than the kits commercially available. A linear normalized calibration curve was obtained between the log of the ratio of the bovine band intensity and the sum of bovine and ovine band intensities versus the log of cow's milk percentage. The method was applied successfully to the detection and quantification of raw, pasteurized, and powdered bovine milk in different cheeses. The proposed duplex PCR provides a simple, sensitive, and accurate approach to detect as low as 0.1% bovine milk in cheeses and to quantify bovine milk in ovine cheeses in the range of 1-50%.


Assuntos
Bovinos/genética , Queijo/análise , DNA/análise , Leite/química , Reação em Cadeia da Polimerase/métodos , Ovinos , Animais , Queijo/classificação , RNA Ribossômico/genética , RNA Ribossômico 16S/genética
11.
J Agric Food Chem ; 51(26): 7698-702, 2003 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-14664531

RESUMO

Six cultivars (Franquette, Marbot, Mayette, Mellanaise, Lara, and Parisienne) of walnuts (Juglans regia L.) were collected during the 2001 crop, from Bragança, Portugal. Chemical composition, including moisture, total oil content, crude protein, ash, carbohydrates, and nutritional value, was evaluated. Fat was the predominant component, ranging from 62.3 to 66.5%. Total oil was extracted and analyzed for fatty acids, sterols, oxidative stability, and peroxide value. Fatty acids and sterols were determined by gas-liquid chromatography coupled to a flame ionization detector. Eighteen fatty acids were quantified. Polyunsaturated fatty acids and, in particular, linoleic acid were predominant. Beta-Sitosterol, delta(5)-avenasterol, and campesterol were the major sterols found. Differences were observed among the studied cultivars, especially in peroxide values and in the sterol profile.


Assuntos
Ácidos Graxos/análise , Juglans/química , Valor Nutritivo , Nozes/química , Fitosteróis/análise , Carboidratos/análise , Cromatografia Gasosa , Oxirredução , Óleos de Plantas/análise , Proteínas de Plantas/análise , Portugal
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