Este es uno de los estudios científicos, recientemente publicados, que se ha enfocado en registrar la cantidad del compuesto 4-Metilidimazol que se encuentra en las bebidas de Cola y en la cerveza oscura. El compuesto 4-Metilidimazol es un subproducto cancerígeno que se encuentra en el colorante Caramelo IV utilizado en estas bebidas. El estudio reconoce que la mayor ingesta que se da de este compuesto es a través de las bebidas de Cola. Estima que en los Estados Unidos el consumo promedio diario de bebidas de Cola puede representar una ingesta de 342 microgramos diarios de 4-Metilidimazol. Esta cantidad significa varias veces el nivel máximo recomendado como seguro de ingesta de este compuesto sugerido por la autoridad de California, para todo un día que es de 16 microgramos al día. El estudio reporta que una sola lata de bebida de Cola puede contener entre 12.95 y 214.55 microgramos de 4-Metilidimazol.
Separation of L-Phenylalanine by Solvent Sublation and Solvent Extraction MethodBRNSS Publication Hub
Aims and Objectives: Separation and purification is a series of processes intended to isolate a single type of biomolecule from a complex mixture. Innovations in improvement of biodownstream processing, which is responsible for the separation of about 50–80% of recombinant proteins and other biomolecules, play a very important role in increasing the yield and reducing the cost of biopharmaceutical production. Methods: Biomolecule isolation and purification from a fermentation broth usually involve centrifugation, filtration, adsorption, and chromatography steps. Results and Discussions: Each step contributes to the product cost and product loss. Thus, we consider that solvent extraction and solvent sublation are the more economic processes for the separation of biomolecules. Conclusion: In extraction of phenylalanine, maximum extraction was observed at amino acid: surfactant ratio 1:1, amino acid: extractant ratio 1:1500, and pH at 3.1. The highest value of % recovery percentage and Co/Cw was 76.3 and 10.21, respectively. The main motive of this article is to provide the advantages of study on the solvent sublation and solvent extraction of l-phenylalanine over the other techniques.
Flavonoids classification, isolation and identificationMona Ismail
Flavonoids are groups of polyphenolic compounds which are found in fruits, flowers, seeds & vegetable.
(named from the Latin word flavus meaning yellow, their colour in nature)
Metabolic Changes of Drugs and Related Organic Compounds describes the human metabolic processes of various functional groups found in therapeutic agents.
The importance of a chapter on metabolism lies in the fact that drug interactions are based on these processes.
For pharmacists, it is necessary for them to understand why certain drugs are contraindicated with other drugs.
This chapter attempts to describe the various phases of drug metabolism, the sites where these biotransformation will occur, the role of specific enzymes, metabolism of specific functional groups, and several examples of the metabolism of currently used therapeutic agents.
Separation of L-Phenylalanine by Solvent Sublation and Solvent Extraction MethodBRNSS Publication Hub
Aims and Objectives: Separation and purification is a series of processes intended to isolate a single type of biomolecule from a complex mixture. Innovations in improvement of biodownstream processing, which is responsible for the separation of about 50–80% of recombinant proteins and other biomolecules, play a very important role in increasing the yield and reducing the cost of biopharmaceutical production. Methods: Biomolecule isolation and purification from a fermentation broth usually involve centrifugation, filtration, adsorption, and chromatography steps. Results and Discussions: Each step contributes to the product cost and product loss. Thus, we consider that solvent extraction and solvent sublation are the more economic processes for the separation of biomolecules. Conclusion: In extraction of phenylalanine, maximum extraction was observed at amino acid: surfactant ratio 1:1, amino acid: extractant ratio 1:1500, and pH at 3.1. The highest value of % recovery percentage and Co/Cw was 76.3 and 10.21, respectively. The main motive of this article is to provide the advantages of study on the solvent sublation and solvent extraction of l-phenylalanine over the other techniques.
Flavonoids classification, isolation and identificationMona Ismail
Flavonoids are groups of polyphenolic compounds which are found in fruits, flowers, seeds & vegetable.
(named from the Latin word flavus meaning yellow, their colour in nature)
Metabolic Changes of Drugs and Related Organic Compounds describes the human metabolic processes of various functional groups found in therapeutic agents.
The importance of a chapter on metabolism lies in the fact that drug interactions are based on these processes.
For pharmacists, it is necessary for them to understand why certain drugs are contraindicated with other drugs.
This chapter attempts to describe the various phases of drug metabolism, the sites where these biotransformation will occur, the role of specific enzymes, metabolism of specific functional groups, and several examples of the metabolism of currently used therapeutic agents.
C–H bond hydroxylation at non heme carboxylate-bridged diiron centersDaniel Morton
This unit provides an overview of how Nature has inspired the development of novel diiron bridged complexes for use in C–H Hydroxylation.
Contributed by Omar Villanueva and Cora MacBeth, Emory University, 2014
Lipid profiling and corresponding biodiesel quality of mortierella isabellina...zhenhua82
Four lipid extraction methods (Bligh & Dyer, hexane & isopropanol, dichloromethane & methanol, and hexane) were evaluated to extract lipid from freeze- and oven-dried fungus Mortierella isabellina ATCC42613. The highest lipid yield (41.8%) was obtained from Bligh & Dyer extraction on the oven-dried fungal biomass with a methanol:chloroform:water ratio of 2:1:0.8. Other lipid extraction methods on both freeze- and oven-dried samples had lipid yields ranging from 20.7% to 35.9%. Non-polar lipid was the main lipid class (more than 90% of total lipid) in M. isabellina. Regarding fatty acid profile, there was no significant difference on fatty acid concentration between different drying and extraction methods. Estimation of biodiesel fuel properties using correlative models further demonstrated that the fungal biodiesel is a good alternative to fossil diesel.
In this work a new prodrug polymer was
prepared with two attachment groups (amid-ester), using di
functional spacer such as ethanol amine, which could react with
polyacrylic acid producing amide group, with remain ethanol
terminal group which could react with captopril acyl chloride,
producing ester group with extended the arm substituted drug to
improve the hydrolysis and to prevent the steric effect of polymer
chains. Many advantages enhanced the prodrug of polymer. The
prepared polymers were characterized by FTIR, 1H –NMR
spectroscopies. Controlled drug release was studied in different
pH values at 37℃, using UV. Spectra with comparing with
calibration curve. The modification percentage test was studied,and swelling percentage was calculated and all physical properties were observed.
C–H bond hydroxylation at non heme carboxylate-bridged diiron centersDaniel Morton
This unit provides an overview of how Nature has inspired the development of novel diiron bridged complexes for use in C–H Hydroxylation.
Contributed by Omar Villanueva and Cora MacBeth, Emory University, 2014
Lipid profiling and corresponding biodiesel quality of mortierella isabellina...zhenhua82
Four lipid extraction methods (Bligh & Dyer, hexane & isopropanol, dichloromethane & methanol, and hexane) were evaluated to extract lipid from freeze- and oven-dried fungus Mortierella isabellina ATCC42613. The highest lipid yield (41.8%) was obtained from Bligh & Dyer extraction on the oven-dried fungal biomass with a methanol:chloroform:water ratio of 2:1:0.8. Other lipid extraction methods on both freeze- and oven-dried samples had lipid yields ranging from 20.7% to 35.9%. Non-polar lipid was the main lipid class (more than 90% of total lipid) in M. isabellina. Regarding fatty acid profile, there was no significant difference on fatty acid concentration between different drying and extraction methods. Estimation of biodiesel fuel properties using correlative models further demonstrated that the fungal biodiesel is a good alternative to fossil diesel.
In this work a new prodrug polymer was
prepared with two attachment groups (amid-ester), using di
functional spacer such as ethanol amine, which could react with
polyacrylic acid producing amide group, with remain ethanol
terminal group which could react with captopril acyl chloride,
producing ester group with extended the arm substituted drug to
improve the hydrolysis and to prevent the steric effect of polymer
chains. Many advantages enhanced the prodrug of polymer. The
prepared polymers were characterized by FTIR, 1H –NMR
spectroscopies. Controlled drug release was studied in different
pH values at 37℃, using UV. Spectra with comparing with
calibration curve. The modification percentage test was studied,and swelling percentage was calculated and all physical properties were observed.
DTC Lab Kickoff: Data Viz Content Mashup Agnes Chang (NY Times R&D Lab) Talk DTC Lab
The DTC Lab will be paying attention to ways that data visualization can be applied to expand the types of data we track and the ways of interacting with information to create new learning and progress in learning.
La industria procesadora de alimentos y la industria química ha dicho por décadas que todos los aditivos utilizados en alimentos han sido probados y que no existe riesgo de utilizarlos. Sin embargo, la historia de los aditivos en los alimentos está llena de casos en que, después de muchos años de ser utilizados, se encontró que realmente sí tenían impactos en la salud. Los aditivos enlistados a continuación han sido prohibidos, después de que las autoridades internacionales y nacionales aseguraron a los consumidores que estos eran totalmente seguros. La moraleja de la historia es que cuando alguien diga que todos los aditivos de alimentos fueron muy bien probados y no tienen riesgo alguno, se deben tomar estas aseveraciones con muchas reservas. Fuente: Center for Science in the Public Interest (CSPI).
Colorantes en alimentos y bebidas que alteran la conducta infantilToxiColaOrg
Desde los años 70´s el pediatra Benjamin Feingold aseguró que existía una relación entre los aditivos y la manera en la que se comportaban los pequeños. Cuarenta años después, el gobierno del Reino Unido, después de una serie de estudios, ha reconocido que cinco colorantes (tartrazina, carmoisina, rojo allura, amarillo ocaso, rojo ponceau 4R) de uso muy común, generan hiperactividad y déficit de atención en los niños. Un estudio realizado en América Latina encontró que la mayor parte de los ´productos comercializados para niños y niñas (bebidas, botanas, pastelillos, postres y yogurts) contienen uno, dos y hasta tres de estos colorantes artificiales.
Estos colorantes pueden provocar problemas de aprendizaje en momentos claves del desarrollo de los individuos, pueden generar tensiones en la relación entre maestros y alumnos, padres e hijos. A pesar de las pruebas, los intereses de la industria procesadora de alimentos han impedido que se prohíba su uso a escala internacional. En este caso, como en muchos otros, como el del colorante caramelo IV, pueden pasar años hasta que sea retirado del mercado, con las consecuencias que para la salud significa su permanencia en el mercado.
La información entre los consumidores es fundamental para evitar el consumo de los productos que contienen estos colorantes. Una vez que las empresas ven que esta información circula entre los consumidores y que puede afectar su imagen y ventas, los retiran de sus productos.
Para proteger a sus hijos y a usted lea este artículo.
DOC2 - No significant risk levels 4 MI - CaliforniaToxiColaOrg
Esta es la propuesta que está presentando la Oficina de Riesgos Ambientales en la Salud de la Agencia de Protección Ambiental de California para establecer un nivel máximo de ingesta diaria de 4-Metilidimadazol (compuesto cancerígeno que se encuentra en el Caramelo IV utilizado en las bebidas de Cola) que no signifique riesgo a la salud. La propuesta de la autoridad en California es que no se consuma más de 16 microgramos de este compuesto en todo un día. Como se ve en el DOC3, la cantidad de 4-Metilidimadazol que se encuentra en una lata de bebida de cola puede ser 8 veces más de este límite.
Esta es una carta elaborada por expertos en toxicología que respaldaron la solicitud presentada por el Centro por la Ciencia de Interés Público (Center for Science in the Public Interest) ante la Administración de Alimentos y Medicamentos (Food and Drug Administration) de los Estados Unidos para que se prohíba el uso del colorante Caramelo IV por contener el compuesto cancerígeno 4-Metilidimazol (ver DOC4). Los científicos advierten el riesgo que significa el consumo del colorante Caramelo IV presente en las bebidas de Cola por contener un compuesto cancerígeno.
DOC4 - CSPI - Caramel IV Petition to FDAToxiColaOrg
Esta es la petición que presento en febrero de 2011 el Centro por la Ciencia de Interés Público (Center for Science in the Public Interest) ante la Administración de Alimentos y Medicamentos (Food and Drug Administration) de los Estados Unidos para que se prohíba el uso del colorante Caramelo IV por contener el compuesto cancerígeno 4-Metilidimazol. La petición presenta la evidencia existente sobre el potencial cancerígeno del compuesto 4-Metilidimazol (ver DOC1), los niveles máximos que se están recomendando como tolerables en California para la ingesta de este compuesto (ver DOC2) y las cantidades de 4-Metilidimazol que se han registrado en bebidas de Cola que rebasan por mucho lo recomendado (ver DOC3).
DOC1 - National Toxicology Program - Toxicology and Carcinogenesis 4 MIToxiColaOrg
Este es el único estudio realizado en seres vivos para evaluar el potencial toxicológico y cancerígeno del compuesto 4-Metilidimadazol que se encuentra en el colorante Caramelo IV usado por Coca Cola, las bebidas de Cola y otros productos. Fue realizado por el Programa Nacional de Toxicología del Servicio de Salud Pública de los Estados Unidos en 2007. Para evaluar el riesgo que pueden presentar para la salud humana diversos compuestos, se realizan estudios en animales, considerando que si hay un efecto negativo en su salud, estos compuestos no deberían ser consumidos por las personas. El estudio se realizó en ratas y ratones durante dos años y su conclusión fue: "Concluimos que el 4-Metilidimadazol causa cáncer de pulmón en ratones machos y hembras. El 4-Metilidimazol se puede asociar también con el desarrollo de leucemia en ratas hembras".
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
- Video recording of this lecture in English language: https://youtu.be/lK81BzxMqdo
- Video recording of this lecture in Arabic language: https://youtu.be/Ve4P0COk9OI
- Link to download the book free: https://nephrotube.blogspot.com/p/nephrotube-nephrology-books.html
- Link to NephroTube website: www.NephroTube.com
- Link to NephroTube social media accounts: https://nephrotube.blogspot.com/p/join-nephrotube-on-social-media.html
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Basavarajeeyam is an important text for ayurvedic physician belonging to andhra pradehs. It is a popular compendium in various parts of our country as well as in andhra pradesh. The content of the text was presented in sanskrit and telugu language (Bilingual). One of the most famous book in ayurvedic pharmaceutics and therapeutics. This book contains 25 chapters called as prakaranas. Many rasaoushadis were explained, pioneer of dhatu druti, nadi pareeksha, mutra pareeksha etc. Belongs to the period of 15-16 century. New diseases like upadamsha, phiranga rogas are explained.
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
1. Journal of Food Composition and Analysis 24 (2011) 609–614
Contents lists available at ScienceDirect
Journal of Food Composition and Analysis
journal homepage: www.elsevier.com/locate/jfca
Original Article
Assessment of 4-(5-)methylimidazole in soft drinks and dark beer
S.C. Cunha a, A.I. Barrado b, M.A. Faria a, J.O. Fernandes a,*
a
REQUIMTE/Department of Bromatology, Faculty of Pharmacy, University of Porto, Rua de Anı´bal Cunha 164, 4099-030 Porto, Portugal
b
´n
CIEMAT/Unidad de Cromatografı´a, Divisio de Quı´mica, Dpto. de Tecnologı´a, Avd. Complutense 22, 28040 Madrid, Spain
A R T I C L E I N F O A B S T R A C T
Article history: A faster and more robust version of a previously developed method based on ion-pair extraction,
Received 11 January 2010 acylation with isobutylchloroformate and gas chromatography–mass spectrometry (GC–MS) analysis
Received in revised form 4 August 2010 for determination of 4-(5-)methylimidazole (4-MeI) in soft drinks and dark beer is proposed. The
Accepted 13 August 2010
performance of the method was evaluated in terms of linearity (r always > 0.998); recovery (90–101%, 3
Available online 7 December 2010
levels); and precision (3–8%, 3 levels, n = 6). Limits of detection and quantification in the matrices
studied were 0.60 mg/L and 2.2 mg/L, respectively. The optimized method was applied to a wide variety
Key words:
of soft drinks (brand name and generic colas, uncarbonated flavor and energy drinks) and dark beers
4-(5-)Methylimidazole
Caramel
(lager, ales trappist, ales-stout, weissbier). Overall, soft drinks presented higher amounts of 4-MeI
Soft drinks (ranging from 37 to 613 mg/L) than those found in the dark beers (ranging from 3 to 424 mg/L), with colas
Beer presenting the highest levels. When the different colas analyzed were compared, the 4-MeI levels in
Ion-pair extraction generic colas were generally higher than those in brand-name colas. 4-MeI was found in only one of eight
GC–MS energy drinks studied. Based on available consumption patterns, consumer exposure to the maximum 4-
Food analysis MeI given by the soft drinks was 2.3 and 5.7 mg/kg body weight/day, in Europe and the United States,
Food composition respectively.
ß 2010 Elsevier Inc. All rights reserved.
1. Introduction as a flavor additive, while the other three classes are regarded as
coloring agents by the food industry.
The importance of color perception in the food market can be During the caramelization process a wide range of compounds
assessed by popular sayings such as, ‘‘We eat first with our eyes’’. are generated, some of which are considered ‘‘caramel markers.’’
Color additives have been widely used by the food industry to These markers are molecules with low molecular weight such as
attract consumer attention, stimulate or improve appetite. Among 4-(5-)methylimidazole (4-MeI) present in class III and IV; 2-
the oldest food color additives are caramel colors, which are brown acetyl-4(5)-tetrahydroxybutylimidazole (THI) present only in
to brown-black viscous liquids or hygroscopic powders. This group class III; and 5-hydroxymethyl-2-furaldehyde (5-HMF), which is
of additives is still used by the food industry today in a wide range present in all four classes of caramel (Pintea, 2008; Delgado-
of foods and beverages because of its color, flavor and other ´
Vargas and Paredes-Lopez, 2003). The occurrence of these
properties such as stabilization of colloidal systems and prevention markers could be used with authentication purposes; for
of haze formation in beers. Furthermore caramel has emulsifying example, the content of furfural and 5-HMF and their respective
properties, facilitating the dispersion of water-insoluble materials, ratios have been used to detect whiskey adulteration (Jaganathan
retarding flavor changes and preserving the shelf-life of beverages and Dugar, 1999).
´
exposed to light (Delgado-Vargas and Paredes-Lopez, 2003). The presence of these minor caramel components in most foods
Caramels are produced by controlled heating of rich carbohy- and beverages, however, can be hazardous to humans because of
drate sources in the presence of certain reactants such as acids, toxicity. 4-MeI is a neurotoxic agent (Patey et al., 1985) and some in
alkalis, salts, ammonium salts, and sulfites, which results in a vitro studies have shown its capability to inhibit the cytochrome
complex mixture of compounds. According to the method and P450 isoenzyme which catalyses the oxidation of many known or
reactant used, caramels are classified into four classes: (I) plain suspected carcinogens of low molecular mass in the human liver
caramel E150a; (II) caustic sulfite caramel E150b; (III) ammonia (Hargreaves et al., 1994). Furthermore, a recent toxicological study
caramel E150c and (IV) sulfite ammonia caramel E150d (Commis- conducted by the National Institute of Environmental Health
sion Directive 2008/128/EC; JECFA, 2009). The first is used mainly Sciences of USA (Chan et al., 2008) showed that 4-MI can induce
alveolar/bronchiolar adenoma and carcinoma in male and female
mice. THI in turn has been related to immunosuppressive effects
* Corresponding author. Tel.: +351 222078910; fax: +351 222003977.
(Reeve et al., 1993), while 5-HMF is considered an irritant to the
E-mail address: josefer@ff.up.pt (J.O. Fernandes). eyes, upper respiratory tract, skin and mucous membranes.
0889-1575/$ – see front matter ß 2010 Elsevier Inc. All rights reserved.
doi:10.1016/j.jfca.2010.08.009
2. 610 S.C. Cunha et al. / Journal of Food Composition and Analysis 24 (2011) 609–614
The Codex Alimentarius of the World Health Organization phosphate buffer, were purchased from Sigma. All the other
(WHO) and the European Union (EU) have established a maximum reagents were analytical grade.
of 250 mg/kg for 4-MeI, for caramels class III and IV, and a limit of Ultrahigh purity He (helium) for GC–MS and N2 (nitrogen) for
10 mg/kg for THI for caramels class III (WHO, 1971; Document III/ solvent evaporation were obtained from Gasin (Maia, Portugal).
5218/94-EN-Rev, 1995). Until now, no limit levels have been
established for the presence of 4-MI in foodstuffs. Monitorization is 2.2. Standards
nevertheless necessary in order to ensure that the caramel added
to the foods and beverages are declared in the label, to estimate the A stock solution of 4-MeI (2 g/L) was prepared by dissolving the
levels of caramel added, and to guarantee that human dietary compound in 0.1 M HCI. An intermediate standard solution (2 mg/
intakes are within acceptable levels. L) was prepared from the stock solution by appropriate dilution in
Several methods have been developed to determine 4-MeI 0.1 M HCI. A working 1 g/L solution of the 2-EI used as internal
based on thin layer chromatography (TLC) (Rabe et al., 1988), standard (I.S.) was also prepared in 0.1 M HCI. All the solutions
fluorimetry (Gutierrez et al., 1986), capillary electrophoresis (Ong were kept at 4 8C when not in use. Linearity was studied using
et al., 1994) or high performance liquid chromatography (HPLC) matrix-matched calibration by analyzing blank samples (free of 4-
coupled with ultraviolet light (UV) (Thomsen and Willumsen, MeI) spiked at six concentration levels, in order to obtain
1981; Coffey et al., 1997). However, these methods require a labor- concentrations ranging from 20 to 750 mg/L. The concentration
and time-consuming sample pre-treatment and have poor of the samples was obtained by the internal standard method.
sensitivity. In recent years more sensitive methods have been
published, based mainly on mass spectrometry (MS) as a detection 2.3. Sampling
technique, coupled with a chromatographic step either by liquid
´
chromatography (LC) (Klejdus et al., 2003, 2006; Lojkova et al., A total of 30 samples of soft drinks comprising 16 colas, 8
2006) or gas chromatography (GC), the latter after derivatization of energy drinks, 6 uncarbonated flavor drinks and 1 carbonated
the analytes (Fernandes and Ferreira, 1997; Casal et al., 2002). The guarana were randomly purchased in local supermarkets. A total of
main advantage of the recent LC–MS methods proposed by the 2 colas were acquired in supermarkets in Spain and 3 colas and 1
´
group of Kuban is the possibility to analyze simultaneously 4-MeI energy drink were obtained in supermarkets in France. A total of 20
and THI without derivatization (Klejdus et al., 2003, 2006; Lojkova ´ samples of dark beers were also purchased in local supermarkets.
et al., 2006). Notwithstanding the high selectivity achieved by this All the samples were stored at room temperature (Æ20 8C)
technique, the methods include a previous tedious solid-phase protected from light and opened only on the moment of analysis.
extraction (Klejdus et al., 2006) or supercritical fluid extraction
´
(Lojkova et al., 2006). 2.4. Sample preparation
The use of GC–MS methods based on ion pair-extraction with
bis-2-ethylhexilphosphate (BEHPA) and isobutylchloroformate 2.4.1. Ion-pair extraction and derivatization of 4-MeI
derivatization has been successfully applied for determination of 4-MeI was extracted from the samples using a procedure based
4-MeI at trace levels in caramel and coffee (Fernandes and Ferreira, on a previously described methodology (Fernandes and Ferreira,
1997; Casal et al., 2002). The application of this method to other 1997) with some modifications; the analysis scheme is shown in
matrices seems of great interest because of the selectivity and Fig. 1. An aliquot of 25 mL of homogenated sample added with
sensibility obtained. However, some problems related to degrada- 50 mL 2-EI (I.S.) at 1 g/L was introduced in a 50 mL glass centrifuge
tion of the columns following injection of chloroformic extracts ¨
tube and concentrated in a Buchi Rotavapor model RE 111 with a
containing excess of isobutylchloroformate (Casal et al., 2002; 461 water bath (Flawil, Switzerland) at 60 8C, to about 5 mL (Fig. 1).
Fernandes et al., 2001) have prevented widespread application to Then, 1 mL of the sample concentrate was placed into a mL vial,
other matrices. and the pH of the mixture adjusted to 6.6 by drop-wise addition of
The main objectives of this work were: (i) to improve some concentrated potassium hydroxide solution followed by addition
features of the previously developed method, based on ion-pair of 1 mL of phosphate buffer. The mixture was extracted with 2 mL
extraction with isobutylchloroformate derivatization and GC–MS of 0.1 M BEHPA in chloroform, through hand mixing for 1 min and
analysis, to increase its ruggedness and reliability when applied to vortexing for 2 min. After a centrifugation step at 5000 rpm for
other food matrices; (ii) to conduct a survey on the presence of 4- 5 min, a 1.8 mL portion of the chloroform phase (bottom layer) was
MeI in soft drinks and dark beer samples; and (iii) to assess the 4- further removed to a second vial which contained 1.0 mL of 0.1 M
MeI intake from European and American consumers, based on 4- HCI. The mixture was again mixed by hand for 1 min and
MeI levels obtained from soft drinks and the available consump- centrifuged at 5000 rpm for 1 min. Then, a 250 mL aliquot of the
tion data. aqueous phase (upon layer) was transferred to a reaction vial and
derivatized with a 250 mL of MeCN–isobutanol–pyridine
2. Materials and methods (50:30:20, v/v) and 30 mL (15 + 15 mL) of IBCF through a brief
shaking (15–30 s). Finally, 500 mL of a 1.0 M aqueous sodium
2.1. Reagents and solutions bicarbonate solution and 500 mL of isooctane were added into the
mixture and after a brief shake of 4–5 s, the bottom layer was
4-(5-)Methylimidazole (purity ! 99%) and 2-ethylimidazole (2- transferred to an autosampler vial and 2 mL were injected into the
EI, purity ! 98%) were purchased from Sigma (West Chester, PA; GC–MS system.
USA) and from Aldrich (Steinheim, Germany), respectively. Bis-2-
ethylhexylphosphate (BEHPA; purity ! 98%) was from Aldrich and 2.4.2. Apparatus and GC–MS conditions
isobutylchloroformate (IBCF; purity ! 99%) was purchased from The determination of 4-MeI was performed on an Agilent (Little
Sigma. Isooctane and acetonitrile (MeCN) both of LiChrosolv Falls, DE, USA) gas chromatograph 6890 equipped with an
quality were purchased from Merck (Darmstadt, Germany). electronically controlled split/splitless injection port, an inert
Pyridine (over molecular sieve, purity > 99.8%), acetic acid 5975B mass selective detector with electron impact (EI) ionization
(purity > 99.7%) and isobutanol (purity > 99.8%) were purchased chamber, and a 7683B Series injector/autosampler.
from Fluka (Neu-Ulm, Germany). Potassium dihydrogen phos- The GC separation was conducted with a DB-5ms column
phate and dipotassium hydrogen phosphate, used to prepare (15 m  0.25 mm I.D.  0.25 mm film thickness; J&W Scientific,
3. S.C. Cunha et al. / Journal of Food Composition and Analysis 24 (2011) 609–614 611
Fig. 1. Sample preparation scheme used in this study.
Folsom, CA, USA). Helium was the carrier gas with a constant 4-MeI from ammonia caramel colors (Thomsen and Willumsen,
pressure of 80 kPa. The injection was made in splitless mode at 1981; Fernandes and Ferreira, 1997), and coffees (Casal et al.,
270 8C. The oven temperature program was as follows: 80 8C held 2002), using BEHPA as ion-pair reagent and chloroform as organic
for 1.0 min, ramped to 280 8C at 30 8C/min and held for 1.83 min. solvent. The procedure proved to be quite selective and effective in
The MS transfer line temperature was held at 280 8C. Total run time the extraction of 4-MeI and similar imidazolic compounds from
was 9.5 min. complex matrices. Given the low amounts of 4-MeI expected in the
Mass spectrometric parameters were set as follows: electron samples under study, a previous concentration step was
impact ionization with 70 eV energy; ion source temperature, performed, in order to improve detection and quantification limits.
230 8C; MS quadrupole temperature, 150 8C and solvent delay, The 4-MeI extracted by ion-pair was then acylated with IBCF in
2 min. The MS system was routinely set in selective ion monitoring presence of the acetonitrile–isobutanol–pyridine mixture, in order
(SIM) mode and 4-MeI was quantified based on peak area using to improve the thermal stability of the analyte and its chro-
one target and three qualifier ion(s). Complete SIM parameters and matographic behavior. The derivatives were subsequently
retention times of the analytes are shown in Table 1. Agilent extracted with isooctane instead of chloroform used in the
Chemstation was used for data collection/processing and GC–MS previous works. The use of isooctane totally solved the problems
control. of rapid deterioration of chromatographic performance (pro-
nounced tailing and gradual decrease in peak areas) that was
2.5. Statistical analysis previously verified after several injections of IBCF derivatives in
chloroform in similar DB-5 MS columns (Fernandes et al., 2001;
The analysis was carried out with SPSS for Windows 17.0 (SPSS Casal et al., 2002). After more than 300 injections made with
Corporation, Chicago, IL). Kolmogorov–Smirnov test was used to standard and sample extracts in the same column no visible
verify parametric or nonparametric characteristic of data. To degradation of the peaks shape and peaks area was observed. The
evaluate the difference between samples a nonparametric test use of a short capillary column (15 m) allowed the reduction of
(Mann–Whitney U-test) was chosen due to sample size and non- retention times corresponding to the peaks of interest into about
normal distribution. Statistical significance was assumed if a null 4 min when compared with our previous works, without lost of
hypothesis could be rejected at p < 0.05. resolution or sensibility.
Fig. 2 shows a chromatogram of 4-MeI standard at 250 mg/L and
3. Results and discussion a positive sample with 399 mg/L of 4-MeI obtained using the
described procedure. As observed two peaks corresponding to 4-
3.1. Optimization of sample preparation and chromatographic MeI (a and b) were detected. This observation was valid either for
conditions for analysis of 4-MeI standards or samples and it was already described by Fernandes
and Ferreira (1997). It is probably due to the natural tautomerism
Ion-pair extraction provides the extraction of ionizable characteristic of substituted imidazoles (Worth et al., 1989;
compounds into an organic phase as an ion-pair by addition of a Hasegawa et al., 2000). This was, however, no constraint for a
suitable ion with opposite charge (Carson, 2000). An ion-pair correct quantification of the compound, since the sum of peak
extraction procedure has been successfully applied in extraction of areas was used.
Table 1
MS conditions for 4-[5-]methylimidazole [(4-)MeI] and internal standard (I.S.) analysis (start times of windows and ions selected in SIM mode, quantification ions in bold).
Compounds tR (min) Time windows Data acquisition SIM ions
(min) rate (scans/s) (m/z)
4-MeI (a) 3.42 182, 82, 109, 81
4-MeI (b) 3.72 2.0–9.5 3.75 182, 82, 68, 81
2-EI (I.S.) 3.76 196, 95, 123, 81
4. 612 S.C. Cunha et al. / Journal of Food Composition and Analysis 24 (2011) 609–614
Abundance
A
2-EI
130000
110000
90000
70000
50000
4-MeI(a)
30000
I(b)
4
4-MeI
10000
0
2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 7.50 8.00 8.50 9.00
Time (min)
130000
2-EI
110000 B
90000
70000
50000
4-MeI(a)
MeI(b)
30000
4-M
10000
0
2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 7.50 8.00 8.50 9.00 Time (min)
Fig. 2. Chromatograms in SIM mode of a spiked blank soft drink [250 mg/L of 4-MeI (total a and b) and 1 mg/L of I.S. (2-EI)] and a positive generic cola sample [399 mg/L of 4-
MeI (total a and b) and 1 mg/L of I.S. (2-EI)] obtained by the optimized GC/MS method. Ion 182 for 4-MeI (a and b) and ion 196 for 2-EI.
3.2. Method performance test performed six times, as described in Section 2. As shown in Table
2 the average of recoveries ranging from 90 to 101%. The precision
3.2.1. Linearity measured by the relative standard deviation (RSD) ranging from 3 to
The possible matrix effect on the chromatographic response 8%. The results reported provide evidence that the optimized
was preliminary assayed. Therefore the slopes of the calibration method guarantees that 4-MeI can be properly quantified.
curves obtained from aqueous standard solutions were compared
with those obtained in matrix-matched standards (standards 3.2.3. Limit of detection (LOD) and limit of quantification (LOQ)
added to blank samples). The slopes values were 0.3185 for the The LOD of the method was determined by successive analyses
aqueous solutions and 1.0170 and 1.0478 for soft drinks and beer, of chromatographic sample extracts with decreasing amounts of
respectively. This enhancement response for 4-MeI was observed the compounds until a 3:1 signal-to-noise ratio was reached,
previously for other analytes in distinct kind of matrices (Cunha whereas the LOQ was determined considering a signal-to-noise
et al., 2009; Poole, 2008). It can be related with the properties of the ratio 10:1. In this study because the quantification was made with
analyte itself as well as the presence of other ionizable compounds the sum of the peak areas of 4-MeI (a) and 4-MeI (b), the size of the
present in the extract. Although the slope between both matrices latter was the limiting factor. The LOD and LOQ were 0.60 mg/L and
are not statistically different (p > 0.05) indicating that the selected 2.2 mg/L, respectively. These values are lower than those reported
matrices do not have any significant influence on the extraction in the previous paper for caramel (Fernandes and Ferreira, 1997).
procedure, matrix-matched calibration solutions of either blank
soft-drinks and blank beers were used for quantification purposes. 3.3. Analysis of 4-MeI in soft drinks and dark beers
Thus the linearity of the method was several times tested using the
referred matrix-matched calibration solutions with six concentra- The content of 4-MeI in various soft drinks (white and brand-
tions (20, 50, 100, 250, 500 and 750 mg/L), prepared as described in name colas, energy drinks and uncarbonated flavor) was determined
Section 2. Calibration curves were constructed by plotting the
analyte/I.S. peak areas ratio obtained against the concentration
Table 2
values. The results obtained had a quite good linearity with
Average recoveries (%) and precision (%RSD, relative standard deviation) obtained in
correlation coefficients always higher than 0.998 in the two spiked soft drink samples using the developed method.
distinct matrices studied.
Level added (mg/L) Recovery (%) Precision (%RSD)
3.2.2. Recovery and precision 50 101 8
250 90 5
Recovery and precision were determined on blank samples of soft
750 92 3
drinks spiked with 4-MeI at three concentration levels, being each
5. S.C. Cunha et al. / Journal of Food Composition and Analysis 24 (2011) 609–614 613
Table 3 Table 4
Level of 4-[5-]methylimidazole [(4-)MeI] (average and % relative standard deviation Level of 4-[5-]methylimidazole [(4-)MeI] (average and % relative standard deviation
n = 2) in soft drinks and difference between the types of samples analyzed. n = 2) in dark beers and difference between the types of samples analyzed.
Type Geographic Label 4-MeI Type Geographic Label 4-MeI
origin information mg/L (%RSD) origin information mg/L (%RSD)
Brand colaa,b Portugal E150d 248 (1) Lager-Darka Portugal Caramel 325 (1)
E150d 228 (2) – 170 (2)
E150d 249 (1) – 172 (2)
E150d 340 (1) – 77 (3)
E150d 243 (2) – n.d.
E150d 287 (1) – n.d.
E150d 214 (2) Spain – 8 (10)
E150d 372 (1) Germany – 3 (9)
E150d 360 (1) – 39 (4)
Spain E150d 416 (1) – n.d.
E150d 270 (1) Ales-trappista Belgium – 20 (7)
France E150d 188 (2) – 150 (2)
E150d 333 (1) – 424 (1)
White label colab France E150d 219 (2) Ales-stouta Irland – 21 (7)
Portugal E150d 454 (1) – 18 (8)
E150d 305 (1) Portugal E150c 140 (2)
E150d 255 (1) Caramel 142 (2)
E150d 430 (1) Weissbier-darka Germany – n.d.
E150d 399 (1) – n.d.
Caramel 406 (1) – 3(8)
E150d 613 (1)
–: not mentioned; n.d.: not detected. E150C (ammonia caramel).
Energy drinka Portugal Caramel n.d.
Caramel n.d.
E150b n.d.
E150d n.d.
previously reported for carbonated beverage by Fernandes et al.
E150d n.d.
E150d n.d. (1997).
E150d 37 (12) Results found for 4-MeI in dark beers samples are summarized
France Caramel n.d. in Table 4, as well as all important information reported in the
Carbonated guaranab Portugal E150d 438 (2)
labels. The 4-MeI was found in 15 of the 20 samples analyzed, with
No carbonated flavora,b Portugal E150d 43 (10)
E150d 42 (8)
great variation. Some were either free from or had a negligible
E150d 71 (6) amount of 4-MeI the levels ranging from 3 to 424 mg/L. However,
– n.d. the addition of caramel color during the brewing process is not
Caramel n.d. generally mentioned in the label (see Table 4). The concentrations
E150d n.d.
found in this study were higher than those reported by Klejdus
–: not mentioned; n.d.: not detected. a,bMeans in groups without common letters et al. (2006), with levels ranged from 1.6 to 28 mg/L. This
are significantly different (p < 0.05). E150d (sulfite ammonia caramel).
discrepancy may be partly attributed to the origin and number
of the samples analyzed. Concerning the influence of the beer type
in the 4-MeI content, no significant (p > 0.05) differences were
in duplicate following the methodology described. The results found between the samples belonging to the four beer categories.
obtained and the relevant information reported in the label of each
sample analyzed are shown in Table 3. 4-MeI was found in 26 of 36 3.4. Exposure to 4-MeI via ingestion
soft drinks analyzed, being the levels found extremely variable,
ranging from 37 to 613 mg/L. The higher values were found in It is known that the human exposure to 4-MeI may have
generic colas, with levels ranging from 219 to 613 mg/L, a mean of adverse health outcomes, e.g. neurotoxic effects (Patey et al., 1985;
385 mg/L (n = 8). Brand-name colas presented slightly lower levels, ´
Delgado-Vargas and Paredes-Lopez, 2003). This fact assumes
ranging from 188 to 416 mg/L, with a mean of 288 mg/L (n = 13). The particular importance taking in consideration the steady rise of
4-MeI contents in brand-name colas were slightly lower than those soft drink consumption in the recent last years worldwide. The
reported by our group ten years ago for similar samples, with levels major consumption of soft drinks in the world occurs in the USA,
ranging from 380 to 715 mg/L, in 10 similar samples (Fernandes with 216 L/year per capita in 2002, comparing with 204 L/year per
et al., 1997). The difference found between both studies can be capita in 1999 (Hawkes, 2002), with colas representing more than
justified by the number of samples analyzed and probably by the 70%. In what concern Western Europe the consumption of soft
improvements that naturally have taken place at the level of process drinks was only 83.2 L/year per capita in 1999 (Hawkes, 2002).
and control systems to guarantee the quality and safety of the final European statistics from a different source referring to 2002
product. Regarding the geographical origin of the colas no significant (Hawkes, 2002) show identical whole values, although with large
differences were found between the samples of the three countries variations between different countries, from 126 L/year per capita
analyzed, suggesting that colas technological process is not in Ireland to 37.2 L/year per capita in France (http://www.nation-
considerably different. master.com).
On the contrary to what was verified in colas samples where Preliminary assessment of consumer’s exposure to 4-MeI in soft
all samples were positive, in the energy drinks only 1 of 8 drinks was calculated by the estimated daily intake (EDI). The EDI
samples analyzed shown 4-MeI, in a concentration of 37 mg/L. expressed in mg/kg body weight/day was obtained as the result of
The carbonated guarana present a value of 4-MeI (438 mg/L) the soft drink consuming plus the maximum amount of 4-MeI
near of the colas, even though presenting lower color intensity found in soft drinks (613 mg/L). The consumption values consid-
from a visual point of view. To the uncarbonated flavor drinks, 4- ered were the mentioned above for 1999, and a human body
MeI was found in 3 of 6 samples analyzed, with levels ranging weight of 60 kg was assumed. The estimated daily intake of 4-MeI
from 42 to 71 mg/L. These results are in accordance with those in Europe was 2.3 mg/kg body weight/day and 5.7 mg/kg body
6. 614 S.C. Cunha et al. / Journal of Food Composition and Analysis 24 (2011) 609–614
weight/day in USA for soft drinks. The total human daily intake of pesticides in grapes, musts and wines. Journal of Chromatography A 1216,
119–126.
4-MeI is obviously higher because other sources of the compound ´
Delgado-Vargas, F., Paredes-Lopez, O., 2003. Natural Colorants for Food and Nutra-
should be considered (baked goods, confectionery, extruded ceutical Uses. CRC Press LLC, New York, USA (Chapter 4).
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June 1995.
It is difficult to compare the results obtained here with those Fernandes, J.O., Ferreira, M.A., 1997. Gas chromatographic–mass spectrometric
of other monitoring programs from other countries, because determination of 4-(5) methylimidazole in ammonia caramel colour using
they are scarce and mostly outdated. Furthermore, the only ion-pair extraction and derivatization with isobutylchloroformate. Journal of
Chromatography A 786, 299–308.
acceptable daily intake (ADI) established for 4-MEI by WHO is Fernandes, J.O., Faria, M.A.R.P., Ferreira, M.A., 1997. Quantification of 4-(5-) methy-
for caramel colors produced by ammonia process (0–100 mg/kg limidazole in colas and other carbonated beverages. In: Proceedings of 16th
body weight/day). ´ ´
International Congress of Nutrition, Montreal, Quebec, Canada, p. 356.
Fernandes, J.O., Judas, I.C., Oliveira, M.B., Ferreira, I.M.P.L.V.O., Ferreira, M.A., 2001. A
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Gutierrez, M.C., Gomez-Hens, A., Valcarcel, M., 1986. Individual and joint kinetic
A modified method was evaluated for determination of 4-MeI in fluorimetric determination of imidazole and 4-methylimidazole. Microchem-
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soft drinks and dark beers. The proposed method based on ion-pair Hargreaves, M.B., Jones, B.C., Smith, D.A., Gescher, A., 1994. Inhibition of p-nitro-
extraction, acylation with isobutylchloroformate and GC–MS phenol hydroxylase in rat liver microsomes by small aromatic and heterocyclic
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Hasegawa, K., Ono, T., Noguchi, T., 2000. Vibrational spectra and ab initio DFT
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sensibility. The method was used for a survey on the presence of 4- and Raman markers of the protonation state of a histidine side chain. Journal
MeI in several types of soft-drinks (colas, carbonated and Physical Chemistry B 104, 4253–4265.
Hawkes, C., 2002. Marketing activities of global soft drink and fast food companies.
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only one of 8 energy drinks analyzed was positive for 4-MeI. Based
´ ´
Klejdus, B., Moravcova, J., Kuban, V., 2003. Reversed-phase high-performance liquid
only on cola consumption, the mean per capita daily intake of 4- chromatographic/mass spectrometric method for separation of 4-methylimi-
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in Europe and USA, respectively. These values vary widely lytica Chimica Acta 477, 49–58.
´ ´ ´
Klejdus, B., Moravcova, J., Lojkova, L., Vacek, J., Kuban, V., 2006. Solid-phase
according to individual consumer habits, and in some cases they extraction of 4(5)-methylimidazole (4MeI) and 2-acetyl-4(5)-(1,2,3,4-tetrahy-
probably reach levels of concern for human health. droxybutyl)-imidazole (THI) from foods and beverages with subsequent liquid
chromatographic–electrospray mass spectrometric quantification. Journal of
Separation Science 29, 378–384.
Acknowledgments ´ ´ ´
Lojkova, L., Klejdus, B., Moravcova, J., Kuban, V., 2006. Supercritical fluid extraction
(SFE) of 4(5)-methylimidazole (4-MeI) and 2-acetyl-4(5)-(1,2,3,4)-tetrahydrox-
This research was supported by grant from the FCT project ybutyl-imidazole (THI) from ground-coffee with high-performance liquid chro-
matographic–electrospray mass spectrometric quantification (HPLC/ESI-MS).
‘‘PTDC/AGR-ALI/101583/2008’’ and COMPETE FSE/FEDER. S.C.C. is Food Additives and Contaminants 23, 963–973.
grateful to ‘‘POPH-QREN-Tipologia 4.2, Fundo Social Europeu e Ong, C.P., Ng, C.L., Lee, H.K., Li, S.F.Y., 1994. Separation of imidazole and its
Fundo Nacional MCTES’’. M.A. Faria is grateful to FCT for the Grant derivatives by capillary electrophoresis. Journal of Chromatography A 686,
319–324.
SFRH/BPD/20725/2004.
Patey, A.L., Shearer, G., Knowles, M.E., Denner, W.H.B., 1985. Ammonia caramels:
specifications and analysis. Food Additives and Contaminants 2, 107–112.
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