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1.
Molecules ; 26(1)2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33375633

RESUMO

An evaluation of antioxidant and anticancer activity was screened in Leptocarpha rivularis DC flower extracts using four solvents (n-hexane (Hex), dichloromethane (DCM), ethyl acetate (AcOEt), and ethanol (EtOH)). Extracts were compared for total extract flavonoids and phenol contents, antioxidant activity (2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), ferric reducing antioxidant potential (FRAP), total reactive antioxidant properties (TRAP) and oxygen radical absorbance capacity (ORAC)) across a determined value of reduced/oxidized glutathione (GSH/GSSG), and cell viability (the sulforhodamine B (SRB) assay). The most active extracts were analyzed by chromatographic analysis (GC/MS) and tested for apoptotic pathways. Extracts from Hex, DCM and AcOEt reduced cell viability, caused changes in cell morphology, affected mitochondrial membrane permeability, and induced caspase activation in tumor cell lines HT-29, PC-3, and MCF-7. These effects were generally less pronounced in the HEK-293 cell line (nontumor cells), indicating clear selectivity towards tumor cell lines. We attribute likely extract activity to the presence of sesquiterpene lactones, in combination with other components like steroids and flavonoids.


Assuntos
Antineoplásicos Fitogênicos/química , Asteraceae/química , Neoplasias/tratamento farmacológico , Extratos Vegetais/química , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Flavonoides/química , Flores/química , Células HEK293 , Humanos , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia
2.
Molecules ; 23(6)2018 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-29875340

RESUMO

To investigate the anti-Saprolegnia activities of chalconic compounds, nine dialkoxychalcones 2⁻10, along with their key building block 2',4'-dihydroxychalcone 1, were evaluated for their potential oomycide activities against Saprolegnia australis strains. The synthesis afforded a series of O-alkylated derivatives with typical chalcone skeletons. Compounds 4⁻10 were reported for the first time. Interestingly, analogue 8 with the new scaffold demonstrated remarkable in vitro growth-inhibitory activities against Saprolegnia strains, displaying greater anti-oomycete potency than the standard drugs used in the assay, namely fluconazole and bronopol. In contrast, a dramatic loss of activity was observed for O-alkylated derivatives 2, 3, 6, and 7. These findings have highlighted the therapeutic potential of the natural compound 1 scaffold to be exploitable as a drug lead with specific activity against various Saprolegnia strains.


Assuntos
Antifúngicos/farmacologia , Chalconas/farmacologia , Peixes/microbiologia , Saprolegnia/efeitos dos fármacos , Animais , Antifúngicos/química , Chalconas/química , Fluconazol/farmacologia , Ligação de Hidrogênio , Testes de Sensibilidade Microbiana , Propilenoglicóis/farmacologia , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes , Análise Espectral/métodos , Relação Estrutura-Atividade
3.
J Sci Food Agric ; 94(9): 1729-38, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24243589

RESUMO

BACKGROUND: Flaxseed is an important source of lignan secoisolariciresinol diglucoside (SDG) and its aglycone, secoisolariciresinol (SECO). These phenolic compounds can be metabolized to the mammalian lignans enterodiol (ED) and enterolactone (EL) by human intestinal microflora. Flaxseed lignans are known for their potential health benefits, which are attributed to their antioxidant and phytoestrogenic properties. The focus of this study was to determine the bioaccessibility of plant and mammalian lignans in whole flaxseed (WF) and flaxseed flour (FF) throughout the entire digestive process. Moreover, the metabolic activity of intestinal microflora was evaluated. RESULTS: A single-batch in vitro simulation of the digestive process was performed, including fermentation by the intestinal microflora in the colon. Bioaccessibility was calculated as (free lignan)/(total lignan). In digested WF, the bioaccessibility values of SECO, ED and EL were 0.75%, 1.56% and 1.23%, respectively. Conversely, in digested FF, the bioaccessibility values of SDG, ED and EL were 2.06%, 2.72% and 1.04%, respectively. The anaerobic count and short-chain fatty acids indicate that bacteria survival and carbohydrate fermentation occurred. CONCLUSION: The contents of both SDG and ED were significantly higher in digested FF than in digested WF. FF facilitated the action of intestinal bacteria to release SDG and metabolize ED.


Assuntos
4-Butirolactona/análogos & derivados , Butileno Glicóis/metabolismo , Colo/metabolismo , Linho/química , Glucosídeos/metabolismo , Lignanas/metabolismo , Sementes/química , 4-Butirolactona/metabolismo , Bactérias Anaeróbias/crescimento & desenvolvimento , Bactérias Anaeróbias/metabolismo , Disponibilidade Biológica , Colo/microbiologia , Ácidos Graxos Voláteis/metabolismo , Fermentação , Humanos , Técnicas In Vitro
4.
Foods ; 13(17)2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39272463

RESUMO

Proficiency testing (PT) allows food laboratories to endorse their competency to provide food safety guarantees to producers and consumers. One of the recommended methods for assigning reference values in PT with a small number of participants consists in considering the results that a laboratory obtains by means of a calibration test based on certified reference material (CRM). The present study delves into the results from eight PT rounds on the determination of fat and crude protein from raw milk, with modifications in the number of samples and the analysis sessions from that required by the ISO 13528:2022. The uncertainty criterion of the assigned value established by the ISO 13528:2022 standard was met by 93% of the participating laboratories, which allowed most participants to be evaluated through z-score. The assigned values were generally compatible with the results obtained by the participants. Thus, it can be concluded that the design for the assignment of the reference value is appropriate for PT with a limited number of participants. It is recommended for future PT to limit the uncertainty of the CRM according to their availability and to update the standard deviation of the proficiency assessment for the Mid-Infrared Spectroscopy method (MIR).

5.
Food Chem Toxicol ; 109(Pt 2): 1125-1134, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28322969

RESUMO

This study was designed to estimate the dietary intake of total arsenic, inorganic arsenic, cadmium, mercury, sodium, and potassium by the general adult population (aged 18-65) of Valdivia, Chile. Calculations were based on a 24-h dietary recall survey. The highest dietary intake of t-As (73.0 µg/day), i-As (20.0 µg/day), Cd (18.0 µg/day), Hg (5.8 µg/day), Na+ (3112.8 mg/day), and K+ (2077.5 mg/day) were for 70-kg adults. Estimating carcinogenic risk (CR > 4 × 10-4) due to exposure to i-As indicated that consumers remain at low risk for cancer. The cumulative health risk was evaluated by summing the target hazard quotient of cadmium (0.26) mercury (0.27) and inorganic arsenic (0.96); this calculation allows us to express the total target hazard quotient as 1.50 where a value > 1 indicates that there is a potential health risk for the population. Total intake of Cd and Hg were therefore within the limits estimated as being safe whereas Na+ and K+ intake for the Valdivia population did not follow the recommended values established by the World Health Organization (WHO). The Na+ intake exceeded the daily recommended intake while K+ intake was lower than the daily recommended intake. This indicates a health risk for the Valdivia population.


Assuntos
Arsênio/análise , Cádmio/análise , Contaminação de Alimentos/análise , Mercúrio/análise , Potássio/análise , Sódio/análise , Adolescente , Adulto , Idoso , Arsênio/metabolismo , Cádmio/metabolismo , Chile , Dieta , Feminino , Humanos , Masculino , Mercúrio/metabolismo , Pessoa de Meia-Idade , Vigilância da População , Potássio/metabolismo , Sódio/metabolismo , Inquéritos e Questionários , Adulto Jovem
6.
PLoS One ; 12(7): e0180993, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28686742

RESUMO

The effect of four cooking methods was evaluated for proximate composition, fatty acid, calcium, iron, and zinc content in salmon and Chilean jack mackerel. The moisture content of steamed salmon decreased (64.94%) compared to the control (68.05%); a significant decrease was observed in Chilean jack mackerel in all the treatments when compared to the control (75.37%). Protein content in both salmon and Chilean jack mackerel significantly increased under the different treatments while the most significant decrease in lipids was found in oven cooking and canning for salmon and microwaving for Chilean jack mackerel. Ash concentration in both salmon and Chilean jack mackerel did not reveal any significant differences. Iron and calcium content only had significant changes in steaming while zinc did not undergo any significant changes in the different treatments. Finally, no drastic changes were observed in the fatty acid profile in both salmon and Chilean jack mackerel.


Assuntos
Culinária/métodos , Perciformes/metabolismo , Salmo salar/metabolismo , Alimentos Marinhos/análise , Animais , Cálcio/análise , Chile , Ácidos Graxos/análise , Proteínas de Peixes/análise , Humanos , Ferro/análise , Micro-Ondas , Zinco/análise
7.
Food Chem ; 196: 848-52, 2016 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-26593564

RESUMO

Oregano and thyme possess beneficial properties for human health, mainly attributable to monoterpenes such as thymol and carvacrol. The main objective of this research was to assess, on starchy food, the impact of cooking (boiling and baking) and delivery (ground leaves and essential oil) modes on retention and bioaccessibility of thymol and carvacrol. Retention was assessed after cooking, while bioaccessibility was estimated in cooked samples using an in vitro digestion model. Our results indicate that bioaccessibility was weakly dependent on cooking and delivery modes (27-33%). Boil cooking presented 20% more retention than baking for both compounds. When essential oil was added to the food matrix, thymol was retained almost 25% more when compared with ground leaves' addition. Conversely, carvacrol was retained 39% more when ground leaves were added.


Assuntos
Culinária/métodos , Ácidos Hidroxâmicos/química , Monoterpenos/química , Timol/química , Cimenos , Humanos , Ácidos Hidroxâmicos/análise , Modelos Moleculares
8.
Food Chem Toxicol ; 43(11): 1647-55, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15975702

RESUMO

Dietary intake of arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) by the population of Santiago (Chile) was determined using a Total Diet Study in the market basket modality. After conducting a survey of the foods consumed in the last 24 h, the most consumed food products were included in the basket. Subsequently, they were cooked or prepared according to typical Chilean procedures and grouped into 17 food categories according to their chemical characteristics. The fish and shellfish group had the highest contents of As (1351 ng/g wet weight, ww), Cd (277 ng/g ww), and Hg (48 ng/g ww), while the sugar group had the highest content of Pb (251 ng/g ww). For a person with a body weight of 68 kg, the dietary intakes of As (77 microg/day), Cd (20 microg/day), Hg (5 microg/day), and Pb (206 microg/day) are lower than the provisional tolerable weekly intake values established by the FAO/WHO. Consequently, the total intakes of As, Cd, Hg, and Pb in Santiago (Chile) are within the limits estimated as safe.


Assuntos
Arsênio/análise , Cádmio/análise , Inquéritos sobre Dietas , Chumbo/análise , Mercúrio/análise , Chile/epidemiologia , Análise de Alimentos , Indicadores e Reagentes , Carne/análise , Controle de Qualidade , Alimentos Marinhos/análise , Espectrofotometria Atômica , Inquéritos e Questionários
9.
J Agric Food Chem ; 50(3): 642-7, 2002 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-11804542

RESUMO

High levels of arsenic are found in the soil and water of the Second Region in Chile as a result of natural causes. Total and inorganic arsenic contents were analyzed in the edible part of 16 agricultural products (roots, stems, leaves, inflorescences, and fruits) grown in this area. The total arsenic contents varied in the range 0.008-0.604 microg g(-1) of wet weight (ww), below the maximum level allowed by Chilean legislation (1 microg(-1) of ww). Inorganic arsenic contents (range = 0.008-0.613 microg(-1) of ww) represented between 28 and 114% of total arsenic. The concentrations of total and inorganic arsenic found in edible roots and leaves were higher than those found in fruit. The highest concentrations were found in a sample of spinach. High quantities of this vegetable would have to be consumed (250 g/day) to reach the Provisional Tolerable Weekly Intake for inorganic arsenic. The vegetable group may make a considerable contribution to the total intake of inorganic arsenic.


Assuntos
Arsênio/análise , Verduras/química , Arsênio/administração & dosagem , Chile , Contaminação de Alimentos/análise , Humanos
10.
J Agric Food Chem ; 52(6): 1773-9, 2004 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-15030245

RESUMO

Total and inorganic As contents of cooked vegetables obtained from an arsenic endemic area of Chile were analyzed. Inorganic As intake from those foods, bread, and water was estimated. The study was performed in two different periods, in which the water used by the population for drinking and cooking purposes contained 0.572 (first period) or 0.041 microg mL(-)(1) (second period). In the first period, the FAO/WHO reference intake was exceeded by all of the persons interviewed. In the second period, the reference intake was exceeded by all of the persons interviewed ages 13-15. The foods studied contributed 4% (first period) or 25% (second period) of the inorganic As intake. The results show the contribution of food to inorganic As intake and the risk to which those ages 15 or younger are exposed.


Assuntos
Arsênio/administração & dosagem , Pão/análise , Dieta , População Rural , Verduras/química , Água/análise , Arsênio/análise , Chile , Temperatura Alta , Humanos
11.
Food Chem Toxicol ; 50(3-4): 744-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22138359

RESUMO

Chile is one of the major producers of phytocolloids extracted from seaweed. Multicellular algae are considered to be primary accumulators of arsenic. We analyzed 14 species of algae belonging to the groups Rhodophyceae (10), Phaeophyceae (3) and Chlorophyceae (1) from different coastal zones of Chile in 2003-2004. Dry ashing mineralization (for total As) and acid digestion (for inorganic As) together with quantification by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS) were employed. In general, total arsenic concentrations varied between 3.0 and 68 mg kg(-1), whereas inorganic arsenic concentrations ranged between 0.15 and 1.06 mg kg(-1). The algal species Durvillaea antarctica and Porphyra columbina, used for direct human consumption, did not have inorganic arsenic levels that represent a health risk to consumers. Among species used for phytocolloids production, such as Macrocystis piryfera, Gracilaria chilensis and Gigartina skottsbergii, observed levels of inorganic arsenic were greater than 1 mg kg(-1), the limit value established by the regulations of some countries. Among the 14 species of algae tested, inorganic arsenic levels were between 0.8% and 13% of the total arsenic concentrations; that is, arsenic present in these algae was found primarily as organic arsenic.


Assuntos
Arsênio/análise , Alga Marinha/química , Arsênio/metabolismo , Chile , Exposição Ambiental , Humanos , Alga Marinha/metabolismo , Espectrofotometria Atômica
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