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1.
Shokuhin Eiseigaku Zasshi ; 64(4): 145-153, 2023.
Artigo em Japonês | MEDLINE | ID: mdl-37673604

RESUMO

We determined the fifteen types of plasticizers, including four kinds of phthalic acid esters (PAEs) used in 220 polyvinyl chloride (PVC) toys on Japanese market from 2019 to 2020. Three kinds of previously undetected types of PAEs were also detected, but not identified in this study. Di (2-ethylhexyl) terephthalate (DEHTP) was the highest detection rate in 209 soft PVC toys out of 220 toys, with 71.2% for designated toys and 88.9% for not-designated toys, respectively, showing a gradual increase from the previous reports in 2009 and 2014. On the other hand, the usages of o-acetyl tributyl citrate and adipic acid esters decreased, but the six types of PAEs prohibited to use for the designated toys in Japan were not detected in them, the usage of diisobutyl phthalate were increased. In contrast, four types of PAEs were detected in not-designated toys. Among them, the detection ratio of di (2-ethyhexyl) phthalate decreased to about 1/10. The content levels of plasticizers in per each sample were continued to keep low level from the report five years ago. These results showed that the main plasticizer used in PVC toys is DEHTP, and that the usage of other plasticizers was decreased.


Assuntos
Plastificantes , Cloreto de Polivinila , Ésteres , Japão
2.
Shokuhin Eiseigaku Zasshi ; 64(4): 154-160, 2023.
Artigo em Japonês | MEDLINE | ID: mdl-37673605

RESUMO

An inter-laboratory study involving 24 laboratories was conducted to validate the modified analytical method for the migration solution of heptane for the determination of bisphenol A migrating from polycarbonate food processing materials. In this study, two concentrations of samples were blindly coded. Each laboratory determined the analyte (bisphenol A, phenol and p-tert-butylphenol) concentration in each sample according to the established protocol. The obtained values were analyzed statistically using internationally accepted guidelines. Horwitz ratios were calculated based on the reproducibility relative standard deviation (RSDR), which was estimated from the inter-laboratory study, and predicted RSDR, which was calculated using the Horwitz/Thompson equation. Horwitz ratios of the two samples ranged from 0.15 to 0.37 for the three compounds, meeting the performance criteria of less than 2 set by the Codex Alimentarius for analytical method approval. These results showed that this modified analytical method shows good performance as an analytical method for the migration solution of heptane.


Assuntos
Heptanos , Fenóis , Reprodutibilidade dos Testes
3.
Shokuhin Eiseigaku Zasshi ; 64(3): 111-115, 2023.
Artigo em Japonês | MEDLINE | ID: mdl-37380481

RESUMO

A validation study was performed on the modified analytical method for the migration solution of heptane, 20% ethanol and 4% acetic acid for the determination of bisphenol A migrating from polycarbonate food apparatuses, containers, and packaging. The analytes for the method were bisphenol A, phenol and p-tert-butylphenol. The repeatability, within-laboratory reproducibility and trueness of the method was estimated in the range of 0.2-1.8%, 0.4-2.6% and 95-102% respectively. These results showed that the method is useful as an analytical method for the migration solution of heptane, 20% ethanol and 4% acetic acid. Furthermore, the applicability of the determination methods with a fluorescence detector was verified. As a result of the validation study, the repeatability, within-laboratory reproducibility and trueness of the method was estimated in the range of 0.1-2.9%, 0.2-3.1% and 94-101% respectively. It was confirmed that the measurement with a fluorescence detector is also available.


Assuntos
Ácido Acético , Fenóis , Reprodutibilidade dos Testes , Etanol , Heptanos
4.
Shokuhin Eiseigaku Zasshi ; 64(2): 69-77, 2023.
Artigo em Japonês | MEDLINE | ID: mdl-37211388

RESUMO

The growth and gas production test for Escherichia coli in the microbiological examination of food additives is stipulated in the ninth edition of Japan's Specifications and Standards for Food Additives (JSFA) and described as a part of the "Confirmation Test for Escherichia coli" in "Microbial Limit Tests" in the same manuscript. The growth and gas production test for E. coli indicated that the positive or negative of "gas production and/or turbidity" in EC broth should be confirmed after incubating at 45.5±0.2℃ for 24±2 h. If both gas production and turbidity are negative, the culture is additionally incubated up to 48±2 h to determine E. coli contamination. The internationally referenced Bacteriological Analytical Manual of the U.S. FDA had revised the incubation temperature in tests for coliforms and E. coli from 45.5±0.2℃ to 44.5±0.2℃ in 2017. Therefore, we conducted research in anticipation of this temperature change being reflected in the microbiological examination of the JSFA. We used seven EC broth products and six food additives across eight products that are available in Japan in order to compare the growth and gas production at temperatures of 45.5±0.2℃ and 44.5±0.2℃ of E. coli NBRC 3972, which is designated as the test strain in JSFA. Both with/without food additives, the number of EC broth products in which medium turbidity and gas production by the strain were positive in three out of three tubes at all test times was greater at 44.5±0.2℃ than at 45.5±0.2℃. These results suggest that the growth and gas production test for E. coli could be more appropriately conducted by incubation at 44.5±0.2℃ in the "Confirmation Test for Escherichia coli" for E. coli in the JSFA in comparison to 45.5±0.2℃. Furthermore, there were differences in the growth and gas production of E. coli NBRC 3972 depending on the EC broth product used. Therefore, the importance of "Media growth promotion test" and "Method suitability test" in the ninth edition of the JSFA should be emphasized.


Assuntos
Escherichia coli , Microbiologia de Alimentos , Meios de Cultura , Japão
5.
Shokuhin Eiseigaku Zasshi ; 64(2): 78-88, 2023.
Artigo em Japonês | MEDLINE | ID: mdl-37211389

RESUMO

The official specifications for food additives from natural sources list the species according to their scientific and Japanese names, thereby providing a unique identifier for the species. This helps to prevent the use of nonprescribed species, which might cause unexpected or unintended health hazards. However, there are cases in which the names of the source species listed in the official specifications differ from the accepted scientific names based on the latest taxonomic research. In this paper, we argue that it is more important to define scientific and Japanese names with an emphasis on traceability in order to control the range of food additive ingredients in a rational and sustainable manner. Therefore, we proposed a method for ensuring traceability as well as a specific notation procedure for scientific and Japanese names. Using this method, we examined the source species for three food additives. In some cases, the range of sources species expanded with the change in scientific names. Ensuring traceability is extremely important, but it is also necessary to confirm whether unexpected species are included when names are changed.


Assuntos
Aditivos Alimentares , Aditivos Alimentares/normas , Japão
6.
J Epidemiol ; 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37211396

RESUMO

BACKGROUND: Glomerular hyperfiltration has been reported to be associated with adverse renal outcomes in general population. It is not known whether drinking pattern is associated with the risk of glomerular hyperfiltration in healthy individuals. METHODS: We prospectively followed middle-aged 8,640 Japanese men with normal renal function, no proteinuria, no diabetes, and no use of antihypertensive medications at entry. Data on alcohol consumption were gathered by questionnaire. Glomerular hyperfiltration was defined as estimated glomerular filtration rate (eGFR) ≥117 mL/min/1.73 m2, which was the upper 2.5th percentile value of eGFR in the entire cohort. RESULTS: During 46,186 person-years of follow-up, 330 men developed glomerular hyperfiltration. In a multivariate model, for men who consumed alcohol on 1-3 days per week, alcohol consumption of ≥69.1g ethanol/drinking day was significantly associated with the risk of glomerular hyperfiltration (hazard ratio (HR), 2.37 (95% CI, 1.18-4.74)) compared with non-drinkers. For those who consumed alcohol on 4-7 days per week, higher alcohol consumption per drinking day was associated with a higher risk of glomerular hyperfiltration: the HRs (95% CI) for alcohol consumption of 46.1-69.0, and ≥69.1 g ethanol/drinking day were 1.55 (1.01-2.38), and 1.78 (1.02-3.12), respectively. CONCLUSIONS: For high drinking frequency per week, more alcohol intake per drinking day was associated with an increased risk of glomerular hyperfiltration, while for low drinking frequency per week, only very high alcohol intake per drinking day was associated with an increased risk of glomerular hyperfiltration in middle-aged Japanese men.

7.
Shokuhin Eiseigaku Zasshi ; 64(1): 47-52, 2023.
Artigo em Japonês | MEDLINE | ID: mdl-36858591

RESUMO

A simple and reliable analytical method has been developed for the determination of pantothenic acid in food. For the high-protein food, 20 mL of water was added to 2 g of sample, and after homogenization extraction, 1 mL of 15% zinc sulfate solution was added, mixed well, centrifuged, and the supernatant was filtered to make the test solution. For the low-protein food, 20 mL of 1% formic acid solution was added to 2 g of sample, homogenized, extracted, centrifuged, and the supernatant was filtered to make the test solution. The HPLC separation was carried out on a L-column2 ODS column with 0.02 mol/L phosphate solution (pH 3.0)- acetonitrile (95 : 5) as the mobile phase, and detected at 200 nm. The LC-MS/MS conditions were L-column2 ODS as the separation column, 5 mmol/L ammonium formate (containing 0.01% formic acid)-methanol (85 : 15) as the mobile phase, and multiple reaction monitoring (MRM) was used for detection. The recoveries of pantothenic acid in milk powder and nutritional food products were more than 88% with high precision. As a result of analyzing commetrcially available foods labeled as containing pantothenic acid, analytical values almost identical to the labeled values were obtained, and a high correlation was observed between the values obtained by HPLC and LC-MS/MS.


Assuntos
Ácido Pantotênico , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida
8.
Artigo em Inglês | MEDLINE | ID: mdl-36669121

RESUMO

To estimate the daily intake of food additives by young children aged 1-6 years in Japan, an intake survey was conducted in 2018 using the market basket method for food additives, including twelve types of colourants, three kinds of preservatives, three kinds of sweeteners and two kinds of food manufacturing agents. A list of the daily consumption of processed foods was prepared based on a special survey (MHLW 2011) and used for the estimation. The results of the survey showed that the food additives with the highest daily intake were phosphorus compounds (phosphoric acid and its salts; 11.2 mg/kg bw/day, expressed as phosphorus), followed by propylene glycol (0.80 mg/kg bw/day). The daily intake of other food additives ranged from 0 to 0.20 mg/kg bw/day. The estimated daily intake of each food additives by young children was compared with the acceptable daily intake (ADI) or maximum tolerable daily intake (MTDI). The highest ratio of the estimated daily intake to ADI was 3.2% for propylene glycol, whereas the ratios of the estimated daily intake to ADI for colourants, preservatives and sweeteners ranged from 0 to 1.1% (benzoic acid). The ratio of the estimated daily intake to MTDI for phosphorus compounds was 16%.


Assuntos
Dieta , População do Leste Asiático , Aditivos Alimentares , Criança , Pré-Escolar , Humanos , Propilenoglicol , Edulcorantes , Lactente , Compostos de Fósforo
9.
Shokuhin Eiseigaku Zasshi ; 64(6): 240-245, 2023.
Artigo em Japonês | MEDLINE | ID: mdl-38171896

RESUMO

In general, nitrite in food is extracted under slightly alkaline conditions, deproteinized, and analyzed by a colorimetric method using color development by diazotization. However, depending on the sample, the sample solution may become cloudy and difficult to filter by the deproteinization treatment of the analytical method. Recently, an improved analytical method that solves these problems has been reported. Therefore, a validation study was performed on the improved analytical method was performed. The concentrations of sodium nitrite added to cod roe, fish sausage, and ham, which were not labeled with sodium nitrite, were set at the upper limits of the standards for use. We set the target values of 70-120% for trueness, less than 15% for intralaboratory reproducibility, and less than intralaboratory reproducibility for repeatability. As a result, the target values were met for the three samples verified: 88-92% for trueness, 2.0-3.0% for repeatability, and 3.2-4.3% for intralaboratory reproducibility. In addition, an interlaboratory study was conducted by eight institutes on the improved analytical method for nitrite. At each institution, sodium nitrite was added to the same three samples as in the validation study, at concentrations equivalent to twice the lower limit of quantification and the upper limit of the standards for use and analyzed in triplicate. The estimated trueness from the obtained analyses ranged from 82 to 95%, the repeatability ranged from 2.3 to 5.8%, and the inter-room reproducibility ranged from 3.5 to 11%. Thus, the improved analytical method could be useful for determining nitrite in foods.


Assuntos
Produtos da Carne , Nitrito de Sódio , Animais , Reprodutibilidade dos Testes , Produtos da Carne/análise , Colorimetria/métodos
10.
Shokuhin Eiseigaku Zasshi ; 63(2): 51-61, 2022.
Artigo em Japonês | MEDLINE | ID: mdl-35650029

RESUMO

Migration test of food utensils, containers, and packaging is an important test method for confirming the safety and their compliance to the standards. However, there is little report on inter-laboratory study which was performed to evaluate the entire migration test, including migration operations and quantification. An interlaboratory study was performed participating 22 laboratories using 8 types of model synthetic resin samples containing 10 substances with a wide range of Log Pow values to evaluate the accuracy of the entire migration test. As a result, most of HorRat (r) values met the target criteria (0.3

Assuntos
Contaminação de Alimentos , Plásticos , Contaminação de Alimentos/análise , Embalagem de Alimentos , Laboratórios
11.
Shokuhin Eiseigaku Zasshi ; 63(2): 97-103, 2022.
Artigo em Japonês | MEDLINE | ID: mdl-35650035

RESUMO

We modified a method for determining methanol content in detergents used in kitchens. Furthermore, an inter-laboratory study was conducted in 10 laboratories to validate the modified method. In this study, two concentrations of samples were blindly coded. Each laboratory determined the methanol content in each sample according to a protocol. The determined values were statistically analyzed according to an international harmonized guideline. HorRat values were calculated based on the reproducibility relative standard deviation (RSDR) which was estimated from the interlaboratory study, and predicted RSDR calculated from the Horwitz/Thompson equation. The HorRat values of the two samples were 0.8 and 1.8, meeting the performance criteria of less than 2 set by the Codex Alimentarius for analytical method approval. These results confirm that this modified analytical method shows good performance as an analytical method for determining methanol content in kitchen detergents.


Assuntos
Detergentes , Metanol , Laboratórios , Reprodutibilidade dos Testes
12.
Am J Nephrol ; 53(2-3): 191-198, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35139520

RESUMO

INTRODUCTION: Proteinuria is a risk factor for end-stage renal failure. However, it is not known whether body mass index (BMI) is prospectively associated with the risk of future developing proteinuria, taking into account transient proteinuria. METHODS: We enrolled 9,320 nondiabetic Japanese middle-aged men who had no proteinuria, an estimated glomerular filtration rate ≥60 mL/min/1.73 m2, no history of cancer, and no use of antihypertensive medications at baseline. "Any proteinuria" was defined as proteinuria detected for the first time during the follow-up period regardless of its frequency. "Persistent proteinuria" was defined as proteinuria that was detected at least twice consecutively at annual examinations and did not return to negative until the end of the follow-up. RESULTS: During the 11-year follow-up period, 1,972 cases of any proteinuria and 151 cases of persistent proteinuria were confirmed. Both lower and higher BMI were associated with the risk of any proteinuria. As for persistent proteinuria, in those with a BMI ≥20 kg/m2, higher BMI was associated with a higher risk of future persistent proteinuria. The association between BMI and the risk of persistent proteinuria was stronger than that between BMI and any proteinuria. In multiple-adjusted model, hazard ratios of persistent proteinuria for BMI <18.0, 18.0-19.9, 20.0-21.9, 22.0-23.9, 24.0-25.9, 26.0-27.9, and ≥28.0 kg/m2 were 1.52 (95% confidence interval 0.51-4.49), 1.07 (0.49-2.29), 1.00 (reference), 1.14 (0.64-2.01), 1.89 (1.09-3.27), 2.12 (1.15-3.93), and 3.85 (2.03-7.30), respectively. DISCUSSION/CONCLUSION: In those with a BMI ≥20 kg/m2, higher BMI was associated with a higher risk of future persistent proteinuria and any proteinuria. This relationship was stronger for persistent proteinuria than for any proteinuria.


Assuntos
Atenção à Saúde , Proteinúria , Índice de Massa Corporal , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteinúria/etiologia , Fatores de Risco
13.
Chem Pharm Bull (Tokyo) ; 70(1): 25-31, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34980729

RESUMO

We report on the recommendation of the simple and versatility of methylated reference (MR) to improve applications in the single reference (SR)-LC based on relative molar sensitivity (RMS). Three curcuminoids (Curs) such as curcumin, demethoxycurcumin and bisdemethoxycurcumin in turmeric products were determined using authentic standards and methylated curcumin. In addition, high-speed countercurrent chromatography (HSCCC) purification is necessary to separate Curs for indicating the RMS. For HSCCC separation, a biphasic solvent system was used to obtain these fractions, which were then subjected to 1H quantitative NMR to determine their contents in each test solution. Using these solutions, the RMS of Curs are calculated from slopes ratios of calibration curves (three ranges from 0-100 µmol/L, r2 > 0.998). The averaged RMS of Curs were 8.92 (relative standard deviation (RSD), 1.17%), 8.97 (2.18%), and 9.61 (0.77%), respectively. Cur concentrations in turmeric products can be determined using RMS, peak area, and MR content added in these samples. This proposed method, which is based on chemical methylation and the SR-LC assay has been successfully applied for the simple and reliable estimation of Curs in turmeric products.


Assuntos
Diarileptanoides/química , Cromatografia Líquida de Alta Pressão/normas , Metilação , Estrutura Molecular , Padrões de Referência
14.
Front Neurosci ; 15: 707345, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335177

RESUMO

BACKGROUND: The sympathetic arterial baroreflex is a closed-loop feedback system for stabilizing arterial pressure (AP). Identification of unique functions of the closed system in humans is a challenge. Here we propose an analytic and integrative framework for identifying a static operating point and open-loop gain to characterize sympathetic arterial baroreflex in humans. METHODS AND RESULTS: An equilibrium diagram with two crossing functions of mechanoneural (MN) and neuromechanical (NM) arcs was analyzed during graded tilt maneuvers in seven healthy subjects. AP and plasma norepinephrine level (PNE), as a surrogate for sympathetic nerve activity, and were recorded after vagal modulation of heart function was blocked by atropine. The MN-arc curve was described as a locus of operating points during -7, 0, 15, and 60° head-up tilting (HUT) on a PNE-AP plane. The NM-arc curve was drawn as a line between operating points before and after ganglionic blockade (trimethaphan, 0.1 mg⋅ml-1⋅kg-1) during 0° or 15° HUT. Gain values were estimated from the slopes of these functional curves. Finally, an open-loop gain, which is a most important index for performance of arterial baroreflex, was given by a product of the gain values of MN (GMN) and NM arcs (GNM). Gain values of MN was 8.92 ± 3.07 pg⋅ml-1⋅mmHg-1; and GNM at 0° and 15° HUT were 0.61 ± 0.08 and 0.36 ± 0.05 mmHg⋅ml⋅pg-1, respectively. A postural change from supine to 15° HUT significantly reduced the open-loop gain from 5.62 ± 0.98 to 3.75 ± 0.62. The effects of HUT on the NM arc and open-loop gain seemed to be similar to those of blood loss observed in our previous animal studies. CONCLUSION: An equilibrium-diagram analysis contributes to a quantitative and integrative understanding of function of human sympathetic arterial baroreflex.

15.
Shokuhin Eiseigaku Zasshi ; 62(3): 73-78, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-34219099

RESUMO

The main component of the Mustard and Horseradish extracts, which are used as natural food additives in Japan, is allyl isothiocyanate (AITC). The determination of AITC using GC-FID is the official method employed in the quality control assessments for these products. In this method, a commercially available AITC reagent is used as a calibrant. However, 1H-quantitative NMR (qNMR) analysis revealed that the AITC reagents contain impurity. Therefore, we examined the GC-FID and HPLC-refractive index detector (LC-RID) method based on relative molar sensitivities (RMSs) to high-purity single reference (SR). The RMSs of AITC/SR under the GC-FID and LC-RID conditions were accurately determined using qNMR. The AITC in two types of food additives was quantified using qNMR, SR GC-FID, and SR LC-RID methods. Both SR GC-FID and SR LC-RID showed good agreement within 2% with the AITC content determined by direct qNMR.


Assuntos
Armoracia , Mostardeira , Cromatografia Líquida de Alta Pressão , Isotiocianatos , Japão , Dente Molar/química , Extratos Vegetais/análise
16.
Inquiry ; 58: 469580211005192, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33769128

RESUMO

The increase in the elderly population in need of healthcare services has led to a serious shortage in the nursing workforce. To retain a large nursing workforce, a strong work-life balance among nurses is needed along with a healthy work environment. This prospective study investigates the influence of work-life balance and sense of coherence on intention to leave among hospital nurses. A questionnaire survey was conducted with 2239 nurses as a baseline. The explanatory variables included striving for work-life balance behavior, a sense of coherence in terms of personal resources, and work-, organizational-, and individual-related factors. Using a cohort of 1368 valid responses, we measured intention to leave among 975 nurses with whom we were able to follow up 6 months after the baseline survey. We then performed multiple regression analysis. The behavior striving for work-life balance was shown to influence nurses' intention to leave. Nurses who exhibited less striving for work-life balance behavior showed higher intentions to leave. The sense of coherence was not identified as a factor affecting intention to leave. Securing a comfortable work-life balance would reduce the nurses' desire to quit the hospital. To reduce nurse turnover, nurse managers should develop support programs that can help nurses achieve a better work-life balance.


Assuntos
Enfermeiras e Enfermeiros , Recursos Humanos de Enfermagem no Hospital , Senso de Coerência , Idoso , Estudos Transversais , Humanos , Intenção , Satisfação no Emprego , Estudos Prospectivos , Inquéritos e Questionários , Equilíbrio Trabalho-Vida
17.
J Agric Food Chem ; 69(13): 3904-3911, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33761247

RESUMO

Genipin was reacted with benzylamine and several amino acids to prepare gardenia blue (GB). The time-course of GB formation with benzylamine was monitored by high-performance liquid chromatography (HPLC), liquid chromatography time-of-flight mass spectrometry (LC-TOFMS), and 1H and 13C NMR measurements. In this experiment, we determined the molecular structures of some intermediates using accurate masses and additional NMR techniques such as heteronuclear multiple bond correlation (HMBC). GBs with amino acids (GB-AAs) were characterized by both liquid and solid-state NMR measurements. Interestingly, many significant peaks appeared in the solid-state NMR spectra, although the 13C NMR spectra from solution samples did not show any distinct peaks. Therefore, we determined that GB-AAs had an alternating copolymer structure composed of methyne and 5H-2-pyrindine, which was substituted by amino acids at N atom and linked with methyne at 5 and 7 positions. To confirm this molecular structure, the pyrolysis gas chromatography-mass spectrometry (GC-MS) measurement of GB-AAs was carried out, and 5H-2-pyrindine and its methyl derivatives were formed as main pyrolysis products from the polymer chains.


Assuntos
Gardenia , Aminoácidos , Benzilaminas , Iridoides , Estrutura Molecular
18.
Chem Pharm Bull (Tokyo) ; 69(1): 18-25, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33390516

RESUMO

Mogroside V is one of the characteristic and effective components of luohanguo extract, a food additive used as a sweetener in Japan as per Japan's Standards and Specifications for Food Additives (JSFA; 9th ed.). JSFA stipulates that the quantitative determination for mogroside V content in luohanguo extract applies HPLC using analytical standard mogroside V. However, no mogroside V reagents with proven purities are commercially available. Therefore the current JSFA determination method is not particularly suited for daily quality control operations involving luohanguo extract. In this study, we applied an alternative quantitative method using a single reference with relative molar sensitivity (RMS). It was possible to calculate the accurate RMS by an offline combination of 1H-quantitative NMR spectroscopy (1H-qNMR) and an HPLC/variable-wavelength detector (VWD). Using the RMS of mogroside V to a commercial certified reference material grade caffeine, the mogroside V contents in luohanguo extracts could be determined using HPLC/VWD without analytical standard mogroside V. There was no significant difference between the mogroside V contents in luohanguo extracts determined using the method employing single-reference caffeine with the RMS and using the JSFA method. The absolute calibration curve for the latter was prepared using an analytical standard mogroside V whose purity was determined by 1H-qNMR. These results demonstrate that our proposed method using a single reference with RMS is suitable for quantitative determination of mogroside V in luohanguo extract and can be used as an alternative method to the current assay method in JSFA.


Assuntos
Cafeína/análise , Cucurbitaceae/química , Aditivos Alimentares/análise , Extratos Vegetais/análise , Triterpenos/análise , Cafeína/normas , Cromatografia Líquida de Alta Pressão/normas , Aditivos Alimentares/normas , Japão , Espectroscopia de Ressonância Magnética/normas , Extratos Vegetais/normas , Controle de Qualidade , Triterpenos/normas
19.
Food Chem ; 344: 128708, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33272765

RESUMO

A simple and rapid analytical method was developed for the determination of formaldehyde (FA) and acetaldehyde (AA) contents in water. FA and AA were derivatized by 2,4-dinitrophenylhydrazine in an LC vial for 20 min at room temperature, about 25 °C, and analyzed using LC-MS/MS. The calibration curve exhibited excellent linearity for FA and AA concentrations of 2-150 ng/mL. Recovery tests using ultra-pure water and commercially available PET-bottled mineral water samples showed good trueness and precision. We determined the FA and AA contents in 105 PET-bottled mineral water samples on the Japanese market using this method. FA was detected in 61% of the samples at levels from 2.6 to 31.4 ng/mL, while AA was detected in 68% at levels from 5.3 to 143.5 ng/mL. These results demonstrate that the concentrations of FA and AA in PET-bottled mineral water on the Japanese market have not changed significantly over the last decade.


Assuntos
Acetaldeído/análise , Cromatografia Líquida/métodos , Água Potável/química , Formaldeído/análise , Águas Minerais/análise , Polietilenotereftalatos/química , Espectrometria de Massas em Tandem/métodos , Acetaldeído/isolamento & purificação , Formaldeído/isolamento & purificação , Fatores de Tempo
20.
J Sci Food Agric ; 101(9): 3804-3810, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33315241

RESUMO

BACKGROUND: Many studies report the monitoring of catechins in tea samples by chromatographic techniques. Unfortunately, only a small number of screening assays for catechins exist as a result of the complexity of authentic standards for the respective calibration curves. In the present study, a single reference (SR) exhaustive assay for the simultaneous quantification of tea-derived catechins by liquid chromatography (LC) with photodiode array and fluorescence detectors based on relative molar sensitivity (RMS) was developed as a screening assay of common tea samples without respective calibration curves using authentic standards. RESULTS: Three original SR standards were proposed based on flavonoid structures, evaluated by quantitative 1 H-NMR based on an indirect standard (1,4-bis(trimethylsilyl) benzene-d4 ) and successfully separated in a LC chromatogram. In tea samples with these added SR calculated based on RMS, the concentrations of eight tea-derived catechins could be measured with a relative SD of < 8.5% by a single LC run. CONCLUSION: This LC screening assay based on RMS allows reliable quantification without the requirement for respective calibration curves using authentic standards. © 2020 Society of Chemical Industry.


Assuntos
Camellia sinensis/química , Catequina/análise , Cromatografia Líquida de Alta Pressão/normas , Chá/química , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/análise , Padrões de Referência
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