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1.
Shokuhin Eiseigaku Zasshi ; 65(1): 20-23, 2024.
Artigo em Japonês | MEDLINE | ID: mdl-38432898

RESUMO

In this study, a public seminar on risk communication methods was conducted to raise awareness and disseminate accurate knowledge about residual pesticides to consumers. Additionally, surveys on consumer awareness were conducted on the attendees before and after the seminar to evaluate its effectiveness. Responses were obtained from 84 participants. The paired t-test was used to analyze the changes in awareness before and after the seminar. The results showed significant improvements in "trust in the government" and "understanding of residual pesticides." Furthermore, step-wise multiple regression analysis was performed to explore the factors influencing satisfaction with the risk communication seminar, and the item "understanding of the safety of residual pesticides in food" was extracted. Understanding food safety is a crucial concern in daily life for consumers. To enable consumers to have an accurate understanding of food risks and make appropriate judgments, it is essential to continue implementing risk communication and conveying information about food safety and security in the future.


Assuntos
Praguicidas , Humanos , Comunicação , Inocuidade dos Alimentos
2.
Shokuhin Eiseigaku Zasshi ; 64(4): 123-129, 2023.
Artigo em Japonês | MEDLINE | ID: mdl-37673601

RESUMO

Gibberellic acid (GA3) is commonly used as a plant growth regulator in many food crops owing to its essential signaling functions during plant growth and development. In Japan, a threshold for administrative action for GA3 content of 0.3 mg/kg applies in produce in which maximum residue limits have not been established. Although the threshold is based on previous studies, the GA3 concentrations in individual foods are still unknown. Thus, we surveyed the concentrations of GA3 in banana, cherry, and kiwi fruit on the Japanese market. We developed and validated a method for the analysis of GA3 using solid-phase extraction and LC-MS/MS in accordance with accepted criteria of trueness, repeatability, and selectivity. The limits of detection and of quantification were determined as 0.005 and 0.05 mg/kg, respectively, in all fruits. Concentrations of GA3 did not exceed 0.3 mg/kg regardless of ripeness, suggesting the reasonability of the current regulation of GA3 in banana, cherry, and kiwi fruit. These findings can support prompt administrative action on these fruits, contributing to the regulation of GA3 in Japan.


Assuntos
Frutas , Musa , Cromatografia Líquida , Espectrometria de Massas em Tandem , Produtos Agrícolas
3.
Biomed Chromatogr ; 37(10): e5697, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37394894

RESUMO

Cannabidiol (CBD) oil products are available in Japan as cosmetics, fragrances, food and items. Herein, quality testing of cannabinoid profiling in CBD oil products and the evaluation of possible residual tetrahydrocannabinol (THC) in these products using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was conducted. A simple, sensitive, and selective LC-MS/MS assay (electrospray positive ion mode) was employed for the simultaneous quantification of eight cannabinoids. This quantification with three different oil samples showed that accuracy rates ranged from 87.7 to 106.9% (RSD > 3.5%). Furthermore, the quantification limit of THC is 0.001 mg/g of CBD oil products for suitable levels lower than the regulatory value. Notably, this method was used to evaluate CBD oil products from the Japanese market. Additionally, we investigated the THC conversion in CBD oil products at a high temperature (70°C) which has a minor effect on CBD stability in oil products with additives. Herein, the developed LC-MS/MS assay is applied to monitor the quality of CBD, trace THC and other components in CBD oil products.


Assuntos
Canabidiol , Canabinoides , Canabidiol/análise , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Temperatura , Canabinoides/análise , Dronabinol
4.
J Chromatogr A ; 1694: 463901, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36889118

RESUMO

Isolation of valuable chemicals is an important process in reagent manufacturing for the pharmaceutical and food science industries. This process is traditionally time-consuming, expensive, and consumes vast amounts of organic solvents. Considering green chemistry and sustainability concerns, we sought to develop a sustainable chromatographic purification methodology for obtaining antibiotics by focusing on the reduction of organic solvent waste generation. Milbemectin (mixture of milbemycin A3 and milbemycin A4) was successfully purified using high-speed countercurrent chromatography (HSCCC) and pure fractions (>98% purity, HPLC) could be identified using the organic solvent fee atmospheric pressure solid analysis probe mass spectrometry (ASAP-MS). The organic solvents required for HSCCC could be redistilled and recycled for continued HSCCC purification, thus reducing the consumption of organic solvent (n-hexane/ethyl acetate) by 80+%. Optimization of the two-phase solvent system (n-hexane/ethyl acetate/methanol/water, 9/1/7/3, v/v/v/v) for HSCCC was assisted computationally, thereby reducing solvent waste from an experimental determination. Our proposal application of HSCCC and offline ASAP-MS provides proof of concept for a sustainable, preparative scale, chromatographic purification methodology for obtaining antibiotics in high purity.


Assuntos
Antibacterianos , Distribuição Contracorrente , Distribuição Contracorrente/métodos , Espectrometria de Massas , Solventes/química , Cromatografia Líquida de Alta Pressão/métodos
5.
Chem Pharm Bull (Tokyo) ; 70(1): 12-18, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34980727

RESUMO

Due to the globalization of food production and distribution, the food chain has become increasingly complex, making it more difficult to evaluate unexpected food changes. Therefore, establishing sensitive, robust, and cost-effective analytical platforms to efficiently extract and analyze the food-chemicals in complex food matrices is essential, however, challenging. LC/MS-based metabolomics is the key to obtain a broad overview of human metabolism and understand novel food science. Various metabolomics approaches (e.g., targeted and/or untargeted) and sample preparation techniques in food analysis have their own advantages and limitations. Selecting an analytical platform that matches the characteristics of the analytes is important for food analysis. This review highlighted the recent trends and applications of metabolomics based on "foodomics" by LC-MS and provides the perspectives and insights into the methodology and various sample preparation techniques in food analysis.


Assuntos
Análise de Alimentos , Metabolômica , Cromatografia Líquida , Humanos , Espectrometria de Massas
6.
Artigo em Inglês | MEDLINE | ID: mdl-33455529

RESUMO

Progesterone (P4) is contained naturally in animal tissue, and it is also used as a veterinary drug in cattle for treatment purposes. To assess the risk from P4 residues in beef derived from treated cattle, it is essential to quantify the P4 contained naturally in cattle tissue (endogenous P4). Therefore, we performed a method validation for the quantification of endogenous P4 (method quantification limit = 0.06 ng g-1) by using isotope-labelled P4s, and investigated the P4 contents in Japanese beef (n= 112; 0.07 to 121 ng g-1). The P4 contents in cattle muscle ranged from 0.07 to 54.3 ng g-1 in males, and from 0.27 to 121 ng g-1 in females. Our investigation also indicated that the developed method using both 13C- and deuterium-labelled P4 standards could be used to certify the recovery of P4 from cattle muscle containing various amounts of intramuscular fat, and enabled the determination of the P4 content in all Japanese beef samples that exceeded the method quantification limit.


Assuntos
Progesterona/análise , Carne Vermelha/análise , Animais , Isótopos de Carbono/química , Bovinos , Cromatografia Líquida de Alta Pressão , Deutério/química , Feminino , Inocuidade dos Alimentos , Marcação por Isótopo , Limite de Detecção , Masculino , Padrões de Referência , Espectrometria de Massas em Tandem
7.
J Alzheimers Dis ; 53(4): 1433-41, 2016 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-27392863

RESUMO

Exosomes are small extracellular vesicles secreted by variety of cell types such as neurons, astrocytes, and oligodendrocytes. It is suggested that exosomes play essential role in the maintenance of the neuronal functions and also in the clearance of amyloid-ß (Aß) from the brain. Aß is well known to cause neuronal cell death, whereas little is known about its effect on astrocytes. In this study, we examined the effect of Aß on release of exosomes from astrocytes in culture. We analyzed release of exosomes and apoE, both of which are known to remove/clear Aß from the brain, in the culture medium of astrocytes. We found that exosome and apoE-HDL were successfully separated by density gradient ultracentrifugation demonstrated by distribution of their specific markers, flotillin and HSP90, and cholesterol, and morphological analysis using electron microscopy. Exosome release was significantly reduced by Aß1-42 treatment in cultured astrocytes accompanied by an increased JNK phosphorylation. Whereas, apoE-HDL release remained unchanged. A JNK inhibitor restored the decreased levels of exosome release induced by Aß treatment to levels similar to those of control, suggesting that Aß1-42 inhibits exosome release via stimulation of JNK signal pathway. Because exosomes are shown to remove Aß in the brain, our findings suggest that increased Aß levels in the brain may impair the exosome-mediated Aß clearance pathway.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Astrócitos/enzimologia , Astrócitos/metabolismo , Exossomos/metabolismo , MAP Quinase Quinase 4/metabolismo , Fragmentos de Peptídeos/metabolismo , Animais , Antracenos/farmacologia , Apolipoproteínas E/metabolismo , Astrócitos/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/enzimologia , Córtex Cerebral/metabolismo , Colesterol/metabolismo , Meios de Cultura , Exossomos/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , MAP Quinase Quinase 4/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley
8.
Toxicol Appl Pharmacol ; 279(3): 331-337, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24998969

RESUMO

Organophosphate (OP) compounds as anticholinesterase agents may secondarily act on diverse serine hydrolase targets, revealing unfavorable physiological effects including male reproductive toxicity. The present investigation proposes that fenitrothion (FNT, a major OP compound) acts on the endocannabinoid signaling system in male reproductive organs, thereby leading to spermatotoxicity (sperm deformity, underdevelopment, and reduced motility) in rats. FNT oxon (bioactive metabolite of FNT) preferentially inhibited the fatty acid amide hydrolase (FAAH), an endocannabinoid anandamide (AEA) hydrolase, in the rat cellular membrane preparation from the testis in vitro. Subsequently, male Wistar rats were treated orally with 5 or 10mg/kg FNT for 9 weeks and the subchronic exposure unambiguously deteriorated sperm motility and morphology. The activity-based protein profiling analysis with a phosphonofluoridate fluorescent probe revealed that FAAH was selectively inhibited among the FNT-treated cellular membrane proteome in testis. Intriguingly, testicular AEA (endogenous substrate of FAAH) levels were elevated along with the FAAH inhibition caused by the subchronic exposure. More importantly, linear regression analyses for the FNT-elicited spermatotoxicity reveal a good correlation between the testicular FAAH activity and morphological indices or sperm motility. Accordingly, the present study proposes that the FNT-elicited spermatotoxicity appears to be related to inhibition of FAAH leading to overstimulation of the endocannabinoid signaling system, which plays crucial roles in spermatogenesis and sperm motility acquirement.


Assuntos
Endocanabinoides/fisiologia , Fenitrotion/toxicidade , Inseticidas/toxicidade , Espermatozoides/efeitos dos fármacos , Trifosfato de Adenosina/metabolismo , Amidoidrolases/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Epididimo/citologia , Epididimo/efeitos dos fármacos , Hormônios Esteroides Gonadais/metabolismo , Masculino , Espectrometria de Massas , Síndromes Neurotóxicas/patologia , Síndromes Neurotóxicas/psicologia , Ratos , Ratos Wistar , Contagem de Espermatozoides , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/ultraestrutura , Testículo/efeitos dos fármacos , Testículo/enzimologia , Testículo/metabolismo
9.
J Sep Sci ; 31(22): 3871-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19065618

RESUMO

A highly sensitive and selective method using LC-ESI-MS/MS and tandem-SPE was developed to detect trace amounts of avoparcin (AV) antibiotics in animal tissues and milk. Data acquisition using MS/MS was achieved by applying multiple reaction monitoring of the product ions of [M + 3H](3+) and the major product ions of AV-alpha and -beta at m/z 637 --> 86/113/130 and m/z 649 --> 86/113/130 in ESI(+) mode. The calculated instrumental LODs were 3 ng/mL. The sample preparation was described that the extraction using 5% TFA and the tandem-SPE with an ion-exchange (SAX) and InertSep C18-A cartridge clean-up enable us to determine AV in samples. Ion suppression was decreased by concentration rates of each sample solution. These SPE concentration levels could be used to detect quantities of 5 ppb (milk), 10 ppb (beef), and 25 ppb (chicken muscle and liver). The matrix matching calibration graphs obtained for both AV-alpha (r >0.996) and -beta (r >0.998) from animal tissues and milk were linear over the calibration ranges. AV recovery from samples was higher than 73.3% and the RSD was less than 12.0% (n = 5).


Assuntos
Antibacterianos/análise , Cromatografia Líquida/métodos , Glicopeptídeos/análise , Leite/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Animais
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