Antifungal activity of poly(lactic acid) nanofibers containing the essential oil from Corymbia citriodora Hook or the monoterpenes ß-citronellol and citronellal against mycotoxigenic fungi.

Food contamination by mycotoxigenic fungi is one of the principal factors that cause food loss and economic losses in the food industry. The objective of this work was to incorporate the essential oil from Corymbia citriodora Hook and its constituents citronellal and ß-citronellol into poly(lactic acid) nanofibers; to characterize the nanofibers by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy and differential scanning calorimetry; to evaluate the antifungal activity by the fumigation method; to evaluate the antimycotoxigenic activity against Aspergillus carbonarius, Aspergillus ochraceus, Aspergillus westerdijkiae, Aspergillus flavus, and Aspergillus parasiticus; and to evaluate the morphology of these microorganisms. All the nanofibers had a regular, smooth, and continuous morphology. FTIR analyses confirmed that the active ingredients were incorporated into the polymer matrix. All samples exhibited antifungal and ochratoxigenic inhibitory activities of up to 100% and 99%, respectively, with the best results observed for (PLA + 30 wt% ß-citronellol) nanofibers and (PLA + 30 wt% citronellal) nanofibers. However, 100% inhibition of the production of aflatoxin B1 and B2 was not observed. The images obtained by SEM indicated that the nanofibers caused damage to the hyphae, caused a decrease in the production of spores, and caused deformation, rupture, and non-formation of the conid head, might be an alternative for the control of mycotoxigenic fungi.

Environmentally Friendly New Catalyst Using Waste Alkaline Solution from Aluminum Production for the Synthesis of Biodiesel in Aqueous Medium.

Red mud (RM) is composed of a waste alkaline solution (pH = 13.3) obtained from the production of alumina. It contains high concentrations of hematite (Fe2O3), goethite (FeOOH), gibbsite [Al(OH)3], a boehmite (AlOOH), anatase (Tetragonal-TiO2), rutile (Ditetragonal dipyramidal-TiO2), hydrogarnets [Ca3Al2(SiO4)3-x(OH)4x], quartz (SiO2), and perovskite (CaTiO3). It was shown to be an excellent catalytic mixture for biodiesel production. To demonstrate the value of RM, an environmentally friendly process of transesterification in aqueous medium using waste cooking oil (WCO), MeOH, and waste alkaline solution (WAS) obtained from aluminum production was proposed. Triglycerides of WCO reacted with MeOH at 60 °C to yield mixtures of fatty acid methyl esters (FAMEs) in the presence of 0.019% (w/w) WAS/WCO using the WAS (0.204 mol L-1, predetermined by potentiometric titration) from aluminum production by the Bayer process. The use of the new catalyst (WAS) resulted in a high yield of the products (greater than 99% yield).

Correlation of the presence of acrolein with higher alcohols, glycerol, and acidity in cachaças.

Acrolein is a toxic aldehyde that can be present in various beverages, such as cachaça and other distilled spirits from sugarcane. The objective of this work was to detect and quantify acrolein in samples of cachaça produced by different processes in all regions of Brazil and to evaluate the possible routes of formation of this contaminant from the correlation with other secondary compounds present in the beverage using principal component analysis. Approximately 27.0% of the samples analyzed were outside the limit established by Brazilian legislation for this contaminant, with an average acrolein concentration of 14.01 mg 100 mL-1 anhydrous alcohol (aa). In the other samples, the average concentration was 0.97 mg 100 mL-1 aa. After selecting the variables that most closely correlated with the presence of acrolein in beverages, a positive correlation was found with the presence of butan-2-ol, propan-1-ol and volatile acids, and a slight correlation with the presence of phenolic compounds. Therefore, the presence of acrolein in cachaça can be associated with contamination of the fermentation must by bacteria of the genus Lactobacillus, as a result of the chemical degradation and enzymatic conversion of the glycerol produced during fermentation.

Tandem Transesterification-Esterification Reactions Using a Hydrophilic Sulfonated Silica Catalyst for the Synthesis of Wintergreen Oil from Acetylsalicylic Acid Promoted by Microwave Irradiation.

SiO2-SO3H, with a surface area of 115 m2/g and pore volume of 0.38 cm3g-1, and 1.32 mmol H+/g was used as a 20% w/w catalyst for the preparation of methyl salicylate (wintergreen oil or MS) from acetylsalicylic acid (ASA). A 94% conversion was achieved in a microwave reactor over 40 min at 120 °C in MeOH. The resulting crude product was purified by flash chromatography. The catalyst could be reused three times.

Antifungal and physicochemical properties of Ocimum essential oil loaded in poly(lactic acid) nanofibers.

Poly(lactic acid) (PLA) nanofibres containing different proportions of the essential oils from Ocimum basilicum L. and Ocimum gratissimum L. were prepared by solution blow spinning method. The essential oils were extracted by hydrodistillation and characterized by gas chromatography. MEV, contact angle, DSC and FTIR were used to characterize the nanofibres. The effect of bioative nanofibres on the growth of the fungus and on the production of ochratoxin A were evaluated using the fumigation test. Linalool, 1·8-cineole and camphor were the principal components of the essential oil from O. basilicum, and eugenol was the principal constituent in the oil from O. gratissimum. An increase in the average diameter of the nanofibres was observed with the addition of the essential oils. The essential oils acted as a plasticizer, resulting in a reduction in the crystallinity of the PLA. The encapsulation of essential oils in PLA nanofibres was verified by FTIR. An effective antifungal and antimicotoxygenic activity against Aspergillus ochraceus and Aspergillus westerdjikiae was observed for the bioative nanofibres. These results confirm the potential of PLA nanofibres containing the essential oils for the control of toxigenic fungi that cause the deterioration of food and are harmful to human health.

Determination of the biodegradability of chitosan utilizing the most probable number technique

The present work aimed to evaluate the degradability of the chitosan polymer by soil microorganisms.This evaluation was accomplished using the Most Probable Number (MPN) method by plating in drops so that soil microorganisms capable of degrading the polymeric material could be quantified. Soil samples diluted in three specific culture media for each typeof microorganism were plated –bacteria, fungi and actinobacteria–and they were maintained at 28°C for seven days to determine the growth rate of fungi and actinobacteria, and for 48hoursfor the development of bacteria. Significant differences in the MPN of actinobacteriarelative to the other groups analyzed were observed. Thus, the method used was effective for determining the degradability of the chitosan biopolymer when observing the development of microorganisms subjected to the replacement of thecarbonsource by the addition of 2% w v-1of the chitosan biopolymer to the culture medium. The formation of clear regions around the microbial colonies was a strong indicator of biodegradation.

Characterization, antioxidant potential and cytotoxic study of mangaba fruits / Caracterização, potencial antioxidante e estudo citotóxico de frutos de mangaba

The mangaba (Hancornia speciosa) stands out and has a great potential for economic exploitation and researches have suggested relevant results regarding the nutritional and functional value of this food. Therefore, the objective of this study was to chemically and physicochemically characterize the mangaba fruit harvested in the Middle Araguaia region. It was evaluated the chemical composition, antioxidant activity, volatile compounds, preliminary photochemical studies of phenolic components and the cytotoxic potential of ethanolic extract fruits against Artemia salina. The mean pH, the total titratable acidity and the value for reducing sugars conclude that the mangaba possesses the characteristics appropriate for both fresh consumption and for processing. Between the mean values measured, the fruits presented high fiber content and a low caloric value. The analysis of the antioxidant potential revealed a significant activity and in the volatile compounds analysis, esters were the major class presents. The result of the phytochemical screening revealed that phenols, flavonoids and tannins were present in the ethanolic extract of mangaba and a significant activity in the cytotoxicity assay was observed.

A mangaba (Hancornia speciosa) destaca-se pelo ótimo potencial de exploração econômica e pesquisas têm sugerido resultados relevantes em relação ao valor nutricional e funcional deste alimento. Portanto, o objetivo deste estudo foi caracterizar química e físico-quimicamente os frutos de mangaba colhidos na região do Médio Araguaia. Foi avaliada a composição química, atividade antioxidante, compostos voláteis, estudo fitoquímico preliminar de compostos fenólicos e o potencial citotóxico de extratos etanólicos do frutos contra Artemia salina. O pH, a acidez total titulável e o valor de açúcares redutores concluem que a mangaba possui características apropriadas tanto para consumo in natura quanto para processamento. Entre os valores médios obtidos, os frutos apresentaram alto teor de fibra e um baixo valor calórico. A análise de potencial antioxidante revelou uma atividade significativa e, na análise de compostos voláteis, ésteres representaram a classe predominante. O resultado do ensaio fitoquímico revelou que fenois, flavonoides e taninos estavam presentes no extrato etanólico de mangaba e uma atividade significativa no ensaio citotóxico foi observada.

Determination of ethyl carbamate in cachaça produced from copper stills by HPLC.

Ethyl carbamate (EC) is a common substance in fermented foods and drinks, and its quantification is important because of its carcinogenic nature and its usually presence in alcoholic beverages. The present work involved the development and validation of an analytical method for the evaluation of EC in cachaça by HPLC-FLD after previous derivatization with xanthydrol. The method presented a mean recovery of 94.88%, an intra-day precision of 4.19% (30.0 µgL(-1)) and 3.32% (75.0 µgL(-1)), a coefficient of determination (r(2)) equal to 0.9985, and limits of detection and quantification equal to 6.39 and 21.32 µgL(-1), respectively. The results show that the analytical method is accurate, reproducible and linear over the concentration range from 5.0 to 160 µg of EC per litre. The method was applied to the analysis of EC in cachaça, the analyses being rapid and efficient.

Composition of the essential oil from the leaves of tree domestic varieties and one wild variety of the guava plant (Psidium guajava L., Myrtaceae) / Avaliação dos constituintes dos óleos essenciais de folhas de goiabeira (Psidium guajava L., Myrtaceae) de três cultivares e da planta silvestre

The compositions of the essential oils from the leaves of three domestic varieties of the guava tree Psidium guajava L. (Paluma, Século XXI and Pedro Sato) and of one wild variety were compared. Essential oils were extracted by steam distillation, the components were identified by gas chromatography coupled to mass spectrometry GC-MS, and the apparent concentrations were determined by gas chromatography with a flame ionization detector. The results demonstrated that the three essential oils contained many common substances with a prevalence of 1,8-cineole, whereas the essential oil of the Paluma variety contained 1,8-cineole (42.68 percent) as the major constituent, as well as α-terpineol (38.68 percent). The principal components of the essential oil of the Século XXI variety were 1,8-cineole (18.83 percent), trans-caryophyllene (12.08 percent), and selin-11-en-4-αol (20.98 percent), while those of the Pedro Sato variety and of the wild plant were 1,8-cineole (17.68 percent) and (12.83 percent), caryophyllene oxide (9.34 percent) and (9.09 percent), and selin-11-en-4-α-ol (21.46 percent) and (22.19 percent), respectively.

Os óleos essenciais de folhas de goiabeira Psidium guajava L. de três diferentes cultivares (Paluma, Século XXI e Pedro Sato) e da planta silvestre foram analisados a fim de comparar os seus constituintes. O óleo essencial foi obtido por hidrodestilação em aparelho de Clevenger modificado. Para a caracterização e quantificação dos compostos presentes por CG-EM e CG respectivamente. Os resultados mostraram que os três óleos essenciais analisados apresentam inúmeras substâncias em comum com a predominância do 1,8-cineol. O óleo essencial da cultivar Paluma se difere dos demais devido a alta concentração de 1,8-cineol (42,68 por cento) e do α-terpineol (38,68 por cento). No óleo essencial da cultivar Século XXI observase a presença do 1,8 cineol (18,83 por cento), trans-carifileno (12,08 por cento) e o selin-11-en-4-α-ol (20,98 por cento) como majoritários, enquanto que a cultivar Pedro Sato e a planta silvestre apresentaram com o 1,8 cineol com (17,68 por cento) e (12,83 por cento), oxido de cariofileno (9,34 por cento) e (9,09 por cento) e o selin-11-en-4-α-ol com (21,46 por cento) e (22,19 por cento), respectivamente.

A new series of schistosomicide drugs, the alkylaminoalkanethiosulfuric acids, partially inhibit the activity of Schistosoma mansoni ATP diphosphohydrolase.

The effects of the alkylaminoalkanethiosulfuric acids (AAATs), new schistosomicidal drugs, on Schistosoma mansoni ATP diphosphohydrolase isoforms, members of the NTPDase family, were analyzed. Pre-incubation of worm adult tegument with AAATs derivatives, with small apolar alkyl groups and an apolar alkane portion of 6 or 8 carbon atoms linked to the amino group, inhibited ATPase activity with a Ki 100-1000 microM. Little inhibition (20%) was observed when ADP was the substrate. The 2-[(tert-butyl)amino]-1-ethanethiosulfuric acid (100 microM) which has a less lipophilic structure, inhibited 28% ATPase and 12% ADPase activities, suggesting that the lipophilicity, although important, is not the only requisite for enzyme activity inhibition. The N-(sec-butyl)-2-bromo-1-octanaminium bromide, which contains a bromide atom instead of thiosulphate, inhibited <10% of the enzyme activity, suggesting the involvement of cysteine residue(s) from S. mansoni ATP diphosphohydrolase isoforms in a mixed disulfide formation. Treatment of parasite tegument with 5 mM iodoacetamide or 1 mM dithiothreitol protected ATPase and ADPase activities against inhibition by AAATs, corroborating the participation of disulfide interchange in the AAATs mechanism. Since S. mansoni ATP diphosphohydrolase isoforms and potato apyrase share structural similarities, the latter enzyme was also tested. ADPase activity from potato apyrase was inhibited by 55%, showing a higher sensitivity to 1 mM AAATs than that shown by ADPase activity from the tegument, while the ATPase activities from both samples showed similar inhibition levels. Furthermore, sulfhydryl reagents protected potato apyrase activity. Therefore, it is possible that both soluble S. mansoni ATP diphosphohydrolase and membrane-associated isoforms are targets for the AAATs.

Influence of a protein concentrate used as a fat substitute on the quality of cheese bread

The effects of the use of a protein concentrate as a fat substitute on the quality of cheese bread were investigated. Based on a 10 percent basic fat formulation, the substitution of 10, 25, 50, 75 and 100 percent of the oil in the formula was tested. Physical characteristics were measured, and sensorial parameters were determined. The products with lower levels of fat substitute had higher levels of acceptability. With the increase in the degree of substitution, the cheese bread products were harder, had a thicker crust and presented a less pleasant appearance, less pronounced cheese flavor and a lower degree of acceptance. The use of a fat substitute resulted in a product with a significantly lower fat content and a caloric reduction greater than 25 percent.

O pão de queijo, produto típico do estado de Minas Gerais, Brasil, apresenta elevado valor calórico comparado com outros alimentos, cerca de 300 kcal/100g. Os efeitos da utilização de um concentrado protéico como um substituto de gordura na qualidade do pão de queijo foram investigados. A partir de uma formulação com 10 por cento de óleo foi testada a substituição de 10, 25, 50, 75 e 100 por cento do teor de óleo. As amostras foram avaliadas sensorialmente e suas propriedades físicas foram determinadas. Os pães de queijo com menor substituição da gordura apresentaram maior nível de aceitação. Com o aumento do nível de substituição, os pães de queijo apresentaram pior aparência, tornaram-se mais duros, com maior espessura da crosta, sabor de queijo menos pronunciado e com menor grau de aceitação. O uso do substituto de gordura acarretou um decréscimo substancial no teor lipídico e redução calórica superior a 25 por cento.

Evaluation of the phagocitary capacity of the mononuclear system in an experimental model of obstructive jaundice employing Tc- 99m Escherichia coli

Infections and endotoxemia continue to be the principal causes of morbidity and mortality of patients with obstructions of the bile duct. The objective of the present work was the investigation of the phagocitary capacity of the mononuclear system in an experimental model of obstructive jaundice utilizing Tc-99m E.coli. The levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) were significantly higher in jaundiced rats than in the control animals (p < 0.001). The liver of the jaundiced animals presented a significant reduction in Tc-99m E.coli uptake when compared to the controls (p < 0.001). The data also showed that there was a significant increase in the uptake of Tc-99m E.coli by the lungs of jaundiced rats (p < 0.01). The histological analyses of the liver of jaundiced rats showed an intense and diffuse proliferation of the bile ducts and an intensified polyploidy of the hepatocytes (mean volume = 843 µm³), but no significant alterations were observed in the lungs of either group. This dates could contribute to a better understanding of the mechanisms involved in cases of bacteremia, renal failure and pulmonary dysfunction observed in clinical analyses of obstructive jaundice.

Nos pacientes com obstrução do ducto biliar, as infecções e a endotoxemia continuam sendo uma das principais causas de morbidade e mortalidade. O objetivo desse trabalho foi investigar a capacidade fagocitária do sistema mononuclear, em um modelo experimental de icterícia obstrutiva, utilizando Tc-99m E.coli. Os níveis de aspartato aminotransferase (AST), alanina aminotransferase (ALT) e fosfatase alcalina (PAL) nos ratos com ligadura do ducto biliar comum (CBD) encontram-se significativamente mais elevados do que nos ratos sham. (p < 0.001). O fígado dos animais ictéricos apresentou uma significativa redução na captação da Tc-99m E.coli quando comparado com o controle. Os dados mostraram também, que houve um aumento significativo na captação da Tc-99m E.coli pelo pulmão dos ratos ictéricos (p < 0.01). O exame histológico dos cortes de fígado dos animais ictéricos apresentou proliferação intensa e difusa dos ductos biliares e uma acentuada poliploidia dos hepatócitos (volume médio: 843 µm³), Não foram observadas alterações significativas nos pulmões de nenhum grupo.

Assessment of bacterial translocation in obstructive jaundice using Tc-99m Escherichia coli

In obstructive jaundice, the passage of bacteria and endotoxins through the intestine wall to reach the systemic circulation is associated with septicemia, renal failure and pulmonary dysfunction. The aim of this work was to investigate bacterial translocation utilizing 99mTc-E.coli in an experimental model of obstructive jaundice. The levels of bilirubin in rats that were subjected to ligature of the bile duct were significantly increased when compared to control animals (p < 0.001). The biodistribution results did not show any translocation of 99mTc-E.coli to the mesenteric lymphatic nodules, liver, spleen or lungs of the rats that suffered ligature of the bile duct (p > 0.05). The evaluation of the intestinal permeability using "per os" administration of 99mTc-DTPA showed 1.61 ± 0.57 percent and 1.39 ± 0.72 percent of radioactivity in the urine of the control and jaundice animals, respectively. The histological analysis of the distal wall of the ileum showed that the covering epithelium and the crypt were morphologically preserved in both groups. The seven-day period after the ligature of the bile duct may not have been long enough to promote modifications in intestinal wall to occur so as to permit the passage of Tc-99m E.coli.

Na icterícia obstrutiva, a passagem de bactérias e endotoxinas através da parede intestinal alcançando a circulação sistêmica está associada com septicemia, falência renal e disfunção pulmonar. A proposta deste trabalho foi investigar a translocação bacteriana, empregando a Tc-99m E.coli, em um modelo experimental de icterícia obstrutiva. Os níveis de bilirrubina nos ratos que sofreram a ligadura do ducto biliar estavam significativamente aumentados quando comparados com os valores dos animais controles (p<0,001). Os resultados de biodistribuição não mostraram translocação da Tc-99m E.coli para os nódulos linfáticos mesentéricos, fígado, baço e pulmões dos ratos que sofreram ligadura do ducto biliar (p>0,05). A avaliação da permeabilidade intestinal usando a administração "per os" de 99mTc-DTPA mostrou um percentual de eliminação deste radiofármaco na urina de 1,61±0,57 e 1,39±0,72 para os animais controles e ictéricos, respectivamente. A análise histológica da parede distal do íleo mostrou que tanto o epitélio de revestimento quanto as criptas apresentaram morfologicamente conservados em ambos os grupos. O tempo transcorrido, 7 dias, após a ligadura do ducto biliar talvez não tenha sido longo o suficiente para promover modificações na parede intestinal de modo a permitir a passagem da 99mTc-E.coli.

Technetium-99m ceftizoxime kit preparation

The aim of this work was to prepare a kit of 99mTc-ceftizoxime (99mTc-CFT), with stability and biological activity preserved, able to identify a septic focus (E. coli) in the experimental infection model in rats. The preparation of the CFT kit involved the use of lyophilized solutions containing the antibiotic ceftizoxime and the sodium dithionite reducing agent (6.0 mg/mL). After lyophilization, the kit was reconstituted with 1.0 mL of sodium 99mTc-pertechnetate solution (Na99mTcO4-) with an activity of 370 MBq. The solution was boiled for 10 min and filtered through a cellulose ester filter. The labeling efficiency was on the order of 92 percent, remaining stable for six hours and the kit remained stable for two months. The biological activity of the 99mTc-CFT was evaluated by diffusion in agar impregnated with E.coli and S. aureus. Seven Wistar rats, weighing from 200 to 250 g, were used for the development of the septic focus. After 24 hours from the induction of the infectious site (E.coli), the animals were anesthetized and 0.1 mL of 99mTc-CFT (37 MBq) was injected into the tail veins of the animals. The images were obtained with a gamma camera one, two and six hours after injection and the regions of interest (ROIs) were calculated. The diameters of the inhibition halos for 99mTc-CFT were 27.16 ± 0.23 and 27.17 ± 0.20 for S.aureus and E.coli, respectively, while those for the unlabeled CFT were 30.4 ± 0.33 and 29.43 ± 0.26, respectively. The results for the biodistribution of 99mTc-CFT in infected animals furnished a ratio of 1.97 ± 0.31, 2.10 ± 0.42 and 2.01 ± 0.42 for cpm-target/cpm-no target for the one, two and six-hour periods, respectively. The images showed a clear uptake of labeled antibiotic (99mTc-CFT) by the infectious site during the experiment. The results attest to the viability of producing a kit with 99m technetium-labeled ceftizoxime for the investigation of infectious processes.

O objetivo deste trabalho foi preparar um kit de Tc-99m Ceftizoxima (99mTc-CFT), com estabilidade e atividade biológica preservadas, capaz de identificar um foco séptico (E.coli) em um modelo experimental de infecção em ratos. A preparação do kit de CFT baseou-se em uma mistura de soluções contendo o antibiótico ceftizoxima (2,5mg/mL) e o agente redutor ditionito de sódio (6,0mg/mL) que foram submetidos a um processo de liofilização. Após a liofilização, o kit foi reconstituído with 1,0 mL de solução de pertecnetato de sódio (Na99mTcO4 -), contendo uma atividade de 370 MBq. Em seguida, a solução foi incubada, por 10 min, em banho fervente (1000C) e, posteriormente, foi resfriada em água corrente por 5 min. A eficiência de marcação foi da ordem de 92 por cento permanecendo estável por 6 horas e o kit permaneceu estável por 2 meses. A atividade biológica do 99mTc-CFT foi avaliada por difusão em ágar impregnado com E.coli e S. aureus. Foram utilizados 07 ratos Wistar, pesando entre 200 a 250 g, para o desenvolvimento do foco séptico. Após 24 horas da indução do foco infeccioso (E.coli), os animais foram anestesiados e 0,1 mL da 99mTc-CFT (37 MBq) foi injetado na veia da cauda dos animais. As imagens de 1, 2 e 6 horas após a injeção foram adquiridas em uma gama câmara e as regiões de interesse (ROIS) foram calculadas. Os valores obtidos dos diâmetros dos halos de inibição para 99mTc-CFT foram 27,16±0,23 e 27,17±0,20 para S. aureus e E.coli, respectivamente, sendo que para CFT não marcada foram 30,4±0,33 e 29,43±0,26, respectivamente. Os resultados obtidos da biodistribuição da 99mTc-CFT nos animais com focos infecciosos mostraram uma relação alvo/não alvo de 1,97±0,31, 2,10±0,42 e 2,01±0,42 para os tempos de 1, 2 e 6 horas, respectivamente. As imagens obtidas mostraram nítida captação do antibiótico marcado (99mTc-CFT) pelo foco infeccioso ao longo do experimento. Os resultados obtidos neste...

Verificaçäo do Estado de conservaçäo e da utilizaçäo de sais de propionato em päes de forma / Checking the state of conservation and use of propionic in loaf bread

O ácido propiônico é usado sob a forma de sais de cálcio e sódio como conservador de produtos como chocolate, picles, massas e produtos de confeitaria e panificaçäo, devido à sua propriedade fungicida. Foi feita uma amostragem estatística a partir dos Supermercados e Padaria das 9(nove) regionais de Belo Horizonte: Oeste, Norte, Nordeste, Leste, Venda Nova, Pampulha, Barreiro, Noroeste e Centro Sul. Foram analisadas 191 amostras de päo de forma coletadas pelo Serviço de fiscalizaçäo da Prefeitura Municipal, num total de 24 marcas diferentes. O teor médio encontrado de propionato, expresso em ácido propiônico, foi de 0,13(por cento) com um percentual de reprovaçäo de 12,56(por cento). O método de análise utilizado foi a extraçäo do ácido propiônico com éter e a cromatografia gasosa para a quantificaçäo. Quanto à contagem de bolores e leveduras 12,70(por cento) das 189 amostras analisadas apresentaram resultado acima do limite máximo permitido. A determinaçäo de unidade foi feita em 56 amostras, sendo que 37 66,07(por cento) apresentaram teor acima do permitido pela legislaçäo. As amostras foram analisadas dentro do prazo de validade e foi observada uma variaçäo muito grande deste prazo, até mesmo para uma mesma marca. (AU)

the use of propionic acid as a preservative in products such as chocolate, pickles, pastries and bakery goods is widespread because of its fungicidal properties This acid is nonnally employed in fonn of its salts. A total of 191 samples of loaf bread were analyzed. The samples were collected from supermarkets and bakeries ofthe nine regions of Belo Horizonte. The propionic acid was extracted with ethyl ether in acid médium with quantification by gas chromatography using a flame ionization detector. Concurrently, the moisture and the counting of fungi and yeast was done.The analyses were executed during the period of validity of the products; a large variation in these periods was observed even among products of the same brand and type of bread. The mean propionate contente encountered was 0,13%, expressed as propionic acid. The degree of condemnation was 12,56%, Based on the brazilian legislation. A total of 12,70% of the samples presented Fungi and yeast counts over the maxim um limit. In the samples analyzed For moisture, 66% presented levels above the maximum limit of 35% w/w for whole Wheat or rye bread or 30% w/w for others breads. (AU)

Persistência de deltametrina em espigas de milho armazenadas / Persistence of deltamethrin in stored corn spike

Foram analisadas 78 amostras de espigas de milho, após tratamento com deltametrina e armazenamento em paióis, localizados em algumas regioes de atuaçao da EMATER e no Centro Nacional de Pesquisa de Milho e Sorgo da EMBRAPA, Sete lagoas. A primeira amostragem foi retirada em maio de 1992 e as seguintes bimestralmente até fevereiro de 1993. Cada amostra foi subdividida em amostras de graos, palha e rolao de milho sendo as duas últimas obtidas por moagem. Nao foi detectada a presença de deltametrina nos graoes e os níveis encontrados nas amostras de palha foram em geral acima de 1 mg/Kg, o que indica que nao houve penetraçao do inseticida no interior da espiga. O rolao de milho, que é usado como raçao animal, apresentou resíduos dentro do limite permitido pela legislaçao (1 mg/Kg). Os resultados encontrados mostraram que nao houve degradaçao da deltametrina durante os meses de armazenagem.

Schistosomicidal activity of alkylaminooctanethiosulfuric acids

The schistosomicidal activity of a new series of alkylaminooctanethiosulfuric acids was studied in white Swiss mice infected with the L.E. strain of Schistosoma mansoni (Belo Horizonte, MG, Brazil). In a preliminary screening of six compounds, two derivatives - 2-[(1-methylpropyl)amino]-1-octanethiosulfuric acid and 2-[(1-methylethyl)-amino]-1-octanethiosulfuric acid - given orally in doses of 300 mg/kg/day for five consecutive days, caused interruption of the oviposition and the hepatic shift of more than 90 of the worms. Both compounds caused a significant reduction in worm burden and, interestingly, the female schistosomes were more susceptible. With the therapeutic schedule of two doses of 800 mg/kg over a 20 day interval, the death of almost all the females and about 50 of the males was observed. Female worms recovered from treated mice showed scattered vitteline glands. Results of in vitro experiments against different developmental stages of the parasite revealed the induction of paralysis and damage to the tegument membrane. The drugs presented no toxic effects on the animals.