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Developing a novel and potent adjuvant with great biocompatibility for immune response augmentation is of great significance to enhance vaccine efficacy. In this work, we prepared a long-term stable, pH-sensitive, and biodegradable Mn3(PO4)2·3H2O nanoparticle (nano-MnP) by simply mixing MnCl2/NaH2PO4/Na2HPO4 solution for the first time and employed it as an immune stimulant in the bivalent COVID-19 protein vaccine comprised of wild-type S1 (S1-WT) and Omicron S1 (S1-Omicron) proteins as antigens to elicit a broad-spectrum immunity. The biological experiments indicated that the nano-MnP could effectively activate antigen-presenting cells through the cGAS-STING pathway. Compared with the conventional Alum-adjuvanted group, the nano-MnP-adjuvanted bivalent vaccine elicited approximately 7- and 8-fold increases in IgG antibody titers and antigen-specific IFN-γ secreting T cells, respectively. Importantly, antisera of the nano-MnP-adjuvanted group could effectively cross-neutralize the SARS-CoV-2 and its five variants of concern (VOCs) including Alpha, Beta, Gamma, Delta, and Omicron, demonstrating that this bivalent vaccine based on S1-WT and S1-Omicron proteins is an effective vaccine design strategy to induce broad-spectrum immune responses. Collectively, this nano-MnP material may provide a novel and efficient adjuvant platform for various prophylactic and therapeutic vaccines and provide insights for the development of the next-generation manganese adjuvant.
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BACKGROUND: A key challenge for unmanned aerial vehicle (UAV) spraying sometimes used in tea plantations is the downwash flow structure there stronger than in crops. In addition, the UAV spray is affected by the relationship between the nozzle design and the pesticide. However, there is little current research on this aspect. As a preliminary step this study focuses on the most appropriate pesticide for a designated nozzle in a six-rotor UAV according to the nozzle-pesticide relationship using a three-dimensional computational fluid dynamics model. This model considers the downwash flow structure effect and nozzle spray performance in hover. Nozzle FVP110-02, widely used in six-rotor UAVs, is used as a representative nozzle and bifenthrin and tea saponin water, commonly used in tea plantations, are used as the pesticides. RESULTS: The downwash flow structure of the six-rotor UAV in hover was conveniently controlled by the flight height and rotational speed, thereby causing the turbulence to be more stable. For nozzle FVP110-02, bifenthrin was more appropriate than tea saponin water at the same concentration, whilst bifenthrin and tea saponin water at a concentration of 1:1000 showed the best performance under identical working conditions. CONCLUSION: The numerical model developed here was shown to be effective for investigating the relationship between nozzle and pesticide. Our findings will help to not only improve UAV spraying for tea cultivation but also provide guidelines for pesticide selection in crops. Further work will address the comparison of the rigorous qualification of the numerical simulations with the measurements by the field test. © 2023 Society of Chemical Industry.
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Plaguicidas , Plaguicidas/análisis , Dispositivos Aéreos No Tripulados , Productos Agrícolas , TéRESUMEN
Geographic-label is a remarkable feature for Chinese tea products. In this study, the UHPLC-Q/TOF-MS-based metabolomics approach coupled with chemometrics was used to determine the five narrow-geographic origins of Keemun black tea. Thirty-nine differentiated compounds (VIP > 1) were identified, of which eight were quantified. Chemometric analysis revealed that the linear discriminant analysis (LDA) classification accuracy model is 91.7%, with 84.7% cross-validation accuracy. Three machine learning algorithms, namely feedforward neural network (FNN), random forest (RF) and support vector machine (SVM), were introduced to improve the recognition of narrow-geographic origins, the performances of the model were evaluated by confusion matrix, receiver operating characteristic curve (ROC) and area under the curve (AUC). The recognition of RF, SVM and FNN for Keemun black tea from five narrow-geographic origins were 87.5%, 94.44%, and 100%, respectively. Importantly, FNN exhibited an excellent classification effect with 100% accuracy. The results indicate that metabolomics fingerprints coupled with chemometrics can be used to authenticate the narrow-geographic origins of Keemun black teas.
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Camellia sinensis , Té , Algoritmos , Cromatografía Líquida de Alta Presión , Aprendizaje Automático , MetabolómicaRESUMEN
In traditional oral practice, the presystemic interactions with gut microbiota is an important mechanism underlying the holistic health benefits of Chinese herbal medicines (CHMs), making the study of CHMs distinct from the research of Western medicines of which the systemic exposure (level in blood) is the starting point and the core. Gut microbial metabolism complements host metabolism in maintaining metabolic homeostasis of many biologically important endogenous molecules and the disposition of numerous exogenous compounds. Among them, the widely distributed gut bacterial β-glucuronidases (BGUSs) coordinate with host UDP-glucuronosyltransferases (UGTs) to play a role in the occurrence and intervention of diseases by affecting the glucuronidation homeostasis and altering the intestinal local and/or systemic exposure of endogenous compounds and xenobiotics. On one hand, many ingredients of CHMs undergo enterohepatic circulation; On the other hand, CHMs can act on BGUSs directly or indirectly change the distribution and function of BGUSs through reprogramming gut microbiome. The multiple interactions between BGUSs and CHMs may play an important role in the overall therapeutic benefits of CHMs. This work firstly summarizes the latest research progress on BGUSs; then the physiological, pathological and pharmacological significance of BGUSs are exemplified with representative endogenous and exogenous compounds from the aspects of nutrient utilization, metabolic homeostasis, and therapeutic response based on the varied substrate spectra of BGUSs; finally, the scattered data in literature were integrated to summarize the multiple interactions between BGUSs and CHMs, highlighting the important role of BGUSs in the holistic actions of CHMs.
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BACKGROUND: Virtual reality (VR) training are regarded as promising new tools for rehabilitation, but the effect on patients' daily participation is controversial. This study aimed to evaluate the effect of virtual reality (VR) training on different types of patients' daily participation through a meta-analysis. METHODS: The PubMed, Cochrane central register of controlled trials, Embase, and web science databases were searched for studies published through September 2020. Thirty-five randomized controlled trials of virtual reality (VR) training compared with conventional treatment, Other electronic rehabilitation systems, usual care for various types of patients were included. All of the studies were available in English. Standardized mean differences (SMD), 95 % confidence intervals (CI), publication bias, and heterogeneity were calculated. RESULTS: The Virtual reality (VR) training group is better than the control group in daily participation improvement on all types of patients. There was a small, significant effect(pï¼0.001; SMD = 0.25[95 %CI,0.14 to 0.36], I2 = 0.00 %). Observing only the type of Stroke, the VR training group is still better than the control group in improving patients' daily participation (pï¼0.001, SMD = 0.24[95 %CI, 0.11 to 0.37], I2 = 0.00 %). Using the cumulative Meta-analysis method to observe the included literature according to the timeline, Using the cumulative Meta-analysis method to observe the included literature according to the timeline, and it has only achieved positive results since 2015 (Nam-YoNg Lee 2015, p = 0.048, SMD = 0.22[95 %CI,0.00 to 0.44]). The heterogeneity of the studies was not detected, but there is obvious publication bias. CONCLUSIONS: Because of controversy over obvious publication bias, we need to be cautious about the conclusion that VR is better than the control group in promoting the patient's daily participation.
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Rehabilitación de Accidente Cerebrovascular , Accidente Cerebrovascular , Realidad Virtual , Humanos , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
Tea is the one of the most popular non-alcoholic caffeinated beverages in the world. Tea is produced from the tea plant (Camellia sinensis (L.) O. Kuntze), which is known to accumulate fluoride. This article systematically analyzes the literature concerning fluoride absorption, transportation and fluoride tolerance mechanisms in tea plants. Fluoride bioavailability and exposure levels in tea infusions are also reviewed. The circulation of fluoride within the tea plantation ecosystems is in a positive equilibrium, with greater amounts of fluoride introduced to tea orchards than removed. Water extractable fluoride and magnesium chloride (MgCl2 ) extractable fluoride in plantation soil are the main sources of absorption by tea plant root via active trans-membrane transport and anion channels. Most fluoride is readily transported through the xylem as F- /F-Al complexes to leaf cell walls and vacuole. The findings indicate that tea plants employ cell wall accumulation, vacuole compartmentalization, and F-Al complexes to co-detoxify fluoride and aluminum, a possible tolerance mechanism through which tea tolerates higher levels of fluoride than most plants. Furthermore, dietary and endogenous factors influence fluoride bioavailability and should be considered when exposure levels of fluoride in commercially available dried tea leaves are interpreted. The relevant current challenges and future perspectives are also discussed. © 2020 Society of Chemical Industry.
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Camellia sinensis/química , Fluoruros/análisis , Fluoruros/metabolismo , Aluminio/análisis , Aluminio/metabolismo , Disponibilidad Biológica , Transporte Biológico , Camellia sinensis/metabolismo , Pared Celular/química , Pared Celular/metabolismo , Exposición Dietética/efectos adversos , Exposición Dietética/análisis , Humanos , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Medición de Riesgo , Suelo/química , Té/químicaRESUMEN
Tea plant (Camellia sinensis (L.) O. Kuntze) is known to accumulate high concentrations of fluoride (F) in its leaves; however, the underlying mechanism of F accumulation remains unclear. The main objective of this study was to investigate the homeostatic self-defense mechanisms of tea leaves to F supplementation (0, 5, 20, and 50 mgL-1) by metabolomics and ionomics. We identified a total of 96 up-regulated and 40 down-regulated metabolites in tea leaves treated with F. Of these different compounds, minor polypeptides, carbohydrates and amino acids played valuable roles in the F-tolerating mechanism of tea plant. After F treatments, the concentrations of sodium (Na), ferrum (Fe), manganese (Mn), and molybdenum (Mo) were significantly increased in tea leaves, whereas the aluminum (Al) was decreased. These findings suggest that the ionic balance and metabolites are attributable to the development of F tolerance, providing new insight into tea plant adaptation to F stress.
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Camellia sinensis/metabolismo , Fluoruros/toxicidad , Estrés Fisiológico , Camellia sinensis/efectos de los fármacos , Iones , Metaboloma , Hojas de la PlantaRESUMEN
BACKGROUND: Removing excessive naturally occurring fluoride from tea and/or infusions is difficult because the process has low efficiency and causes secondary pollution. In this study, a novel electrodialysis (ED) technology was developed. We examined the effect of crucial parameters (electrolyte concentration, operation voltage, ED duration and initial concentration of the tea infusion) on defluoridation performance using a highly efficient ion-exchange membrane with five-compartment cells. RESULTS: The most effective ED system results were obtained at an electrolyte concentration of 10 g kg-1 and operating voltage of 20 V. Moreover, the fluoride removal capacity (10.70-66.93%) was highly dependent on the ED duration (1-15 min) and initial concentration of the tea infusion (0.5-10 g kg-1 ). The longer the ED duration and the lower the initial concentration, the higher was the defluoridation performance. During ED, limited loss of the main inclusions (total polyphenols, catechins, caffeine and selected ions) was observed. Furthermore, the D201 anion resin-filled ED stack (0.5-5 g) and improvement of concentrate compartment electrolyte (≥5 times the dilute compartment electrolyte) in the ED system enhanced the defluoridation rate significantly. CONCLUSION: ED is a potentially effective method that can be used for defluoridation in the deep processing of tea products. © 2019 Society of Chemical Industry.
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Diálisis/métodos , Fluoruros/química , Manipulación de Alimentos/métodos , Té/química , Diálisis/instrumentación , Fluoruros/aislamiento & purificación , Manipulación de Alimentos/instrumentaciónRESUMEN
BACKGROUND: Confirmation of food labeling that claims production in a small geographic region is critical to traceability, quality control and brand protection. In the current study, isotope ratio mass spectrometry (IRMS) was used to generate profiles of δ13 C and δ15 N to determine if the stable isotope signatures of Keemun black tea differ within the three counties that claim production. Other factors (cultivar type, leaf maturity and manufacturing process) were considered for their potential effects. RESULTS: Both cultivar type and leaf maturity have remarkable impact on the δ15 N values of tea leaves, and that the cultivar influenced the δ13 C values. Keemun black tea from Qimen county could be easily discriminated from samples from Dongzhi and Guichi counties based on δ15 N signatures. The k-NN model was cross-validated with an accuracy of 91.6%. Environmental factors and/or genotype seem to be the major reasons for δ15 N differences in Keemun black tea from the selected regions. CONCLUSION: This article provides a potential effective method to delineate the geographic point-of-origin of Keemun black tea based on δ15 N signatures. © 2018 Society of Chemical Industry.
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Camellia sinensis/química , Espectrometría de Masas/métodos , Isótopos de Nitrógeno/análisis , Té/química , Isótopos de Carbono/análisis , Análisis DiscriminanteRESUMEN
OBJECTIVE: To evaluate the immediate effect of moxibustion at Shenshu (BL 23) on renal hemodynamics in patients with chronic kidney disease(CKD)ï¼. METHODS: Thirty-two non-dialysis patients with CKD were recruited in this study. Moxibustion was applied at bilateral BL 23 for 30 min. The peak systolic velocity (PSV), end diastolic velocity (EDV) of the interlobar renal artery were measured by Doppler ultrasonography (US) before, and 0 and 15 min after moxibustion. The renal resistance index (RI) was equal to (PSVï¼EDV)/PSV. The body temperature (T), systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) were also monitored at the same time points. RESULTS: After moxibustion, the EVD level at 15 min after moxibustion was significantly increased (P<0.05), and the renal RI levels at 0 and 15 min after moxibustion were significantly down-regulated in comparison with their own pre-treatment (P<0.01). No significant changes were found in the levels of PSV, T, SBP, DBP and HR after moxibustion (P>0.05). CONCLUSION: Moxibustion at BL 23 can increase EDV and reduce renal RI of the interlobar renal artery in patients with CKD, which may be useful in relieving kidney disorders by improving renal blood flow.
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Moxibustión , Insuficiencia Renal Crónica , Velocidad del Flujo Sanguíneo , Presión Sanguínea , Hemodinámica , Humanos , RiñónRESUMEN
Environmental and plant factors (soil condition, variety, season, and maturity) and exposure risks of aluminum (Al), manganese (Mn), lead (Pb), cadmium (Cd), and copper (Cu) in tea leaves were investigated. The concentrations of these metals in tea leaves could not be predicted by their total concentrations in the soil. During any one season, there were differences in Al, Mn, and Cd levels between tea varieties. Seasonally, autumn tea and/or summer tea had far higher levels of Al, Mn, Pb, and Cd than did spring tea. Tea leaf maturity positively correlated with the concentrations of Al, Mn, Pb, and Cd, but negatively with Cu. The calculated average daily intake doses (mg/ [kgâ¢d]) for these metal elements were 0.14 (Al), 0.11 (Mn), 2.70 × 10-3 (Cu), 2.80 × 10-4 (Pb), and 2.88 × 10-6 (Cd). The hazard quotient values of each metal were all significantly lower than risk level (=1), suggesting that, for the general population, consumption of tea does not result in the intake of excessive amounts of Al, Mn, Pb, Cd, or Cu. This study identified the factors that can be monitored in the field to decrease consumer exposure to Al and Mn through tea consumption. PRACTICAL APPLICATION: Environmental and plant factors influence aluminum and heavy metal accumulation in tea leaves. Consumers of tea are not ingesting excessive Al, Mn, Pb, Cd, or Cu. Trackable factors were identified to manage exposure levels.
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Aluminio/análisis , Seguridad de Productos para el Consumidor , Exposición a Riesgos Ambientales/análisis , Metales Pesados/análisis , Hojas de la Planta/química , Té/química , China , Contaminación de Alimentos/análisis , Política Nutricional , Medición de Riesgo , Factores de Riesgo , Estaciones del Año , Contaminantes del Suelo/análisisRESUMEN
Two new oleanane-type saponins, named oleiferasaponins C4 (1) and C5 (2), were isolated from Camellia oleifera Abel. seed cake residue. Their respective structures were identified as 16α-hydroxy-22α-O-angeloyl-23α-aldehyde-28-dihydroxymethylene-olean-12-ene-3ß-O-[ß-d-galacto-pyranosyl-(1â2)]-[ß-d-glucopyranosyl-(1â2)-ß-d-galactopyranosy-(1â3)]-ß-d-glucopyranosid-uronic acid methyl ester (1) and 16α-hydroxy-22α-O-angeloyl-23α-aldehyde-28-dihydroxy-methylene-olean-12-ene-3ß-O-[ß-d-galactopyranosyl-(1â2)]-[ß-d-galactopyranosyl-(1â3)]-ß-d-glucopyranosiduronic acid methyl ester (2) through 1D- and 2D-NMR, HR-ESI-MS, and GC-MS spectroscopic methods. The two compounds exhibited potent cytotoxic activities against five human tumor cell lines (BEL-7402, BGC-823, MCF-7, HL-60 and KB).
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Antineoplásicos Fitogénicos/química , Camellia/química , Ácido Oleanólico/análogos & derivados , Extractos Vegetales/química , Saponinas/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Concentración 50 Inhibidora , Conformación Molecular , Ácido Oleanólico/química , Ácido Oleanólico/aislamiento & purificación , Ácido Oleanólico/farmacología , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Saponinas/aislamiento & purificación , Saponinas/farmacologíaRESUMEN
The aim of this study was to determine the levels of fluoride in commercial teas and to estimate the contribution of tea consumption to the fluoride recommended daily allowance. A total of 558 tea products in 6 categories, green tea, black tea, oolong tea, pu'er tea, white tea, and reprocessed tea, were collected in the period from 2010 to 2013. The levels of fluoride in infusions of these teas were determined by a fluoride-ion selective electrode. The mean fluoride level in all of the tea samples was 85.16 mg/kg. For each category of tea, the mean fluoride levels were 63.04, 99.74, 52.19, 101.67, 159.78, and 110.54 mg/kg for green tea, black tea, white tea, pu'er tea, oolong tea, and reprocessed tea, respectively. The fluoride content of tea from 4 tea zones in descending order were Southern tea zone (111.39 mg/kg) > Southwest tea zone (78.78 mg/kg) > Jiangnan tea zone (71.73 mg/kg) > Jiangbei tea zone (64.63 mg/kg). These areas produced teas with lower fluoride levels than available foreign-produced tea (161.11 mg/kg). The mean chronic daily intake (CDI) was 0.02 mg/(kgâ¢day) or 1.27 mg/kg. Generally, consuming tea from these 6 categories does not result in the intake of excessive amounts of fluoride for the general population.
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Camellia sinensis/química , Dieta , Conducta Alimentaria , Fluoruros/análisis , Té/química , Fluoruros/administración & dosificación , HumanosRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Traditional and local medicinal knowledge would be useful for finding pharmaceutical resources. Ethnopharmacological methods, especially quantitative analysis could help us to pre-screen herbs in field studies. "Using different plants as the same herb" is common in both traditional and local medicinal systems in China. In terms of medicine safety, it is not best choice, for it would lead to difficulty in controlling the quality, safety and efficacy of herbs. However, from the perspective of finding new resources for pharmaceutical industry, it would be beneficial. The usage of Huang-lian is one of the typical examples of "using different plants as the same herb". According to the previous Phytochemical and Pharmacological studies, berberine is the common effective compound of most of the species used as Huang-lian. Recently, berberine and other effective compounds of Huang-lian have gained much more attention and will become more popular in both medicinal researches and pharmaceutical industry. In our preliminary field work, we found that dozens of plant species might be used as Huang-lian by local people in Northwest Yunnan, an area well known by its rich biodiversity and culture diversity. These herbs might have potential value for pharmaceutical industry, for example, it could be used as the new resources to extract berberine and other effective compounds. Due to this, it is very necessary to collect, identify, document, and analyze the herbs used as Huang-lian in NW Yunnan. In the present study, we focused on that how to use traditional and local medicinal knowledge to find resources for pharmaceutical industry. MATERIAL AND METHODS: In the field work, interviews and participative observation were used. In the quantitative analysis of the local knowledge, Informant consensus factor (Fic), Use value (UV) and Relative frequency of citation (RFC) were used. RESULTS AND DISCUSSION: A total of 230 key informants were interviewed and 29 plant species belonging to 8 families and 11 genera used as Huang-lian were collected in the study area. Diarrhoea had the highest value of Fic.xiana had the highest value of UV and RFC. The main effective compounds of most of these species were related to the protoberberine group of isoquinoline alkaloids, e.g. berberine, jatrorrhizin and palmatine, according to the previous phytochemical studies. CONCLUSION: The range of sources of Huang-lian were very wide in NW Yunnan. Treating diarrhoea was the most common use of these species, most of which contained berberine. Based on the results of quantitative analysis, M. duclouxiana may had the greatest potential to future uses, e.g. as a resource for pharmaceutical industry. In the present study, we did not discuss whether the herbs used as Huang-lian could replace the standard Huang-lian in traditional or local medicine or not, and we just wanted to explore how this phenomenon could be used to find new resources for pharmaceutical industry.
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Medicina Tradicional/métodos , Fitoterapia/métodos , Preparaciones de Plantas/uso terapéutico , China , Etnofarmacología , Humanos , Encuestas y CuestionariosRESUMEN
Albino tea has received increased attention due to its brisk flavour. To identify changes in the key chemical constituents conveying important qualities to albino tea, the metabolite profiles of four albino cultivars and one green tea cultivar were analysed. Compared to the green tea control, significantly decreased contents of chlorophyll (Chl) (p<0.01), total carotenoids (p<0.05), caffeine (p<0.01), and total catechins (p<0.05) were found in albino tea leaves with a few exceptions, whereas increases were noted in the Chl a/b ratio and the contents of both zeaxanthin and free amino acids, including theanine. Multivariate analysis identified catechins and carotenoids as the most important contributors to the metabolic profile variance between the albino and green tea cultivars. High levels of amino acids, along with low levels of chlorophylls, catechins and caffeine, contribute to the qualities of albino tea, which include reduced astringency and bitterness, along with a strong umami taste.
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Camellia sinensis/química , Extractos Vegetales/análisis , Hojas de la Planta/química , Aminoácidos/análisis , Aminoácidos/metabolismo , Cafeína/análisis , Cafeína/metabolismo , Camellia sinensis/clasificación , Camellia sinensis/crecimiento & desarrollo , Camellia sinensis/metabolismo , Catequina/análisis , Catequina/metabolismo , Clorofila/análisis , Clorofila/metabolismo , Clorofila A , Análisis Discriminante , Humanos , Extractos Vegetales/metabolismo , Hojas de la Planta/clasificación , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/metabolismo , Control de Calidad , Gusto , Té/química , Xantófilas/análisis , Xantófilas/metabolismo , ZeaxantinasRESUMEN
Sample preparation using an absorbent for removal of polyphenols and a solid-phase extraction (SPE) cartridge for cleanup followed by high-performance liquid chromatography (HPLC) has been investigated for the simultaneous determination of eight neonicotinoid insecticides (dinotefuran, nitenpyram, thiamethoxam, imidacloprid, clothianidin, imidaclothiz, acetamiprid, and thiacloprid). After tea samples were soaked with water and extracted with acetonitrile, sample extracts were treated with an appropriate amount of polyvinylpolypyrrolidone (PVPP) to effectively remove polyphenols. The treated extract was cleaned up with a Carb-PSA cartridge. Neonicotinoid insecticides were eluted with acetonitrile from the cartridge and dried. The extract was redissolved with methanol/water (1:9, v/v) and analyzed by conventional HPLC coupled with an ultraviolet detector. The recoveries of eight neonicotinoid insecticides in tea samples were 71.4-106.6% at 0.1-1.0 mg kg(-1) spiked levels. Relative standard deviations were <10% for all of the recovery tests. The established method was simple, effective, and accurate and could be used for monitoring neonicotinoid insecticides in tea.
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Camellia sinensis/química , Insecticidas/aislamiento & purificación , Residuos de Plaguicidas/aislamiento & purificación , Extracción en Fase Sólida/métodos , Té/química , Cromatografía Líquida de Alta Presión , Insecticidas/análisis , Residuos de Plaguicidas/análisisRESUMEN
The dissipation behaviour of three neonicotinoids - thiamethoxam, imidacloprid and acetamiprid - was compared in tea shoots, in Chinese green and black tea, and after tea infusion in hot water. The simple and rapid analytical procedures for the quantification of these three residues in these matrices were developed using HPLC with ultraviolet (UV) detection. Degradation rates in tea shoots of neonicotinoids applied in either recommended or double dosages followed first-order kinetics, with half-lives of 1.62 or 1.58 days for thiamethoxam, of 2.45 or 2.67 days for imidacloprid, and of 3.24 or 3.85 days for acetamiprid, respectively. Through harvest and processing the residue retentions for thiamethoxam, imidacloprid and acetamiprid were 85.0%, 84.1% and 70.6% of the initial dosages in green tea, and 77.1%, 52.4% and 57.4% in black tea. These three residues all showed high transfer rates through green or black tea brewing of 80.5% or 81.6% for thiamethoxam, of 63.1% or 62.2% for imidacloprid, and of 78.3% or 80.6% for acetamiprid. Waiting periods between the last application and harvest of at least 12, 17 and 20 days were suggested for thiamethoxam, imidacloprid and acetamiprid, respectively, after application at their recommend dosages to ensure levels below a maximum residue limit (MRL) of 0.05 mg kg(-1).
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Contaminación de Alimentos/análisis , Insecticidas/análisis , Té/química , Camellia sinensis/efectos adversos , Camellia sinensis/química , China , Manipulación de Alimentos , Humanos , Imidazoles/efectos adversos , Imidazoles/análisis , Insecticidas/efectos adversos , Neonicotinoides , Nitrocompuestos/efectos adversos , Nitrocompuestos/análisis , Oxazinas/efectos adversos , Oxazinas/análisis , Residuos de Plaguicidas/efectos adversos , Residuos de Plaguicidas/análisis , Piridinas/efectos adversos , Piridinas/análisis , Té/efectos adversos , Tiametoxam , Tiazoles/efectos adversos , Tiazoles/análisisRESUMEN
Pot experiments and the sequential extraction method were conducted to study the chemical form changes of exogenous water solution fluoride in tea garden soil and their contribution to fluoride accumulation of tea plant. The results showed that the background concentration of all chemical forms of fluoride had little changes with time treatment, which was in a relatively stable state. The exogenous water solution fluoride adding to the soils was rapidly transformed to other fractions. Under the 10 mg x kg(-1) fluoride treatment, the concentration of water solution fluoride increased firstly and then decreased with time treatment, the concentration of organic matter fluoride and Fe/Mn oxides fluoride decreased, the concentration of exchangeable fluoride was not different before and after the treatment (P > 0.05), and the concentration of residual fluoride was in a relatively stable state; under the 200 mg x kg(-1) fluoride treatment, the concentration of water solution fluoride, Fe/Mn oxides fluoride and organic matter fluoride decreased with time treatment, the concentration of exchangeable fluoride increased firstly and then decreased, showed no difference before and after the treatment (P > 0.05), and the concentration of residual fluoride increased, with some differences compared with 10 mg x kg(-1) fluoride treatment. The concentration of total fluoride in root, stem and leaf had significant differences under 0-10 mg x kg(-1) fluoride treatment (P < 0.05), while showed no difference from 10 to 100 mg x kg(-1) fluoride treatment (P > 0.05). Step regression analysis suggested the contribution of all chemical forms of fluoride to the concentration of water solution fluoride and total fluoride of root, stem and leaf had some differences, there was a remarkable regression relationship among the content of total fluoride in leaf and water solution fluoride, organic matter fluoride, Fe/Mn oxides fluoride and residual fluoride in soil, however, no significant difference for water solution fluoride of leaf was found.
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Fluoruros/análisis , Contaminantes del Suelo/análisis , Suelo/química , Disponibilidad Biológica , Camellia sinensis , Soluciones , AguaRESUMEN
AIMS@#To investigate the antitumor effects of extracts from Oxytropis falcata on human hepatocellular carcinoma SMMC-7721 cells in vitro and in transplanted murine H22 tumors in vivo.@*METHODS@#Cell proliferation, cell cycle distribution and apoptosis in SMMC-7721 cells were determined and tumor growth inhibition in H22 tumors was investigated. Cell cycle distribution was analyzed by flow cytometry with propidium iodide (PI) and Annexin V-FITC/ PI double staining.@*RESULTS@#MTT assay revealed that essential oil and flavonoids of O. falcata (named EOOF and FOF) inhibited proliferation of SMMC-7721 cells in a dose-dependent manner. The IC50 value of EOOF and FOF were 0.115 and 0.097 mg·mL(-1), respectively. Cell cycle was arrested at G(1) phase, and induction of apoptosis occurred in SMMC-7721 cells when subjected to FOF. Growth inhibition in H22 solid tumors transplanted mice was significantly pronounced after being treated with FOF, and the inhibition ratio were 56.1% and 70.8% at the concentration of 30 and 60 mg·kg(-1).@*CONCLUSION@#The results suggest that FOF promotes apoptosis in SMMC-7721 cells and inhibits H22 tumor growth, resulting in a potential antitumor effect on hepatic cancer.
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Animales , Humanos , Masculino , Ratones , Antineoplásicos Fitogénicos , Apoptosis , Carcinoma Hepatocelular , Quimioterapia , Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Medicamentos Herbarios Chinos , Inhibidores de Crecimiento , Neoplasias Hepáticas , Quimioterapia , Ratones Endogámicos ICR , Oxytropis , QuímicaRESUMEN
Traditional or folk medicine, a multi-discipline subject, has gained much attention from all over the world at present. Based on the previous literatures, the overview on the recent advance of folk medicine used by Hakka was summarized. The key questions of folk medicine used by Hakka were also highlighted. It could be considered as a very important part of traditional Chinese medicines.