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1.
BMC Public Health ; 23(1): 703, 2023 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-37069558

RESUMO

BACKGROUND: Previous studies have suggested that blood Cd, Pb exposure, and physical activity levels may influence the development of hypertension. This study aimed to investigate the relationship between blood Cd, Pb levels, and hypertension by the level of physical activity in Korean adults using The Korea National Health and Nutrition Examination Survey (KNHANES). METHODS: We used data from the KNHANES (2008-2013), a nationally representative, cross-sectional, population-based study. We included 8,510 participants who had records of blood Cd, Pb and, blood pressure measurements. Multiple logistic regression was used to examine the association between blood Cd and Pb exposure and the development of hypertension, as well as the modifying effects of physical activity levels. Additive interaction was estimated using relative excess risk due to interaction (RERI), attributable proportion due to interaction (AP) and synergy index (S). RESULTS: Following covariates adjustments, we found significant associations of blood Cd and Pb with higher hypertension prevalence. This association was more apparent in low physical activity while blood Cd and Pb concentrations were not significantly associated with hypertension in participants with more activity. Additionally, there was a significant interaction between blood Cd and physical activity on hypertension risk (RERI = 0.17, 95% CI: -0.36-0.7; AP = 0.12, 95% CI: -0.28-0.52; S = 1.75, 95% CI:1.36-2.14). CONCLUSIONS: Our results suggest that low physical activity may substantially amplify the adverse effects of blood Pb and Cd exposure on hypertension risk. However, interactions were only found for Cd. Further studies are needed to confirm these findings.


Assuntos
Cádmio , Hipertensão , Adulto , Humanos , Chumbo , Inquéritos Nutricionais , Estudos Transversais , Exposição Ambiental , Hipertensão/epidemiologia , República da Coreia/epidemiologia
2.
Biochem Biophys Res Commun ; 578: 91-96, 2021 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-34547629

RESUMO

The SARS-CoV-2 variant is rapidly spreading across the world and causes to resurge infections. We previously reported that CT-P59 presented its in vivo potency against Beta variants, despite its reduced activity in cell experiments. Yet, it remains uncertain to exert the antiviral effect of CT-P59 on Gamma, Delta and its associated variants (L452R). To tackle this question, we carried out cell tests and animal studies. CT-P59 showed neutralization against Gamma, Delta, Epsilon, and Kappa variants in cells, with reduced susceptibility. The mouse challenge experiments with Gamma and Delta variants substantiated in vivo potency of CT-P59 showing symptom remission and virus abrogation in the respiratory tract. Collectively, cell and animal studies showed that CT-P59 is effective against Gamma and Delta variants infection, hinting that CT-P59 has therapeutic potential for patients infected with Gamma, Delta and its associated variants.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Anticorpos Neutralizantes/farmacologia , Tratamento Farmacológico da COVID-19 , Modelos Animais de Doenças , Imunoglobulina G/farmacologia , SARS-CoV-2/efeitos dos fármacos , Animais , Antivirais/farmacologia , Peso Corporal/efeitos dos fármacos , COVID-19/virologia , Feminino , Humanos , Camundongos Transgênicos , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Análise de Sobrevida
3.
Biochem Biophys Res Commun ; 566: 135-140, 2021 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-34119826

RESUMO

The global circulation of newly emerging variants of SARS-CoV-2 is a new threat to public health due to their increased transmissibility and immune evasion. Moreover, currently available vaccines and therapeutic antibodies were shown to be less effective against new variants, in particular, the South African (SA) variant, termed 501Y.V2 or B.1.351. To assess the efficacy of the CT-P59 monoclonal antibody against the SA variant, we sought to perform as in vitro binding and neutralization assays, and in vivo animal studies. CT-P59 neutralized B.1.1.7 variant to a similar extent as to wild type virus. CT-P59 showed reduced binding affinity against a RBD (receptor binding domain) triple mutant containing mutations defining B.1.351 (K417N/E484K/N501Y) also showed reduced potency against the SA variant in live virus and pseudovirus neutralization assay systems. However, in vivo ferret challenge studies demonstrated that a therapeutic dosage of CT-P59 was able to decrease B.1.351 viral load in the upper and lower respiratory tracts, comparable to that observed for the wild type virus. Overall, although CT-P59 showed reduced in vitro neutralizing activity against the SA variant, sufficient antiviral effect in B.1.351-infected animals was confirmed with a clinical dosage of CT-P59, suggesting that CT-P59 has therapeutic potential for COVID-19 patients infected with SA variant.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , COVID-19/terapia , COVID-19/virologia , Imunoglobulina G/uso terapêutico , SARS-CoV-2 , Animais , Anticorpos Monoclonais Humanizados/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Modelos Animais de Doenças , Feminino , Furões , Humanos , Imunoglobulina G/imunologia , Técnicas In Vitro , Testes de Neutralização , Pandemias , SARS-CoV-2/genética , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , África do Sul , Carga Viral/imunologia
4.
Nat Commun ; 12(1): 288, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436577

RESUMO

Vaccines and therapeutics are urgently needed for the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we screen human monoclonal antibodies (mAb) targeting the receptor binding domain (RBD) of the viral spike protein via antibody library constructed from peripheral blood mononuclear cells of a convalescent patient. The CT-P59 mAb potently neutralizes SARS-CoV-2 isolates including the D614G variant without antibody-dependent enhancement effect. Complex crystal structure of CT-P59 Fab/RBD shows that CT-P59 blocks interaction regions of RBD for angiotensin converting enzyme 2 (ACE2) receptor with an orientation that is notably different from previously reported RBD-targeting mAbs. Furthermore, therapeutic effects of CT-P59 are evaluated in three animal models (ferret, hamster, and rhesus monkey), demonstrating a substantial reduction in viral titer along with alleviation of clinical symptoms. Therefore, CT-P59 may be a promising therapeutic candidate for COVID-19.


Assuntos
Anticorpos Neutralizantes/farmacologia , Tratamento Farmacológico da COVID-19 , Ligação Proteica/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/efeitos dos fármacos , Enzima de Conversão de Angiotensina 2/química , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/química , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Chlorocebus aethiops , Modelos Animais de Doenças , Feminino , Furões , Humanos , Leucócitos Mononucleares , Macaca mulatta , Masculino , Mesocricetus , Modelos Moleculares , Conformação Proteica , Glicoproteína da Espícula de Coronavírus/química , Células Vero
5.
Food Sci Biotechnol ; 27(3): 859-866, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30263812

RESUMO

Chloropropanols such as 3-monochloropropane-1,2-diol (3-MCPD) and 1,3-dichloropropan-2-ol (1,3-DCP) are produced by heat treatment in the presence of fat and hydrochloric acid during the manufacture of food stuffs such as hydrolyzed vegetable protein and soy sauce. 3-MCPD and 1,3-DCP have been detected in several foods. An efficient, highly selective GC-MS method was developed to determine the concentration of 3-MCPD and 1,3-DCP in food. Calibration curves for 3-MCPD and 1,3-DCP were constructed, and a correlation of determination (r2) ≥ 0.9990 was obtained. The limits of detection and quantitation for 3-MCPD in food were 0.6 and 2.0 µg/kg, respectively, and those for 1,3-DCP were 0.2 and 0.6 µg/kg, respectively. To the best of our knowledge, this GC-MS-based method is a newly improved analytical procedure for the simultaneous separation and determination of 3-MCPD and 1,3-DCP, at once and at low levels (µg/kg).

6.
J Oleo Sci ; 67(5): 507-513, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29628492

RESUMO

The aim of this study was to discriminate the authenticity of perilla oils distributed in Korea using their 1H nuclear magnetic resonance (NMR) spectra acquired by a 43 MHz low-field benchtop NMR spectrometer. Significant differences existed in the integration values of all 6 peaks found in the spectrum between authentic and adulterated perilla oil samples. The integration values of 4 peaks that signify the methylene protons present in all fatty acids (FA) and allylic or olefinic protons present in all unsaturated FA were the best variables for establishing perilla oil authenticity. The procedure for applying the range of variables found in authentic perilla oil samples correctly discriminated between the samples of perilla oils with soybean oils added at concentrations of ≥ 6 vol%. The results demonstrated that this NMR procedure is a possible cost-effective alternative to the high-field 1H NMR method for discriminating the authenticity of perilla oils.


Assuntos
Contaminação de Alimentos/prevenção & controle , Espectroscopia de Ressonância Magnética/métodos , Ácido alfa-Linolênico/análise , Ácido alfa-Linolênico/química , Análise Custo-Benefício , Hidrogênio , Coreia (Geográfico) , Óleos de Plantas/análise , Óleos de Plantas/química , Óleo de Soja
7.
Food Chem ; 255: 112-119, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-29571456

RESUMO

Skates and rays are commercially important fish in South Korea, and among them, Beringraja pulchra has the highest economic value. However, the similar morphological traits among skates and rays are often exploited for seafood fraud. Here, we designed both Beringraja pulchra-specific and skate-universal primer sets, capable of detecting short sequences in the cytochrome oxidase subunit I gene, and developed highly sensitive and reliable quantitative real-time PCR (qPCR) assays to differentiate between Beringraja pulchra and other skate and ray species. AΔCq method based on differences in the amplification efficiency was developed, validated, and then used to confirm the presence of Beringraja pulchra in twenty-six commercial skate products. The averageΔCq value obtained for other skate species (18.94 ±â€¯3.46) was significantly higher than that of Beringraja pulchra (1.18 ±â€¯0.15). For on-site applications, we developed an ultra-fast qPCR assay, allowing for completion of the entire analytical procedure within 30 min.


Assuntos
Produtos Pesqueiros/análise , Análise de Alimentos/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Rajidae/genética , Animais , Primers do DNA , Complexo IV da Cadeia de Transporte de Elétrons/genética , Proteínas de Peixes/genética , Reprodutibilidade dos Testes , República da Coreia , Especificidade da Espécie
8.
Mitochondrial DNA B Resour ; 3(2): 1075-1076, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-33474421

RESUMO

The complete chloroplast genome sequence of Codonopsis lanceolata was determined by next generation sequencing. The total length of chloroplast genome of C. lanceolata was 169,447 bp long, including a large single-copy (LSC) region of 85,253 bp, a small single-copy (SSC) region of 8060 bp, and a pair of identical inverted repeat regions (IRs) of 38,067 bp. A total of 110 genes was annotated, resulting in 79 protein-coding genes, 27 tRNA genes, and 4 rRNA genes. The phylogenetic analysis of C. lanceolata with related chloroplast genome sequences in this study provided the taxonomical relationship of C. lanceolata in the genus Campanula.

9.
Mitochondrial DNA B Resour ; 3(2): 1090-1091, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-33474427

RESUMO

The complete chloroplast genome sequence of Caltha palustris, a species of the Ranunculaceae family, was characterized from the de novo assembly of HiSeq (Illumina Co.) paired-end sequencing data. The chloroplast genome of C. palustris was 155,292 bp in length, with a large single-copy (LSC) region of 84,120 bp, a small single-copy (SSC) region of 18,342 bp, and a pair of identical inverted repeat regions (IRs) of 26,415 bp. The genome contained a total of 114 genes, including 80 protein-coding genes, 30 transfer RNA (tRNA) genes, and 4 ribosomal RNA (rRNA) genes. The phylogenetic analysis of C. palustris with 14 related species revealed the closest taxonomical relationship with Hydrastis canadensis in the Ranunculaceae family.

10.
Artigo em Inglês | MEDLINE | ID: mdl-29197303

RESUMO

A new sildenafil analogue was detected during the monitoring of a premixed powder intended as a dietary supplement. The ultraviolet (UV) spectrum of the unknown compound was similar to that of dithiodesmethylcarbodenafil and dithiodesethylcarbodenafil, although their corresponding HPLC peaks were observed at different retention times. The chemical structure of the unknown compound was characterized by liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-Q-TOF/MS), followed by nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy. The comparison of its structure with that of dithiodesmethylcarbodenafil, revealed that the N-methyl group on the piperazine ring is replaced by a propyl group. This new sildenafil analogue was identified as 5-(2-ethoxy-5-(4-propylpiperazine-1-carbonothioyl)phenyl)-1-methyl-3-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidine-7-thione and designated as a dithiopropylcarbodenafil. To the best of our knowledge, this is the first study reporting the identification and characterization of dithiopropylcarbodenafil.


Assuntos
Citrato de Sildenafila/análogos & derivados , Citrato de Sildenafila/química , Cromatografia Líquida , Suplementos Nutricionais/análise , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Citrato de Sildenafila/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrofotometria Infravermelho
11.
J Sci Food Agric ; 97(12): 3877-3896, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28397254

RESUMO

This review provides current information on the analytical methods used to identify food adulteration in the six most adulterated food categories: animal origin and seafood, oils and fats, beverages, spices and sweet foods (e.g. honey), grain-based food, and others (organic food and dietary supplements). The analytical techniques (both conventional and emerging) used to identify adulteration in these six food categories involve sensory, physicochemical, DNA-based, chromatographic and spectroscopic methods, and have been combined with chemometrics, making these techniques more convenient and effective for the analysis of a broad variety of food products. Despite recent advances, the need remains for suitably sensitive and widely applicable methodologies that encompass all the various aspects of food adulteration. © 2017 Society of Chemical Industry.


Assuntos
Técnicas de Química Analítica/métodos , Contaminação de Alimentos/análise , Animais , Bebidas/análise , Suplementos Nutricionais/análise , Carne/análise , Alimentos Marinhos/análise , Especiarias/análise
12.
Food Sci Biotechnol ; 26(5): 1185-1190, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30263651

RESUMO

Recently, amphetamine-like substances derived from the ß-phenylethylamine core structure have been detected in dietary supplements. Especially, ß-methylphenylethylamine (BMPEA), an amphetamine isomer, has been found in dietary supplements labeled as containing Acacia rigidula. The U. S. Food and Drug Administration determined that BMPEA is not naturally present in food and does not meet the statutory definition of a dietary ingredient. In addition, BMPEA has been classified as a psychotropic drug in South Korea and a doping substance by the World Anti-Doping Agency. The aim of this study was to determine whether dietary supplements contained amphetamine and amphetamine-like substance, including ß-phenylethylamine (ß-PEA) and BMPEA using LC-PDA and LC-MS/MS. In 10 of 110 samples, illegally added compounds were detected in the following ranges; ß-PEA 1.4-122.0 mg/g and BMPEA 4.7-37.6 mg/g. This study will contribute to enhancement of food safety in the South Korea.

13.
Genomics Inform ; 14(3): 85-89, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27729837

RESUMO

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that affects multiple organ systems. Although the etiology of SLE remains unclear, it is widely accepted that genetic factors could be involved in its pathogenesis. A number of genome-wide association studies (GWASs) have identified novel single-nucleotide polymorphisms (SNPs) associated with the risk of SLE in diverse populations. However, not all the SNP candidates identified from non-Asian populations have been validated in Koreans. In this study, we aimed to replicate the SNPs that were recently discovered in the GWAS; these SNPs have not been validated in Koreans or have only been replicated in Koreans with an insufficient sample size to conclude any association. For this, we selected five SNPs (rs1801274 in FCGR2A and rs2286672 in PLD2, rs887369 in CXorf21, rs9782955 in LYST, and rs3794060 in NADSYN1). Through the replication study with 656 cases and 622 controls, rs1801274 in FCGR2A was found to be significantly associated with SLE in Koreans (odds ratio, 1.26, 95% confidence interval, 1.06 to 1.50; p = 0.01 in allelic model). This association was also significant in two other models (dominant and recessive). The other four SNPs did not show a significant association. Our data support that FCGR polymorphisms play important roles in the susceptibility to SLE in diverse populations, including Koreans.

14.
Food Chem ; 211: 253-9, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27283629

RESUMO

Gelatin, a purified protein derived mostly from pig skin and bovine tissue, is used widely in both food and pharmaceutical industries. Here, to determine the species of origin of capsule gelatin, we developed a sensitive and reliable test using the polymerase chain reaction (PCR) method, which included 1) species-specific or universal primer sets, designed to detect short 16S ribosomal RNA (rRNA) gene sequences from cow, pig, and fish (tilapia) as well as genes encoding the large subunit of plant ribulose-1,5-bisphosphate carboxylase oxygenase and 2) species-specific PCR coupled with whole-genome amplification. This method was used to verify manufacturing label claims of 28 gelatin capsule samples sold as dietary supplements. The results from 27 samples were consistent with gelatin-related information on the manufacturer label, while one sample that mentioned tilapia gelatin was found to contain only bovine DNA. This rapid method can therefore be used to verify the authenticity of gelatin capsules.


Assuntos
Suplementos Nutricionais/análise , Gelatina/análise , Reação em Cadeia da Polimerase/métodos , RNA Ribossômico 16S/análise , Animais , Cápsulas , Bovinos , DNA/análise , Primers do DNA/genética , Produtos Pesqueiros/análise , Gelatina/química , Genes de Plantas , Genoma , Derivados da Hipromelose/química , Ipomoea batatas , Carne/análise , Especificidade da Espécie , Suínos , Tilápia
15.
Food Chem ; 167: 363-9, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25148999

RESUMO

The aim of this study was to investigate the effects of the geographic location and climatic characteristics of the sesame-producing sites on the carbon, hydrogen, and oxygen stable isotope ratios of Korean sesame oil. In addition, the study aimed to differentiate Korean sesame oil from Chinese and Indian sesame oils using isotopic data in combination with canonical discriminant analysis. The isotopic data were obtained from 84 roasted oil samples that were prepared from 51 Korean, 19 Chinese, and 14 Indian sesame seeds harvested during 2010-2011 and distributed in Korea during the same period. The δ(13)C, δD, and δ(18)O values of Korean sesame oil were negatively correlated with latitude, distance from the sea, and precipitation (May-September), respectively. By applying two canonical discriminant functions, 89.3% of the sesame oil samples were correctly classified by their geographic origin, indicating that the triple-isotope approach is a useful tool for the traceability of the oils.


Assuntos
Isótopos/análise , Óleo de Gergelim/análise , Ásia , Oxigênio/análise , Óleos de Plantas/análise
16.
Asian Pac J Cancer Prev ; 15(7): 3279-86, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24815483

RESUMO

BACKGROUND: Cancer is one of the leading causes of death in Korea. To reduce cancer incidence, the Korean National Cancer Center (KNCC) has been expanding its organized cancer screening program. In addition, there are opportunistic screening programs that can be chosen by individuals or their healthcare providers. The purpose of this study was to investigate factors associated with participation in organized and opportunistic cancer screening programs, with a particular focus on socioeconomic factors. MATERIALS AND METHODS: We used data from the Korea National Health and Nutrition Examination Survey (KNHANES), a cross-sectional nationwide study conducted by the Korean Ministry of Health and Welfare from 2007 to 2011. The study included information from 9,708 men and 12,739 women aged 19 years or over. Multinomial logistic regression analysis was conducted, adjusting for age, year of data collection, residential region, current smoking status, current alcohol consumption status, exercise, marriage status, job status, perceived health status, stress level, BMI, limitation of activities, cancer history, health insurance type, and private insurance status, to investigate the association between education level, economic status, and cancer screening participation. RESULTS: In terms of education level, disparities in attendance were observed only for the opportunistic screening program. In contrast, there was no association between education level and participation in organized screening. In terms of economic status, disparities in opportunistic screening participation were observed at all income levels, but disparities in organized screening participation were observed only at the highest income level. CONCLUSIONS: Our findings reveal that socioeconomic factors, including educational level and economic status, were not significantly associated with participation in organized cancer screening, except at the highest level of income.


Assuntos
Detecção Precoce de Câncer/estatística & dados numéricos , Programas de Rastreamento/estatística & dados numéricos , Neoplasias/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Cooperação do Paciente/estatística & dados numéricos , Adulto , Idoso , Estudos Transversais , Escolaridade , Feminino , Humanos , Cobertura do Seguro , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , República da Coreia , Fatores Socioeconômicos , Inquéritos e Questionários
17.
Lab Anim Res ; 27(1): 37-40, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21826158

RESUMO

This study was developed and validated for the determination of oxyclozanide residue concentrations in beef and commercial milk, using high-performance liquid chromatography system. Oxyclozanide was successfully separated on a reverse phase column (Xbridge-C(18), 4.6×250 mm, 5 µm) with a mobile phase composed of acetonitrile and 0.1% phosphoric acid (60:40, v/v%). This analytical procedure involved a deproteinization process using acetonitrile for beef and 2% formic acid in acetonitrile for commercial milk, dehydration by adding sodium sulfate to the liquid analytical sample, and a defatting process using n-hexane; after these steps, the extract was exposed to a stream of nitrogen dryness. The final extracted sample was dissolved in the mobile phase and filtered using a 0.45 µm syringe filter. This method had good selectivity and recovery (70.70±7.90-110.79±14.95%) from the matrices. The LOQs ranged from 9.7 to 9.8 µg/kg for beef and commercial milk. The recoveries met the standards set by the CODEX guideline.

18.
J Food Prot ; 72(9): 1916-22, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19777894

RESUMO

Securing the physical quality and microbial safety of fresh foods has been a major focus in the food industry. To improve quality and increase the shelf life of fresh produce, disinfection methods have been developed. Titanium dioxide (TiO2) photocatalytic reactions under UV radiation produce hydroxyl radicals that can be used for disinfection of foodborne pathogenic bacteria. We investigated the effects of TiO2-UV photocatalytic disinfection on the shelf life of iceberg lettuce. Counts of natural microflora (total aerobic bacteria, coliforms, psychrotrophic bacteria, and yeasts and molds) and inoculated pathogenic bacteria (Escherichia coli, Listeria monocytogenes, Staphylococcus aureus, and Salmonella Typhimurium) on iceberg lettuce were determined after 20-min treatments with TiO2-UV, UV radiation, a sodium hypochlorite (NaOCl) solution, and tap water. TiO2-UV treatment reduced the number of microorganisms by 1.8 to 2.8 log CFU/g compared with reductions of 0.9 to 1.4 and 0.7 to 1.1 log CFU/g obtained with UV radiation and NaOCl treatments, respectively. Treatment with tap water was used as a control and resulted in no reductions. Counts of microflora for iceberg lettuce at 4 and 25 degrees C were determined during a 9-day period. TiO2-UV treatment resulted in 1.2- and 4.3-log increases in the counts of total aerobic bacteria at 4 and 25 degrees C, respectively, compared with 1.3- to 1.6-log and 4.4- to 4.8-log increases due to UV radiation and NaOCl treatments.


Assuntos
Bactérias/efeitos da radiação , Irradiação de Alimentos/métodos , Lactuca/microbiologia , Fármacos Fotossensibilizantes/farmacologia , Titânio/farmacologia , Bactérias/crescimento & desenvolvimento , Contagem de Colônia Microbiana , Qualidade de Produtos para o Consumidor , Desinfecção/métodos , Lactuca/efeitos da radiação , Fatores de Tempo , Raios Ultravioleta
19.
J Food Sci ; 73(9): M418-22, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19021812

RESUMO

Inactivation of Escherichia coli O157:H7, Salmonella typhimurium, and Listeria monocytogenes in iceberg lettuce by aqueous chlorine dioxide (ClO(2)) treatment was evaluated. Iceberg lettuce samples were inoculated with approximately 7 log CFU/g of E. coli O157:H7, S. typhimurium, and L. monocytogenes. Iceberg lettuce samples were then treated with 0, 5, 10, or 50 ppm ClO(2) solution and stored at 4 degrees C. Aqueous ClO(2) treatment significantly decreased the populations of pathogenic bacteria on shredded lettuce (P < 0.05). In particular, 50 ppm ClO(2) treatment reduced E. coli O157:H7, S. typhimurium, and L. monocytogenes by 1.44, 1.95, and 1.20 log CFU/g, respectively. The D(10)-values of E. coli O157:H7, S. typhimurium, and L. monocytogenes in shredded lettuce were 11, 26, and 42 ppm, respectively. The effect of aqueous ClO(2) treatment on the growth of pathogenic bacteria during storage was evaluated, and a decrease in the population size of these pathogenic bacteria was observed. Additionally, aqueous ClO(2) treatment did not affect the color of lettuce during storage. These results suggest that aqueous ClO(2) treatment can be used to improve the microbial safety of shredded lettuce during storage.


Assuntos
Compostos Clorados/farmacologia , Desinfetantes/farmacologia , Escherichia coli O157/efeitos dos fármacos , Lactuca/metabolismo , Listeria monocytogenes/efeitos dos fármacos , Óxidos/farmacologia , Salmonella typhimurium/efeitos dos fármacos , Escherichia coli O157/efeitos da radiação , Manipulação de Alimentos , Frutas/microbiologia , Frutas/normas , Lactuca/efeitos dos fármacos , Lactuca/efeitos da radiação , Listeria monocytogenes/efeitos da radiação , Salmonella typhimurium/efeitos da radiação , Raios Ultravioleta , Verduras/microbiologia , Verduras/normas
20.
J Microbiol ; 46(4): 436-40, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18758735

RESUMO

The molecular methods using polymerase chain reaction have been proposed as useful tools for the identification of viral pathogens in food and water. However, the PCR-based methods are highly dependent on the methods of virus concentration and nucleic acid purification due to the low sensitivity of PCR in the presence of PCR inhibitors. We developed TPTT [tris elution buffer-PEG-TRIzol-poly(dT) magnetic bead] protocol in order to detect hepatitis A virus (HAV) inoculated in oyster digestive glands. The detection limit of HAV precipitated with zirconium hydroxide was 10(5) fold less sensitive in a nested PCR than that precipitated the HAV supernatant twice with PEG/NaCl (16% polyethylene glycol 6,000, 0.525 M NaCl) in a 1:2 (v/v) ratio, which provided an efficient detection of 0.0148 PFU/g from approximately 0.05 g of oyster homogenate. This method is efficient for potential use in the detection of HAV from shellfish and is more sensitive than most currently published tests.


Assuntos
Microbiologia de Alimentos , Vírus da Hepatite A/isolamento & purificação , Ostreidae/virologia , Reação em Cadeia da Polimerase/métodos , RNA Viral/isolamento & purificação , Animais , Contaminação de Alimentos/prevenção & controle , Vírus da Hepatite A/genética , Polietilenoglicóis/química , RNA Viral/genética , Sensibilidade e Especificidade
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