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1.
Antioxidants (Basel) ; 11(2)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35204079

RESUMO

Resveratrol is a powerful antioxidant molecule. In the human diet, its most important source is in Vitis vinifera grape peel and leaves. Resveratrol exists in two isoforms, cis- and trans. The diastereomeric forms of many drugs have been reported as affecting their activity. The aim of this study was to set up a cellular model to investigate how far resveratrol could counteract cytotoxicity in an oxidant agent. For this purpose, a keratinocyte cell line, which was genetically engineered with jelly fish green fluorescent protein, was treated with the free radical promoter Cumene hydroperoxide. The antioxidant activity of the trans-resveratrol and its diastereomeric mixture was evaluated indirectly in these treated fluorescent-engineered keratinocytes by analyzing the cell number and cell proliferation index. Our results demonstrate that cells, which were pre-incubated with resveratrol, reverted the oxidative damage progression induced by this free radical agent. In conclusion, fluorescent-engineered human keratinocytes represent a rapid and low-cost cellular model to determine cell numbers by studying emitted fluorescence. Comparative studies carried out with fluorescent keratinocytes indicate that trans-resveratrol is more efficient than diastereomeric mixtures in protecting cells from the oxidative stress.

2.
Biomed Pharmacother ; 142: 112052, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34426261

RESUMO

BACKGROUND: In breast cancer, low oxygen availability is associated with a more aggressive phenotype and with malignant evolution of non-invasive cells. Natural compounds have long attracted attention in cancer treatment, and in recent years garlic (Allium sativum) organosulfur derivatives have been shown to negatively affect growth and invasion of tumor cells. METHODS: Homemade ethanol-based garlic extract (GE) was administered to MCF7 and MCF10DCIS breast tumor cell lines grown under moderate hypoxia. Cell cycle, epithelial-to-mesenchymal transition and cancer stem cell markers were evaluated. RESULTS: We revealed that, in the non-invasive MCF10DCIS cells but not in the post-EMT MCF7 cells, low oxygen availability induced the decrease of E-cadherin and the increase of vimentin and motility, that were prevented by GE administration. In both cell lines, treatment with GE counteracted the up-modulation of CD133 positive cells induced by hypoxia. CONCLUSIONS: Overall, our data firstly revealed anti-cancer properties of garlic in non-invasive breast cancer cells. In particular, they demonstrated a protective role of this natural product against the hypoxia-induced increase of molecules that play crucial roles in tumor evolution, suggesting that garlic derivatives can be considered in new approaches for preventing progression of breast tumors from non-invasive to infiltrating lesions.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Hipóxia Celular/efeitos dos fármacos , Alho/química , Extratos Vegetais/farmacologia , Antígeno AC133/metabolismo , Antígenos CD/metabolismo , Caderinas/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Etanol/química , Humanos , Células-Tronco Neoplásicas/metabolismo , Vimentina/metabolismo
3.
Isotopes Environ Health Stud ; 56(3): 260-279, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32216466

RESUMO

Globalization of seafood product marketing caused the increase of request of an effective fish traceability that enhances the consumer confidence in food safety. In this study, an integrated multi analytical approach based on two different and independent analytical techniques (carbon and nitrogen stable isotopes and fatty acids analysis) was applied in order to identify different fish species and trace their geographical provenience. The investigation was focused on four species (Thunnus thynnus, Thunnus alalunga, Auxis rochei and Scomber scombrus) belonging to the Scombridae family. The DNA barcoding method confirmed genus and species for S. scombrus and A. rochei, but only genus for T. alalunga and T. thynnus. Carbon and nitrogen stable isotopes results evidenced different fish diets and trophic positions, whereas fatty acids analysis displayed that the unsaturated prevailed (∼60 %) over the saturated compounds with a variation among the species and the geographical area in particular for docosahexaenoic and eicosapentaenoic acids percentage. The principal component analysis applied to stable isotopes and fatty acids evidenced a good discrimination among species and their geographical catching area. This multi-disciplinary analytical approach could represent a promising tool to identify the commercial fish and trace their origin in order to guarantee the health of consumers.


Assuntos
Isótopos de Carbono/análise , Isótopos de Nitrogênio/análise , Perciformes/crescimento & desenvolvimento , Alimentos Marinhos/análise , Animais , Código de Barras de DNA Taxonômico , Ácidos Graxos/análise , Cadeia Alimentar , Geografia , Perciformes/classificação , Perciformes/genética , Análise de Componente Principal , Especificidade da Espécie
4.
J Pharm Biomed Anal ; 142: 28-34, 2017 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-28494336

RESUMO

Humulus lupulus L., commonly named hop, is well-known for its sedative and estrogenic activity. While hop cones are widely characterized, only few works have been carried out on the young shoots of this plant. In the light of this, the aim of this study was to identify for the first time the flavonoids present in young hop shoots and to compare the composition of samples harvested from different locations in Northern Italy with their antioxidant activity. The samples were extracted by means of dynamic maceration with methanol. The HPLC-UV/DAD, HPLC-ESI-MS and MS2 analysis were carried out by using an Ascentis C18 column (250×4.6mm I.D., 5µm), with a mobile phase composed of 0.1M formic acid in both water and acetonitrile, under gradient elution. Quercetin and kaempferol glycosides were the main compounds identified and quantified in hop shoot extracts. Total flavonols ranged from 2698±185 to 517±48µg/g (fresh weight). The antioxidant activity was determined by means of the radical scavenging activity assay against diphenylpicrylhydrazyl (DPPH) and by using a photochemiluscence assay with a Photochem® apparatus. The results showed that hop shoots represent a new source of flavonols; therefore, they can be useful for a possible incorporation in the diet as a functional food or applied in the nutraceutical ambit.


Assuntos
Humulus , Antioxidantes , Flavonoides , Flavonóis , Itália , Extratos Vegetais , Brotos de Planta
5.
Exp Clin Endocrinol Diabetes ; 125(7): 470-477, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28445896

RESUMO

Obesity and overweight are major contributors to the burden of chronic disease. Both are defined as abnormal or excessive fat accumulation and by increased production of free radicals leading to oxidative stress. The aim of the present study was to evaluate whether overweight and fat accumulation is associated with serum total antioxidant capacity (TAC) in men and women, irrespective of nutritional habits, nutrient intakes, physical activity, smoking, and other confounders, which may be responsible for modifying the association between serum TAC and overweight/obesity measures. This cross-sectional study was conducted on 60 normal weight and 60 overweight adults aged 25-49. All participants underwent standard anthromorphological measurements of body composition, blood pressure and biochemical measurements, aerobic capabilities assessment and dietary intake evaluation. TAC was measured by using the photochemioluminescence method. All data were analysed with SPSS software. Men had higher values of TAC than women and concentrations of TAC were significantly higher in overweight subjects compared to normal weight subjects. In the present study TAC tended to be increased by various metabolic risk factors, especially overweight/obesity parameters (body mass index, body fat), inflammation and increased serum levels of Cysteine, irrespective of nutritional habits, nutrient intakes, physical activity and smoking. Overweight and obesity at an early stage may stimulate TAC. Therefore, the elevation of TAC in overweight adults may be a compensatory response to oxidative stress, generated by reactive oxygen species.


Assuntos
Antioxidantes/metabolismo , Obesidade/sangue , Estresse Oxidativo , Adulto , Estudos Transversais , Feminino , Radicais Livres/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/patologia
6.
Food Chem Toxicol ; 105: 315-318, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28450129

RESUMO

Trans-resveratrol (trans-RSV) is a polyphenol with multiples biological properties, such as anti-inflammatory, antioxidant, anti-aging, anti-diabetic, and antiplatelet. It occurs naturally in grapes and derivate, peanuts and berries. Beauvericin (BEA) is a mycotoxin present in cereals that produces cytotoxicity, intracellular reactive oxygen species and lipid peroxidation. The general objective of this research was to evaluate whether trans-RSV could be used as a good polyphenol against damages produced by BEA. Because trans-RSV can be ingested through dietary supplements, to reach this goal, the following specific objectives were proposed: to determine a) the trans-RSV content in different polyphenol dietary supplements by capillary electrophoresis, b) the antioxidant capacity of the trans-RSV in polyphenol supplements, and c) the influence of BEA in the antioxidant capacity of trans-RSV when they are in combination by photochemioluminiscence assay. The results obtained in this study showed that all polyphenol dietary supplements present higher RSV content that the content of the label. The polyphenol supplements present antioxidant capacity. And the combination of trans-RSV and BEA did not affect the antioxidant capacity of trans-RSV. Thus, RSV could contribute to decrease oxidant effects produced by BEA.


Assuntos
Antioxidantes/química , Depsipeptídeos/química , Micotoxinas/química , Estilbenos/química , Depsipeptídeos/toxicidade , Suplementos Nutricionais/análise , Micotoxinas/toxicidade , Resveratrol
7.
Food Funct ; 7(10): 4222-4230, 2016 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-27713992

RESUMO

Nettle (Urtica dioica L.) is a well-known plant with a wide historical background use of stems, roots and leaves. Nettle leaves are an excellent source of phenolic compounds, principally 3-caffeoylquinic acid (3-CQA), caffeoylmalic acid (CMA) and rutin. The aim of this work was to evaluate the bioaccessibility (BAC), the bioavailability (BAV) and the antioxidant activity of nettle phenolic compounds present in foods and supplements. The BAC of nettle phenolics was evaluated with an in vitro dynamic digestion of real food matrices: the type of food matrix and chemical characteristic affected the kinetics of release and solubilization, with the highest BAC after duodenal digestion. A study of duodenal trans epithelial transport evidenced low bioavailability of native forms of 3-CQA, CMA and rutin. Simulation of colonic metabolism confirmed that phenolic compounds are fermented by gut microflora, confirming the need for further investigations on the impact of phenolic compounds at the large intestine level. Photochemiluminescence assay of the simulated digestion fluids demonstrated that ingestion of Urtica based foods contributes to create an antioxidant environment against superoxide anion radicals in the entire gastrointestinal tract (GIT).


Assuntos
Antioxidantes/farmacologia , Análise de Alimentos , Urtica dioica/química , Antioxidantes/química , Disponibilidade Biológica , Transporte Biológico , Células CACO-2 , Radicais Livres , Humanos , Superóxidos/química
8.
J Agric Food Chem ; 61(20): 4723-7, 2013 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-23627288

RESUMO

In recent years, there has been a great development in the search for new natural pesticides for crop protection aiming a partial or total replacement of currently used chemical nematicides. Glucosinolate breakdown products are volatile and are therefore good candidates for nematodes fumigants. In this article, the methanol-aqueous extract (1:1, w/v) of horseradish (Armoracia rusticana) fresh roots (MAH) was in vitro tested for nematicidal activity against second stage (J2) Meloidogyne incognita. The EC50 of MAH after 3 days of J2 immersion in test solutions was 251 ± 46 mg/L. The chemical composition analysis of the extract carried out by the GC-MS technique showed that allylisothicyanate was the most abundant compound. This pure compound induced J2 paralysis with an EC50 of 52.6 ± 45.6 and 6.6 ± 3.4 mg/L after 1 h and 3 days of incubation. The use of LC-MS/MS showed for the first time that horseradish root is rich in polyphenols. The study of isothiocyanate degradation in soil showed that allylisothiocyanate was the most quickly degradable compound (half-life <10 min), whereas no significant differences in half-life time were noted between degradation in regular and autoclaved soil.


Assuntos
Antinematódeos/farmacologia , Armoracia/química , Isotiocianatos/farmacologia , Raízes de Plantas/química , Tylenchoidea/efeitos dos fármacos , Animais , Cromatografia Gasosa-Espectrometria de Massas , Meia-Vida , Isotiocianatos/análise , Isotiocianatos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Solo/química
9.
J Food Sci ; 77(6): C646-52, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22583041

RESUMO

Two morphologically different cultivars of Italian melons (Baggio and Giusto) were characterized considering samples harvested in different times, at the beginning (BPP) and at the end of the physiological plant production period (EPP). Proximate composition, protein, minerals, pH, phenolic content, antioxidant capacity, ascorbic acid, carotenoids, condensed tannins, and flavonoids were measured, showing a significant decrease in EPP samples (phenolics, antioxidant capacity, condensed tannins, and flavonoids); ascorbic acid decreased in Giusto cv, carotenoids in Baggio cv. Mineral content increased in either the cultivars (EPP samples). Year-to-year difference was significantly highlighted; the plant growing cycle significantly affected the chemotype. Despite these effects, the Principal Component Analysis (PCA) permitted the discrimination of Baggio from Giusto cv, and the discrimination of BPP from EPP samples as well.


Assuntos
Antioxidantes/análise , Cucumis melo/química , Cucumis melo/crescimento & desenvolvimento , Proteínas Alimentares/análise , Inspeção de Alimentos , Frutas/química , Frutas/crescimento & desenvolvimento , Minerais/análise , Proteínas de Plantas/análise , Ácido Ascórbico/análise , Carotenoides/análise , Flavonoides/análise , Concentração de Íons de Hidrogênio , Itália , Valor Nutritivo , Fenóis , Análise de Componente Principal , Proantocianidinas/análise , Estações do Ano , Especificidade da Espécie , Espectrofotometria Atômica
10.
J Environ Sci Health B ; 46(6): 480-5, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21726145

RESUMO

The house fly, Musca domestica L., a relevant sanitary pest, is mainly controlled by insecticides. However, an inappropriate use of chemicals may induce resistance, treatment efficacy decline and environmental damages. We evaluated toxicity of some organophosphates, pyrethroids, spinosad and neonicotinoids by topical applications on adults of a M. domestica strain (OcRo) collected from an intensive chicken farm in Northern Italy, in comparison to a susceptible strain (s-DBF). The OcRo strain exhibited higher levels of resistance (RR50) to four pesticides in comparison to s-DBF. Spinosad and imidacloprid had very low RR50, thus were still efficient in OcRo control. We also tested resistance to pesticides in OcRo after topical applications of synergistic compounds. Hydrolases were involved in phosphorganic detoxification and cytochrome P450 monoxygenases in that of pyrethroids. These results indicate that OcRo strain is now multiresistant to organophosphates and pyrethroids, and this should be considered for an environmentally safe pest management.


Assuntos
Moscas Domésticas/efeitos dos fármacos , Controle de Insetos/métodos , Inseticidas/farmacologia , Animais , Galinhas , Sistema Enzimático do Citocromo P-450/metabolismo , Combinação de Medicamentos , Imidazóis/farmacologia , Resistência a Inseticidas/efeitos dos fármacos , Itália , Macrolídeos/farmacologia , Neonicotinoides , Nitrocompostos/farmacologia , Organofosfatos/farmacologia , Piretrinas/farmacologia
11.
J Environ Sci Health B ; 46(6): 486-90, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21726146

RESUMO

To avoid environmental pollution and health problems caused by the use of traditional synthetic pesticides, there is a trend to search for naturally occurring toxicants from plants. Among the compounds discussed for anti-fungal and insecticidal activity, the natural extracts from garlic and horseradish have attracted considerable attention. The objective of this study is to determine the insecticidal and anti-fungal activity of Armoracia rusticana and Allium sativum L. extracts against larvae of Aedes albopictus (Skuse) and some pathogenic fungi. For the insecticidal test, horseradish and garlic extracts were prepared from fresh plants (cultivated in Emilia Romagna region) in a solution of ethanol 80 % and the two different solutions were used at different concentrations (for the determination of the lethal dose) against the fourth instar mosquito's larvae. The fungicidal test was carried out by the agar plates technique using garlic and horseradish extracts in a 10 % ethanol solution against the following organisms: Sclerotium rolfsii Sacc., Trichoderma longibrachiatum, Botrytis cinerea Pers., Fusarium oxysporum Schlecht. and Fusarium culmorum (Wm. G. Sm.) Sacc. The first results demonstrated that the horseradish ethanol extracts present only a fungistatic activity against Sclerotium rolfsii Sacc., Fusarium oxysporum Schlecht. and F. culmorum (Wm.G. Sm) Sacc. while garlic extracts at the same concentration provided a good fungicidal activity above all against Botrytis cinerea Pers. and S. rolfsii. A. rusticana and A. sativum preparations showed also an interesting and significant insecticidal activity against larvae of A. albopictus, even if horseradish presented a higher efficacy (LC50 value of 2.34 g/L), approximately two times higher than garlic one (LC50 value of 4.48 g/L).


Assuntos
Aedes/efeitos dos fármacos , Armoracia/química , Fungos/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Alho/química , Inseticidas/farmacologia , Extratos Vegetais/farmacologia , Animais , Culicidae/efeitos dos fármacos , Fungos/patogenicidade , Larva/efeitos dos fármacos
12.
Nutrients ; 2(3): 280-9, 2010 03.
Artigo em Inglês | MEDLINE | ID: mdl-22254020

RESUMO

1H NMR spectra were recorded of methanolic extracts of seven soybean varieties (Glycine max.), cultivated using traditional and organic farming techniques. It was possible to identify signals belonging to the groups of amino acids, carbohydrates, organic acids and aromatic substances in the spectra. In the aromatic zone, the isoflavone signals were of particular interest: genistein, daidzein, genistin, daidzin, malonylgenistin, acetylgenistin, malonyldaidzin signals were assigned and these compounds were quantified, resulting in accordance with published data, and further demonstrating the potential of the NMR technique in food science.


Assuntos
Glycine max/química , Isoflavonas/análise , Extratos Vegetais/química , Aminoácidos/análise , Carboidratos/análise , Humanos , Espectroscopia de Ressonância Magnética/métodos , Compostos Orgânicos/análise
13.
J Environ Sci Health B ; 42(7): 795-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17763036

RESUMO

Among the compounds discussed for anti-microbial and anti-fungal use allicin (allylthiosulfinate, diallyl disulfide-S-monoxide), an active ingredient of garlic, has attracted considerable attention. The objective of this study is to determine the antifungal activity of a local garlic ecotype (Voghiera) extracts against different pathogens. Primary screening was carried out by the agar plates technique using ethanol garlic extract at four final concentrations against the following organisms: Alternaria alternata, Aspergillus spp., Colletotrichum acutatum, Didymella bryoniae, Fusarium culmorum, Fusarium avenaceum, Fusarium gramineareum, Gliocladium roseum 47, Pythium splendens, Rhizoctonia solani, Sclerotium rolfsii, Stemphylium vesicarium, Trichoderma longibranchiatum, and Botrytis cinerea. Secondary screening was carried out using a lyophilized and a spray-dried preparation at different concentrations against the organisms selected for the high inhibition garlic effect in the primary screening and compared with the commercial fungicides mancozeb and iprodione. The best results were observed for the spray-dried garlic compound that showed a good fungicidal activity at the concentration of 1.5 g/10 mL while lyophilized garlic at the same concentration exhibited less inhibition activity against the four fungi analyzed in the second screening.


Assuntos
Fungos/efeitos dos fármacos , Fungicidas Industriais/farmacologia , Alho/química , Extratos Vegetais/farmacologia , Contagem de Colônia Microbiana , Dissulfetos , Relação Dose-Resposta a Droga , Liofilização , Fungos/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Ácidos Sulfínicos/farmacologia
14.
J Sep Sci ; 30(4): 491-501, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17444218

RESUMO

Flavonoid content and composition in 124 accessions of forage and grain legumes was assessed by means of HPLC-DAD and HPLC-ESI-MS analyses of seed extracts. Excluding soybean, only 7 out of 77 grain legume accessions exhibited a total flavonoid content higher than 0.1 mg/g fresh seed weight (mean content 0.33 +/- 0.31 mg/ g fresh seed weight); while in 38 out of 47 forage legume, the mean flavonoid content was 1.49 +/- 0.89 mg/g fresh seed weight. On the basis of their higher seed flavonoid content and agronomic relevance, two grain and five forage legume accessions were selected for further HPLC-ESI-MS analyses aimed to identify bioactive compounds. Chemical analysis of the selected accessions permitted the identification of several flavonoids with pharmaceutical properties such as vitexin in Vigna angularis and Trigonella foenum-graecum, quercetin in all Trifolium spp and Medicago sativa, taxifolin in Trifolium pratense and Trifolium alexandrinum, myricetin in Trifolium repens, kaempferol in Phaseolus vulgaris and T. repens and luteolin in M. sativa and T. alexandrinum. Since much of literature information is regarding flavonoid content and composition of the green part of legume species, the obtained results contributed to fill the gap in knowledge about flavonoid content at the seed level.


Assuntos
Grão Comestível/química , Fabaceae/química , Flavonoides/análise , Flavonoides/química , Sementes/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Estrutura Molecular
15.
J Agric Food Chem ; 54(26): 9985-91, 2006 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-17177531

RESUMO

This paper describes a method for achieving qualitative identification of four rice varieties from two different Italian regions. To estimate the presence of genetic diversity among the four rice varieties, we used polymerase chain reaction-randomly amplified polymorphic DNA (PCR-RAPD) markers, and to elucidate whether a relationship exists between the ground and the specific characteristics of the product, we studied proximate composition, fatty acid composition, mineral content, and total antioxidant capacity. Using principal component analysis on genomic and compositional data, we were able to classify rice samples according to their variety and their district of production. This work also examined the discrimination ability of different parameters. It was found that genomic data give the best discrimination based on varieties, indicating that RAPD assays could be useful in discriminating among closely related species, while compositional analyses do not depend on the genetic characters only but are related to the production area.


Assuntos
Oryza/química , Oryza/genética , Antioxidantes/análise , Ácidos Graxos/análise , Itália , Minerais/análise , Oryza/crescimento & desenvolvimento , Técnica de Amplificação ao Acaso de DNA Polimórfico , Sementes/química
16.
J Agric Food Chem ; 53(3): 678-83, 2005 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-15686419

RESUMO

Chemotype analyses and random amplified polymorphic DNA (RAPD) genomic analyses have been applied to the characterization of Allium sativum variety from Voghiera (Ferrara, Italy), a typical Italian product actually demanding the Protected Designation of Origin (PDO). The garlic from Voghiera is characterized by peculiar morphological and composition characteristics. The proximate composition and atomic absorbance spectrometry elemental pattern of this garlic suggested as the chemical composition did not depend on the intrinsic pedologic soil features only, but it was probably connected to some peculiar genetic characters. Amplification of genomic DNA using random primers highlighted a good clustering differentiating of Voghiera Allium sativum from five commercial reference samples used in this study (Piacentino, Serena, France, China, and Adriano varieties), confirming the existence of intervarietal genetic difference. The intravarietal polymorphisms of Voghiera samples were low.


Assuntos
Alho/química , Alho/genética , DNA de Plantas/análise , Alho/classificação , Itália , Minerais/análise , Técnica de Amplificação ao Acaso de DNA Polimórfico
17.
J Agric Food Chem ; 52(13): 4080-9, 2004 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-15212451

RESUMO

Wheat quality criteria continually evolve in response to market pressure and consumer preference. Characterization of cereal cultivars for quality and agronomic properties, have widely shown the importance of the protein content to ensure good quality products. The aim of this work is a comparison of reversed-phase high performance liquid chromatography (RP-HPLC) and free zone capillary electrophoresis (FZCE) in the identification of Italian wheat cultivars and detection of durum wheat flour adulteration. Mainly alcohol soluble (gliadins) and water soluble (albumins) proteins were extracted from 14 common wheat cultivars and from 9 durum wheat cultivars. In RP-HPLC chromatograms, wheat albumins and gliadins eluted between 3 and 9 min and between 10 and 42 min, respectively. Even if the chosen chromatographic conditions (reversed phase) did not permit a complete resolution of hydrophilic proteins such as albumins, a good reproducibility was observed for both albumins and gliadins. In FZCE electropherograms, wheat albumins and gliadins migrated between 8 and 14 min and 16-25 min, respectively. A good reproducibility was found for wheat albumins, while the relatively poor reproducibility of gliadin fractions was a consequence of the selected separation conditions aimed to separate in the same run either hydrophilic (albumins) and alcohol-soluble (gliadins) proteins. The principal component analysis (PCA) of HPLC and FZCE data evidenced that both techniques allowed the univocal identification of the great proportion of investigated wheat cultivars. Three peaks were exclusively detected in RP-HPLC chromatograms of common wheat cultivars, while three unique peaks were found in FZCE electropherograms of common wheat cultivars. These peaks were investigated as a basis for detecting and estimating the adulteration of durum wheat flour with flour from common wheat. The direct relationship between the area of the peaks and adulteration level enabled standard curves to be constructed. The standard curves showed that adulteration may be quantified by either RP-HPLC or FZCE.


Assuntos
Cromatografia Líquida de Alta Pressão , Eletroforese Capilar , Contaminação de Alimentos/análise , Proteínas de Plantas/análise , Triticum/química , Albuminas/análise , Farinha/análise , Gliadina/análise , Reprodutibilidade dos Testes , Triticum/classificação
18.
Int J Food Microbiol ; 86(1-2): 163-8, 2003 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-12892931

RESUMO

The isomers of 2,3-butanediol [R,R; S,S; R,S (meso-form)] and of acetoin (R,S) were determined in laboratory wine fermentations carried out by 50 yeast strains, 10 for each of the following species, Saccharomyces cerevisiae, Kloeckera apiculata, Candida stellata, Metschnikowia pulcherrima and Brettanomyces bruxellensis, in order to evaluate if such parameters might be used to differentiate wines obtained with different yeast species. According to analysis of variance (ANOVA), the strains of the same species behaved similarly, whereas the five yeast species behaved differently so that species-specific profiles were recognized. Moreover, the discriminant analysis grouped the wines into five groups, each including the 10 wines obtained by the 10 yeast strains of the same species. Trials were also included where musts partially fermented by non-Saccharomyces species were inoculated with a selected strain of S. cerevisiae to complete fermentation, and the content in 2,3-butanediol and acetoin isomers was again determined and statistical analysis was performed. Although the final values of these parameters resembled those obtained in pure fermentation with S. cerevisiae, statistical analysis discriminated wines according to the yeast species performing the first fermentation phase.


Assuntos
Acetoína/metabolismo , Butileno Glicóis/metabolismo , Vinho/microbiologia , Leveduras/metabolismo , Acetoína/química , Análise de Variância , Butileno Glicóis/química , Fermentação , Microbiologia Industrial , Isomerismo , Saccharomyces cerevisiae/metabolismo , Especificidade da Espécie
19.
J Agric Food Chem ; 50(25): 7407-11, 2002 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-12452667

RESUMO

Because of the health implications of resveratrol and piceid, which are widely present in foods, we focused our attention on the development of a highly efficient methodology for their characterization and measurement. On the basis of our experience in capillary electrophoresis for separation of polyphenolic compounds, we developed a general analytical method for piceid identification which was also applicable to complex natural mixtures such as red wine. In view of its very limited availability from natural sources, we first directed our attention to the development of a synthetic route suitable to produce an adequate amount of polydatin (piceid or resveratrol 3-O-beta-D-glucopyranoside). The latter was synthesized by a new one-step procedure which afforded the expected product in a good yield. The studied compounds were also investigated for their stability to UV irradiation.


Assuntos
Eletroforese Capilar , Glucosídeos/análise , Glucosídeos/síntese química , Estilbenos/análise , Estilbenos/síntese química , Estabilidade de Medicamentos , Resveratrol , Vinho/análise
20.
J Agric Food Chem ; 50(6): 1461-4, 2002 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-11879021

RESUMO

Cv. Star Ruby grapefruit (Citrus paradisi Macf.) were subjected to a 3-min dip in water at room temperature (20 degrees C) or at 50 degrees C with or without 25, 50, or 100 mg/L azoxystrobin (AZX). Then, the fruits were subjected to cold quarantine at 2 degrees C and 90-95% relative humidity (RH) for 3 weeks and then stored for 5 weeks at 8 degrees C and approximately 85% RH and for another 2 weeks at 20 degrees C and 80% RH to simulate a 2-week marketing period (SMP). No AZX residues were detected in the albedo and pulp following treatments at 20 or 50 degrees C, the total amount of residues being recovered from the flavedo tissue. There was a relationship between the AZX uptake in fruit and the amount of fungicide employed at 20 or 50 degrees C. When AZX was applied to the fruit at 25 mg/L at 20 degrees C, the residue level averaged 0.11 mg/kg (active ingredient, whole fruit basis). This residue concentration increased by 50 and 75% when the application rate increased from 25 to 50 or 100 mg/L, respectively. A similar pattern of accumulation was detected in fruit subjected to treatments at 50 degrees C. However, treatments at 50 degrees C produced residue levels higher than the treatments at 20 degrees C, with increases ranging from 63 to 84%, for the same concentration. Storage conditions did not affect the amount of AZX residues in the fruit. Treatment at 50 or 100 mg/L at 20 degrees C reduced the incidence of moderate to severe chilling injury (CI). Water dips at 50 degrees C reduced the incidence and severity of CI to a very low extent, with no additional advantages when hot water was used in combination with AZX. Treatments with 50 or 100 mg/L of AZX at 20 degrees C produced beneficial effects in decay control similar to those of 25 mg/L AZX at 50 degrees C or hot water alone. Better results were achieved with 50 or 100 AZX at 50 degrees C, providing complete control of decay during cold storage and with negligible decay after SMP. It was concluded that when AZX was applied at 50 degrees C, low doses of fungicide and minimal residue levels in fruit were required to control the postharvest decay of grapefruit. This treatment does not impair fruit quality and offers very interesting prospects for large scale application, due to the reduced potential toxicity of AZX to nontarget organisms and to the environment.


Assuntos
Acrilatos/administração & dosagem , Citrus , Conservação de Alimentos , Fungicidas Industriais/administração & dosagem , Pirimidinas/administração & dosagem , Acrilatos/análise , Citrus/química , Resíduos de Drogas/análise , Fungicidas Industriais/análise , Metacrilatos , Pirimidinas/análise , Estrobilurinas
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