Optimizing ozone treatment for pathogen removal and disinfection by-product control for potable reuse at pilot-scale.

Reclaimed water poses environmental and human health risks due to residual organic micropollutants and pathogens. Ozonation of reclaimed water to control pathogens and trace organics is an important step in advanced water treatment systems for potable reuse of reclaimed water. Ensuring efficient pathogen reduction while controlling disinfection byproducts remains a significant challenge to implementing ozonation in reclaimed water reuse applications. This study aimed to investigate ozonation conditions using a plug flow reactor (PFR) to achieve effective pathogen removal/inactivation while minimizing bromate and N-Nitrosodimethylamine (NDMA) formation. The pilot scale study was conducted using three doses of ozone (0.7, 1.0 and 1.4 ozone/total organic carbon (O3/TOC) ratio) to determine the disinfection performance using actual reclaimed water. The disinfection efficiency was assessed by measuring total coliforms, Escherichia coli (E. coli), Pepper Mild Mottle Virus (PMMoV), Tomato Brown Rugose Fruit Virus (ToBRFV) and Norovirus (HNoV). The ozone CT values ranged from 1.60 to 13.62 mg min L-1, resulting in significant reductions in pathogens and indicators. Specifically, ozone treatment led to concentration reductions of 2.46-2.89, 2.03-2.18, 0.46-1.63, 2.23-2.64 and > 4 log for total coliforms, E. coli, PMMoV, ToBRFV, and HNoV, respectively. After ozonation, concentrations of bromate and NDMA increased, reaching levels between 2.8 and 12.0 µg L-1, and 28-40.0 ng L-1, respectively, for average feed water bromide levels of 86.7 ± 1.8 µg L-1 and TOC levels of 7.2 ± 0.1 mg L-1. The increases in DBP formation were pronounced with higher ozone dosages, possibly requiring removal/control in subsequent treatment steps in some potable reuse applications.

Determinación de bromato de potasio en panes expedidos en supermercados de la ciudad de La Paz-gestión 2019 / Determination of potassium bromate in breads issued in supermarkets in the city of La Paz-gestión 2019

INTRODUCCIÓN: el bromato de potasio es una sustancia mejoradora del pan que actualmente está prohibida para su uso en la elaboración del pan porque se considera nociva para el ser humano, produciendo principalmente daños gastrointestinales. Es así que los organismos de control de alimentos prohíben su uso completamente, al igual que la NB 39007:2012 harina y derivados-productos panificados-requisitos en su tercera revisión, en nuestro país. OBJETIVO: determinar la presencia del bromato de potasio en panes expedidos en supermercados de la ciudad de La Paz. MÉTODOS: el método cualitativo para Bromatos /Yodatos y el método indirecto con el reactivo fucsina bisulfito fueron los métodos oficiales aplicados para la determinación de bromato de potasio. RESULTADOS: el porcentaje de muestras de un total de 13 panes, con presencia de bromatos es de 15,38 %, lo que demuestra que el control realizado por los entes oficiales de control ha ido aumentando en la última gestión, sin embargo, llama la atención que aún se encuentre la presencia de bromato de potasio, siendo que es un aditivo de uso prohibido en nuestro país. CONCLUSIONES: comparando los métodos estandarizados para el estudio, el método cualitativo para bromatos /yodatos presenta mayor eficacia que el método indirecto con el reactivo fucsina bisulfito. Al encontrar un porcentaje de panes que contiene bromato de potasio, verificamos que los controles por los entes oficiales no se realizan constantemente o no quedan registrados.

INTRODUCTION: potassium bromate is a bread improving substance that is currently prohibited for use in making bread because it is considered harmful to humans, mainly causing gastrointestinal damage. Thus, the food control bodies prohibit its use completely, as well as NB 39007: 2012 flour and derivatives-baked products-requirements in its third revision, in our country. OBJECTIVE: to determine the presence of potassium bromate in breads shipped in supermarkets in the city of La Paz. METHODS: the qualitative method for bromates/Iodates and the Indirect. Method with the fuchsin bisulfite reagent were the official methods applied for the determination of potassium bromate. RESULTS: the percentage of samples from a total of 13 breads, with the presence of bromates is 15.38%, which shows that the control carried out by the official control entities has been increasing in the last administration, however, calls the attention that the presence of potassium bromate is still found, since it is an additive forbidden in our country. CONCLUSIONS: comparing the standardized methods for the study, the Qualitative Method for Bromates / Iodates presents greater efficiency than the indirect method with the fuchsin bisulfite reagent. By finding a percentage of bread that contains potassium bromate, we verify that the controls by official entities are not carried out constantly or are not recorded.

Occurrence and human exposure to bromate via drinking water, fruits and vegetables in Chile.

Bromate (BrO3-) is an anionic contaminant known possess carcinogenic potential. Although some studies have reported the occurrence of bromate in drinking water, very little is known about its presence in fruits and vegetables, especially in Chile. In this study, we quantified bromate in soils (n = 29), drinking water (n = 43), surface water (n = 6), groundwater (n = 6), fertilizers (n = 7), fruits (n = 12) and vegetables (n = 42) collected across Chile. The highest average concentrations of bromate in soils (11.7 ng g-1) and drinking water (8.8 ng mL-1) were found in northern Chile. Additionally, drinking water collected from four regions of Chile showed higher concentrations of bromate (median:18.5 ng mL-1) than the maximum contaminant level (MCL, 10 ng mL-1). Concentrations of bromate in nitrogenous and non-nitrogenous fertilizers were similar (median: 2.51 µg g-1). Leafy vegetables (median: 9.52 ng g-1) produced in the northern Chile contained higher bromate concentrations than those produced in other regions (median: 0.24 ng g-1). The estimated daily intakes of bromate via drinking water in northern, central and southern were ranged between 58.6 and 447 ng/kg bw/d. Leafy vegetables were an important source of bromate for all age group. The EDI values were below the respective reference dose (RfD) of 4000 ng/kg-day.

Análise da presença de bromato de potássio em pães produzidos e comercializados em panificadoras do município de Mossoró: RN

O pão é um dos alimentos mais difundidos e se constitui em uma das principais fontes calóricas da dieta do brasileiro. Ao longo do tempo o pão foi se aperfeiçoado, ganhou novas formulações e processos, adaptando-se às culturas e necessidades do homem. Os avanços tecnológicos permitiram a substituição ou a agregação de aditivos em busca de uma melhor qualidade. A utilização do bromato de potássio como aditivo alimentar na indústria de panificação tem sido praticada desde o início do século como uma mistura de sais melhoradores de pães. No entanto, foram evidenciados efeitos danosos à saúde em animais de laboratório. Portanto, diante do grande consumo de pão francês e o potencial risco carcinogênico neste, o presente trabalho teve como objetivo determinar a presença de bromato de potássio em pães franceses, produzidos e comercializados em panificadoras da cidade de Mossoró - RN. Para isto foram coletadas 30 amostras de pães franceses de diferentes panificadoras no período de outubro a novembro de 2014. As amostras coletadas foram transportadas sob condições assépticas para o Laboratório de Alimentos da Universidade Potiguar -UNP, campus Mossoró, onde foram analisadas. Com o resultado pode-se observar que das trinta amostras coletadas nas padarias 60% deram positivo para análise qualitativa de bromato e 40% deram negativo. Portanto, há a necessidade de um efetivo controle dos estabelecimentos que produzem e comercializam este tipo de produto, cabendo à vigilância sanitária garantir o cumprimento da legislação vigente.(AU)

Currently the bakery segment in Brazil is composed mostly of small and medium companies, representing approximately 95% overall, including patisseries, bakeries being responsible for 85% of the bakery market in Brazil. Raw material of bread, wheat, cereal is greater acceptance of the most consumed worldwide, and wheat, which has greater acceptance. Bread is one of the most widespread food and constitutes one of the main caloric sources of the Brazilian diet. The annual per capita consumption of French bread is 18,4 kg, second only to the polished rice, which is 26,5 kg. Over time the bread was perfect, he gained new forms, formulations and processes, adapting to the culture and needs of man. Technological advances have allowed the substitution or addition of additives in search of a better quality. The main food additives are used in baking emulsifiers, oxidising agents, acidity regulators and stabilizers. The use of potassium bromate as a food additive in the baking industry has been practiced since the beginning oft he century, was the first patent filed in 1915, as a mixture of salts of bread improvers. However, were shown adverse health effects in laboratory animals. Therefore, before the great French bread consumption and the potential carcinogenic risk in consumption, this study aims to determine the presence of potassium bromate in bread French, produced and sold in bakeries in town of Mossley - RN.(AU)

Avaliação da contaminação por bromato em pães do tipo francês / Analysis on the occurrence of bromate contamination in French type bread

O setor de panificação no Brasil tem realizado esforços para acompanhar as tendências de um mercadoexigente e competitivo, e uma das alternativas tem sido os agentes oxidantes. O bromato de potássio(KBrO3) é um agente oxidante que fortalece as cadeias de glúten. Apesar de benefícios tecnológicose econômicos, sua toxicidade como aditivo alimentar tem sido demonstrada. No Brasil o emprego doKBrO3 é proibido em qualquer quantidade nas farinhas e nos produtos de panificação. Foram investigadasamostras de pão Francês provenientes de 25 pontos comerciais, que foram analisadas em triplicatas,totalizando-se 75 ensaios. A determinação de bromatos foi realizada em duas etapas: primeiramente pelaprova de triagem utilizando-se o método analítico qualitativo, para identificar amostras positivas paraagentes oxidantes e, posteriormente, a determinação de BrO3- usando o reativo fucsina-bissulfito. Em todasas amostras foram detectados agentes oxidantes. Na análise confirmatória de bromato, foi identificadaa presença deste aditivo em amostras de seis estabelecimentos dos 25 analisados, correspondendo àfrequência de 24 % nas amostras examinadas. Este estudo mostra que apesar da proibição do emprego deKBrO3 em produtos de panificação, há ainda o uso deste componente pelos estabelecimentos comerciais,e isto representa risco à saúde da população...

Analysis on the occurrence of bromate contamination in French type bread / Avaliação da contaminação por bromato em pães do tipo francês

Bread-making sector in Brazil has been doing efforts in order to follow the trends of a demanding and competitive market, and the use of additives (oxidizing agents) has been one alternative. Bromate potassium (KBrO3 ) is an oxidizing agent that enhances the gluten chains. Despite their technological and economical benefits, the toxicity of this product has been demonstrated when used as a food additive. In Brazil the addition of KBrO3 in flour and bakery products is prohibited, in any amount. The French-type bread samples collected from 25 commercial spots were analyzed in triplicates, being in total 75 trials. The bromate detection was performed in two steps: firstly a screening test by using a qualitative analytical method for identifying the oxidizing agents-positive samples; and subsequently the determination of BrO3 using the fuchsin-bisulfite reagent. This component was found in all of the analyzed samples. The confirmatory analysis identified bromate occurrence in samples from six of 25 analyzed stores, corresponding to a frequency of 24 % of analyzed samples. In spite of the use of potassium bromate has been forbidden in bakeries, this additive has still been employed by bread factories, representing a risk to the population health.(AU)

O setor de panificação no Brasil tem realizado esforços para acompanhar as tendências de um mercado exigente e competitivo, e uma das alternativas tem sido os agentes oxidantes. O bromato de potássio (KBrO3 ) é um agente oxidante que fortalece as cadeias de glúten. Apesar de benefícios tecnológicos e econômicos, sua toxicidade como aditivo alimentar tem sido demonstrada. No Brasil o emprego do KBrO3 é proibido em qualquer quantidade nas farinhas e nos produtos de panificação. Foram investigadas amostras de pão Francês provenientes de 25 pontos comerciais, que foram analisadas em triplicatas, totalizando-se 75 ensaios. A determinação de bromatos foi realizada em duas etapas: primeiramente pela prova de triagem utilizando-se o método analítico qualitativo, para identificar amostras positivas para agentes oxidantes e, posteriormente, a determinação de BrO3 - usando o reativo fucsina-bissulfito. Em todas as amostras foram detectados agentes oxidantes. Na análise confirmatória de bromato, foi identificada a presença deste aditivo em amostras de seis estabelecimentos dos 25 analisados, correspondendo à frequência de 24 % nas amostras examinadas. Este estudo mostra que apesar da proibição do emprego de KBrO3 em produtos de panificação, há ainda o uso deste componente pelos estabelecimentos comerciais, e isto representa risco à saúde da população.(AU)

Inhibition of lysozyme by taurine dibromamine.

Hypobromous acid (HOBr) is a powerful oxidant produced by stimulated neutrophils and eosinophils. Taurine, a non-protein amino acid present in high amounts in the leukocytes, reacts instantaneously with HOBr leading to their haloamine derivative taurine dibromamine (Tau-NBr2). Lysozyme is a bactericidal enzyme also present in leukocytes and in secretory fluids. The inhibition of lysozyme is a pathway for bacterial proliferation in inflammatory sites. Here, we investigated the inhibition of the enzymatic activity of lysozyme when it was submitted to oxidation by Tau-NBr2. We found that the oxidation of lysozyme by Tau-NBr2 decreased its enzymatic activity in 80%, which was significant higher compared to the effect of its precursor HOBr (30%). The study and comparison of Tau-NBr2 and HOBr regarding the alterations provoked in the intrinsic fluorescence, synchronous fluorescence, resonance light scattering and near and far-UV circular dichroism spectra of lysozyme and oxidized lysozyme revealed that tryptophan residues in the active site of the protein were the main target for Tau-NBr2 and could explain its efficacy as inhibitor of lysozyme enzymatic activity. This property of Tau-NBr2 may have pathological significance, since it can be easily produced in the inflammatory sites.

Light emission from tryptophan oxidation by hypobromous acid.

The emission of ultraweak light from cells is a phenomenon associated with the oxidation of biomolecules by reactive oxygen species. The indole moiety present in tryptophan, serotonin and melatonin is frequently associated with the emission of light during the oxidation of these metabolites. This study presents results for hypobromous acid (HOBr) oxidation of tryptophan as a putative endogenous source of ultraweak light emission. We found that chemiluminescence elicited by the oxidation of tryptophan by HOBr was significantly higher than by hypochlorous acid (HOCl). This difference was related to secondary oxidation reactions, which were more intense using HOBr. The products identified during oxidation by HOCl, but depleted by using HOBr, were N-formylkynurenine, kynurenine, 1,2,3,3a,8,8a-hexahydro-3a-hydroxypyrrolo[2,3-b]-indole-2-carboxylic acid, oxindolylalanine and dioxindolylalanine. The emission of light is dependent on the free α-amino group of tryptophan, and hence, the indole of serotonin and melatonin, although efficiently oxidized, did not produce chemiluminescence. The emission of light was even greater using taurine monobromamine and dibromamine as the oxidant compared to HOBr. A mechanism based on bromine radical intermediates is suggested for the higher efficiency in light emission. Altogether, the experimental evidence described in the present study indicates that the oxidation of free tryptophan or tryptophan residues in proteins is an important source of ultraweak cellular emission of light. This light emission is increased in the presence of taurine, an amino acid present in large amounts in leukocytes, where this putative source of ultraweak light emission is even more relevant.

Pattern formation in the Belousov-Zhabotinsky-PAMAM dendrimer system.

The Belousov-Zhabotinsky reaction was studied under the influence of nanometric confinements induced by a complex polymer, the PAMAM-G4 dendrimers. They are well-defined in both molecular weight and architecture and are capable of molecular inclusion, making "unimolecular active micelles". The effect of such nanocompartments in the BZ reaction is analyzed by changing both the excitability and the concentration of the dendrimer, obtaining a wide range of behaviours, ranging from stationary Turing-like patterns to time dependent structures, such as jumping waves or packet waves.

Taurine bromamine: a potent oxidant of tryptophan residues in albumin.

Taurine is the most abundant free amino acid in leukocytes and can react with HOBr to produce taurine bromamine (Tau-NHBr). The aim of this study was to assess the ability of Tau-NHBr to oxidize tryptophan, either free or as a residue in albumin. We have demonstrated that Tau-NHBr is a powerful oxidant for tryptophan. Importantly, in comparison to taurine chloramine, HOCl or HOBr, Tau-NHBr exhibits a degree of selectivity for tryptophan. Oxidation of albumin by Tau-NHBr resulted in emission of light, and the quantum yield was more than 10-fold more efficient than that of the other oxidants. The fluorescence band corresponding to oxidized albumin (λ(ex) 350/λ(em) 450), which is characteristic of the formation of formylkynurenine, was significantly higher in reactions using Tau-NHBr. Excitation of the fluorescent probe 8-anilino-1-naphthalenesulfonate at 295 nm was used to assess the depletion of tryptophan residues in albumin. Results from this experiment further supported a higher efficiency of oxidation of tryptophan residues by Tau-NHBr. Other parameters of protein oxidation, including cysteine depletion and formation of carbonyl groups, were not significantly different between the oxidants tested. In conclusion, these results indicate that Tau-NHBr has a higher affinity for tryptophan residues in proteins.

Efecto citoprotector del camu-camu myrciaria dubia en tres líneas celulares de ratón expuestos in vivo a bromato de potasio / Effect cytoprotective camu-camu myrciaria dubia in three mouse cell lines exposed in vivo to potassium bromate

Se evaluó in vivo la capacidad citoprotectora del fruto de Myrciaria dubia (Kunth) McVaugh Camu-camu frente al daño mutagénico producido por bromato de potasio (68,5 mg/k) sobre tres líneas celulares de ratón (hígado, riñón y células sanguíneas). Se utilizó ratones (n= 120) divididos en tres grupos los cuales bebieron ad libitum: TI= control negativo (solo agua) y el grupo TIII (control positivo); El grupo TII bebió el extracto acuoso (2% p/v) del fruto de camu-camu. A los diez días se inyectó una dosis única de KBr03 (68,5 mg/kg peso corporal) vía intraperitoneal, a los grupos TII y TIII. El tratamiento con camu-camu continuo 35 días más, luego los ratones fueron eutanizados para determinar la frecuencia del daño al DNA mediante el protocolo del ensayo cometa alcalino. El grupo TII mostró en todas las líneas celulares el efecto citoprotector del camu-camu (p< 0,05). El efecto dañino al DNA por la acción oxidativa del KBrO3 es inhibido por el extracto acuoso del fruto de camu camu, probablemente por la presencia de los agentes antioxidantes como el Acido ascórbico y los flavonoides.

Photoelectrocatalytic removal of bromate using Ti/TiO2 coated as a photocathode.

These studies represent the rare use of a TiO2 material as a photocathode and the first application of photoelectrocatalysis for BrO3- removal. Photoelectrocatalytic reduction of BrO3- to Br- can reach 70% at neutral pH under an applied potential of -0.20 V versus SCE (saturated calomel electrode) after 75 min on the irradiated nanoporous thin-film TiO2-coated working electrode, which presented a flat band potential of -0.0274 V versus SCE. Regardless of the potential applied in these experiments, no BrO3- removal was observed in the counter electrode compartment or during electrolysis or photocatalysis, confirming that reduction of BrO3- to Br requires the combination of a negative potential (ideally near -0.20 V) and ultraviolet irradiation of the Ti/TiO2 electrode. The process was selective for BrO3- removal in that this process did not significantly reduce levels of Ca2+ and Mg2+ in drinking waters.

Bromato de potássio em aditivos para panificação usados em padarias do III Distrito Sanitário do Recife, PE – 2006 / Potassium bromate in bread additives used in bakeries III Distrito Sanitário do Recife, PE - 2006

Bromato de Potássio é um agente oxidante utilizado a panificação, porém no Brasil, através da Lei 10.273, de 05/09/2001, é proibido em farinhas, aditivos para panificação e produtos para panificação, considerando seus efeitos tóxicos à saúde, sendo classificado como carcinogênico. O presente trabalho objetiva identificar o atendimento à Lei acima citada, bem como relacionar o valor comercial do pão com o uso do bromato de potássio. (...)

Bromato de potássio em aditivos para panificação usados em padarias do III Distrito Sanitário do Recife, PE 2006 / Potassium bromate in bread additives used in bakeries III Distrito Sanitário do Recife, PE - 2006

Bromato de Potássio é um agente oxidante utilizado a panificação, porém no Brasil, através da Lei 10.273, de 05/09/2001, é proibido em farinhas, aditivos para panificação e produtos para panificação, considerando seus efeitos tóxicos à saúde, sendo classificado como carcinogênico. O presente trabalho objetiva identificar o atendimento à Lei acima citada, bem como relacionar o valor comercial do pão com o uso do bromato de potássio. Foram analisadas 29 amostras de melhoradores de panificação de padarias das Microregiões 3.1.2 e 3.2 do III Distrito Sanitário do Município do Recife, Pemambuco. O método por espectrofotometria foi usado para análise qualitativa, encontrando-se uma frequência de seis amostras, do tipo líquido, positivas para o bromato de potássio. Quatro padarias que utilizavam o produto comercializavam o pão por unidade e com uma média de 48,3% mais barato que aquelas que não faziam tal prática. Apesar da proibição, algumas panificadoras continuam a utilizar o produto, sem considerar os problemas que pode causar à saúdeda população, bem como sem atender à obrigatoriedade de comercialização do pão por quilograma. Assim, faz-se necessário continuar com programas de educação e fiscalização.(AU)

Potassium Bromate is an oxidant agent used in the bread baking industry, however in Brasil, according to law10.273 from Sept. 5, 2001, its use has been prohibited in flours and other bread baking products. Due to its harmfuleffects to human health, it is considered as carcinogenic. This research has the purpose to identify the complianceto the law aforementioned as well as to make a relation between the commercial costs of bread and the use of Potassium Bromate. It was analyzed 29 samples of dough conditioners in bakery shops in regions 3.1.2 and 3.2of the III Sanitary District of the City of Recife, Pemambuco. The spectrophotometric method was used for qualitative analysis, founding a frequency of positive samples to Potassium Bromate. Four bakery shops that used the Potassium Bromate used to sell their bread 48,3% cheaper than those that did not use the product. Despite theprohibition of Potassium Bromate, some bakery shops keep on using the product regardless the hazard it poses to public health as well as not abiding by the law, which clearly states that bread should be sold by weight. Therefore, the situation urges the implementation of law enforcement and educational programs as well. (AU)

Sensitive and rapid titrimetric and spectrophotometric methods for the determination of stavudine in pharmaceuticals using bromate-bromide and three dyes

Four sensitive and rapid methods for the determination of stavudine (STV) in bulk drug and in dosage forms were developed and optimized. In titrimetry, aqueous solution of STV was treated with a known excess of bromate-bromide in HCl medium followed by estimation of unreacted bromine by iodometric back titration. Spectrophotometric methods involve the addition of a measured excess of bromate-bromide in HCl medium and subsequent estimation of the residual bromine by reacting with a fixed amount of methyl orange, indigocarmine or thymol blue followed by measurement of absorbance at 520 nm (method A), 610 nm (method B) or 550 nm (method C). In all the methods, the amount of bromate reacted corresponds to the amount of STV. Calculations in titrimetry were based on a 1:0.666 (STV:KBrO3) stoichiometry and the method was found to be applicable over 3.5-10 mg range. A linear increase in absorbance with concentration of STV was observed in the spectrophotometric methods, and the Beer's law was obeyed over the concentration ranges 0.125-1.75, 1-10 and 1-9.0 µg mL-1 STV for method A, method B and method C, respectively. The methods when applied to the determination of STV in tablets and capsules were found to give satisfactory results.

Este trabalho descreve quatro métodos rápidos e sensíveispara a determinação de estavudina (STV) na matéria-prima ou em produtos formulados. Soluções aquosas de STV podem ser tituladas tratando-as com excesso de bromato-brometo em meio ácido clorídrico, seguido da determinação iodimétrica de bromo em excesso. Métodos espectrofotométricos tambémenvolvem a adição de excesso de bromato-brometo à amostra, seguida da determinação de bromo residual por adição de uma quantidade fixa de alaranjado de metila, índigo-carmim ou azul de timol, e de medidas de absorbância nos comprimentos de onda apropriados: 520, 610 ou 550 nm. Em todos os métodos, a quantidade de bromato consumida corresponde à quantidade de STV e os resultados da sua aplicação à determinação de STV em comprimidos e cápsulas são satisfatórios.

Sensitive and rapid titrimetric and spectrophotometric methods for the determination of stavudine in pharmaceuticals using bromate-bromide and three dyes.

Four sensitive and rapid methods for the determination of stavudine (STV) in bulk drug and in dosage forms were developed and optimized. In titrimetry, aqueous solution of STV was treated with a known excess of bromate-bromide in HCl medium followed by estimation of unreacted bromine by iodometric back titration. Spectrophotometric methods involve the addition of a measured excess of bromate-bromide in HCl medium and subsequent estimation of the residual bromine by reacting with a fixed amount of methyl orange, indigocarmine or thymol blue followed by measurement of absorbance at 520 nm (method A), 610 nm (method B) or 550 nm (method C). In all the methods, the amount of bromate reacted corresponds to the amount of STV. Calculations in titrimetry were based on a 1:0.666 (STV:KBrO3) stoichiometry and the method was found to be applicable over 3.5-10 mg range. A linear increase in absorbance with concentration of STV was observed in the spectrophotometric methods, and the Beer's law was obeyed over the concentration ranges 0.125-1.75, 1-10 and 1-9.0 microg mL-1 STV for method A, method B and method C, respectively. The methods when applied to the determination of STV in tablets and capsules were found to give satisfactory results.

Embriotoxicidad del bromato de potasio en raton (Mus musculus) / Potassium bromate embryotoxicity in mouse (Mus musculus)

Se evaluó in vivo los efectos de bromato de potasio (KBr03) sobre el desarrollo de embriones pre implantacionales de ratón. Ratonas preñadas fueron tratadas con una dosis única de KBr03 (68,5 mg/kg de peso corporal; n= 8) y un grupo control (C) tratado con agua destilada (n= 7) en el día1; al cuarto día de preñez, las hembras fueron sacrificadas, los embriones fueron extraidos de los oviductos y de los cuernos uterinos para la evaluación. El KBr03 produjo un retraso en el desarrollo embrionario, encontrándose un 76,9±7,8 y 11,2±5,5 en porcentaje de blastocistos y mórulas respectivamente en el C en comparación de un 34,8±11,2 y 49,3±11,9 de la misma relación en el grupo tratado, mostrando diferencias significativas(p0,05). En conclusión podemos decir que el KBr03 produce un efecto dañino sobre el embrión, causando retraso en su desarrollo.

The effect of potassium bromate (KBr03)on pre implantation mouse embryo development was evaluated in vivo. Pregnant mice were treated with unique dose of KBr03 (68,5 mg/kg of corporalweight; n= 8) and a control (C) provided with distilled water (n= 7) on day 1; at the fourth day ofpregnancy, females were sacrificed, embryos were flushed from oviducts and uterine horns for evaluation. KBr03 causes a delay in the embryonic development, 76,9±7,8 y 11,2±5,5 percent of blastocyst and morulaes respectively in the control group comparing with 34,8±11,2 y 49,3±11,9 percent of the same relation in the treated group, showing significative difference (p0,05). In conclusion we can say that KBr03 produces a harmful effect on the embryo causinga delay on its development.

Parâmetros bromatológicos e fermentativos das silagens de milho e girassol / Bromatological and fermentative parameters of corn and sunflower silages

Foi desenvolvido no Instituto de Zootecnia, Agência Paulista de Tecnologia dos Agronegócios (APTA), São Paulo um experimento com o objetivo de avaliar quimicamente a qualidade das silagens e a degradação ruminal da matéria seca (MS), fibra detergente neutra (FDN) e proteína bruta (PB) das silagens de milho e girassol. Na avaliação químico-bromatológica das silagens, utilizou-se delineamento estatístico inteiramente ao acaso com nove repetições por tratamento (silagem de milho ou girassol) e, para a degradação in situ, utilizou-se delineamento em parcelas subdivididas, com três repetições. A silagem de girassol apresentou maiores concentrações de proteína bruta (11,6 vs 9,4 por cento), extrato etéreo (10,1 vs 3,2 por cento), fibra detergente ácida (42,7 vs 31,9 por cento)e lignina (9,4 vs 3,7 por cento), e menores teores de MS (22,0 vs 34,6 por cento) que a silagem de milho, respectivamente. Apresentou também maiores teores de nitrogênio amoniacal (10,7 vs 5,8 por cento) e ácido acético (3,0 vs 0,79 por cento) e menores concentrações de ácido lático (3,7 vs 11,3 por cento) que a silagem de milho. As taxas de degradação efetiva da MS, FDN e PB da silagem de girassol foram menores do que as da silagem de milho. A silagem de milho apresentou características mais favoráveis ao processo de ensilagem.