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1.
Molecules ; 26(3)2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33499197

RESUMO

Teas and various herbal teas are well-known beverages and are commonly consumed around the world. In this study, we focused on kuromoji tea. Kuromoji is a deciduous shrub of the Lauraceae family, and the plucked leaves and branches have been drunk as a tea in production areas for a long time. However, no studies have investigated the subjective and physiological effects of kuromoji tea. In this study, the effects of kuromoji tea were examined on the basis of the measurements of heart rate variability and cerebral blood flow, core body temperature and subjective assessments. Moreover, the results of this study showed that a pleasant subjective feeling could be obtained by sniffing the aroma of kuromoji teas, especially tea leaves. It was also found that the aroma of kuromoji teas has the potential to stimulate saliva secretion and increase subjective and physiological excitements in the oral cavity. 1,8-Cineole, linalool, terpinen-4-ol, carvone and geraniol were determined in both kuromoji leaves and branches. In this study, the beneficial effects of kuromoji teas when drunk conventionally were investigated.


Assuntos
Lindera/química , Odorantes/análise , Chás de Ervas/análise , Temperatura Corporal , Estudos Cross-Over , Cromatografia Gasosa-Espectrometria de Massas , Frequência Cardíaca , Humanos , Inalação , Japão , Masculino , Percepção Olfatória/fisiologia , Oxiemoglobinas/metabolismo , Microextração em Fase Sólida , Escala Visual Analógica , Adulto Jovem
2.
Food Chem ; 346: 128929, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33450644

RESUMO

Linden trees are a source of food products called lime flowers (Tiliae flos), traditionally used in the form of infusion for the treatment of feverish colds and coughs. Lime flowers should include flowers of Tilia cordata Mill, T.x europaea L., and T. platyphyllos Scop. or a mixture of these. The aim of current research was to establish a fast, sensitive HPTLC (high-performance thin-layer chromatography) method that would allow the differentiation of material obtained from five species of lime occurring in Europe. The fingerprints for distinguishing these species were established, as well as a key for identification based on a visual evaluation of chromatograms. The results obtained were also subjected to chemometric analyses. It was shown that each species contains characteristic compounds i.e. linarin that can be used for their identification. The method developed can, in theory, be introduced for the quality control or authentication of linden flowers on the European market.


Assuntos
Cromatografia em Camada Delgada , Flores/química , Análise de Alimentos/métodos , Chás de Ervas/análise , Tilia/química , Controle de Qualidade
3.
Food Chem ; 337: 127659, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32781355

RESUMO

In this study, 3,3-bis(4-hydroxy-3-((E)-((4-hydroxyphenyl)imino)methyl) phenyl)isobenzofuran-1(3H)-one (HMBP) was designed as a ''turn-on″ fluorogenic chemosensor to detect Al3+. Studies were performed in C2H5OH-HEPES (v/v, 9/1, pH 7.0) media at λem = 475 nm. The LOD value was found to be 0.113 µM. The stoichiometric ratio of HMBP-Al3+ was determined as 1:2 by Job's plot and ESI-MS as well as 1H NMR titration. The binding constant of chemosensor HMBP with Al3+ from the Benesi-Hildebrand equation was determined to be 1.21 × 108 M-1. The quantum (Φ) yields were obtained as 0.040 and 0.775 for the chemosensor HMBP and HMBP-Al3+, respectively. The response of the chemosensor HMBP towards Al3+ was attributed to the strategies of blocking the photo-induced electron transfer (PET) and CN isomerisation mechanisms. Finally, the sensing of the chemosensor HMBP for the determination of Al3+ in real food samples, drinking waters and herbal teas, were employed.


Assuntos
Alumínio/análise , Água Potável/análise , Corantes Fluorescentes/química , Fenolftaleína/química , Chás de Ervas/análise , Análise de Alimentos/métodos , Isomerismo , Espectroscopia de Ressonância Magnética , Sensibilidade e Especificidade
4.
Environ Geochem Health ; 42(9): 2853-2863, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32166521

RESUMO

The total mean ∑[Formula: see text] in samples were from 75.3 to 387.0 ng/g dry weight (d.w) and showed high value in black dry tea, followed by herbal, oolong, and green tea. The mean ∑[Formula: see text] (a combination of benz[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene) values were 54.3 ng/g, 16.4 ng/g, 14.2 ng/g, and 6.6 ng/g for black, herbal, green, and oolong teas, respectively. Concentration for benzo[a]pyrene (BaP) was from 0.4 to 35.8 ng/g, and the BaP equivalent concentration values ranged from 0.3 to 48.1 ng/g. There was only 1 black tea sample that BaP concentration exceeded the maximum level according to European Union (EU) standards. Tea samples marketed in Vietnam showed insignificant difference with the samples from other origins by same analytical method. Black teas showed high PAHs contents in dry tea samples but the released percentage of sum of PAHs from tea-to-tea infusion was lower than that in other tea type samples. The released percentages of PAH4 from tea-to-tea infusion were 40.7, 15.4, and 1.9 for green, herbal, and black tea. High temperature in black tea manufacturing processes might reduce essential oil content in tea that might effect on the PAHs partially release into the infusion. Indeed, based on EU regulations, we may conclude that tea consumers are safe in risk of exposure to PAHs obtained from teas.


Assuntos
Exposição Dietética/análise , Contaminação de Alimentos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Chá/química , Benzo(a)pireno/análise , Camellia sinensis/química , Crisenos/análise , Exposição Dietética/efeitos adversos , Fluorenos/análise , Humanos , Folhas de Planta/química , Medição de Risco/métodos , Chás de Ervas/análise , Vietnã
5.
Food Chem ; 318: 126512, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32135418

RESUMO

E Se tea, prepared from the leaves of Malus toringoides (Rehd.) Hughes, is a traditional beverage, but there is little known about its chemical substances. This paper is aimed to investigate the chemical composition, antioxidant, and cytoprotective activities of the extract and fractions from E Se tea. Sixteen compounds were characterized by UHPLC-ESI-HRMS/MS. Phloridzin was the main compound, especially in ethyl acetate fraction (EAF). Moreover, EAF had the highest total phenolic and flavonoid contents with 197.54 ± 7.52 mg gallic acid equivalents/g extract and 85.94 ± 5.39 mg rutin equivalents/g extract, respectively, and exhibited the strongest antioxidant capacity (DPPH: IC50 = 54.91 ± 3.38 µg/mL; ABTS: IC50 = 98.08 ± 6.92 µg/mL). Different fractions of E Se tea, especially EAF, significantly inhibited intracellular ROS generation, reduced cell apoptosis, and decreased oxidative stress damage in H2O2-induced HepG-2 cells. Therefore, the obtained results highlight that E Se tea is a promising source for functional beverage or nutritional foods.


Assuntos
Malus/química , Fenóis/análise , Chás de Ervas/análise , Antioxidantes/química , Antioxidantes/farmacologia , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Células Hep G2 , Humanos , Peróxido de Hidrogênio/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/análise , Extratos Vegetais/química , Folhas de Planta/química , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
6.
Sci Rep ; 10(1): 4709, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-32170197

RESUMO

A simple and effective method for determining five pyrethroid residues in herbal tea by ultrasound-enhanced temperature-controlled (UETC) ionic liquid dispersive liquid-liquid microextraction (IL-DLLME) coupled with high performance liquid chromatography-diode array detection (HPLC-DAD) was developed. The use of ultrasonication and heating improved the ability of the ionic liquid to extract the analytes. Various parameters that affect the extraction efficiency were investigated and optimized using single factor experiments and response surface design. The optimum conditions of the experiment were 121 µL of [HMIM][PF6] (extraction solvent), 794 µL of acetonitrile (dispersive solvent), a heating temperature of 40°C, a sonication time of 3.6 min and a pH of 2.9. Under optimized conditions, the linearity was in the range of 0.05-5 mg L-1 with correlation coefficients above 0.9993. The limits of detection and quantification were 1.25-1.35 µg L-1 and 5 µg L-1, respectively. The mean recoveries of the five pyrethroids ranged from 74.02% to 109.01%, with RSDs below 9.04%. The proposed method was reliable for the analysis of pyrethroids in Chinese herbal tea.


Assuntos
Contaminação de Alimentos , Inseticidas/análise , Líquidos Iônicos/química , Piretrinas/análise , Chás de Ervas/análise , Temperatura , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Microextração em Fase Líquida , Reprodutibilidade dos Testes , Fatores de Risco , Solventes/química , Sonicação/métodos
7.
Food Chem ; 310: 125840, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31806390

RESUMO

Despite the extensive use of Polygonum chinense (PC) as a detoxifying ingredient of Chinese cool tea, the efficacy of different PC varieties remains underexplored. Herein, we compare the chemical profiles and antioxidant/anti-inflammatory activities of the aqueous extracts of two PC varieties, namely P. chinense var. chinense (PCC) and P. chinense var. hispidum (PCH). Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MSMS) and multivariate analysis are used to rapidly identify extract components, while DPPH radical scavenging and xylene-induced mice ear edema assays are used to evaluate antioxidant and anti-inflammatory activities, respectively. Correlation analysis reveals that ellagic acid and quercitrin contents are positively correlated with the magnitude of the anti-inflammatory effect, and the adopted technique is concluded to allow for the rapid discrimination of PC varieties used in Chinese cool tea formulations.


Assuntos
Polygonum/química , Chás de Ervas/análise , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , China , Cromatografia Líquida de Alta Pressão/estatística & dados numéricos , Ácido Elágico/análise , Qualidade dos Alimentos , Masculino , Camundongos Endogâmicos BALB C , Extratos Vegetais/química , Quercetina/análogos & derivados , Quercetina/análise , Quercetina/farmacologia , Espectrometria de Massas em Tandem , Xilenos/toxicidade
8.
J Sci Food Agric ; 100(5): 1904-1912, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31825526

RESUMO

BACKGROUND: A new solvent, deep eutectic solvent, in which there is growing interest, has been prepared and used as an extraction solvent in the dispersive liquid-liquid method of microextraction. To prepare the solvent, dichloroacetic acid, l-menthol, and n-butanol are mixed at a molar ratio of 4:1:1 and the deep eutectic solvent is formed after heating. Then a dispersive liquid-liquid microextraction method using the prepared solvent is used for the extraction and preconcentration of some pesticides from an aqueous sample. To carry out the procedure, the deep eutectic solvent is mixed with methanol and rapidly injected by a syringe into the aqueous sample containing the analytes. After centrifuging, an aliquot of the sedimented phase is injected into the gas chromatograph. The influence of several variables on the extraction efficiency was investigated and optimized. RESULTS: Extraction recoveries and enrichment factors were obtained in the ranges of 53-86% and 1760-2853, respectively. The intra- (n = 6) and inter-day (n = 5) precision of the method was satisfactory, with relative standard deviations ≤ 7% obtained at two concentrations of 10 and 50 µg L-1 of each analyte. Moreover, detection and quantification limits for the target analytes were obtained in the ranges of 0.11-0.23 and 0.38-0.74 µg L-1 , respectively. CONCLUSION: Different samples, including green tea, rose water, lemon balm, mint, and pussy willow distillates were analyzed successfully using the method that was developed, and chlorpyrifos was found in rose water at a concentration of 17 ± 1 µg L-1 (n = 3). © 2019 Society of Chemical Industry.


Assuntos
Microextração em Fase Líquida/métodos , Resíduos de Praguicidas/isolamento & purificação , Chá/química , Chás de Ervas/análise , Cromatografia Gasosa , Contaminação de Alimentos/análise , Limite de Detecção , Microextração em Fase Líquida/instrumentação , Resíduos de Praguicidas/análise , Solventes/química
9.
Food Chem ; 310: 125825, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31753689

RESUMO

Preconcentration of cobalt was carried out with deep eutectic solvent based liquid phase microextraction (DES-LPME) for trace determination by a slotted quartz tube (SQT) attached flame atomic absorption spectrometry (FAAS) system. Choline chloride and phenol in a 1:2 M ratio was used as a green solvent to extract cobalt from the aqueous sample solution. Key parameters influencing the extraction efficiency of cobalt were examined and optimized. Under the conditions optimized, the linear dynamic range was found between 5.0 and 50 µg L-1, and the limits of detection and quantification (LOD and LOQ) were calculated as 2.0 and 6.6 µg L-1, respectively. The detection power of the conventional FAAS was improved upon by 67 folds using the optimized DES-LPME-SQT-FAAS method. The developed analytical method was successfully applied for the determination of cobalt in linden tea samples and the recovery results obtained for different spiked concentrations (20, 30 and 40 µg L-1) were remarkable (≈100%).


Assuntos
Cobalto/análise , Análise de Alimentos/métodos , Microextração em Fase Líquida/métodos , Espectrofotometria Atômica/métodos , Cobalto/isolamento & purificação , Química Verde , Limite de Detecção , Quartzo/química , Solventes/química , Espectrofotometria Atômica/instrumentação , Chás de Ervas/análise , Tilia/química , Água/química
10.
Ecotoxicol Environ Saf ; 187: 109859, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31677573

RESUMO

Chrysanthemum (Dendranthema grandiflora) flowers are consumed as a popular, traditional herbal tea worldwide. During tea infusion with hot water pesticide residues in chrysanthemum flowers can be transferred into tea solution, posing potential health risks to consumers. Using greenhouse chrysanthemum this study systematically investigated the transfer of metalaxyl-M, fludioxonil, cyantraniliprole, thiamethoxam, and clothianidin (a major metabolite of thiamethoxam) from dry chrysanthemum flowers to tea solution at a range of infusion repetitions, duration and water temperature. The tested pesticides were released into tea solution at varying degrees, and the maximum transfer percentage was 59.9%, 9.8%, 29.4%, 88.2% and 68.4% for metalaxyl-M, fludioxonil, cyantraniliprole, thiamethoxam, and clothianidin, respectively. The transfer of pesticides into tea solution generally increased with increasing pesticide water solubility, water temperature, infusion duration, and pesticide concentrations in dry chrysanthemum flowers, but decreased with increasing octanol-water partition coefficient and the number of infusion repetitions. Risk quotient for pesticide intake via consuming tea solution of chrysanthemum flowers (one and two times of recommended pesticide dosages) ranged from <0.00003 to 0.0924, indicating a low health risk. This study provides useful information for risk assessment of pesticide residues in greenhouse chrysanthemum flowers and may help establish realistic maximum residue limit of pesticides in chrysanthemum flowers and tea solution.


Assuntos
Chrysanthemum/química , Flores/química , Contaminação de Alimentos/análise , Resíduos de Praguicidas/análise , Chás de Ervas/análise , Medição de Risco , Solubilidade
11.
Food Chem ; 302: 125336, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31419772

RESUMO

This study reports a stepwise optimization of switchable liquid-liquid microextraction (SLLME) for cobalt determination by flame atomic absorption spectrometry (FAAS) coupled with a slotted quartz tube (SQT). The main purpose of this study was to develop an accurate and sensitive analytical method for cobalt. Extraction method was used to separate and preconcentrate cobalt from sage tea and vitamin B12 samples after complexing with a Schiff base ligand. 107.7 folds enhancement in detection power under the optimum conditions was recorded with respect to direct FAAS. This enhancement correlated to 3.1 µg/L limit of detection and 10 µg/L limit of quantification. The SLLME-SQT-FAAS method was linear over a broad concentration range and low %RSD values established high precision for the method. Appreciable percent recovery results (94-108%) obtained from spiked sage sample and from cobalamin also validated the accuracy of the method.


Assuntos
Cobalto/análise , Microextração em Fase Líquida/métodos , Espectrofotometria Atômica/métodos , Chás de Ervas/análise , Vitamina B 12/análise , Limite de Detecção , Quartzo , Reprodutibilidade dos Testes , Salvia officinalis/química , Bases de Schiff/química , Espectrofotometria Atômica/instrumentação , Vitamina B 12/química
12.
Food Res Int ; 125: 108519, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31554050

RESUMO

Variation in the bitter taste of Cyclopia genistoides (honeybush) herbal tea and reported modulation between its major xanthones, mangiferin and isomangiferin, prompted further investigation into the potential modulatory effects of honeybush phenolics. Combinations of crude benzophenone (BF)-, xanthone (XF)-, and flavanone (FF)-rich fractions and their major individual phenolic compounds were analysed by descriptive sensory analysis. The fractions were prepared from a bitter, hot water extract of green C. genistoides. Fraction BF, which is below the bitter threshold (intensity 10 on 100-point scale), enhanced the bitter intensity of XF and FF slightly (p < 0.05), although none of the major individual benzophenones retained this bitter enhancing effect. On the contrary, 3-ß-d-glucopyranosyl-4-ß-d-glucopyranosyloxyiriflophenone, the major benzophenone in BF, significantly (p < 0.05) decreased the bitter taste of XF, at a low concentration, whereas FF suppressed the bitter intensity of XF and mangiferin, the major xanthone present in XF. Hesperidin, however, had no effect on the bitter intensity of XF. In contrast, (2S)-5-[α-L-rhamnopyranosyl-(1→2)-ß-d-glucopyranosyloxy]-naringenin, the major compound of FF, significantly (p < 0.05) enhanced the bitter taste of XF when added at concentrations comparable to that of 'fermented' honeybush tea infusions. The concentration-dependence of these bitter taste interactions may be responsible for the variable bitter intensity of C. genistoides herbal tea.


Assuntos
Benzofenonas/análise , Fabaceae/química , Flavanonas/análise , Chás de Ervas/análise , Cromatografia Líquida de Alta Pressão , Humanos , Paladar/fisiologia
13.
Anal Bioanal Chem ; 411(27): 7233-7249, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31511948

RESUMO

Pyrrolizidine alkaloids (PA) and PA-N-oxides (PANO) are a large group of secondary plant metabolites comprising more than 660 compounds. Exhibiting geno- and hepatotoxic properties, they are responsible for multiple cases of food and feed poisoning over the last 100 years. For food and feed safety reasons, relevant PA/PANO should be monitored extensively in the main sources of PA/PANO intake. In this study, a sensitive analytical method was developed for detecting a broad range of 44 commercially available PA/PANO compounds, and in-house validation procedures were performed for several (herbal) teas. Various extraction solvents and procedures, as well as solid phase extraction materials for sample clean-up and analyte concentration, were tested to establish the methods' efficiency and effectiveness. Chromatographic conditions were optimised to obtain the best possible separation of isomers for the 44 PA/PANO analytes. The final method was proven very sensitive and accurate, with detection limits ranging from 0.1 to 7.0 µg/kg and precisions between 0.7 and 16.1%. For 40 of the analytes, the recovery rates ranged from 60.7 to 128.8%. The applicability and trueness of the method were examined by analysing tea samples from a local supermarket and comparing them to a reference material. At least one PA/PANO analyte was detected in 17 of the 18 samples under investigation, and the sum contents of the samples ranged from 0.1 to 47.9 µg/kg. Knowledge of the PA/PANO composition in a sample can be used to indicate the botanical origin of the impurity and, thus, the geographical region of cultivation.


Assuntos
Cromatografia Líquida/métodos , Alcaloides de Pirrolizidina/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Chá/química , Chás de Ervas/análise , Contaminação de Alimentos/análise , Limite de Detecção , Reprodutibilidade dos Testes
14.
J Food Biochem ; 43(11): e13026, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31463942

RESUMO

The nutrient composition of Myrothamnus flabellifolius leaf tea extract (MLTE) and its protective effect against oxidative hepatic cell injury were evaluated. Gallic acid, caffeic acid, ferulic acid, methyl gallate, and epicatechin were identified in MLTE by high-performance liquid chromatography (HPLC). The tea extract showed an appreciable nutritional content of proximate, sugar, vitamin E, monounsaturated fatty acids, omega 6 and 9 unsaturated fatty acids, as well as considerable amounts of various mineral elements. Nineteen amino acids were found. Moreover, MLTE exhibited potent in vitro antioxidant activities, presumably because of its richness in polyphenols (gallic acid and ferulic acid) and vitamin E. In Chang liver cells, pretreatment with MLTE suppressed oxidative lipid peroxidation (IC50  = 113.11 µg/ml) and GSH depletion (IC50  = 70.49 µg/ml) without causing cytotoxicity. These data support the local consumption of M. flabellifolius herbal tea, which may be used against oxidative stress-induced diseases while providing the body with necessary nutrients. PRACTICAL APPLICATION: Herbal teas are one of the most consumed beverages in the world today, due to their refreshing taste and additional health benefits. Myrothamnus flabellifolius herbal tea is a widely used traditional herbal tea in Southern Africa with potentials for commercialization due to its pleasant flavor. This study, for the first time, reported the nutritional composition of the leaf decoction of M. flabellifolius and its protective effect on hepatic oxidative insults. These results can inform the dietary and nutritional use of the tea for optimum benefits, as well as provide preliminary scientific validation of the use of the herbal tea as an antioxidant beverage with good nutritional value.


Assuntos
Antioxidantes/análise , Fígado/metabolismo , Magnoliopsida/química , Preparações de Plantas/análise , Substâncias Protetoras/análise , Chás de Ervas/análise , Antioxidantes/farmacologia , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/lesões , Valor Nutritivo , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/química , Preparações de Plantas/farmacologia , Substâncias Protetoras/farmacologia
15.
Food Funct ; 10(9): 5939-5951, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31469370

RESUMO

In order to characterize and study the bioactivities of individual plant species and to determine how these characteristics are modified when preparing blends, five different plant species were selected: Erica australis L., Genista tridentata L., Melissa officinalis L., Mentha spicata L., and Prunella vulgaris L. Infusions prepared from each plant species and from three selected mixtures were analyzed in terms of nutritional values, phenolic compositions, and bioactive properties (antioxidant, antimicrobial, cytotoxic, and anti-inflammatory activities). The major compound detected in M. officinalis, M. spicata, and P. vulgaris infusions was rosmarinic acid, whilst in E. australis and G. tridentata flavonoid derivatives such as quercetin and genistein were identified. P. vulgaris and M. officinalis presented the best results in TBARS and OxHLIA assays, respectively. M. spicata and all mixtures presented anti-inflammatory activity. M. spicata showed the best cytotoxic properties and antimicrobial activity, and none of the infusions showed hepatotoxicity for non-tumour cells.


Assuntos
Genista/química , Melissa/química , Mentha spicata/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Prunella/química , Chás de Ervas/análise , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Flavonoides/química , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Fenóis/química , Fenóis/farmacologia , Células RAW 264.7
16.
Plant Foods Hum Nutr ; 74(3): 266-276, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31243622

RESUMO

Herbal teas are used as therapeutic vehicles in many forms of traditional medicine and are a popular global beverage. The purpose of this scoping review was to examine the evidence relating to the clinical efficacy and safety of herbal teas, and to identify the main research themes and gaps in knowledge to inform further work. A scoping review methodology was followed that set out the research question and described the sourcing, selection and analysis of studies. Overall, a total of 145 research publications were retrieved from global bibliographic databases, and after applying exclusion criteria, 21 remained. These studies looked at herbal tea use in female health, diabetes, heart disease and weight loss, with plant species including lavender, chamomile, fenugreek, stinging nettle, spearmint, hibiscus, yerba maté, echinacea and combinations of herbs. Observational studies explored associations between herbal tea consumption and cancer risk, liver health, and the risks linked to the consumption of environmental contaminants in the plant material. Despite plant materials being the basis for drug discovery, and the popularity of herbal teas, the number of articles exploring clinical efficacy and safety is small. In this review we discuss how herbal teas may be beneficial in some areas of clinical and preventative health, and what further research is required to understand whether regular consumption can contribute to healthy living more generally.


Assuntos
Medicina Tradicional , Compostos Fitoquímicos/análise , Plantas Medicinais , Chás de Ervas/análise , Biodiversidade , Humanos , Medicina Preventiva
17.
Food Chem Toxicol ; 130: 142-153, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31112705

RESUMO

In this study five types of herbal teas were used to quantify the effect of comminution of the leaves on resulting PA exposure. Results show that PA levels extracted from intact leaves were consistently lower than from comminuted tea leaves. The Margin of Exposure (MOE) approach was applied to evaluate the consequences of this difference for the associated risks in the scenario of lifetime exposure. Furthermore, we considered medicinal use of these teas for shorter-than-lifetime exposure scenarios, and also analysed the risks of shorter-than-lifetime use of eight herbal medicines and 19 previously analysed plant food supplements. This analysis revealed that shorter-than-lifetime use resulted in MOE values < 10,000 upon use for 40-3450 weeks during a lifetime, with for only a limited number of herbal teas and medicines use of two weeks a year (150 weeks during a 75 year lifetime) would still raise a concern. It is concluded that taking more realistic conditions into account markedly reduces the concerns raised for these herbal preparations. These results also illustrate the need for development of a generally accepted method for taking short term exposure into account in risk assessment of compounds that are genotoxic and carcinogenic.


Assuntos
Preparações de Plantas/química , Preparações de Plantas/toxicidade , Alcaloides de Pirrolizidina/toxicidade , Chás de Ervas/análise , Chás de Ervas/toxicidade , Carcinógenos , Humanos , Modelos Biológicos , Extratos Vegetais/química , Extratos Vegetais/toxicidade , Folhas de Planta/química , Plantas Medicinais/química , Alcaloides de Pirrolizidina/química , Fatores de Risco
18.
Food Funct ; 10(4): 2186-2197, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30942219

RESUMO

A new acidic polysaccharide (GPTP-3) with a molecular weight of 2.49 × 106 Da was extracted and purified from Gynostemma pentaphyllum tea. Monosaccharide analysis revealed that GPTP-3 mainly comprised mannose (20.4%), glucuronic acid (17.4%), glucose (33.4%), and galactose (21.4%) (parentheses indicate the molar percentages). Immunostimulating assays indicated that GPTP-3 could markedly promote the secretion of NO, TNF-α, IL-1ß, and IL-6 in murine macrophage RAW264.7. TLR4 was found to be a recognized target of GPTP-3. Moreover, TLR4-related mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/Akt, including ERK, JNK, p38, and Akt, were rapidly activated by GPTP-3 in RAW264.7 cells. Furthermore, GPTP-3 was found to induce the nuclear translocation of NF-κB subunit p65. All these findings suggest that MAPK, PI3K/Akt, and NF-κB pathways are involved in GPTP-3-induced macrophage activations, and GPTP-3 has the potential to be developed as a functional food with immunomodulatory functions.


Assuntos
Gynostemma/química , Fatores Imunológicos/farmacologia , Macrófagos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Polissacarídeos/farmacologia , Animais , Fatores Imunológicos/química , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/imunologia , NF-kappa B/genética , NF-kappa B/imunologia , Extratos Vegetais/química , Polissacarídeos/química , Células RAW 264.7 , Chás de Ervas/análise , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
19.
Food Addit Contam Part B Surveill ; 12(3): 199-208, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30961455

RESUMO

The occurrence of 12 mycotoxins has been analysed by liquid chromatography - time of flight mass spectrometry in the batch of 60 herbal teas purchased from drugstores in Latvia. Among the dry tea samples, 90% were positive for one to eight mycotoxins. Enniatin B and deoxynivalenol (DON) were the most frequently detected mycotoxins in 55% and 45% of the samples, respectively. DON reached the highest level, from 129 µg kg-1 in herbal blend to 5,463 µg kg-1 in wormwood tea. Ochratoxin A (OTA) and aflatoxin B1 (AFB1) were found in 10% and 20% of the samples at the concentrations ranged between 2.99-30.3 µg kg-1 and 3.40-23.7 µg kg-1. Studies of the tea infusion process indicated that 32-100% of DON and zearalenone present in dry teas were extracted into the infusions. Dietary exposure assessment was performed, using the determined mycotoxin levels and the available consumption data.


Assuntos
Contaminação de Alimentos , Micotoxinas/química , Chás de Ervas/análise , Cromatografia Líquida de Alta Pressão , Exposição Dietética , Análise de Alimentos , Humanos , Letônia , Reprodutibilidade dos Testes , Medição de Risco , Espectrometria de Massas em Tandem
20.
J Agric Food Chem ; 67(17): 4967-4975, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30955332

RESUMO

Rooibos tea ( Aspalathus linearis) is a well-known South African herbal tea enjoyed worldwide. Limited reports indicate the potential of rooibos tea to alter the activity of certain cytochrome P450 (CYP450) isozymes. In this study, the phytochemical investigation of MeOH extract of A. linearis (leaves and stems) resulted in the isolation and characterization of 11 phenolic compounds. The MeOH extract exhibited significant inhibition of the major human CYP450 isozymes (CYP3A4, CYP1A2, CYP2D6, CYP2C9, and CYP2C19). The strongest inhibition was observed by the extract for CYP3A4 (IC50 1.7 ± 0.1 µg/mL) followed by CYP2C19 (IC50 4.0 ± 0.3 µg/mL). Among the tested phytochemicals, the most potent inhibitors were isovitexin on CYP3A4 (IC50 3.4 ± 0.2 µM), vitexin on CYP2C9 (IC50 8.0 ± 0.2 µM), and thermopsoside on CYP2C19 (IC50 9.5 ± 0.2 µM). The two major, structurally related compounds aspalathin and nothofagin exhibited a moderate pregnane-X receptor (PXR) activation, which was associated with increased mRNA expression of CYP3A4 and CYP1A2, respectively. These results indicate that a high intake of nutraceuticals containing rooibos extracts may pose a risk of herb-drug interactions when consumed concomitantly with clinical drugs that are substrates of CYP enzymes.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Aspalathus/química , Sistema Enzimático do Citocromo P-450/química , Preparações de Plantas/química , Receptor de Pregnano X/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Aspalathus/metabolismo , Linhagem Celular , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Inocuidade dos Alimentos , Humanos , Folhas de Planta/química , Preparações de Plantas/metabolismo , Receptor de Pregnano X/genética , Receptor de Pregnano X/metabolismo , Chás de Ervas/análise
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