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1.
Hepatology ; 75(4): 968-982, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34662439

RESUMO

BACKGROUND AND AIMS: Lipoprotein Z (LP-Z) is an abnormal free cholesterol (FC)-enriched LDL-like particle discovered from patients with cholestatic liver disease. This study aims to define the diagnostic value of LP-Z in alcohol-associated hepatitis (AH) and interrogate the biology behind its formation. APPROACH AND RESULTS: We measured serum levels of LP-Z using nuclear magnetic resonance spectroscopy, a well-established clinical assay. Serum levels of LP-Z were significantly elevated in four AH cohorts compared with control groups, including heavy drinkers and patients with cirrhosis. We defined a Z-index, calculated by the ratio of LP-Z to total apolipoprotein B-containing lipoproteins, representing the degree of deviation from normal VLDL metabolism. A high Z-index was associated with 90-day mortality independent from the Model for End-Stage Liver Disease (MELD) and provided added prognosticative value. Both a Z-index ≤ 0.6 and a decline of Z-index by ≥0.1 in 2 weeks predicted 90-day survival. RNA-sequencing analyses of liver tissues demonstrated an inverse association in the expression of enzymes responsible for the extrahepatic conversion of VLDL to LDL and AH disease severity, which was further confirmed by the measurement of serum enzyme activity. To evaluate whether the FC in LP-Z could contribute to the pathogenesis of AH, we found significantly altered FC levels in liver explant of patients with AH. Furthermore, FC in reconstituted LP-Z particles caused direct toxicity to human hepatocytes in a concentration-dependent manner, supporting a pathogenic role of FC in LP-Z. CONCLUSIONS: Impaired lipoprotein metabolism in AH leads to the accumulation of LP-Z in the circulation, which is hepatotoxic from excessive FC. A Z-index ≤ 0.6 predicts 90-day survival independent from conventional biomarkers for disease prognostication.


Assuntos
Doença Hepática Terminal , Hepatite Alcoólica , Apolipoproteínas B , Colesterol , Humanos , Lipoproteína(a) , Lipoproteínas , Índice de Gravidade de Doença
2.
Ecotoxicol Environ Saf ; 266: 115568, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37832482

RESUMO

The tea plant accumulates elevated levels of fluoride (F) from environmental sources. Drinking tea containing high F levels poses a potential threat to human health. Selenium (Se) was applied by foliar spray to investigate its effects on F accumulation and physiology in tea plant. Foliar application of different forms of Se, i.e., Na2SeO3, Kappa-selenocarrageenan, Selenomethionine and Nanoselenium, reduced F content in tea leaves by 10.17 %-44.28 %, 16.12 %-35.41 %, 22.19 %-45.99 % and 22.24 %-43.82 %, respectively. Foliar spraying Se could increase F accumulation in pectin through increasing pectin content and pectin demethylesterification to bind more F in the cell wall, which decreased the proportion of water-soluble fluoride in tea leaves. Application of Se significantly decreased the contents of chromium (39.6 %-72.0 %), cadmium (48.3 %-84.4 %), lead (2.2 %-44.4 %) and copper (14.1 %-44.6 %) in tea leaves. Foliar spraying various forms of Se dramatically increased the Se content and was efficiently transformed into organic Se accounting for more than 80 % in tea leaves. All Se compounds increased peroxidase activity by 3.3 %-35.5 % and catalase activity by 2.6 %-99.4 %, reduced malondialdehyde content by 5.6 %-37.1 %, and increased the contents of chlorophyll by 0.65 %-31.8 %, carotenoids by 0.24 %-27.1 %, total catechins by 1.6 %-21.0 %, EGCG by 4.4 %-17.6 % and caffeine by 9.1 %-28.6 %. These results indicated that Se application could be served as a potential efficient and safe strategy diminishing the concentration of F in tea leaves.


Assuntos
Camellia sinensis , Selênio , Humanos , Selênio/metabolismo , Fluoretos/análise , Antioxidantes/metabolismo , Camellia sinensis/química , Folhas de Planta/metabolismo , Chá , Pectinas/metabolismo
3.
J Sci Food Agric ; 102(13): 6123-6130, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35474316

RESUMO

BACKGROUND: Most studies focus on the geographically larger production areas in tea traceability. However, famous high-quality tea is often produced in a narrow range of origins, which makes traceability a challenge. In this study, Taiping Houkui (TPHK) green tea of narrow geographical origin was rapidly identified using Fourier-transform near-infrared (FT-NIR) spectroscopy. RESULTS: First, spectral information of 114 TPHK samples from four production areas was acquired. Second, the synthetic minority over-sampling technique (SMOTE) was used to balance the sample data set, and three different spectral pre-processing methods were compared. Third, three feature variable selection algorithms were used to obtain the pre-processed spectral features. Finally, extreme learning machine (ELM) models based on the variables obtained from the selected features were established to trace the TPHK origin. The optimized ELM model achieves 95.35% classification accuracy in the test set. CONCLUSION: The present study demonstrates that the optimized variable selection method in combination with NIR spectroscopy represents a suitable strategy for tea traceability in narrow regions. © 2022 Society of Chemical Industry.


Assuntos
Espectroscopia de Luz Próxima ao Infravermelho , Chá , Algoritmos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Chá/química
4.
Ecotoxicol Environ Saf ; 209: 111732, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33373928

RESUMO

Fluoride, widely presented in drinking water and tea, may be detrimental or beneficial to the human health, depending on its dosages ingested. However, the relationship of different dosages of fluoride and gut microbiota is still unclear. In this work, the fermentation model using fecal samples provided by four volunteers was used to evaluate the effects of different dosages of fluoride (1, 2, 10 and 15 mg/L) on the gut microbiota in vitro. The result showed low dosages of fluoride (1 and 2 mg/L) had limited effect on the structure and functional Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway of gut microbiota. Furthermore, the low dosage of fluoride could promote the growth of beneficial gut microbiota, including Faecalibacterium and Lactobacillus. Whereas, the high dosage of fluoride (10 and 15 mg/L) significantly changed the composition and functional KEGG pathway of gut microbiota. Moreover, the high dosage of fluoride could also reduce the beneficial gut microbiota, including Faecalibacterium and Phascolarctobacterium, and increase the harmful bacterium including Proteobacteria and Enterobacteriaceae. Both low and high dosages of fluoride showed limited effect on the productions of short-chain fatty acids (SCFAs). Thus, the beneficial or detrimental fluoride to gut microbiota depends on its dosages. The fluoride is expected to serve as a food additive in suitable dosage to improve human health through modulation of the gut microbiota. Moreover, more attention should be paid to toxicity of fluoride with high dosage to gut microbiota.


Assuntos
Fluoretos/toxicidade , Microbioma Gastrointestinal/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Bactérias/metabolismo , Ácidos Graxos Voláteis/análise , Ácidos Graxos Voláteis/química , Ácidos Graxos Voláteis/metabolismo , Fezes/química , Fermentação , Fluoretos/análise , Humanos , Lactobacillus/metabolismo
5.
J Sci Food Agric ; 101(2): 379-387, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32623727

RESUMO

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.


Assuntos
Camellia sinensis/química , Fluoretos/análise , Fluoretos/metabolismo , Alumínio/análise , Alumínio/metabolismo , Disponibilidade Biológica , Transporte Biológico , Camellia sinensis/metabolismo , Parede Celular/química , Parede Celular/metabolismo , Exposição Dietética/efeitos adversos , Exposição Dietética/análise , Humanos , Folhas de Planta/química , Folhas de Planta/metabolismo , Medição de Risco , Solo/química , Chá/química
6.
J Sci Food Agric ; 100(1): 168-176, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31471909

RESUMO

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.


Assuntos
Diálise/métodos , Fluoretos/química , Manipulação de Alimentos/métodos , Chá/química , Diálise/instrumentação , Fluoretos/isolamento & purificação , Manipulação de Alimentos/instrumentação
7.
J Sci Food Agric ; 100(8): 3554-3559, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32124449

RESUMO

BACKGROUND: Tea (Camellia sinensis (L.) O. Kuntze) is a hyper-accumulator of fluoride (F). To understand F uptake and distribution in living plants, we visually evaluated the real-time transport of F absorbed by roots and leaves using a positron-emitting (18 F) fluoride tracer and a positron-emitting tracer imaging system. RESULTS: F arrived at an aerial plant part about 1.5 h after absorption by roots, suggesting that tea roots had a retention effect on F, and then was transported upward mainly via the xylem and little via the phloem along the tea stem, but no F was observed in the leaves within the initial 8 h. F absorbed via a cut petiole (leaf 4) was mainly transported downward along the stem within the initial 2 h. Although F was first detected in the top and ipsilateral leaves, it was not detected in tea roots by the end of the monitoring. During the monitoring time, F principally accumulated in the node. CONCLUSION: F uptake by the petiole of excised leaf and root system was realized in different ways. The nodes indicated that they may play pivotal roles in the transport of F in tea plants. © 2020 Society of Chemical Industry.


Assuntos
Camellia sinensis/metabolismo , Fluoretos/metabolismo , Transporte Biológico , Camellia sinensis/química , Fluoretos/análise , Floema/química , Floema/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Xilema/química , Xilema/metabolismo
8.
Molecules ; 24(24)2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31835551

RESUMO

Chemical pesticides are commonly used during the cultivation of agricultural products to control pests and diseases. Excessive use of traditional pesticides can cause environmental and human health risks. There are ongoing searches for new plant-derived pesticides to reduce the use of chemical pesticides. In this study, tea saponin extracts of different purities were extracted from Camellia oleifera seeds using AB-8 macroporous resin and gradient elution with ethanol. The insecticidal effects of the tea saponin extracts were evaluated by contact toxicity tests and stomach toxicity tests using the lepidopteran pest of tea plantation, Ectropis obliqua. The total saponins extracted using 70% ethanol showed strong contact toxicity (LC50 = 8.459 mg/L) and stomach toxicity (LC50 = 22.395 mg/L). In-depth mechanistic studies demonstrated that tea saponins can disrupt the waxy layer of the epidermis, causing serious loss of water, and can penetrate the inside of the intestine of E. obliqua. After consumption of the tea saponins, the intestinal villi were shortened and the cavities of the intestinal wall were disrupted, which resulted in larval death. This study highlights the potential of tea saponins as a natural, plant-derived pesticide for the management of plant pests.


Assuntos
Camellia/química , Inseticidas/química , Inseticidas/farmacologia , Saponinas/química , Animais , Fenômenos Químicos , Insetos/efeitos dos fármacos , Inseticidas/isolamento & purificação , Dose Letal Mediana , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Solubilidade , Testes de Toxicidade
9.
J Sci Food Agric ; 99(5): 2596-2601, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30411367

RESUMO

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.


Assuntos
Camellia sinensis/química , Espectrometria de Massas/métodos , Isótopos de Nitrogênio/análise , Chá/química , Isótopos de Carbono/análise , Análise Discriminante
10.
J Sci Food Agric ; 97(5): 1509-1516, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27404035

RESUMO

BACKGROUND: Brick tea usually contains very high fluoride, which may affect human health. Biosorbents have received much attention for selective removal of fluoride because of low cost, environmental friendliness, and relative safeness. RESULTS: In the present study, a highly selective fluoride tea waste based biosorbent, namely, aluminum (Al) oxide decorated tea waste (Tea-Al), was successfully prepared. The Tea-Al biosorbent was characterized by energy-dispersive spectrometry, Fourier transform infrared spectroscopy, powder X-ray diffraction and X-ray photoelectron spectroscopic analysis. The Tea-Al sample exhibited remarkably selective adsorption for fluoride (52.90%), but a weaker adsorption for other major constituents of brick tea infusion, such as catechins, polyphenols and caffeine, under the same conditions. Fluoride adsorption by Tea-Al for different times obeyed the surface reaction and adsorption isotherms fit the Freundlich model. In addition, the fluoride adsorption mechanism appeared to be an ion exchange between hydroxyl and fluoride ions. CONCLUSION: Results from this study demonstrated that Tea-Al is a promising biosorbent useful for the removal of fluoride in brick tea infusion. © 2016 Society of Chemical Industry.


Assuntos
Óxido de Alumínio/química , Camellia sinensis/química , Fluoretos/química , Chá/química , Adsorção , Contaminação de Alimentos/prevenção & controle
11.
Ecotoxicol Environ Saf ; 131: 14-21, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27162130

RESUMO

This study investigated the fluoride present in tea plants (Camellia sinensis (L.) O. Kuntze) and its relationship to soils, varieties, seasons and tea leaf maturity. The study also explored how different manufacturing processes affect the leaching of fluoride into tea beverages. The fluoride concentration in the tea leaves was significantly correlate to the concentration of water-soluble fluoride in the soil. Different tea varieties accumulated different levels of fluoride, with varieties, Anji baicha having the highest and Nongkang zao having the lowest fluoride concentration. In eight different varieties of tea plant harvested over three tea seasons, fluoride concentration were highest in the summer and lowest in the spring in china. The fluoride concentration in tea leaves was directly related to the maturity of the tea leaves at harvest. Importantly, the tea manufacturing process did not introduced fluoride contamination. The leaching of fluoride was 6.8% and 14.1% higher in black and white tea, respectively, than in fresh tea leaves. The manufacturing step most affecting the leaching of fluoride into tea beverage was withering used in white, black and oolong tea rather than rolling or fermentation. The exposure and associated health risks for fluoride concentration in infusions of 115 commercially available teas from Chinese tea markets was determined. The fluoride concentration ranged from 5.0 to 306.0mgkg(-1), with an average of 81.7mgkg(-1). The hazard quotient (HQ) of these teas indicated that there was no risk of fluorosis from drinking tea, based on statistical analysis by Monte Carlo simulation.


Assuntos
Camellia sinensis/química , Fluoretos/análise , Folhas de Planta/química , Chá/química , Camellia sinensis/crescimento & desenvolvimento , China , Manipulação de Alimentos , Humanos , Método de Monte Carlo , Medição de Risco , Estações do Ano , Solo/química , Chá/efeitos adversos
12.
Cell Div ; 19(1): 12, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38610003

RESUMO

BACKGROUND: Exploring novel biomarkers for gastric cancer holds promise for enhancing patients' therapy and survival rates. lncRNAs and miRNAs have emerged as important biomarkers for various human cancers. However, the role of lncRNA RMST (RMST) in gastric cancer development and the mechanism underlying its function remains unclear. RESULTS: Significant upregulation of RMST was observed in gastric cancer tumor tissues. RMST levels showed strong correlation with patients' lymph node metastasis and TNM stage and serving as a predictor of adverse prognosis RMST negatively regulated miR-204-5p, which in turn mediated the inhibitory effects of RMST knockdown on gastric cancer cell growth and metastasis. CONCLUSION: RMST served as both a prognostic biomarker and tumor promoter by modulating miR-204-5p. Inhibiting RMST could represent a novel and potential therapeutic strategy for gastric cancer.

13.
Int J Biol Macromol ; 259(Pt 1): 129247, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199530

RESUMO

The molecular motion of starch at different glycerol concentrations (0, 20, 50, and 80 %) was investigated using Electron Paramagnetic Resonance (EPR) spectroscopy. Fourier-transform infrared (FTIR) spectroscopy and 1H nuclear magnetic resonance (1H NMR) spectroscopy confirmed that hydroxyl groups at the C2 and C3 positions of glucose units in corn starch (CS), waxy corn starch (WCS), and high amylose corn starch (HCS) were labeled with 4-amino-TEMPO. The crystallinities of CS, WCS, and HCS after spin-labeling decreased from 30.68 % to 3.21 %, 39.36 % to 1.65 %, and 28.54 % to 8.08 %, respectively. The pseudoplastic fluid properties of the spin-labeled starch remained shear-thin at different glycerol concentrations. EPR revealed the fast- and slow-motion components of the spin-labeled starch molecules dispersed in water. At a glycerol concentration of 20 %, the slow-motion component disappeared, indicating a faster rotational motion of the starch chain segments. As the glycerol concentration increased to 50 and 80 %, the rotational motion slowed because of high viscosity. In particular, the mobility of the spin-labeled WCS chains increased owing to easier access of glycerol and water to the branched structure. This study directly observed the dynamics of the molecular behavior of starch in glycerol-water systems.


Assuntos
Glicerol , Amido , Amido/química , Água , Espectroscopia de Ressonância de Spin Eletrônica/métodos , Amilose/química , Marcadores de Spin , Amilopectina
14.
Carbohydr Polym ; 339: 122239, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38823909

RESUMO

A new zirconium and cerium-modified polyvinyl alcohol (PVA) sodium carboxymethyl cellulose (NaCMC) film (PVA/CMC-Zr-Ce) was synthesized thru a high-speed shear-assisted method and its adsorption for the removal of fluoride was studied, in which the NaCMC provided -COONa for ion exchange between Na and Zr-Ce, thus the loading amount of Zr-Ce on films was accordingly increased. The morphology and structure of PVA/CMC-Zr-Ce were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). Besides, the mechanical properties, water contact angle, and swelling ratio of film were also evaluated. The addition of high-speed shear improved the dispersion of the emulsion system, and PVA/CMC-Zr-Ce film with good adsorption performance and film stability was prepared. While, it was found that the adsorption capacity could reach 67.25 mg/g and equilibrium time could reach 20 min. The adsorption mechanism of PVA/CMC-Zr-Ce revealed that ion exchange between hydroxide and fluoride, electrostatic interactions and complexation were the dominating influencing factors. Based on these findings, it can be concluded that PVA/CMC-Zr-Ce film- synthesized with high-speed shear assistance technique is a promising adsorbent for fluoride removal from water.

15.
J Hazard Mater ; 476: 134858, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38905983

RESUMO

Endemic fluorosis has gained increasing attention as a public health concern, and the escalating risk of colitis resulting from excessive fluoride intake calls for effective mitigation strategies. This study aimed to investigate the potential mechanisms underlying the alleviation of fluoride-induced colitis by Tea polysaccharides (TPS). Under conditions of excessive fluoride intake, significant changes were observed in the gut microbiota of rats, leading to aggravated colitis. However, the intervention of TPS exerted a notable alleviating effect on colitis symptoms. Antibiotic intervention and fecal microbiota transplantation (FMT) experiments provided evidence that TPS-mediated relief of fluoride-induced colitis is mediated through its effects on the gut microbiota. Furthermore, TPS supplementation was found to modulate the structure of gut microbiota, enhance the relative abundance of Limosilactobacillus vaginalis in the gut microbiota, and promote the expression of short-chain fatty acid (SCFAs) receptors in colonic tissue. Notably, L. vaginalis played a significant role in alleviating fluoride-induced colitis and facilitating the absorption of butyric acid in the rat colon. Subsequent butyric acid intervention experiments confirmed its remarkable alleviating effect on fluoride-induced colitis. Overall, these findings provide a potential preventive strategy for fluoride-induced colitis by TPS intervention, which is mediated by L. vaginalis and butyric acid.

16.
Food Chem ; 423: 136305, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37178597

RESUMO

Huajiao is a highly valued spice that is susceptible to fraudulent adulteration, particularly the addition of edible oils to increase weight and improve color. Nuclear magnetic resonance (1H NMR) and chemometrics were used to analyze 120 huajiao samples adulterated with different types and levels of edible oils. Using untargeted data and partial least squares-discriminant analysis (PLS-DA), the discrimination rate between types of adulteration reached 100% accuracy, and the R2 value of the prediction set for the level of adulteration using the targeted analysis dataset combined with PLS-regression methods reached 0.99. Triacylglycerols, major components of edible oils, were identified as a marker of adulteration through the variable importance in projection of the PLS-regression. A quantitative method based on the sn-3 triacylglycerol signal was developed that can achieve a detection limit of 0.11%. Testing of 28 market samples showed adulteration with various edible oils, with adulteration rates ranging from 0.96% to 4.41%.


Assuntos
Zanthoxylum , Espectroscopia de Prótons por Ressonância Magnética , Quimiometria , Óleos de Plantas/análise , Espectroscopia de Ressonância Magnética , Contaminação de Alimentos/análise
17.
Foods ; 12(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38231785

RESUMO

American ginseng (Panax quinquefolius L.) is known for its health benefits, which are attributed to various terpenoids. However, the specific composition and activities of these terpenoids in forest-grown wild American ginseng remain understudied. This study aimed to characterize the terpenoid composition, particularly triterpene saponins, in forest-grown wild American ginseng. The analysis revealed that triterpene saponins, notably American ginseng ginsenosides (AGGs), are the predominant active components, as identified through LC-MS/MS and HPLC. A subsequent in vitro evaluation of AGGs showcased their potent antioxidant capabilities, displaying the dose-dependent scavenging of free radicals and reducing agents. Moreover, AGGs demonstrated efficacy in reducing oxidative injury and intracellular ROS levels in RAW 264.7 macrophages treated with H2O2. In addition to their antioxidant properties, AGGs exhibited anti-inflammatory effects, significantly inhibiting NO and inflammatory substance production in lipopolysaccharide-treated RAW 264.7 macrophages. These findings highlight the potential of AGG-rich forest-grown wild American ginseng as a functional food with promising implications for improving human health.

18.
Toxics ; 11(7)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37505593

RESUMO

4,4'-dinitrocarbanilide (DNC) is a key component and marker residue of nicarbazin, which forms residues in edible tissue and then causes nephrotoxicity and hepatotoxicity in humans if used excessively. To simplify sample preparation and monitor the DNC rapidly and accurately, a comparable icELISA and lateral flow immunoassay (LFIA) was developed in this study. Briefly, the reaction parameters were explored for improving the sensitivity of icELISA and LFIA. Under the optimal conditions, methanol was selected as the extracting solvent for DNC in chicken, and 20- and 10-fold dilutions of sample extraction eliminated the matrix effect for icELISA and LFIA, separately. After sample pretreatment, the analysis properties of icELISA and LFIA were compared. The limit of detection of icELISA for DNC was 0.8 µg/kg, and the visual and quantitative limits of detection of LFIA were 8 and 2.5 µg/kg. Compared with icELISA, LFIA showed lower sensitivity but obvious advantages in terms of matrix tolerance and detection time (within 15 min). The sensitivity, specificity, and accuracy of the developed assays satisfied the detection requirement even if using simple sample pretreatment. This comparable icELISA and LFIA provided mutual verifiability methods for the accurate detection of DNC in chicken.

19.
Int J Biol Macromol ; 243: 125155, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37268075

RESUMO

A novel and easily separable adsorbent in the shape of a membrane for the rapid removal of fluoride from water was prepared after testing Zr, La and LaZr to modify a chitosan/polyvinyl alcohol composite adsorbent (CS/PVA-Zr, CS/PVA-La, CS/PVA-LA-Zr). The CS/PVA-La-Zr composite adsorbent can remove a large amount of fluoride within 1 min of contact time, and the adsorption equilibrium can be reached within 15 min. The fluoride adsorption behavior of the CS/PVA-La-Zr composite can be described by pseudo-second-order kinetics and Langmuir isotherms models. The morphology and structure of the adsorbents were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The adsorption mechanism was studied using Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS), and which showed that ion exchange occurred mainly with hydroxide and fluoride ions. This study showed that an easily operable, low-cost and environmentally friendly CS/PVA-La-Zr has the potential to remove fluoride effectively from drinking water in a short time.


Assuntos
Quitosana , Água Potável , Poluentes Químicos da Água , Fluoretos/química , Quitosana/química , Álcool de Polivinil , Lantânio/química , Zircônio/química , Adsorção , Espectroscopia de Infravermelho com Transformada de Fourier , Cinética , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/química
20.
Food Chem ; 425: 136538, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37300997

RESUMO

The narrow geographical traceability of green tea is both important and challenging. This study aimed to establish multi-technology metabolomic and chemometric approaches to finely discriminate the geographic origins of green teas. Taiping Houkui green tea samples were analyzed by headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry and 1H NMR of polar (D2O) and non-polar (CDCl3). Common dimension, low-level and mid-level data fusion approaches were tested to verify if the combination of several analytical sources can improve the classification ability of samples from different origins. In assessments of tea from six origins, the single instrument data test set results in 40.00% to 80.00% accuracy. Data fusion improved single-instrument performance classification with mid-level data fusion to obtain 93.33% accuracy in the test set. These results provide comprehensive metabolomic insights into the origin of TPHK fingerprinting and open up new metabolomic approaches for quality control in the tea industry.


Assuntos
Chá , Compostos Orgânicos Voláteis , Chá/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Microextração em Fase Sólida/métodos , Quimiometria , Espectroscopia de Prótons por Ressonância Magnética , Compostos Orgânicos Voláteis/análise
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