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Determination of pesticide residues remains a challenge in traditional Chinese medicines in which complex compounds may interfere with analysis signals. This study reports the development of a simple, effective, and high-throughput method combining gas chromatography-tandem mass spectrometry (GC-MS/MS) with either QuEChERS or solid phase extraction (SPE) to determine 147 pesticide residues in traditional Chinese medicines simultaneously. In SPE, the mixture of n-hexane and ethyl acetate (1:1, v/v) was selected to extract 147 pesticides in honeysuckle, and the extracted pesticides were determined by GC-MS/MS. The limits of detection for all pesticides were within 0.01-0.05 mg/kg. The recoveries were within 70-120% and the relative standard deviations were below 20% for over 90% pesticides. The coefficients of determination were up to 0.999 for the linearity between MS signals and different concentrations of pesticides (20-200 ng/mL). The analytical performance was confirmed in determining pesticide residues in dried tangerine peel. SPE achieved comparable recoveries for all pesticides compared to the QuEChERS method.
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Traditional Chinese herbal medicines are subject to heavy metal contamination. Standard detection methods are too complicated, time-consuming, and expensive for routine analysis, so low-cost methods are in high demand for rapid on-site screening. This study reports a high-sensitivity X-ray fluorescence (HS-XRF) method to determine As, Pb, and Cd residues simultaneously in herbal medicines. It couples monochromatic excitation energy dispersive X-ray fluorescence spectrometry and the fast fundamental parameters method. Each test takes only 10-30 min and costs 1/10th to 1/5th of the standard method. The detection limits, precision and accuracy were evaluated using different approaches, and application notes in practice are also proposed. This study is the first attempt to establish and evaluate HS-XRF in analyzing multiple heavy metals in herbal medicines. This rapid screening method would promote the testing efficiency and thus improve the monitoring of heavy metal contamination in herbal medicines.
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Metales Pesados , Plantas Medicinales , China , Contaminación de Medicamentos/prevención & control , Metales Pesados/análisis , Plantas Medicinales/química , Espectrometría por Rayos X/métodosRESUMEN
Food detection technologies play a vital role in ensuring food safety in the supply chains. Conventional food detection methods for biological, chemical, and physical contaminants are labor-intensive, expensive, time-consuming, and often alter the food samples. These limitations drive the need of the food industry for developing more practical food detection tools that can detect contaminants of all three classes. Raman spectroscopy can offer widespread food safety assessment in a non-destructive, ease-to-operate, sensitive, and rapid manner. Recent advances of Raman spectroscopic methods further improve the detection capabilities of food contaminants, which largely boosts its applications in food safety. In this review, we introduce the basic principles of Raman spectroscopy, surface-enhanced Raman spectroscopy (SERS), and micro-Raman spectroscopy and imaging; summarize the recent progress to detect biological, chemical, and physical hazards in foods; and discuss the limitations and future perspectives of Raman spectroscopic methods for food safety surveillance. This review is aimed to emphasize potential opportunities for applying Raman spectroscopic methods as a promising technique for food safety detection.
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Contaminación de Alimentos , Inocuidad de los Alimentos/métodos , Espectrometría Raman/métodos , Suplementos DietéticosRESUMEN
BACKGROUND: At present, Liver Cirrhosis (LC) is common in most later liver and gallbladder diseases that its morbidity and mortality seriously affect human health. The limitation and effectiveness of western medicine on LC have become a huge clinical challenge. However, a large number of clinical studies have shown that Yi-guan decoction has become a complementary treatment for LC. Therefore, this systematic review will aim to explore the safety and feasibility of Yi-guan decoction in the treatment of LC. METHODS: We will conduct a comprehensive literature search in Medline, PubMed, Cochrane Database of Systematic Reviews, Embase, Chinese Biomedical Literatures Database, China National Knowledge Infrastructure, Wang Fang Database, Chinese Scientific Journal Database from inception to December 2020 without any language restriction, In addition, relevant literature will be searched manually. The main subject terms searched: "Yi-guan decoction" "cirrhosis" "LC". Data entry will be performed by 2 researchers separately. Primary outcomes will be concluded: Liver function indicators: Total bilirubin, Alanine transaminase, Aspartate aminotransferase, etc. Secondary outcome indicators: Total effective rate, Nutrition index, Survival analysis, Adverse events; All randomized controlled trials collected in this study will be evaluated and rated using the Cochrane risk-of-biasassessment tool. Meta-analysis will be performed using RevMan 5.4.0 software. The heterogeneity test will be conducted between the studies, Pâ<â.1 and I2â>â50% are the thresholds for the tests. Using solid effect model or random effect model will be based on its heterogeneity value. RESULTS: This systematic review provides a theoretical basis for Yi-guan decoction to treat LC, we will report this result soon. CONCLUSION: This study will explore Yi-guan decoction can will be used as one of the non drug therapies to prevent or treat LC. TRIAL REGISTRATION NUMBER: INPLASY2020120114.
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Medicamentos Herbarios Chinos/uso terapéutico , Cirrosis Hepática/tratamiento farmacológico , Humanos , Metaanálisis como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación , Revisiones Sistemáticas como Asunto , Resultado del TratamientoRESUMEN
Escherichia coli O157:H7 and Salmonella enterica are leading causes of foodborne outbreaks linked to fresh produce. Both species can enter the "viable but nonculturable" (VBNC) state that precludes detection using conventional culture-based or molecular methods. In this study, we assessed propidium monoazide-quantitative PCR (PMA-qPCR) assays and novel methods combining PMA and loop-mediated isothermal amplification (LAMP) for the detection and quantification of VBNC E. coli O157:H7 and S. enterica in fresh produce. The performance of PMA-LAMP assays targeting the wzy gene of E. coli O157:H7 and the agfA gene of S. enterica and the performance of PMA-qPCR assays were compared in pure culture and spiked tomato, lettuce, and spinach. No cross-reaction was observed in the specificity tests. The values representing the limit of detection (LOD) seen with PMA-LAMP were 9.0 CFU/reaction for E. coli O157:H7 and 4.6 CFU/reaction for S. enterica in pure culture and were 5.13 × 103 or 5.13 × 104 CFU/g for VBNC E. coli O157:H7 and 1.05 × 104 or 1.05 × 105 CFU/g for VBNC S. enterica in fresh produce, representing results comparable to those obtained by PMA-qPCR. Standard curves showed correlation coefficients ranging from 0.925 to 0.996, indicating a good quantitative capacity of PMA-LAMP for determining populations of both bacterial species in the VBNC state. The PMA-LAMP assay was completed with considerable economy of time (30 min versus 1 h) and achieved sensitivity and quantitative capacity comparable to those seen with a PMA-qPCR assay. PMA-LAMP is a rapid, sensitive, and robust method for the detection and quantification of VBNC E. coli O157:H7 and S. enterica in fresh produce.IMPORTANCE VBNC pathogenic bacteria pose a potential risk to the food industry because they do not multiply on routine microbiological media and thus can evade detection in conventional plating assays. Both E. coli O157:H7 and S. enterica have been reported to enter the VBNC state under a range of environmental stress conditions and to resuscitate under favorable conditions and are a potential cause of human infections. PMA-LAMP methods developed in this study provide a rapid, sensitive, and specific way to determine levels of VBNC E. coli O157:H7 and S. enterica in fresh produce, which potentially decreases the risks related to the consumption of fresh produce contaminated by enteric pathogens in this state. PMA-LAMP can be further applied in the field study to enhance our understanding of the fate of VBNC pathogens in the preharvest and postharvest stages of fresh produce.
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Escherichia coli O157/aislamiento & purificación , Microbiología de Alimentos/métodos , Viabilidad Microbiana , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Salmonella enterica/aislamiento & purificación , Azidas/química , Lactuca/microbiología , Solanum lycopersicum/microbiología , Propidio/análogos & derivados , Propidio/química , Spinacia oleracea/microbiologíaRESUMEN
BACKGROUND: Litter size affects fetal development but its relation to diet-induced fatty liver later in life is unknown. OBJECTIVES: This aim of this study was to test the hypothesis that litter size influences postweaning fatty liver development in response to soybean oil-supplemented diet. METHODS: Weanling twin (TW) or triplet (TP) male lambs (n = 16) were fed a control diet or 2% soybean oil-supplemented diet (SO) for 90 d. Liver tissue morphology, biochemical parameters, and lipid metabolic enzymes were determined. Hepatic gene expression was analyzed by RNA sequencing (n = 3), followed by enrichment analysis according to Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes. Differentially expressed genes involved in lipid metabolism were further verified by quantitative reverse transcriptase-polymerase chain reaction (n = 4). All data were analyzed by a 2-factor ANOVA, apart from differentially expressed genes, which were identified by the Benjamini-Hochberg approach (q value ≤0.05). RESULTS: SO increased liver triglyceride (by 55%) and nonesterified fatty acid (by 54%) concentrations in TPs (P ≤ 0.05) but not in TWs (P > 0.05). SO also induced a 2.3- and 2.1-fold increase in the liver steatosis score of TPs and TWs, respectively (P ≤ 0.05). Moreover, SO reduced the activity of lipolytic enzymes including hepatic lipase and total lipase in TPs by 47% and 25%, respectively (P ≤ 0.05). In contrast, activities of lipogenic enzymes, including malic enzyme and acetyl coenzyme A carboxylase, were significantly higher in TPs (P ≤ 0.05). Moreover, TPs had higher expression of lipogenic genes, such as FASN (by 45%) and APOB (by 72%), and lower expression of lipolytic genes, such as PRKAA2 (by 28%) and CPT1A (by 43%), compared with TWs (P ≤ 0.05). CONCLUSIONS: TPs have a gene expression profile that is more susceptible to SO-induced fatty liver than that of TWs, which indicates that insufficient maternal nutrient supply at fetal and neonatal stages may increase the risk of nonalcoholic fatty liver disease.
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Suplementos Dietéticos/efectos adversos , Tamaño de la Camada/fisiología , Enfermedad del Hígado Graso no Alcohólico/etiología , Aceite de Soja/administración & dosificación , Aceite de Soja/efectos adversos , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Modelos Animales de Enfermedad , Femenino , Metabolismo de los Lípidos/genética , Hígado/metabolismo , Hígado/patología , Masculino , Intercambio Materno-Fetal/fisiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Embarazo , Fenómenos Fisiologicos de la Nutrición Prenatal/fisiología , Oveja DomésticaRESUMEN
Black phosphorus (BP), also known as phosphorene, has attracted recent scientific attention since its first successful exfoliation in 2014 owing to its unique structure and properties. In particular, its exceptional attributes, such as the excellent optical and mechanical properties, electrical conductivity and electron-transfer capacity, contribute to its increasing demand as an alternative to graphene-based materials in biomedical applications. Although the outlook of this material seems promising, its practical applications are still highly challenging. In this review article, we discuss the unique properties of BP, which make it a potential platform for biomedical applications compared to other 2D materials, including graphene, molybdenum disulphide (MoS2), tungsten diselenide (WSe2) and hexagonal boron nitride (h-BN). We then introduce various synthesis methods of BP and review its latest progress in biomedical applications, such as biosensing, drug delivery, photoacoustic imaging and cancer therapies (i.e., photothermal and photodynamic therapies). Lastly, the existing challenges and future perspective of BP in biomedical applications are briefly discussed.
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Técnicas Biosensibles/métodos , Sistemas de Liberación de Medicamentos , Fósforo/química , Fósforo/aislamiento & purificación , Técnicas Fotoacústicas/métodos , Fototerapia/métodos , Investigación Biomédica/tendencias , Humanos , Fósforo/administración & dosificaciónRESUMEN
Noxa, a pro-apoptotic protein, plays an important role in cell apoptosis. The researches about noxa gene were concentrated in mammalians, whereas the role and transcriptional regulatory mechanism of noxa in fish were still unclear. In this study, the expression pattern and transcriptional regulatory mechanism of noxa gene in grass carp were analyzed. Noxa was constitutively expressed in all the examined tissues but the relative expression level differed. After exposure to grass carp reovirus (GCRV), mRNA expression level of noxa was down-regulated at the early phase whereas up-regulated at the late phase of infection. Luciferase assays showed that the promoter region -867 â¼ +107 of noxa had high activity and the region -678 â¼ -603 was important in the response to GCRV infection. By deleting the predicted transcription factor binding sites, transcription factors FOXO1 and CEBPß were found important for noxa in response to GCRV infection. Moreover, the noxa promoter was biotin-labeled and incubated with nuclear extracts from GCRV infected cells. Mass spectrometry analysis showed that transcription factors FOXO1 and CEBPß were also enriched in the combined proteins. Therefore, the results suggested that transcription factors FOXO1 and CEBPß may play an important role in the regulation of noxa. Our study would provide new insight into the transcriptional regulatory mechanism of noxa in teleost fish.
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Carpas/genética , Proteínas de Peces/genética , Regulación de la Expresión Génica , Animales , Secuencia de Bases , Carpas/metabolismo , Clonación Molecular , ADN Complementario/genética , ADN Complementario/metabolismo , Proteínas de Peces/metabolismo , Luciferasas/genética , Luciferasas/metabolismo , Datos de Secuencia Molecular , Regiones Promotoras Genéticas , ARN Mensajero/genética , ARN Mensajero/metabolismoRESUMEN
Lycopene, a red non-provitamin A carotenoid, mainly presenting in tomato and tomato byproducts, has the highest antioxidant activity among carotenoids because of its high number of conjugated double bonds. The objective of this study was to investigate the effect of lycopene supplementation in the diet on plasma lipid profile, lipid peroxidation and antioxidant defense system in feedlot lamb. Twenty-eight Bamei male lambs (90 days old) were divided into four groups and fed a basal diet (LP0, 40:60 roughage: concentrate) or the basal diet supplemented with 50, 100, and 200 mg/kg lycopene. After 120 days of feeding, all lambs were slaughtered and sampled. Dietary lycopene supplementation significantly reduced the levels of plasma total cholesterol (p<0.05, linearly), total triglycerides (TG, p<0.05) and low-density lipoprotein cholesterol (LDL-C, p<0.05), as well as atherogenic index (p<0.001), whereas no change was observed in high-density lipoprotein cholesterol (p>0.05). The levels of TG (p<0.001) and LDL-C (p<0.001) were decreased with the feeding time extension, and both showed a linear trend (p<0.01). Malondialdehyde level in plasma and liver decreased linearly with the increase of lycopene inclusion levels (p<0.01). Dietary lycopene intake linearly increased the plasma antioxidant vitamin E level (p<0.001), total antioxidant capacity (T-AOC, p<0.05), and activities of catalase (CAT, p<0.01), glutathione peroxidase (GSH-Px, p<0.05) and superoxide dismutase (SOD, p<0.05). The plasma T-AOC and activities of GSH-Px and SOD decreased with the extension of the feeding time. In liver, dietary lycopene inclusion showed similar antioxidant effects with respect to activities of CAT (p<0.05, linearly) and SOD (p<0.001, linearly). Therefore, it was concluded that lycopene supplementation improved the antioxidant status of the lamb and optimized the plasma lipid profile, the dosage of 200 mg lycopene/kg feed might be desirable for growing lambs to prevent environment stress and maintain normal physiological metabolism.
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Sudan I is a carcinogenic and mutagenic azo-compound that has been utilized as a common adulterant in spice and spice blends to impart a desirable red color to foods. A novel biosensor combining molecularly imprinted polymers (MIPs), thin layer chromatography (TLC) and surface enhanced Raman spectroscopy (SERS) could determine Sudan I levels in paprika powder to 1 ppm (or 2 ng/spot). Sudan I spiked paprika extracts (spiking levels: 0, 1, 5, 10, 40, 70 and 100 ppm) were prepared. Sudan I imprinted polymers were synthesized by employing the interaction between Sudan I (template) and methacrylic acid (functional monomer), followed by washing to remove Sudan I leaving the Sudan I-binding sites exposed. MIPs were used as a stationary phase for TLC and could selectively retain Sudan I at the original spot with little interference. A gold colloid SERS substrate could enhance Raman intensity for Sudan I in this MIP-TLC system. Principal component analysis plot and partial least squares regression (R(2)=0.978) models were constructed and a linear regression model (R(2)=0.983) correlated spiking levels (5, 10, 40, 70 and 100 ppm) with the peak intensities (721 cm(-1)) of Sudan I SERS spectra. Both separation (30-40s) and detection (1s or 0.1s) were extremely fast by using both commercial bench-top and custom made portable Raman spectrometers. This biosensor can be applied as a rapid, low-cost and reliable tool for screening Sudan I adulteration in foods.
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Técnicas Biosensibles , Capsicum , Colorantes/análisis , Naftoles/análisis , Preparaciones de Plantas/análisis , Especias/análisis , Cromatografía en Capa Delgada , Colorantes/química , Contaminación de Alimentos/análisis , Impresión Molecular , Naftoles/química , Polímeros/química , Polvos , Espectrometría RamanRESUMEN
We have developed a silver nanofilm-coated porous anodic aluminum oxide (AAO) as a surface-enhanced Raman scattering (SERS)-active substrate for the detection of trace level of chloramphenicol, a representative antibiotic in food systems. The ordered aluminum template generated during the synthesis of AAO serves as a patterned matrix on which a coated silver film replicates the patterned AAO matrix to form a 2-dimensional ordered nanostructure. We used atomic force microscopy and scanning electron microscopy images to determine the morphology of this nanosubstrate, and characterized its localized surface plasmon resonance by ultraviolet-visible reflection. We gauged the SERS effect of this nanosubstrate by confocal micro-Raman spectroscopy (782-nm laser), finding a satisfactory and consistent performance with enhancement factors of approximately 2 × 10(4) and a limit of detection for chloramphenicol of 7.5 ppb. We applied principal component analysis to determine the limit of quantification for chloramphenicol of 10 ppb. Using electromagnetic field theory, we developed a detailed mathematical model to explain the mechanism of Raman signal enhancement of this nanosubstrate. With simple sample pretreatment and separation steps, this silver nanofilm-coated AAO substrate could detect 50 ppb chloramphenicol in milk, indicating good potential as a reliable SERS-active substrate for rapid detection of chemical contaminants in agricultural and food products.
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Óxido de Aluminio/química , Aluminio/química , Antibacterianos/análisis , Contaminación de Alimentos/análisis , Nanoestructuras/química , Plata/química , Espectrometría Raman/métodos , Cloranfenicol/análisis , Microscopía de Fuerza Atómica , Microscopía Electrónica de Rastreo , Óxidos , Porosidad , Compuestos de PlataRESUMEN
We present the results of a study using high-throughput whole-transcriptome sequencing (RNA-seq) and vibrational spectroscopy to characterize and fingerprint pathogenic-bacterium injury under conditions of unfavorable stress. Two garlic-derived organosulfur compounds were found to be highly effective antimicrobial compounds against Cronobacter sakazakii, a leading pathogen associated with invasive infection of infants and causing meningitis, necrotizing entercolitis, and bacteremia. RNA-seq shows changes in gene expression patterns and transcriptomic response, while confocal micro-Raman spectroscopy characterizes macromolecular changes in the bacterial cell resulting from this chemical stress. RNA-seq analyses showed that the bacterial response to ajoene differed from the response to diallyl sulfide. Specifically, ajoene caused downregulation of motility-related genes, while diallyl sulfide treatment caused an increased expression of cell wall synthesis genes. Confocal micro-Raman spectroscopy revealed that the two compounds appear to have the same phase I antimicrobial mechanism of binding to thiol-containing proteins/enzymes in bacterial cells generating a disulfide stretching band but different phase II antimicrobial mechanisms, showing alterations in the secondary structures of proteins in two different ways. Diallyl sulfide primarily altered the α-helix and ß-sheet, as reflected in changes in amide I, while ajoene altered the structures containing phenylalanine and tyrosine. Bayesian probability analysis validated the ability of principal component analysis to differentiate treated and control C. sakazakii cells. Scanning electron microscopy confirmed cell injury, showing significant morphological variations in cells following treatments by these two compounds. Findings from this study aid in the development of effective intervention strategies to reduce the risk of C. sakazakii contamination in the food production environment and on food contact surfaces, reducing the risks to susceptible consumers.
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Compuestos Alílicos/farmacología , Antibacterianos/farmacología , Cronobacter sakazakii/efectos de los fármacos , Disulfuros/farmacología , Ajo/química , Espectrometría Raman , Sulfuros/farmacología , Transcriptoma , Compuestos Alílicos/aislamiento & purificación , Antibacterianos/aislamiento & purificación , Cronobacter sakazakii/ultraestructura , Disulfuros/aislamiento & purificación , Microscopía Electrónica de Rastreo , Conformación Proteica/efectos de los fármacos , Sulfuros/aislamiento & purificación , SulfóxidosRESUMEN
We report the development of a novel hybrid "capture-detection" molecularly imprinted polymers-surface-enhanced Raman spectroscopic (MIPs-SERS) biosensor for the detection and quantification of α-tocopherol (α-Toc) in vegetable oils. α-Toc served as the template for MIPs synthesis. Methacrylic acid formed as the functional monomer. Ethylene glycol dimethacrylate was the cross-linking agent, and 2,2'-azobisisobutyronitrile was used as the initiator. The synthesized MIPs functioned to rapidly and selectively adsorb and separate α-Toc from oil components. We validated a dendritic silver nanostructure synthesized by a displacement reaction to be a suitable SERS substrate for the enhancement of Raman signals. Second-derivative transformations and chemometric models based upon SERS spectral features confirmed the possibility of a rapid and precise detection and quantification of different spiking levels of α-Toc in four different sources of vegetable oils (Mahalanobis distance from 15.93 to 34.01 for PCA model; R > 0.92, RMSE < 0.41 for PLSR model). The MIPs-SERS biosensor had a high sensitivity as well as a good recovery for α-Toc analysis in vegetable oils. The entire analysis required 15 min or less to complete with limited sample preparation.
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Aceites de Plantas/análisis , Polímeros/química , Espectrometría Raman/métodos , alfa-Tocoferol/análisis , Impresión Molecular , Polímeros/síntesis química , Espectrometría Raman/instrumentaciónRESUMEN
Developing rapid analytical methods for bioactive components and predicting both the concentration and biological availability of nutraceutical components in foods is a topic of growing interest. Here, analysis of bioactive components and total antioxidant activity in food matrices using infrared spectroscopy coupled with chemometric predictive models is described. Infrared spectroscopy offers an alternative to wet chemistry, chromatographic determination of antioxidants, and in vitro biochemical assays for assessment of antioxidant activity. Spectroscopic methods provide a technique that can be used with biological tissues without extraction, which can often lead to degradation of the antioxidant components. Sample preparation time greatly decreases and analysis time is very short once a predictive model has been developed. Spectroscopic methods can have a high degree of precision when applied to analysis of nutraceutical compound concentration and antioxidant activity in foods. This article summarizes recent advances in vibrational spectroscopy and chemometrics and applications of these methods for antioxidant detection in foods.
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Antioxidantes/análisis , Antioxidantes/metabolismo , Análisis de los Alimentos/métodos , Espectrofotometría Infrarroja/métodos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Suplementos Dietéticos/análisis , Frutas , Metabolismo de los Lípidos , Extractos Vegetales/análisis , Extractos Vegetales/metabolismo , Té/química , Vino/análisisRESUMEN
Fourier transform infrared (FT-IR) spectroscopy and Raman spectroscopy were used to study the cell injury and inactivation of Campylobacter jejuni from exposure to antioxidants from garlic. C. jejuni was treated with various concentrations of garlic concentrate and garlic-derived organosulfur compounds in growth media and saline at 4, 22, and 35°C. The antimicrobial activities of the diallyl sulfides increased with the number of sulfur atoms (diallyl sulfide < diallyl disulfide < diallyl trisulfide). FT-IR spectroscopy confirmed that organosulfur compounds are responsible for the substantial antimicrobial activity of garlic, much greater than those of garlic phenolic compounds, as indicated by changes in the spectral features of proteins, lipids, and polysaccharides in the bacterial cell membranes. Confocal Raman microscopy (532-nm-gold-particle substrate) and Raman mapping of a single bacterium confirmed the intracellular uptake of sulfur and phenolic components. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to verify cell damage. Principal-component analysis (PCA), discriminant function analysis (DFA), and soft independent modeling of class analogs (SIMCA) were performed, and results were cross validated to differentiate bacteria based upon the degree of cell injury. Partial least-squares regression (PLSR) was employed to quantify and predict actual numbers of healthy and injured bacterial cells remaining following treatment. PLSR-based loading plots were investigated to further verify the changes in the cell membrane of C. jejuni treated with organosulfur compounds. We demonstrated that bacterial injury and inactivation could be accurately investigated by complementary infrared and Raman spectroscopies using a chemical-based, "whole-organism fingerprint" with the aid of chemometrics and electron microscopy.
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Antibacterianos/farmacología , Campylobacter jejuni/efectos de los fármacos , Ajo/química , Ajo/metabolismo , Compuestos Alílicos/farmacología , Antioxidantes/farmacología , Campylobacter jejuni/química , Campylobacter jejuni/crecimiento & desarrollo , Campylobacter jejuni/ultraestructura , Microscopía Electrónica , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman , Sulfuros/farmacología , Azufre/farmacologíaRESUMEN
The rapid quantification of flavonoid compounds in onions by attenuated total reflectance (ATR) Fourier transform infrared (FT-IR) spectroscopy combined with multivariate analysis was evaluated as a possible alternative to high-performance liquid chromatography (HPLC) analysis. Quercetin content in onion varieties (yellow, red, and sweet) was quantified using ATR FT-IR (4000 to 400 cm⻹) spectroscopy and HPLC methods. Quercetin-3,4'-O-diglucoside (3,4'-Qdg) and quercetin-4'-O-glucoside (4'-Qmg) comprised >80% of the total flavonol content detected in the studied varieties. The quercetin compounds (3,4'-Qdg and 4'-Qmg) and total flavonol conjugates were quantified by HPLC, and results correlated closely with ATR-IR values (R > 0.95). Cross-validated (leave-one-out) partial least-squares regression (PLSR) models successfully predicted concentrations of these quercetins. The standard errors of cross-validation (SECV) of 3,4'-Qdg and 4'-Qmg, total quercetin, and total flavonol contents of onions were 20.43, 21.18, and 21.02 mg/kg fresh weight, respectively. In addition, supervised and unsupervised segregation analyses (principal component analysis, discriminant function analysis, and soft independent modeling of class analogue) were performed to classify onion varieties on the basis of unique infrared spectral features. There was a high degree of segregation (interclass distances > 3.0) for the different types of onion. This study indicated that the IR technique could predict 3,4'-Qdg, 4'-Qmg, total quercetin, and total flavonol contents and has advantages over the traditional HPLC method in providing a valid, efficient, and cost-effective method requiring less sample preparation for the quantification of quercetins in onion.
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Cebollas/química , Extractos Vegetales/análisis , Quercetina/análisis , Espectrofotometría Infrarroja/métodosRESUMEN
The antimicrobial effects of garlic (Allium sativum) extract (25, 50, 75, 100, and 200 µL/ml) and diallyl sulfide (5, 10, and 20 µM) on Listeria monocytogenes and Escherichia coli O157:H7 cultivated in tryptic soy broth at 4, 22, and 35 °C for up to 7 days were investigated. L. monocytogenes was more resistant to garlic extract and diallyl compounds treatment than E. coli O157:H7. Fourier transform infrared (FT-IR) spectroscopy indicated that diallyl constituents contributed more to the antimicrobial effect than phenolic compounds. This effect was verified by Raman spectroscopy and Raman mapping on single bacteria. Scanning electron microscope (SEM) and transmission electron microscope (TEM) showed cell membrane damage consistent with spectroscopic observation. The degree of bacterial cell injury could be quantified using chemometric methods.
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Compuestos Alílicos/farmacología , Antiinfecciosos/farmacología , Ajo/química , Extractos Vegetales/farmacología , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Espectrometría Raman/métodos , Sulfuros/farmacología , Escherichia coli O157/efectos de los fármacos , Microbiología de Alimentos , Listeria monocytogenes/efectos de los fármacos , Microscopía Electrónica de Transmisión , Fenoles/farmacologíaRESUMEN
The total phenolic contents and antioxidant activities of garlics from California, Oregon, Washington, and New York were determined by Fourier transform infrared (FT-IR) spectroscopy (400-4000 cm(-1)). The total phenolic content was quantified [Folin-Ciocalteu assay (FC)] and three antioxidant activity assays, 2,2-diphenyl-picrylhydrazyl (DPPH) assay, Trolox equivalent antioxidant capacity (TEAC) assay, and ferric reducing antioxidant power (FRAP), were employed for reference measurements. Four independent partial least-squares regression (PLSR) models were constructed with spectra from 25 extracts and their corresponding FC, DPPH, TEAC, and FRAP with values for 20 additional extracts predicted (R > 0.95). The standard errors of calibration and standard error of cross-validation were <1.45 (TEAC), 0.36 (FRAP), and 0.33 µmol Trolox/g FW (DPPH) and 0.55 mg gallic acid/g FW (FC). Cluster and dendrogram analyses could segregate garlic grown at different locations. Hydroxyl and phenolic functional groups most closely correlated with garlic antioxidant activity.
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Allium/química , Antioxidantes/análisis , Ajo/química , Fenoles/análisis , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Análisis de los Mínimos CuadradosRESUMEN
OBJECTIVE: To observe the therapeutic effect and immune regulatory mechanism of Bushen Er'xian Decoction (BED) on patients with premature ovarian failure (POF). METHODS: Sixty patients with POF were randomly assigned to two groups in the ratio of 2:1, the 40 in the treatment group were treated with BED and the 20 in the control group were treated with artificial menstrual cycle therapy. The clinical efficacy was observed and the changes of serum reproductive hormone and T lymphocytes before and after treatment were observed. RESULTS: The total effective rate in the treatment group was 72.5% (29/40 cases), which was higher than that in the control group, 45.0% (9/20 cases, P < 0.05). Serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) decreased and estradiol (E2) increased in both groups after treatment (P <0.05), but the level of FSH was lower in the treatment group than in the control group (22.57 +/- 12.49 IU/L vs 31.10 +/- 14.50 IU/L, P <0.05). CD4 and CD4/CD8 increased, CD8 decreased in the treatment group after treatment, showing significant difference as compared with those before treatment and with those in the control group after treatment (P <0.01). CONCLUSION: BED is favourable for improving POF, being a good remedy with better clinical efficacy.
Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Insuficiencia Ovárica Primaria/tratamiento farmacológico , Adulto , Femenino , Hormona Folículo Estimulante/sangre , Humanos , Hormona Luteinizante/sangre , Persona de Mediana Edad , Insuficiencia Ovárica Primaria/sangre , Insuficiencia Ovárica Primaria/inmunología , Linfocitos T/inmunología , Resultado del TratamientoRESUMEN
OBJECTIVE: To observe the therapeutic effect of Kangyi Zhongyu Decoction (KZD) combined with gonadotropin releasing hormone-a (GnRH-a) on infertile patients with severe endometriosis. METHODS: Seventy-five infertile patients with the diagnosis of endometriosis confirmed by laparoscope who were scheduled to receive in vitro fertilization and embryo transfer (IVF-ET) were randomly assigned to three groups, they were treated respectively with KZD (A), GnRH-a (B) alone and combined of both (C), and IVF-ET were applied in the patients after 3 months of treatment. The clinical efficacy and adverse reactions in the three groups were observed and the changes of serum cancer antigen 125 (CA125) and endometrial antibody (EMAb) levels before and after treatment were tested. RESULTS: Score of dyspareunia in Group A and C was obvioushy lower than that in Group B after treatment (P <0.01). Pregnancy rate in Group C was higher than that in Group A and B (P <0.05), with the adverse reactions less than in Group B (P <0.01). The positive rate of plasma EMAb was reduced obviously after treatment in Group C with the level lower than that in the other two groups (P<0.05). CONCLUSION: The combined use of KZD and GnRH-a is a new method in treating infertile patients with severe endometriosis with ideal effectiveness and fewer adverse reactions, and it could advance the successful rate of reproductive assistant technique.