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1.
Molecules ; 26(18)2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34577141

RESUMO

We assessed the residual distribution and temporal trend of picarbutrazox sprayed by agricultural multicopters on Chinese cabbage and considered fortification levels and flying speeds. In plot 2, 14 days after the last spraying, the residues decreased by ~91.3% compared with those in the samples on day 0. The residues in the crops decreased by ~40.8% of the initial concentration owing to growth (dilution effect) and by ~50.6% after excluding the dilution effect. As the flight speed increased, picarbutrazox residues decreased (p < 0.05, least significant deviation [LSD]). At 2 m s-1 flight speed, the residual distribution differed from the dilution rate of the spraying solution. The average range of picarbutrazox residues at all sampling points was 0.007 to 0.486, below the limit of quantitation -0.395, 0.005-0.316, and 0.005-0.289 mg kg-1 in plots 1, 2, 3, and 4, respectively, showing significant differences (p < 0.05, LSD). These results indicated that the residual distribution of picarbutrazox sprayed by using a multicopter on the Chinese cabbages was not uniform. However, the residues were less than the maximum residue limit in all plots. Accordingly, picarbutrazox was considered to have a low risk to human health if it was sprayed on cabbage according to the recommended spraying conditions.


Assuntos
Brassica , Tetrazóis , Cromatografia Líquida , Resíduos de Praguicidas
2.
J Food Sci Technol ; 58(7): 2670-2676, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34194102

RESUMO

A simple, rapid and reliable extraction method for allulose content in jelly were optimized using response surface methodology. The extraction method was selected based on preliminary experiments, with a three-factor, three-level central complex design including 20 experimental runs to optimize the extraction parameters. The optimum extraction factors predicted were temperature of 66 °C, solvent of 74% (v/v) ethanol, and extraction time of 24 min under shaking water bath extraction. The measured parameters were in accordance with the predicted values. The developed analytical method was validated with regard to linearity, accuracy and precision presenting recovery level from 90.79 to 95.18% and detection limits varying from 0.53 to 1.62 mg/mL. Finally, the method will be potentially applicable to a commercial jelly food using optimum extraction.

3.
Molecules ; 25(15)2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32752108

RESUMO

An effective analytical method was optimized for residues including chlorpyrifos-methyl, deltamethrin, fenoxanil, thiobencarb and fludioxonil in mealworms, the larval form of Tenebrio molitor. They are listed for pest control during wheat cultivation and can be found in wheat-bran feed for growing mealworms in South Korea. Analytes were extracted using acetonitrile and salt packet. Four clean-up methods ((1) MgSO4 + 25 mg PSA + 25 mg C18; (2) MgSO4 + 50 mg PSA + 50 mg C18; (3) EMR-lipidTM tube; and (4) 10 mL n-hexane) were investigated and the method (1) was selected due to its robustness. Low-temperature precipitation of fat and proteins improved the recoveries. Recoveries from the Method (1) were satisfying with 70-120% with <20% relative SD at a spiking level of 0.01 mg/kg. With the simultaneous sample preparation, fenoxanil, thiobencarb and fludioxonil were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) and chlorpyrifos-methyl and deltamethrin by gas chromatography tandem mass spectrometry (GC-MS/MS). Quantification limits for LC-MS/MS and GC-MS/MS were 0.5 and 2.5 µg/L, respectively. No pesticides of interest were detected in 30 real samples collected across the nation. However, the data can be provided for establishing maximum residue limits for the pesticides in mealworms in response to the positive list system.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Tenebrio/química , Animais , Clorpirifos/análogos & derivados , Clorpirifos/análise , Clorpirifos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Imidazóis/análise , Imidazóis/isolamento & purificação , Larva/química , Larva/metabolismo , Limite de Detecção , Extração Líquido-Líquido , Nitrilas/análise , Nitrilas/isolamento & purificação , Resíduos de Praguicidas/isolamento & purificação , Piretrinas/análise , Piretrinas/isolamento & purificação , Tenebrio/crescimento & desenvolvimento , Tenebrio/metabolismo
4.
Molecules ; 25(24)2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33322485

RESUMO

Tenebrio molitor larvae (mealworm) is an edible insect and is considered a future food. Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), a novel method for simultaneous analysis of 353 target analytes was developed and validated. Various sample preparation steps including "quick, easy, cheap, effective, rugged, and safe" (QuEChERS) extraction conditions, number of acetonitrile-hexane partitions, and dispersive-solid phase extraction (dSPE) sorbents were compared, and the optimal conditions were determined. In the established method, 5 g of homogenized mealworms was extracted with acetonitrile and treated with QuEChERS EN 15662 salts. The crude extract was subjected to three rounds of acetonitrile-hexane partitioning, and the acetonitrile layer was cleaned with C18 dSPE. The final solution was matrix-matched and injected into LC-MS/MS (2 µL). For target analytes, the limits of quantitation (LOQs) were ≤10 µg/kg, and the correlation coefficient (r2) of calibration was >0.990. In recovery tests, more than 90% of the pesticides showed an excellent recovery range (70-120%) with relative standard deviation (RSD) ≤20%. For more than 94% of pesticides, a negligible matrix effect (within ±20%) was observed. The analytical method was successfully applied and used for the detection of three urea pesticides in 4 of 11 mealworm samples.


Assuntos
Cromatografia Líquida/métodos , Resíduos de Praguicidas/análise , Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Tenebrio/efeitos dos fármacos , Acetonitrilas/química , Animais , Calibragem , Insetos Comestíveis , Hexanos/química , Insetos , Larva , Limite de Detecção , Extração em Fase Sólida , Ureia/análise
5.
Opt Lett ; 44(15): 3681-3684, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31368942

RESUMO

We experimentally demonstrate Franson interference of a time-energy entangled photon pair generated via collective two-photon coherence in the 5S1/2-5P3/2-5D5/2 transition of warm Rb87 atoms. The two unbalanced Michelson interferometers used in our setup are spatially separated in order to understand entanglement as a nonlocal property of the photon pairs from the warm atomic ensemble. We observe a Franson interference fringe with a high visibility of 99.1±1.3% with continuous-wave-mode photon pairs from the cascade-type atomic ensemble. To the best of our knowledge, this work is the first demonstration of the nonlocal two-photon interference experiment in separated photon channels by use of two-photon pairs emitted from a cascade-type atomic system as originally proposed by Franson [Phys. Rev. Lett.62, 2205 (1989)PRLTAO0031-900710.1103/PhysRevLett.62.2205].

6.
J Sep Sci ; 42(14): 2379-2389, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31106518

RESUMO

A multi-residue method has been developed and validated to determine 46 pesticides in spinach using liquid chromatography tandem mass spectrometry. The method is based on modified quick, easy, cheap, effective, rugged, and safe sample preparation, where high-surface-area graphitized carbon black was used first as sorbent material in the dispersive solid-phase extraction. The method was compared with the quick, easy, cheap, effective, rugged, and safe method. The morphology, surface area, pore size, and pore volume of the sorbent was determined. The results obtained show that the sorbent consists of high surface area (233 m2 /g) and large pore volume (1.5 cm3 /g). The calibration curve correlation coefficient (R2 ) of the method was at least 0.99. The average recoveries ranged from 74 to 116%, and limits of detection and quantification from 0.0001 to 0.002 mg/kg and from 0.0002 to 0.005 mg/kg, respectively. Using the method, the pesticides exhibited low matrix effect (< 20%), except for nicosulfuron (29.86%), methomyl (26.77%), and flufenoxuron (24.65%). The method showed better potential to remove pigments than the quick, easy, cheap, effective, rugged, and safe method. It is demonstrated that the proposed method could be useful alternative for sample preparation of spinach and other matrices in future.


Assuntos
Aminas/química , Resíduos de Praguicidas/análise , Fuligem/química , Spinacia oleracea/química , Cromatografia Líquida de Alta Pressão , Tamanho da Partícula , Extração em Fase Sólida , Propriedades de Superfície , Espectrometria de Massas em Tandem
7.
J Food Sci Technol ; 55(10): 3930-3938, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30228391

RESUMO

In this article matrix components in spinach were investigated in detail. The samples were prepared using two QuEChERS (quick, easy, cheap, effective, rugged and safe) methods, AOAC and CEN. Liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS), gas chromatography-mass spectrometry (GC-MS) and ultra performance liquid chromatography-diode array detector (UPLC-DAD), were applied for component identification. The strategies of identification by LC-ESI-MS/MS include accurate mass spectra of the parent ion, comparison with previous literature data and investigation of the mass spectral decomposition pattern. Overall, fourteen components were identified by LC-ESI-MS/MS in each methods of AOAC and CEN, which were phytosteroids, flavonoids, fatty acids and fatty acid amides. Fifty components using AOAC method and fifty-seven components using CEN method were identified in GC-MS by comparing mass data with the National Institute of Standards and Technology (NIST, U.S.) database. The results indicate that the major components of the matrix are terpenoids, fatty acids and fatty acid esters. Moreover, three pigments (neoxanthin, violaxanthin and lutein) in the AOAC method and eight pigments (neoxanthin, violaxanthin, zeaxanthin, lutein, chlorophyll a, chlorophyll b, pheophytin a and beta-carotene) in the CEN method that gave a characteristics peak at 440 nm were identified by the UPLC-DAD. According to the sample preparation condition using different amounts of graphitized carbon black (GCB) in this study, the AOAC method had higher matrix component removal efficiency than the CEN method. A better understanding of matrix components would increase the current knowledge for improvement of existing QuEChERS methodology, as well as contribute to new method developments.

8.
Breast Cancer Res ; 18(1): 9, 2016 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-26781438

RESUMO

BACKGROUND: Triple-negative breast cancer (TNBC), an aggressive disease comprising several subtypes including basal-like and claudin-low, involves frequent deletions or point mutations in TP53, as well as loss of PTEN. We previously showed that combined deletion of both tumor suppressors in the mouse mammary epithelium invariably induced claudin-low-like TNBC. The effect of p53 mutation plus Pten deletion on mammary tumorigenesis and whether this combination can induce basal-like TNBC in the mouse are unknown. METHODS: WAP-Cre:Pten(f/f):p53(lox.stop.lox_R270H) composite mice were generated in which Pten is deleted and a p53-R270H mutation in the DNA-binding domain is induced upon expression of Cre-recombinase in pregnancy-identified alveolar progenitors. Tumors were characterized by histology, marker analysis, transcriptional profiling [GEO-GSE75989], bioinformatics, high-throughput (HTP) FDA drug screen as well as orthotopic injection to quantify tumor-initiating cells (TICs) and tail vein injection to identify lung metastasis. RESULTS: Combined Pten deletion plus induction of p53-R270H mutation accelerated formation of four distinct mammary tumors including poorly differentiated adenocarcinoma (PDA) and spindle/mesenchymal-like lesions. Transplantation assays revealed highest frequency of TICs in PDA and spindle tumors compared with other subtypes. Hierarchical clustering demonstrated that the PDA and spindle tumors grouped closely with human as well as mouse models of basal and claudin-low subtypes, respectively. HTP screens of primary Pten(∆):p53(∆) vs. Pten(∆):p53(R270H) spindle tumor cells with 1120 FDA-approved drugs identified 8-azaguanine as most potent for both tumor types, but found no allele-specific inhibitor. A gene set enrichment analysis revealed increased expression of a metastasis pathway in Pten(∆):p53(R270H) vs. Pten(∆):p53(∆) spindle tumors. Accordingly, following tail vein injection, both Pten(∆):p53(R270H) spindle and PDA tumor cells induced lung metastases and morbidity significantly faster than Pten(∆):p53(∆) double-deletion cells, and this was associated with the ability of Pten(∆):p53(R270H) tumor cells to upregulate E-cadherin expression in lung metastases. CONCLUSIONS: Our results demonstrate that WAP-Cre:Pten(f/f):p53(lox.stop.lox_R270H) mice represent a tractable model to study basal-like breast cancer because unlike p53 deletion, p53(R270H) mutation in the mouse does not skew tumors toward the claudin-low subtype. The WAP-Cre:Pten(f/f):p53(lox.stop.lox_R270H) mice develop basal-like breast cancer that is enriched in TICs, can readily form lung metastasis, and provides a preclinical model to study both basal-like and claudin-low TNBC in immune-competent mice.


Assuntos
Neoplasias Mamárias Animais/genética , Neoplasia de Células Basais/genética , PTEN Fosfo-Hidrolase/genética , Neoplasias de Mama Triplo Negativas/genética , Proteína Supressora de Tumor p53/genética , Animais , Caderinas/genética , Claudinas/genética , Epitélio/metabolismo , Epitélio/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Glândulas Mamárias Humanas/metabolismo , Glândulas Mamárias Humanas/patologia , Neoplasias Mamárias Animais/patologia , Camundongos , Neoplasia de Células Basais/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , PTEN Fosfo-Hidrolase/metabolismo , Gravidez , Deleção de Sequência/genética , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Proteína Supressora de Tumor p53/metabolismo
9.
Regul Toxicol Pharmacol ; 71(3): 491-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25724632

RESUMO

Codonopsis lanceolata is a perennial plant that has been used as a food and in traditional medicine for the treatment of cough, bronchitis, and inflammation in East Asia including Korea, Japan, and China. However, information regarding its toxicity is limited. Therefore, we performed a safety evaluation of aqueous C. lanceolata root extract (CLE) in Sprague-Dawley rats. Assessment of acute toxicity revealed that CLE did not influence mortality, clinical appearance, body weight gain, or necropsy findings at a dose of 5000 mg/kg body weight. In the subchronic oral toxicity, data revealed that several significant alteration in food consumption, water consumption, protein excretion, WBCs levels, TGs, BUN levels, and the absolute and relative weights in the liver, spleen and lungs. However, these changes were transient and were not considered treatment related because they showed no apparent dose dependent. These results suggest that CLE (1250, 2500, and 5000 mg/kg body weight/day) administered orally does not cause acute or subchronic toxicity to male or female rats. The 50% lethal dose (LD50) of CLE was determined to be greater than 5000 mg/kg.


Assuntos
Codonopsis , Extratos Vegetais/toxicidade , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica , Administração Oral , Animais , Biomarcadores/sangue , Biomarcadores/urina , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Dose Letal Mediana , Masculino , Tamanho do Órgão/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/administração & dosagem , Raízes de Plantas , Plantas Medicinais , Proteinúria/induzido quimicamente , Proteinúria/urina , Ratos Sprague-Dawley , Medição de Risco , Fatores de Tempo , Testes de Toxicidade Aguda/métodos , Testes de Toxicidade Crônica/métodos
10.
Molecules ; 20(7): 13281-95, 2015 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-26205054

RESUMO

The antioxidant activity and chlorogenic acid and caffeic acid contents were investigated from different parts of Acanthopanax senticosus and A. koreanum. Antioxidant activity was assessed by various in vitro assays such as DPPH, ABTS, FRAP, reducing power assays and ORAC, and the chlorogenic acid and caffeic acid were validated by HPLC chromatography. Among the various extracts, the fruit extracts of A. senticosus and A. koreanum exhibited strongest antioxidant activities including ABTS, FRAP, reducing power and ORAC, however, strongest DPPH radical scavenging activity was observed from the leaf extract of A. senticosus. In addition, the antioxidant activities of various extracts were correlated with total phenolic and proanthocyanidin contents. The major phenolic contents from various parts of these plants observed that leaf extract of A. senticosus expressed higher levels of chlorogenic acid (14.86 mg/dry weigh g) and caffeic acid (3.09 mg/dry weigh g) than other parts. Therefore, these results suggest that the leaf of A. senticosus may be an excellent natural source for functional foods and pharmaceutical agents, and the validated method was useful for the quality control of A. senticosus.


Assuntos
Antioxidantes/química , Antioxidantes/isolamento & purificação , Eleutherococcus/química , Extratos Vegetais/química
11.
Molecules ; 19(6): 7138-51, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24886940

RESUMO

Cirsium setidens is a wild perennial plant species found in Korea that may have anti-oxidative, anti-adipogenic, and hepatoprotective activities. However, details of the toxicology of C. setidens remain unknown. This study was performed to evaluate the toxicological effects of an acute administration and 4-week repeated dosing of a C. setidens extract in Sprague-Dawley rats to ensure the safe use of this extract. C. setidens (1250, 2500, and 5000 mg/kg body weight/day) did not induce significant toxicological changes in groups matched by gender with respect to mortality, clinical signs, body weight, urinalysis, ophthalmoscopy, necropsy findings, hematology, and histopathology. Therefore, this study demonstrates that acute administration and 4-week repeated dosing of C. setidens extract orally using this administration protocol is safe.


Assuntos
Cirsium/química , Extratos Vegetais/toxicidade , Administração Oral , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Masculino , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Ratos , Ratos Sprague-Dawley
12.
Food Chem ; 441: 138363, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38199100

RESUMO

The optimization screening methods for total ergot alkaloids in wheat extracts involve transforming them into a single compound, which is then analyzed via high-resolution Orbitrap mass spectrometry (Orbitrap MS). Orbitrap MS provides highly sensitive and accurate mass measurements, enhancing the selectivity and sensitivity of the analysis. Various hydrolysis and reduction methods have been investigated, and the use of superhydrides has emerged as the most effective method for transforming ergopeptine alkaloids. This study also focused on the epimerization of ergot alkaloids, particularly the differences between R- and S-epimers and their impact on the mass spectra. We validated our method by assessing the linearity, sensitivity, recovery, matrix effects, repeatability, and stability. The limits of detection and quantitation were set at 0.43 and 1.30 µg LSA/kg wheat, respectively. The proposed method offers a robust analytical approach for screening and quantifying total ergot alkaloids in wheat samples, addressing important concerns about their presence in food and feed.


Assuntos
Alcaloides de Claviceps , Alcaloides de Claviceps/análise , Alcaloides de Claviceps/química , Farinha/análise , Triticum/química , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas , Contaminação de Alimentos/análise
13.
Molecules ; 18(10): 12937-50, 2013 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-24141244

RESUMO

Wild herbs, which are edible plants that grow in mountainous areas, have diverse biological effects such as anti-obesity and anti-cancer activities. The aim of this study was to evaluate the total phenolic and flavonoid contents as well as the antioxidant activity of methanol extracts of Aster scaber, Ligularia fischeri, Kalopanax pictus, Codonopsis lanceolata, and Cirsium setidens and to assess their effects on lipid accumulation and reactive oxygen species (ROS) production during adipogenesis of 3T3-L1 cells. The results revealed that among the five studied wild herb extracts, Ligularia fischeri showed the highest total phenolic contents (215.8 ± 14.2 mg GAE/g) and Aster scaber showed the highest total flavonoid content (103.9 ± 3.4 mg RE/g). Furthermore, Aster scaber and Ligularia fischeri extracts showed higher antioxidant activity than the other wild herbs. Regarding anti-adipogenic activity, the Cirsium setidens extract significantly inhibited lipid accumulation (~80%) and ROS production (~50%) during adipogenesis of 3T3-L1 cells compared with control cells. These results suggest that wild herbs could be used for the development of functional foods as well as health promoting and pharmaceutical agents.


Assuntos
Adipogenia/efeitos dos fármacos , Asteraceae/química , Sequestradores de Radicais Livres/farmacologia , Extratos Vegetais/farmacologia , Células 3T3-L1 , Animais , Benzotiazóis/química , Compostos de Bifenilo/química , Sobrevivência Celular/efeitos dos fármacos , Flavonoides/química , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Radicais Livres/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Camundongos , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Picratos/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo , República da Coreia , Ácidos Sulfônicos/química
14.
J Rheum Dis ; 30(4): 272-277, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37736588

RESUMO

Multisystem inflammatory syndrome in children (MIS-C) is a serious post-infectious complication of COVID-19 characterized by hyperinflammation and multi-organ dysfunction including shock. Shock is also seen in a severe form of Kawasaki disease (KD) called KD shock syndrome (KDSS). Here, we present one MIS-C and one KDSS case and compare similarities and differences between them. Both MIS-C (case 1) and KDSS (case 2) showed hyperinflammation, KD-related features, gastrointestinal problems, hypotension, and coagulopathy. The extent of systemic inflammation and organ dysfunction was more severe in KDSS than in MIS-C. Case 1 was diagnosed as MIS-C because SARS-CoV-2 was confirmed, and case 2 was diagnosed as KDSS because no pathogen was identified in microbiological studies. We believe that the most important difference between MIS-C and KDSS was whether SARS-CoV-2 was identified as an infectious trigger. Organ dysfunction is a hallmark of MIS-C and KDSS, but not KD, so MIS-C shares more clinical phenotypes with KDSS than with KD. Comparison of MIS-C and KDSS will be an interesting and important topic in the field of KD-like hyperinflammatory disease research.

15.
Adv Sci (Weinh) ; 10(21): e2301603, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37166033

RESUMO

Perovskite solar cells (PeSCs) using FAPbI3 perovskite films often exhibit unfavorable phase transitions and defect-induced nonradiative interfacial recombination, resulting in considerable energy loss and impairing the performance of PeSCs in terms of efficiency, stability, and hysteresis. In this work, a facile interface engineering strategy to control the surface structure and energy-level alignment of perovskite films by tailoring the interface between the FAPbI3 film and hole-transporting layer using 4-hydroxypicolinic acid (4HPA) is reported. According to density functional theory studies, 4HPA has prominent electron delocalization distribution properties that enable it to anchor to the perovskite film surface and facilitate charge transfer at the interface. By enabling multiple bonding interactions with the perovskite layer, including hydrogen bonds, PbO, and PbN dative bonds, 4HPA passivation significantly reduces the trap density and efficiently suppresses nonradiative recombination. The obtained perovskite films exhibit superior optoelectronic properties with improved crystallinity, pure α-phase FAPbI3 , and favorable energy band bending. Following this strategy, 4HPA post-treatment PeSCs achieve a champion power conversion efficiency of 23.28% in 0.12 cm2 cells and 19.26% in 36 cm2 modules with excellent environmental and thermal stabilities.

16.
Food Sci Biotechnol ; 31(2): 165-174, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35186347

RESUMO

This study was designed to determine the residual trichothecene mycotoxins in cereal samples. The optimal solvent for extraction was 84% (v/v) aqueous acetonitrile with 1% (v/v) formic acid. The best performing clean-up method was dispersive-solid phase with a mixture octadecyl silica and primary-secondary amine. The recoveries for the studied mycotoxins ranged from 83.3 to 92.8%. The methodology was successfully applied for monitoring 100 cereal samples obtained from a Korean market. The bean sample were found to be co-contamination with deoxynivalenol and HT-2 toxin. Deoxynivalenol possessed the highest detection freauency (4/100) and amount (727.38 µg/kg) among the trichothecene mycotoxins. The hazard index was less than 1.0 for all the observed mycotoxins in all cereal samples except one white rice sample (1.2681). This results indicated that periodic risk assessments of trichothecene mycotoxin through cereal intake are necessary for the health and safety.

17.
Food Chem ; 382: 132313, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35158273

RESUMO

The practice of abusing antibiotics to improve livestock growth poses a threat to food safety. To prevent and regulate this, accurate monitoring of residual veterinary drugs (VDs) is required. A method based on QuEChERS with dispersive solid-phase extraction for the determination of multi-class VDs was investigated using selected product ions under optimized multiple reaction monitoring conditions. During the clean-up procedure, chitosan, octadecyl silica, primary-secondary amine, and enhanced matrix removal (EMR)-lipid were evaluated for simultaneous analysis of multi-class VDs in beef matrix. The EMR sorbent was most advantageous (113/115) compared to others, and showed a satisfactory recovery range (70.7-117.9%) except cefquinome (67.3%) and cefalonium (69.8%). This methodology can be used to detect oxolinic acid and ractopamine (27.4% and 88.0% of maximum residue limit, respectively) in real beef samples. We thus study propose a simple and fast analytical method for multi-class VDs for the future health of humans and animals.


Assuntos
Drogas Veterinárias , Animais , Bovinos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Drogas Veterinárias/análise
18.
Children (Basel) ; 9(10)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36291524

RESUMO

Recognition of macrophage activation syndrome (MAS) in patients with refractory Kawasaki disease (KD) can be challenging. This study aimed to investigate the incidence of MAS in patients with refractory KD and to compare the characteristics of refractory KD and MAS. Medical records of 468 patients diagnosed with KD from January 2010 to December 2019 were retrospectively reviewed. Of the 468 KD patients, 63 were enrolled in the study as a refractory KD group (n = 59) and an MAS group (n = 4). The incidence of MAS was 0.8% (4/468) in patients with KD and 6.3% (4/63) in patients with refractory KD. Compared to the refractory KD group, the MAS group had higher frequencies of incomplete KD, hepatosplenomegaly, third-line treatment, and MAS screening, and showed lower levels of albumin. No significant differences were found in other clinical and laboratory findings. In addition to four patients with MAS, five patients with refractory KD who received third-line treatment showed severe systemic inflammation and organ dysfunction, but only one in five patients underwent MAS screening, including ferritin levels. In conclusion, given the relatively high incidence of MAS in children with refractory KD and the similar phenotype between refractory KD and MAS, we propose that MAS screening should be included in routine laboratory tests for refractory KD.

19.
Foods ; 11(3)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35159566

RESUMO

Pesticides which are diluted and sprayed according to the pre-harvest interval (PHI) are generally decomposed and lost through various factors and pathways, and the leftover pesticides are known as residual pesticides. This study aims to determine the dissipation of residual amounts of dinotefuran, fluazinam, indoxacarb, and thiacloprid in persimmon and the changes in the concentration of various processing products. Pesticide spraying is performed in accordance with the GAP (good agricultue practice) of Korea, and the processed products are manufactured using a conventional method after removing the skin of persimmons. The modified QuEchERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method and an optimized method using LC-MS/MS (liquid chromatography mass spectrometry) is implemented to analyze the residual pesticides. The linearity, recovery, and LOQ (limit of quantitation) are presented to verify the analysis method. The amount of residual pesticides tested decreases significantly in a time-dependent manner, regardless of the minimal dilution effect present due to growth. The residual concentration does not vary significantly during the processing stage despite the removal of the systemic pesticides, dinotefuran and thiacloprid. The residues of non-systemic pesticides, fluazinam and indoxacarb, are typically removed by the peeling removal and processing methods. The reduction factor of dinotefuran, whose residual concentration is increased, is less than 1, and the absolute amount of pesticides is decreased through processing. The results of this study can be used as the scientific basis data to ensure the safety of residual pesticides in processed products in the future.

20.
Food Sci Biotechnol ; 30(10): 1393-1401, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34691806

RESUMO

The risk of foodborne illnesses caused by pathogens could be increased in fresh-cut fruit products owing to contamination during processing. Therefore, this study was conducted to investigate the microbiological quality and safety of commercial fresh-cut fruit products in Korea. Additionally, the growth of Listeria monocytogenes in selected fresh-cut fruits was evaluated, and their growth curves were analyzed using predictive growth modeling. The mean count of total aerobic bacteria, coliforms, and yeast/mold was 3.67±1.73 log10 CFU/g, 1.54±1.01 log10 CFU/g, and 3.81±1.51 log10 CFU/g, respectively. Escherichia coli, Staphylococcus aureus, Escherichia coli O157:H7, L. monocytogenes, Salmonella spp., and Cyclospora spp. were not detected in any of the tested samples. Only Bacillus cereus was detected in a few samples at the mean level of 1.72±0.13 log10 CFU/g. The growth of L. monocytogenes varied depending on the type of fruit; they grew well in non-acidic fresh-cut fruit products during storage at 10 °C.

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