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1.
Molecules ; 23(7)2018 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-29997337

RESUMO

Green tea infusions are one of the most popular beverages consumed across the world, especially is Asian countries. Green tea quality is primarily based on catechin content, however, the concentration of elements could also significantly influence its biological properties and thus quality and safety. The main purpose of the present study was the evaluation of catechin, antioxidant activity and metal content (K, Na, Ca, Mg, Fe, Mn, Cu, Zn, Cr, Pb, Cd and Ni) in different green tea types cultivated in Japan, Sri Lanka, South Korea, India, China and Japan. The chemical analysis of samples was performed using LC-ESI-Q-TOF-MS for organic constituents and atomic absorption spectrometry (flame and electrothermal) method for inorganic ones. The obtained results were subjected to chemometric elaboration. EGC (213 mg/100 mL of the tea infusion in South Korean Jeoncha) and EGCG (124 mg/100 mL in Japanese Sencha) were the dominant catechins in all green tea samples. Chinese and Indian green tea samples contained the highest concentration of toxic heavy metals, however these values were far below appropriate limitations for green teas. PCA revealed significant similarities between Japanese samples and Korean Jeoncha. In general the latter one was evaluated to have the best quality based on the investigated parameters.


Assuntos
Catequina/análise , Metais/análise , Análise de Componente Principal , Chá/química , Antioxidantes/análise , Benzotiazóis/química , Catequina/química , Dieta , Ácido Gálico/análise , Reprodutibilidade dos Testes , Espectrofotometria Atômica , Ácidos Sulfônicos/química , Oligoelementos/análise
2.
Int J Mol Sci ; 18(2)2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28230740

RESUMO

The usefulness of ginger in the food industry and pharmacotherapy is strictly related to its content of various components. The study elucidates the chemical composition of Zingiber officinale rhizomes cultivated on ecological plantations on Shikoku Island (Japan). GC-MS analysis of terpene content, LC-MS determination of phenolic content, and the determination of 12 elements using AAS spectrometry were performed to give more detailed insight into the samples. Ninety-five percent of terpene composition was elucidated, with zingiberene as the most abundant sesquiterpene (37.9%); the quantification of gingerols and shogaols was performed, showing the highest contribution of 6-gingerol (268.3 mg/kg); a significant K (43,963 mg/kg of dry mass) and Mn (758.4 mg/kg of dry mass) content was determined in the elemental analysis of the rhizomes and low concentration of toxic elements (Cd, Ni and Pb) remaining below the safe level values recommended by European Commission Directives. The main phenolic compound was (6)-gingerol, which is characteristic of fresh rhizomes and is responsible for their taste and aroma. Surprisingly, high amounts of (6)-shogaol were determined, even though this phenolic compound usually occurs in old or processed material and not in fresh rhizomes. Sesquiterpenes were the major fraction of volatiles. The highest concentrations were determined for α-zingiberene, ß-sesquiphellandrene, (E,E)-α-farnesene, geranial, and ar-curcumene. The volatiles composition of ginger cultivated on Shikoku Island is specific and strongly differs from plants cultivated in China, Nigeria, or Australia. The elemental composition of ginger rhizomes grown in ecological plantations is more beneficial for human health compared to products grown in normal cultivars, as the products contain high amounts of potassium and manganese and are characterized by low sodium content and lower levels of toxic heavy metals.


Assuntos
Cromatografia Líquida , Cromatografia Gasosa-Espectrometria de Massas , Extratos Vegetais/química , Rizoma/química , Zingiber officinale/química , Metabolômica/métodos , Metais Pesados/química , Terpenos/química , Oligoelementos/química , Compostos Orgânicos Voláteis/química
3.
PLoS One ; 15(12): e0244435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33373389

RESUMO

The aim of this study was to determine the effect of the age of trees, daily sap volume as well as the term of tapping birch sap collected in the forest environment on the content of selected minerals (zinc, copper and manganese) and heavy metals (lead, nickel, chromium and cadmium). The study was performed on material taken from two stands (aged 34 and 84 years) in a moist broadleaved forest habitat with a dominant share of silver birch (Betula pendula Roth). The research results confirmed the presence of both nutritional essential minerals and hazardous heavy metals in the birch sap. At the same time, the content of minerals and heavy metals was found to be very variable and the differences between their concentrations, recorded on the same day of collecting in several trees of the same age group, can be even several dozen times higher. Depending on the examined elements, the factors influencing their content vary. The age of the trees determines only the manganese content; daily sap volume significantly affects the content of manganese and copper, and date of collection differentiates the content of zinc, lead, nickel and cadmium. The results may be interesting in the context of developing procedures for collecting birch sap for the purpose of obtaining raw material with beneficial nutritional values and a high level of health safety. For this reason, our recommendation for guaranteeing the health safety and high nutritional value of birch sap is to combine batches of raw material taken from as many trees as possible, and at the same time to publicize the fact that collecting birch sap from just one single tree may result in a raw material that is both dangerous and has no nutritional benefits.


Assuntos
Betula/fisiologia , Metais Pesados/análise , Minerais/análise , Exsudatos de Plantas/química , Bebidas/análise , Florestas , Polônia
4.
Materials (Basel) ; 11(4)2018 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-29565297

RESUMO

Polyaniline (PANI) is one of the best known conductive polymers with multiple applications. Recently, it was also used in separation techniques, mostly as a component of composites for solid-phase microextraction (SPME). In the present paper, sorbent obtained by in situ polymerization of aniline directly on silica gel particles (Si-PANI) was used for dispersive solid phase extraction (d-SPE) and matrix solid-phase extraction (MSPD). The efficiency of both techniques was evaluated with the use of high performance liquid chromatography with diode array detection (HPLC-DAD) quantitative analysis. The quality of the sorbent was verified by Raman spectroscopy and microscopy combined with automated procedure using computer image analysis. For extraction experiments, triterpenes were chosen as model compounds. The optimal conditions were as follows: protonated Si-PANI impregnated with water, 160/1 sorbent/analyte ratio, 3 min of extraction time, 4 min of desorption time and methanolic solution of ammonia for elution of analytes. The proposed procedure was successfully used for pretreatment of plant samples.

5.
Talanta ; 165: 351-356, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28153266

RESUMO

Trace analysis plays an important role in medicine for diagnosis of various disorders; however, the appropriate sample preparation is required mostly including mineralization. Although graphite furnace atomic absorption spectrometry (GF AAS) allows the investigation of biological samples such as blood, serum, and plasma without this step, it is rarely used for direct analysis because the residues of the rich organic matrix inside the furnace are difficult to remove and this may cause spectral/matrix interferences and decrease the lifetime of the graphite tube. In our work, the procedure for determination of Se, Cr, Mn, Co, Ni, Cd and Pb with the use of the high resolution continuum source GF-AAS technique in whole blood samples with minimum sample pre-treatment was elaborated. The pyrolysis and atomization temperature as well as the time of signal integration were optimized to obtain the highest intensity and repeatability of the analytical signal. Moreover, due to the apparatus modification, an additional step was added in the for graphite furnace temperature program with minimal argon flow and maximal flow of air during pyrolysis stage to increase the oxidative condition for better matrix removal. The accuracy and precision of the optimized method was verified using certified reference material (CRM) Seronorm Trace Elements Whole Blood L-1 and the developed method was applied for trace analysis of blood samples from volunteer patients of the Orthopedics Department.


Assuntos
Grafite/química , Espectrofotometria Atômica/métodos , Oligoelementos/sangue , Calibragem , Voluntários Saudáveis , Humanos , Padrões de Referência
6.
Oxid Med Cell Longev ; 2017: 1891849, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29181123

RESUMO

The methanol extracts from three populations of Carlina vulgaris L. were examined for the chlorogenic acid content, mineral content, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity. Two populations originated from natural nonmetallicolous habitats (NN (populations from Nasilów) and NP (populations from Pinczów)), and one metallicolous population (MB) was collected from Boleslaw waste heap localized at the place of former open-cast mining of Ag-Pb and Zn-Pb ores dating back to the 13th century and 18th century, respectively. The level of Zn, Pb, Cd, Fe, Ni, and Mn was significantly higher in the root and leaves of MB plants as a result of soil contaminations compared to those of the NN and NP ones. The highest antioxidant potency has been showed by the plants growing in a nonmetallicolous habitat. The flower head extracts obtained from the nonmetallicolous populations also contained the largest amount of chlorogenic acid, whereas the lowest was determined in the roots (ca. 2-3.5 mg/g and 0.2-0.4 mg/g of air-dry weight, resp.). These studies provide important information on the influence of a habitat on the quality of herbal materials and the content of the biologically active primary and secondary metabolites.


Assuntos
Antioxidantes/metabolismo , Compostos Fitoquímicos/química , Folhas de Planta/química
7.
J Trace Elem Med Biol ; 29: 116-22, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25194955

RESUMO

OBJECTIVE: To determine serum and urinary selenium (Se) levels in children with and without obesity, and to assess if Se influences the risk of obesity. SUBJECTS AND METHODS: High-resolution-continuum source-atomic absorption spectrometry (HR-CS-AAS) was used to determine the content of Se in 80 children (age 6-17; 40 boys, 40 girls). Correlations between variables were tested with the use of Spearman's correlation coefficient. U Mann-Whitney test was applied to assess the difference of Se contents in samples. Measured metabolic risk factors (blood pressure, glucose level, triglycerides (TG), low-density lipoprotein (LDL), high-density lipoprotein (HDL), and total cholesterol), age, gender, and BMI were correlated. Logistic regression models were fitted to identify predictors of obesity interacting with selenium content in serum and urine, separately. RESULTS: Obese children, regardless of gender, had lower Se content. Se level in serum (p=0.001, OR 0.74, 95%CI 0.62-0.88) and total cholesterol (p=0.001, OR 1.19, 95%CI 1.08-1.31) were the independent factors significantly influencing the risk of obesity in children. Two separate models were observed for Se in urine: (i) Se level (p<0. 0001, OR 0.70, 95%CI 0.58-0.84) and glucose level (p<0.0001, OR 1.22, 95%CI 1.10-1.35), and (ii) Se level (p=0.002, OR 0.60 95%CI 0.43-0.83) and total cholesterol level (p=0.003, OR 1.16, 95%CI 1.05-1.28). CONCLUSION: The current study suggests a possible role of Se in obesity. Further research needs to be performed to check if obese children are an at-risk group for Se deficiency.


Assuntos
Obesidade/sangue , Obesidade/urina , Selênio/sangue , Selênio/urina , Adolescente , Estudos de Casos e Controles , Criança , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Análise Multivariada
8.
J Agric Food Chem ; 62(23): 5248-52, 2014 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-24835388

RESUMO

Soy (Glycine max (L.) Merr.) is an annual plant cultivated worldwide mostly for food. Moreover, due to its pharmacological properties it is widely used in pharmacy for alleviating the symptoms of osteoporosis. The aim of the present study was to investigate the biofortification of soy treated with various concentrations of strontium. Soy was found to have a strong capacity to absorb Sr(2+) (bioconcentration factor higher than 1). A positive linear correlation (R(2) > 0.98) between the amount of strontium in the growth medium and its content in the plant was also observed. Moreover, at a concentration of 1.5 mM, strontium appeared to be nontoxic and even stimulated plant growth by approximately 19.4% and 22.6% of fresh weight for shoots and roots, respectively. Our research may be useful to obtain vegetable products or herbal preparations containing both phytoestrogens and strontium to prevent postmenopausal osteoporosis.


Assuntos
Alimentos Fortificados/análise , Glycine max/química , Estrôncio/análise , Feminino , Humanos , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/prevenção & controle , Glycine max/crescimento & desenvolvimento , Glycine max/metabolismo , Estrôncio/metabolismo
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