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1.
J Sci Food Agric ; 101(2): 638-647, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32691876

RESUMO

BACKGROUND: An antioxidant formula based on peanut skins and hulls was developed and characterized for total and single polyphenols, as well as antioxidant power, considering the contribution provided by each peanut by-product. Subsequently, it was evaluated for its effect on the sensory properties and aroma stability of peanut bars over a 100-day period. To this purpose, snacks fortified, or not, with the natural additive were experimentally produced. RESULTS: Peanut hulls contributed to a greater extent than skins with respect to boosting the content of bioactives and the antioxidnt activity of the antioxidant formula, which was marked by a phenol content of (approximately 807 mg gallic acid equivalents g-1 ) and a 2,2-diphenyl-1-picrylhydrazyl activity similar to that of butylated hydroxytoluene (85.96% and 89.30%, respectively). From a sensory perspective, the incorporation of the formulation in snacks caused only a slightly stronger perception of astringent and bitter notes. Pyrazines, phenol, furan and pyrrole derivatives defined the aroma of snacks, being more abundant in fortified than in conventional samples. Such volatiles faded over storage, with different trends in the examined products. For example, the sum of 2,5-dimethylpyrazine, 2-ethylpyrazine and 2,3-dimethylpyrazine was 9.49 and 8.87 ppm at day 15; 5.57 and 7.16 ppm at day 45; and 5.03 and 4.65 ppm at day 100, respectively, in fortified and conventional snacks. Hydroxymethylfurfural decreased constantly over storage in conventional samples and only after day 45 in fortified bars. CONCLUSION: Overall, the antioxidant formulation did not compromise the sensory desirability of peanut snacks and induced a preservative effect on their aroma, especially during the first 15 days of storage. © 2020 Society of Chemical Industry.


Assuntos
Arachis/química , Alimentos Fortificados/análise , Odorantes/análise , Resíduos/análise , Arachis/metabolismo , Armazenamento de Alimentos , Humanos , Fenóis/química , Fenóis/metabolismo , Sementes/química , Sementes/metabolismo , Lanches , Paladar
2.
J Sci Food Agric ; 100(7): 2971-2981, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32048295

RESUMO

BACKGROUND: The term 'grape (Vitis vinifera) water' refers to a by-product from the cryoconcentration of must that, if not reclaimed, would be considered as wastewater. In this study, the nutraceutical potential of waters reclaimed from the cryoconcentration of Grillo and Moscato musts was evaluated. RESULTS: Both waters showed physicochemical parameters in agreement with Italian regulation for drinking water, and interesting levels of F- (3.02-8.02 mg L-1 ) and SO4 - (52.85-49.34 mg L-1 ). Inorganic elements, including Mg (5.54-7.78 mg L-1 ), K (47.12-59.87 mg L-1 ), Fe (219.09-205.32 µg L-1 ), and Zn (189.65-127.30 µg L-1 ), and phenolic contents <35 mg GAE L-1 contributed to determine moderate antioxidant activities. Considering fatty acid composition, oleic and linoleic acids predominated, being higher in Moscato than Grillo samples (64.42% versus 58.22%, and 5.42% versus 6.07%). Grape waters displayed also rich aroma profiles, including mainly esters, alcohols and terpenoids. The latter components (i.e. linalool and α-terpineol) were more abundant in Moscato than in Grillo (13% versus 8%). Interestingly, some minor volatiles, characterized the vine of provenance (e.g. benzaldehyde and 3-methylbutylacetate in Moscato). All grape waters showed also a considerable fraction of ethyl lactate, six-carbon compounds and acetates, reflecting the proximity of samples to the grapes of origin. CONCLUSION: In a growing scenario of environmental decay and resource depletion, results from this study support an innovative and profitable waste recycling strategy for the wine industry. © 2020 Society of Chemical Industry.


Assuntos
Resíduos Industriais/análise , Vitis/química , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Suplementos Nutricionais , Manipulação de Alimentos/métodos , Reciclagem , Vinho
3.
Mar Drugs ; 17(3)2019 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-30884901

RESUMO

The phylum Cnidaria is one of the most important contributors in providing abundance of bio- and chemodiversity. In this study, a comprehensive chemical investigation on the nutritional and nutraceutical properties of Mediterranean jellyfish Pelagia noctiluca was carried out. Also, compositional differences between male and female organisms, as well as between their main anatomical parts, namely bell and oral arms, were explored in an attempt to select the best potential sources of nutrients and/or nutraceuticals from jellyfish. With the exception of higher energy densities and total phenolic contents observed in females than males, no statistically significant differences related to the specimen's sex were highlighted for the other compound classes. Rather, the distribution of the investigated chemical classes varied depending on the jellyfish's body parts. In fact, crude proteins were more abundant in oral arms than bells; saturated fatty acids were more concentrated in bells than oral arms, whereas polyunsaturated fatty acids were distributed in the exact opposite way. On the other hand, major elements and trace elements demonstrated an opposite behavior, being the latter most accumulated in oral arms than bells. Additionally, important nutraceuticals, such as eicosapentaenoic and docosahexaenoic acids, and antioxidant minerals, were determined. Overall, obtained data suggest the potential employment of the Mediterranean P. noctiluca for the development of natural aquafeed and food supplements.


Assuntos
Suplementos Nutricionais/análise , Valor Nutritivo , Cifozoários/química , Animais , Ácidos Graxos Insaturados/análise , Feminino , Masculino , Fenóis/análise , Proteínas/análise , Oligoelementos/análise
4.
Mar Drugs ; 16(12)2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30544601

RESUMO

Enormous marine biodiversity offers an endless reservoir of chemicals for many applications. In this scenario, the extraction of seaweeds represents an interesting source of compounds displaying antimicrobial activity. In particular, among the different red algae, Gracilaria gracilis plays an important role due to the presence of important bioactives in its composition. In spite of these features, an efficient culture system is still absent. In the present study, a novel algal culture method was developed and compared to another more common cultural practice, widely reported in literature. A higher efficiency of the new method, both for daily growth rate and biomass, was assessed. Furthermore, the growth inhibitory activity of five extracts, obtained using ethanol, methanol, acetone, chloroform or diethyl ether as a solvent, from the cultured G. gracilis was tested against Gram-positive and Gram-negative pathogens. Algal extracts exhibited a considerable inhibitory activity against B. subtilis strains, while a slight inhibition was observed against V. fischeri. The different extracts showed significant differences in bacterial growth inhibition, with the highest activity that was recorded for the ethanol extract, followed by that of methanol. Based on the chemical characterization, these findings could be related to the antimicrobial activity played by the combination of total carbohydrates and polyphenols, which were determined at high levels in ethanol and methanol extracts, as well as by the highest number and levels of single polyphenols. Conversely, the lower growth inhibitory activities found in chloroform and diethyl ether extracts could be related to the isolation of minor lipid classes (e.g., neutral and medium polar lipids) composed by fatty acids, such as stearic, oleic and arachidonic acids, typically characterized by antimicrobial activity. In consideration of the results obtained, the present study has a double implication, involving both the field of cultural practices and the exploitation of natural sources for the isolation of antimicrobial agents useful both in pharmaceutical and food applications.


Assuntos
Antibacterianos/farmacologia , Produtos Biológicos/farmacologia , Técnicas de Cultura/métodos , Gracilaria/metabolismo , Extratos Vegetais/farmacologia , Aliivibrio fischeri/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Bacillus subtilis/efeitos dos fármacos , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Biomassa , Gracilaria/química , Testes de Sensibilidade Microbiana , Extratos Vegetais/isolamento & purificação , Alga Marinha/química , Alga Marinha/metabolismo , Solventes
5.
Molecules ; 23(7)2018 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-30022015

RESUMO

Roseroot (Rhodiola rosea L.) belongs to plants revealing adaptogenic properties, which are attributed to the presence of specific phenolic compounds and are reflected mainly as antioxidant activity. The aim of the present study was to determine the antioxidant and antibacterial activity of various products obtained from R. rosea (underground organs as well as their aqueous and ethanolic dry extracts) in relation to the chemical profiles of phenolic and essential oil compounds. The chemical profiles were determined by High-performance Liquid Chromatography with a diode-array detector (HPLC-DAD) and Gas chromatography-mass spectrometry (GC-MS), antioxidant activity by (1,1-Diphenyl-2-picrylhydrazyl) Scavenging Capacity Assay (DPPH), (2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)) Scavenging Capacity Assay (ABTS) and Ferric Reducing Antioxidant Power Assay (FRAP) and antimicrobial properties were expressed as minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) values following the broth microdilutions method. The results show that the investigated samples differed in terms of their chemical compositions and biological activities. The extracts were more abundant in phenolic compounds (salidroside, tyrosol, and rosavin derivatives) in comparison to dried underground organs. The content of the determined phenolics in the analyzed extracts was affected by the solvent used for extraction. The ethanolic extract was characterized by the highest content of these substances in comparison to the aqueous one and the dried raw material, especially with regard to rosavin (969.71 mg/100 g). In parallel, this extract showed the strongest antioxidant and antibacterial activity. However, dried R. rosea underground organs also revealed strong antibacterial effects against, for example, Staphylococcus strains.


Assuntos
Antibacterianos , Antioxidantes , Extratos Vegetais/química , Rhodiola/química , Staphylococcus/crescimento & desenvolvimento , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia
6.
Anal Bioanal Chem ; 407(17): 5211-25, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25963648

RESUMO

Fish oil made from menhaden (Brevoortia tyrannus) can be used as a dietary supplement for the presence of high levels of the long-chained omega-3 fatty acids, viz. epentaenoic and docosahexanoic. In this work, for the first time, two different multidimensional approaches were developed and compared, in terms of peak capacity, for triacylglycerol characterization. In particular, silver ion chromatography with a silver-ion column and non-aqueous reverse-phase liquid chromatography with a C18 column were tested in both comprehensive (stop-flow) and off-line modes. The use of mass spectra attained by atmospheric pressure chemical ionization for both LC approaches, and the fatty acids methyl esters profile of menhaden oil obtained by gas chromatography analysis, greatly supported the elucidation of the triacylglycerol content in menhaden oil. The off-line approach afforded a better separation and, thus, higher peak capacity to allow identifying and semiquantifying more than 250 triacylglycerols. Such a huge number has never been reported for a menhaden oil sample.The main disadvantage of such an approach over the stop-flow one was the longer analysis time, mainly attributable to solvent exchange between the two dimensions.


Assuntos
Óleos de Peixe/química , Triglicerídeos/análise , Animais , Cromatografia Gasosa/métodos , Cromatografia Líquida/métodos , Cromatografia de Fase Reversa/métodos , Peixes , Espectrometria de Massas/métodos
7.
J Sep Sci ; 37(7): 792-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24478239

RESUMO

Reversed-phase-HPLC analysis by means of superficially porous silica particle columns (fused-core) was applied to the investigation of flavonoids, coumarins, and psoralens in lime juice samples. Hesperidin (367.0 ± 16.0 ppm) and eriocitrin (148.0 ± 7.9 ppm) were the most abundant flavonoids. Fifteen coumarins and furocoumarins were determined, including bergamottin (29.6 ± 1.1 ppm), 5-geranyloxy-7-methoxycoumarin (16.5 ± 0.6 ppm), and oxypeucedanin hydrate (9.9 ± 0.5 ppm) as predominant compounds. These molecules are today well known for their beneficial effects on human health. As a consequence, the present study, beyond investigating for the first time the chemical composition of lime juice, highlights also its health-promoting qualities, due to its content of flavonoids and coumarins.


Assuntos
Bebidas , Compostos de Cálcio/química , Compostos Heterocíclicos/análise , Óxidos/química , Oxigênio/análise , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Cumarínicos/análise , Flavonoides/análise , Furocumarinas/análise , Porosidade , Dióxido de Silício/química , Propriedades de Superfície
8.
Phytochem Anal ; 25(5): 468-75, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24692205

RESUMO

INTRODUCTION: Ruta chalepensis L. (Rutaceae) is widespread in the Mediterranean area. This plant has a solid tradition in ethnomedicine because of its various biological activities. Based on previous reports, the main volatile constituents of R. chalepensis are 2-undecanone and 2-nonanone, but most are still unknown, particularly fatty acid composition. OBJECTIVE: To exhaustively characterise the chemical composition of the aerial parts from R. chalepensis plants collected from the wild in Sicily, within a project aiming at the evaluation and characterisation of medicinal plants from the Mediterranean flora. The study was directed toward the determination of volatiles and fatty acids in samples of R. chalepensis obtained from different aerial plant parts and from plants harvested at different times. METHODS: GC with flame ionisation detection, GC-MS and two-dimensional gas chromatography (GC × GC) advanced techniques, with support of dedicated mass spectral databases provided with retention index (RI) information, were applied to determine both volatiles and fatty acids. Samples were extracted by hydrodistillation and underwent methylic transesterification in order to be transformed into the correspondent fatty acid methyl esters (FAMEs). RESULTS: The monodimensional analysis by GC-MS with RI confirmed that 2-nonanone and 2-undecanone are the predominant components in all the plant parts, followed by esters and monoterpenes. A different distribution was observed of the main compounds in the various plant parts depending on the life cycle of the plant (vegetative or reproductive stage). The multidimensional GC × GC analysis allowed for a complete screening of the fatty acids. About 65% of the total were polyunsaturated fatty acids (PUFA), followed by 30% of saturated fatty acids (SFA). CONCLUSION: A detailed GC volatile fingerprint of R. chalepensis flowers, leaves, fruits and stems was established, highlighting the compositional differences depending on plant organs and life cycle. The results indicated R. chalepensis as a good source of fatty acids from the w3 and w6 series. In both essential oil and lipidic extract, many compounds were determined for the first time.


Assuntos
Cromatografia Gasosa/métodos , Ácidos Graxos/química , Cromatografia Gasosa-Espectrometria de Massas , Componentes Aéreos da Planta/química , Ruta/química , Óleos Voláteis/química , Óleos de Plantas/química
9.
Nat Prod Res ; 37(16): 2742-2747, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36134545

RESUMO

Chemical composition and in vitro antimicrobial activity of parsley [Petroselinum crispum (Mill.) Fuss] and ginger (Zingiber officinale Roscoe) essential oils from store-bought parsley plants and ginger rhizomes were evaluated. A sensory analysis was performed on aged cheese slices treated with a mix of each essential oil and seed oil. Parsley essential oil was selected as the best compromise between sensory influence and antimicrobial activity and tested to evaluate its antifungal effects on cheese slices experimentally contaminated with Aspergillus flavus. Monoterpenes and α-zingiberene were the most abundant compounds in parsley and ginger essential oil, respectively. Both essential oils showed in vitro antimicrobial activity against different fungal species while only a bacterial strain (Enterococcus faecalis) was sensible to ginger essential oil. Only the cheese slices treated with parsley essential oil were appreciated by the panellists and its use has been effective in preventing the A. flavus growth in cheese.

10.
Foods ; 12(13)2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37444367

RESUMO

Skin cancer is a prevalent type of cancer worldwide and has a high growth rate compared to other diseases. Although modern targeted therapies have improved the management of cutaneous neoplasms, there is an urgent requirement for a safer, more affordable, and effective chemoprevention and treatment strategy for skin cancer. Nutraceuticals, which are natural substances derived from food, have emerged as a potential alternative or adjunctive treatment option. In this review, we explore the current evidence on the use of omega-3 fatty acids and polyphenols (curcumin, epigallocatechin gallate, apigenin, resveratrol, and genistein) for the treatment of melanoma and non-melanoma skin cancer (NMSC), as well as in their prevention. We discuss the mechanisms of action of the aforementioned nutraceuticals and their probable therapeutic benefits in skin cancer. Omega-3 fatty acids, curcumin, epigallocatechin gallate, apigenin, resveratrol, and genistein have several properties, among which are anti-inflammatory and anti-tumor, which can help to prevent and treat skin cancer. However, their effectiveness is limited due to poor bioavailability. Nanoparticles and other delivery systems can improve their absorption and targeting. More research is needed to evaluate their safety and effectiveness as a natural approach to skin cancer prevention and treatment. These compounds should not replace conventional cancer treatments, but may be used as complementary therapy under the guidance of a healthcare professional.

11.
Foods ; 11(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35626956

RESUMO

Lignans, a group of polyphenols, have been identified in eight cold pressed oils from fruits, nuts, and seeds, retrieved from the Brazilian market. The oils under investigation were avocado, Brazilian nut, canola, coconut, grapeseed, macadamia, palm, and pequi. Olive oil was selected as a reference oil, since numerous data on its lignan content are available in literature. The qualitative and quantitative profiles were obtained, after extraction, by means of UFLC-ESI-MS/MS analyses. The total lignan content showed a high variability, ranging from 0.69 mg·Kg-1 (pequi) to 7.12 mg·Kg-1 (grapeseed), with the highest content registered for olive oil. Seven lignans were quantified, matairesinol and pinoresinol being the most abundant. The LC-MS/MS method was validated, showing linearity in the range of 12.5-212.5 mg·Kg-1, LOD in the range of 0.18-11.37 mg·Kg-1, and LOQ in the range of 0.53-34.45 mg·Kg-1. Additionally, part of the study was focused on the evaluation of the flavor profile, this being a key element in consumers' evaluations, by means of HS-SPME-GC. In total, 150 volatile compounds were determined in the eight oils, with identified fractions ranging from 91.85% (avocado) to 96.31% (canola), with an average value of 94.1%. Groups of components contributed characteristically to the flavour of each oil.

12.
Nutrients ; 14(8)2022 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-35458228

RESUMO

The effect of dietary enrichment with flaxseed, selenium and vitamin E, and market class on the nutritional and functional value of breast meat was evaluated. A completely randomized block design was set up, where the experimental unit (n = 6000 birds) received conventional or enriched diet and was slaughtered at 37 (light class), 47 (medium class), or 57 (heavy class) days of life. Hence, functional and standard Pectoralis major muscles from every market class were analyzed for FA composition, inorganic elements and vitamin E. Lipid metabolism indices and health lipid indicators were assessed along with the nutritional value. A multiple linear model revealed that in breasts, the dietary treatment significantly influenced (p < 0.05) the FA profile, lipid metabolism and health lipid indices, while the slaughtering weight was related (p < 0.05) to most of elements (e.g., Na, Mg, K, Mn, and Se) and vitamin E. The interdependence of the two factors had strong relations (p < 0.05) with total PUFAs, including linolenic acid, desaturase activities, health lipid indices, trace essential elements and vitamin E. Consequently, enriched meat from heavy chickens showed the best functional and nutritional traits. Overall, the study pointed out that both market class and dietary manipulation are two relevant factors to consider for producing breast meat with higher nutritional and functional value.


Assuntos
Linho , Selênio , Ração Animal/análise , Animais , Galinhas/metabolismo , Dieta/veterinária , Suplementos Nutricionais , Linho/metabolismo , Lipídeos , Carne/análise , Selênio/metabolismo , Vitamina E/metabolismo , Vitamina E/farmacologia
13.
Pharmaceuticals (Basel) ; 15(6)2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35745654

RESUMO

Helichrysum italicum (Roth) G. Don. is one of the most important cosmetic and medicinal plants originating from the Mediterranean region of Europe. The aim of this study was to assess the chemical profile as well as antioxidant and antibacterial potential of the species cultivated in the temperate climate of Central Europe. The analyses were carried out using herbs and inflorescences. The content of essential oil ranged from 0.25 g × 100 g-1 in the herb to 0.31 g × 100 g-1 in the inflorescences. Neryl acetate, accompanied by α-pinene in the herb (10.42%), and nerol in inflorescences (15.73%) were the dominants here. Rutoside, as well as rosmarinic, chlorogenic, neochlorogenic, isochlorogenic b and cichoric acids, were detected in both raw materials using HPLC-DAD. Within this group, cichoric acid was the dominant (2647.90 mg × 100 g-1 in the herb, 1381.06 mg × 100 g-1 in the inflorescences). The herb appeared to be more abundant in phenolics in comparison with the inflorescences. When given antioxidant activity (determined using DPPH and ABTS assays), both methanolic extract and essential oil obtained from the herb indicated higher potential than those originating from the inflorescences (74.72, 61.38 and 63.81, 58.59% in the case of DPPH, respectively). In turn, regarding antimicrobial activity, the essential oil from inflorescences was distinguished by stronger bacteriostatic power than the herb essential oil. Gram-positive bacteria were more sensitive to both essential oils in comparison with Gram-negative ones, with S. aureus ATCC 25923 as the most susceptible (MIC 1; MBC 16 mg × mL-1) among tested strains.

14.
Food Chem ; 386: 132746, 2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-35334318

RESUMO

To prevent PGI (Protected Geographical Indication) cherry tomato of Pachino (Sicily, Italy) from frauds, an alternative method, which includes chemometric treatments, was proposed. The content of 32 inorganic elements (macro-micronutrients and lanthanides) present in 16 PGI and 24 not PGI cherry tomato samples cv Naomy, and in 16 PGI and 8 not PGI soil samples, was determined by Inductively Coupled Plasma - Mass Spectrometer (ICP-MS). To identify the elements able to differentiate PGI and not PGI cherry tomato samples, Principal Components Analysis (PCA) and Canonical discriminant analysis (CDA) were performed. The first two principal components (PC1-PC2) explain a total variance of 71,41% between PGI and not PGI group, whereas CDA showed Zn, Cd, Mn and Ca as inorganic markers able to correctly classify the 100% of samples. Furthermore, with a translocation factor (K), evaluated in soil/plant chain, the comparison of absorption trends for PGI and not PGI samples was realized.


Assuntos
Solanum lycopersicum , Quimiometria , Análise Discriminante , Sicília , Solo
15.
Traffic ; 9(4): 559-73, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18208507

RESUMO

Phosphatidylinositol-(4,5)-bisphosphate [PtdIns(4,5)P2] is a key regulator of endocytosis. PtdIns(4,5)P2 generation at the plasma membrane in yeast is mediated by the kinase Mss4p, but the mechanism underlying the temporal and spatial activation of Mss4p to increase formation of PtdIns(4,5)P2 at appropriate sites is not known. Here, we show that ADP ribosylation factor (Arf)3p, the yeast homologue of mammalian Arf6, is necessary for wild-type levels of PtdIns(4,5)P2 at the plasma membrane. Arf3p localizes to dynamic spots at the membrane, and the behaviour of these is consistent with it functioning in concert with endocytic machinery. Localization of Arf3p is disrupted by deletion of genes encoding an ArfGAP homology protein Gts1p and a guanine nucleotide exchange factor Yel1p. Significantly, deletion of arf3 causes a reduction in PtdIns(4,5)P2 at the plasma membrane, while increased levels of active Arf3p, caused by deletion of the GTPase-activating protein Gts1, increase PtdIns(4,5)P2 levels. Furthermore, elevated Arf3p correlates with an increase in the number of endocytic sites. Our data provide evidence for a mechanism in yeast to positively regulate plasma membrane production of PtdIns(4,5)P2 levels and that these changes impact on endocytosis.


Assuntos
Fatores de Ribosilação do ADP/metabolismo , Membrana Celular , Endocitose/fisiologia , Fosfatidilinositol 4,5-Difosfato/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Ribosilação do ADP/genética , Animais , Membrana Celular/química , Membrana Celular/metabolismo , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Fosfotransferases/genética , Fosfotransferases/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool) , Estrutura Terciária de Proteína , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Técnicas do Sistema de Duplo-Híbrido
16.
J Sep Sci ; 32(1): 99-108, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19051190

RESUMO

In this paper, we report the qualitative and quantitative composition of the volatile and the oxygenated heterocyclic fraction of citron (Citrus medica L. cv. Diamante (Diamante citron)). The fruits selected for the extraction were of three types: green citron of little size, green citron of big size, and yellow citron after 1 month from the harvest. The essential oils were extracted using three different methods. The nine samples of oil thus obtained were analyzed by high resolution GC (HRGC)-flame ionization detection (FID), HRGC-MS, and RP-HPLC. They differ only in the quantitative composition, while the qualitative profile was the same. The volatile fraction of every sample of oil is characterized by a high content of limonene, gamma-terpinene, and monoterpene aldehydes and a lower content of alpha- and beta-pinene and myrcene, sesquiterpenes, and aliphatic aldehydes. Enantioselective (Es)-GC analysis of the extracts allowed the determination of the enantiomeric distribution of five terpenoid compounds; a prevalence of four dextrorotatory isomers was observed. Oxypeucedanin was the main component of the oxygenated heterocyclic fraction in the extracts of green fruits, while citropten was the major oxygenated compound in the oil obtained from yellow citron.


Assuntos
Citrus/química , Óleos Voláteis/análise , Óleos Voláteis/isolamento & purificação , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Reprodutibilidade dos Testes , Fatores de Tempo
17.
J Chromatogr A ; 1603: 262-268, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31257037

RESUMO

A novel application of SPME-GC and UHPLC is presented for the elucidation of an unexplored citrus by-product, namely lemon wax. In view of the current environmental protection strategies, directed toward reuse and/or recovery of waste products, this study aimed to evaluate a possible utilization of a discarded fraction from citrus fruits processing. Headspace SPME coupled with GC-MS and GC-FID allowed determining a residual amount (162.25 mg kg-1) of lemon volatiles, by means of accurate calibration of 38 terpenoids through linear regression analysis (R2 = 0.99). SPME method development, was supported by statistical analysis, consisting of experimental design and multisample comparison, where parameters such as type of coating, temperature and time of fiber exposure, were manipulated towards optimization. The optimized method was validated, showing limits of quantification (LOQ) and of detection (LOD) in the ranges 0.24 - 2.65 ng g-1 and 0.11 - 0.87 ng g-1, respectively; recoveries ranged from 84.9% to 111.5%. After optimization and validation, the UHPLC-PDA method revealed the presence in lemon wax samples of six coumarins, the most abundant being bergamottin (964 mg kg-1), followed, in decreasing amount, by citropten, 8-geranyloxypsoralen, biacangelicin, oxypeucedanin, 5-geranyloxy-7-methoxycoumarin; each analyte was calibrated by external standard methodology. Sensitivity (LOD, 31 - 112 ng g-1; LOQ, 102-370 ng⋅ g-1), accuracy (recovery, 81-94%), and precision (Retention time RSD, 0.03 - 0.09%; peak area RSD, 1.03-2.92%), were also measured.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Citrus/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos Industriais/análise , Microextração em Fase Sólida/métodos , Resíduos/análise , Ceras/análise , Calibragem , Análise Multivariada , Reprodutibilidade dos Testes , Compostos Orgânicos Voláteis/análise
18.
J Sep Sci ; 31(19): 3347-51, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18792013

RESUMO

The present research is focused on the use of comprehensive 2-D GC (GC x GC) for the elucidation of the human plasma fatty acid (FA) profile. The enhanced sensitivity, increased separation power and the formation of group-type patterns provided by GC x GC enabled the identification and quantification of a high number of both well known and unexpected FAs, for a total of 65 components. Peak assignment was, in most cases, supported by using pure standard compounds. The results attained demonstrated the usefulness of the multidimensional GC method in this fundamental field of research.


Assuntos
Cromatografia Gasosa/métodos , Ácidos Graxos/análise , Plasma/química , Humanos
19.
J Sep Sci ; 31(19): 3329-36, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18792014

RESUMO

The present research is focused on the offline combination of normal-phase LC to double-oven GC x GC-quadrupole MS. Initially, a diesel sample was subjected to automated LC x GC in order to define the elution windows of four fractions, viz., saturated hydrocarbons, monocyclic aromatics, dicyclic aromatics, tri- + tetracyclic aromatics; each fraction was collected exploiting the LC system in a further analysis and subjected to large-volume-injection-GC x GC analysis using an apolar-polar column combination. The GC x GC operational conditions were tuned in relation to the specific separation requirements of each heart-cut. The main benefits of what can be defined as offline LC-GC x GC were: (i) the high first-dimension LC selectivity; (ii) the injection of high sample amounts in the GC x GC system, enabling the detection and quantification of a series of low-amount diesel constituents; (iii) improved GC x GC operational conditions for each heart-cut with respect to direct GC x GC.


Assuntos
Cromatografia Gasosa/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Cromatografia Gasosa/instrumentação , Cromatografia Líquida/instrumentação , Gasolina/análise , Espectrometria de Massas/instrumentação
20.
Food Chem ; 240: 222-230, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28946265

RESUMO

The purpose of the present work was to find a correlation between microencapsulation technology applied to wines and the resulting quality of the wine itself in terms of volatile composition and phenolic profile. To this aim, samples of Nero d'Avola wines produced in Sicily (Italy) were investigated in order to: i) elucidate the aromatic composition by means of HS-SPME coupled with GC-MS; ii) assess the polyphenolic content by UHPLC mass spectrometry; iii) compare the results obtained from both the screenings with those relative to the same wines that had previously been subjected to spray-drying. The results showed a marked reductionThe results here obtained evidenced a marked reduction of odour active compounds in microencapsulated wines, after resolubilization in water/ethanol; when considering the total amount of volatiles, a twofold reduction was observed. Conversely, the qualitative analysis of phenolic compounds and anthocyanin-derived pigments showed no influence of the spray-drying process on these functional constituents.


Assuntos
Vinho , Antocianinas , Cromatografia Gasosa-Espectrometria de Massas , Sicília , Vitis
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