A research project assessing the effectiveness of potassium permanganate (KMnO4) for the treatment of iron (Fe) and manganese (Mn) has been conducted by the University of Central Florida (UCF) on behalf of the United States Navy with regards to the water supply on the island of Guam, located in the Marianas Islands. The study consisted of three basic investigative components: one that examined the use of potassium permanganate for iron and manganese control for Fena Lake, a second that examined the existing unit operations that comprised the Navy's water treatment plant (NWTP), and a third that examined iron and manganese field sampling analytical procedures. In the first and primary component of the research, surface water from Fena Lake located within the Naval Magazine in proximity of Santa Rita, Guam was collected at several different lake depths and initially analyzed for iron and manganese using inductively coupled plasma. Subsequent aliquots of Fena Lake collected at the various water depths were transferred to jars then dosed with varying amounts of potassium permanganate after which iron and manganese content was determined. The jars were covered to simulate actual lake to plant transfer conditions experienced at the Navy's on-island facilities. A portion of the jars was dosed with potassium permanganate prior to metals analysis in order to allow for comparisons of baseline conditions. To represent conventional treatment processes, the water samples were then coagulated with aluminum sulfate prior to filtration to remove the oxidized manganese and iron formed from the addition of the potassium permanganate. Coagulated aliquots were filtered and collected to evaluate residual dissolved iron and manganese content. Based on the results of the jar tests it was determined that manganese was reduced by 95% or greater and that iron was completely removed to below the analytical detection limit (0.001 mg/L). It was determined that the potassium permanganate dose required for oxidation of iron was 0.94 mg/mg iron and for manganese was 1.92 mg/mg manganese. It was also observed that when the jars containing aliquots that turned brown in color after potassium permanganate dosing meant that iron and manganese were present and were being oxidized; however, water samples that turned pink were found to be over-dosed with potassium permanganate. The pink water is an undesired characteristic and could result in customer complaints when distributed to the system. The second component of research focused on NWTP existing conditions. Water samples were collected after each key unit operation within the NWTP and analyzed for iron and manganese. This was to determine if pre-chlorination at Fena Lake was effective at removing iron and manganese that could be present in the source water. Analysis was conducted where pre-chlorination at Fena Lake was practiced as well as when no pretreatment was practiced prior to the NWTP. It was determined that the iron and manganese were not detected downstream of the coagulation unit operation within the NWTP even when pre-chlorination was not practiced. Consequently pre-chlorination of Fena Lake source water was not required for controlling iron and manganese under the conditions experienced in this study. A third study was also implemented to confirm that 0.1-micron filters are appropriate for use in preparing samples for analytical determination of iron and manganese analysis at various points within the NWTP. The filtration step is important to delineate between dissolved and suspended iron and manganese forms. Standard Methods 3120B recommends the use of 0.45-micron filters, although based on literature it has been shown that oxidized manganese particles may be smaller than a 0.45-micron pore size. Unless a coagulant was used, the oxidized manganese may not be fully removed via the 0.45-micron filter. To verify the effectiveness of using a 0.1-micron filter, a jar test was conducted to compare the use of a 0.1-micron filter, a 0.45-micron filter, and a 0.45-micron filter after the sample has been coagulated. It was found that the use of a 0.1-micron filter was superior to the use of 0.45-micron filters even with coagulant addition when directly comparing between dissolved and suspended iron and manganese forms. It is recommended that 0.1-microns be utilized in lieu of historically recommended 0.45-micron filters for sample preparation procedures.

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The influence of solution pH, DOC concentration, the relative molecular weight distribution of DOC, and the source of DOC were investigated for their effects on the removal of complexed Fe(II) by alum coagulation and/or KMn04 and H20 2 oxidation. The differentiation between particulate, colloidal, and soluble iron species was achieved through the use of 0.2 urn filters and 100K ultrafilters. Results from oxidation and ultrafiltration studies indicated incomplete complexation of the Fe(II) by DOC in solution. Following the addition of either oxidant, uncomplexed Fe(II) was oxidized to Fe (III) which was either complexed by high molecular weight DOC or formed colloidal iron oxides, both of which were efficiently removed by alum coagulation. Alum coagulation alone, however, was ineffective for removing Fe(II) in the presence of DOC. Results revealed the formation of particulate iron species to be a function of DOC source. The formation of colloidal iron was dependent upon DOC concentration and DOC source. The adsorption of DOC by iron oxides was observed to accompany the formation of colloidal iron species. / Master of Science

Esta pesquisa abordou a influência do ozônio, ácido peracético e permanganato de potássio na inativação dos microrganismos indicadores E.coli, colifago, C.perfringens e Ascaris lumbricoides de efluentes secundários, visando reúso em agricultura. Os efluentes utilizados para os ensaios com ozônio foram provenientes da Estação de Tratamento de Esgoto da cidade de Lins-SP (o tratamento consiste em lagoa anaeróbia seguida de facultativa) e da Estação de Tratamento de Esgoto da cidade de Araraquara-SP, na qual o tratamento é constituído de lagoa aerada seguida de lagoa de sedimentação. Para os ensaios de desinfecção com ácido peracético e permanganato de potássio utilizou-se apenas o efluente da Estação de Tratamento de Esgoto da cidade de Araraquara-SP. Os ensaios de desinfecção demonstraram que o ácido peracético tem maior poder bactericida em relação ao ozônio e permanganato de potássio. O ozônio foi mais eficiente na inativação do microrganismo colifago. Para todos os desinfetantes usados, a concentração da bactéria esporulada C.perfringens permaneceu entre 103 a 104 NMP/100 mL. Todos os desinfetantes, nas concentrações e tempos de contatos testados, mostraram-se tóxicos nas primeiras 24 h ao microcrustáceo Daphnia similis. O desinfetante que alcançou, com menor concentração e tempo de contato, o padrão proposto pela OMS (1989) para irrigação irrestrita foi o ácido peracético com 5 mg/L e tempo de contato de 10 minutos. Já a concentração de ozônio consumida de 40 mg/L e tempo de contato de 10 minutos foram suficientes para atender ao padrão proposto para irrigação restrita. / This research deals with the influence of ozone, peracetic acid and potassium permanganate on the inactivation of indicator microorganisms E.coli, coliphage, Clostridium perfringens and Ascaris lumbricoides secondary effluents, aiming agricultural reuse. The effluents used for the analyses with ozone had been proceeding from the Lins-SP Wastewater Treatment Plant (the treatment consists of an anaerobic lagoon followed by a facultative one) and from the Araraquara-SP Wastewater Treatment Plant, where the treatment consists of an aerated lagoon followed by a sedimentation pond. For the disinfection analyses with peracetic acid and potassium permanganate only the effluent from the Araraquara-SP Wastewater Treatment Plant was used. The disinfection analyses demonstrated that the peracetic acid has greater bactericide power than ozone and potassium permanganate. Ozone was more efficient in the coliphage microorganism inactivation. For all used disinfectants the concentration of sporulated bacteria Clostridium perfringens remained between 103 and 104 NPM/100 mL. All the disinfectants, under the concentration and contact time tested, showed themselves toxic during the first 24 h, and did not show any mortality to the Daphnia similis microorganism after that period. The disinfectant that reached, under lower concentration and contact time, the proposed standard for unrestricted irrigation from WHO (1989) was the peracetic acid with 5 mg/L and contact time of 10 minutes.

Groundwater at many existing and former industrial sites and disposal areas is contaminated by halogenated organic compounds that were released into the environment. The chlorinated solvent trichloroethylene (TCE) is one of the most ubiquitous of these compounds. In situ chemical oxidation (ISCO) has been successfully used for the removal of TCE. The objective of this study was to apply the ISCO technology to remediate TCE-contaminated groundwater. In this study, potassium permanganate (KMnO4) was used as the oxidant during the ISCO process. The study consisted bench-scale and pilot-scale experiments. In the laboratory experiments, the major controlling factors included oxidant concentrations, effects of soil oxidant demand (SOD) on oxidation efficiency, and addition of dibasic sodium phosphate on the inhibition of production of manganese dioxide (MnO2). Results show that higher molar ratios of KMnO4 to TCE corresponded with higher TCE oxidation rate under the same initial TCE concentration condition. Moreover, higher TCE concentration corresponded with higher TCE oxidation rate under the same molar ratios of KMnO4 to TCE condition. Results reveal that KMnO4 is a more stable and dispersive oxidant, which is able to disperse into the soil materials and react with organic contaminants effectively. Significant amount of MnO2 production can be effectively inhibited with the addition of Na2HPO4. Results show that the increase in the first-order decay rate was observed when the oxidant concentration was increased, and the half-life was approximately 24.3 to 251 min. However, the opposite situation was observed when the second-order decay rate was used to describe the reaction. Results from the column experiment show that the breakthrough volumes were approximately 50.4 to 5.06 pore volume (PV). Injection of KMnO4 would cause the decrease in TCE concentration through oxidation. Results also indicate that the addition of Na2HPO4 would not inhibit the TCE removal rate. In the second part of this study, a TCE-contaminated site was selected for the conduction of pilot-scale study. A total of eight remediation wells were installed for this pilot-scale study. The initial TCE concentrations of the eight wells were as follows: C1 = 0.59 mg/L, C1-E = 0.64 mg/L, C1-W = 0.61 mg/L, EW-1 = 0.65 mg/L, EW-1E = 0.62 mg/L, EW-1W = 0.57 mg/L, C2 = 0.62 mg/L, C3 = 0.35 mg/L. C1, EW-1, C2, and C3 were located along the groundwater flow direction from the upgradient (C1) to the downgradient location (C3), and the distance between each well was 3 m. C1-E and C1-W were located in lateral to C1 with a distance of 3 m to C1. EW-1E and EW-1W were in lateral to EW-1 with a distance of 3 m to EW-1. In the first test, 2,700 L of KMnO4 solution was injected into each of the three injection wells (C1, C1-E, and C1-W) with concentration of 5,000 mg/L. Three injections were performed with an interval of 6 hr between each injection. After injection, the TCE concentrations in those three wells dropped down to below detection limit (<0.0025 mg/L). However, no significant variations in TCE concentrations were observed in other wells. In the second test, 2,700 L of KMnO4 solution was injected into injection well (EW-1) with concentration of 5,000 mg/L. Six injections were performed with an interval of 6 hr between each injection. After injection, the TCE concentrations in the injection well dropped down to below detection limit (<0.0025 mg/L). TCE concentrations in (C1, C1-E, C1-W, EW-1E, EW-1W, C2, and C3) dropped to 0.35-0.49 mg/L. After injection, no significant temperature and pH variation was observed. However, increase in conductivity and oxidation-reduction potential (ORP) was observed. This indicates that the KMnO4 oxidation process is a potential method for TCE-contaminate site remediation. The groundwater conductivity increased from 500 £gS/cm to 1,000 £gS/cm, and ORP increased from 200 to 600 mv. Increase in KMnO4, MnO2, and total Mn was also observed in wells. Results from the slug tests show that the hydraulic conductivity remained in the range from 10-4 to 10-5 m/sec before and after the KMnO4 injection.

Made available in DSpace on 2014-06-11T19:30:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-29Bitstream added on 2014-06-13T20:21:11Z : No. of bitstreams: 1 franca_jg_dr_jabo.pdf: 2251025 bytes, checksum: 4391181f6db61217e2ad4bea2e7f55fd (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O objetivo deste estudo foi avaliar o potencial tóxico do permanganato de potássio (KMnO4) através da avaliação da toxicidade aguda (CL50;96 h) e crônica para a tilápia, Oreochromis niloticus e a ecotoxicidade desse composto através de ensaios com o microcrustáceo Ceriodaphnia dubia e com a microalga Pseudokirchneriella subcapitata. Para o teste de toxicidade aguda foram utilizados alevinos de tilápia (0,52 + 0,10g e 3,35 + 0,36 cm), expostos a seguintes concentrações: 0; 0,5; 1,0; 2,0; 4,0 e 6,0 mg.L-1 KMnO4. Os efeitos subletais do KMnO4 foram avaliados pelo do teste de toxicidade crônica, com um grupo controle e duas concentraçõesteste, utilizadas na aqüicultura para o manejo e controle de doenças (1,0 e 4,0 mg.L-1 KMnO4). Para este teste foram utilizadas tilápias (40 g) jovens, expostas por 30 dias, com amostragem de 10 indivíduos por tratamento, nos intervalos de 0, 7, 15 e 30 dias. Os biomarcadores avaliados no presente estudo foram: análises hematológicas, da atividade fagocítica, determinações da concentração de GSH, da atividade enzimática da GST, catalase e peroxidação lipídica e genótoxicas. No teste de toxicidade aguda, o baixo valor de CL50;96h (1,81 mg.L-1), sugere que esta espécie de peixe, nesta fase de desenvolvimento, apresenta grande sensibilidade ao composto. No teste de toxicidade crônica, os peixes expostos na concentração de 1 mg.L-1 de KMnO4 não apresentaram variações significativas nos parâmetros sanguíneos analisados quando comparados ao grupo controle. Na concentração de 4 mg.L-1, as alterações no quadro hematológico indicaram processo de hemólise e redução da atividade fagocítica em consequência da ação oxidante do KMnO4. Nas concentrações de 1 e 4 mg.L-1 KMnO4 houve redução significativa da capacidade fagocítica de macrófagos. Na análise bioquímica, somente a enzima GSH apresentou aumento significativo... / This study aimed know the toxic potential of the potassium permanganate (KMnO4) through the evaluation of the acute (LC50;96h) and cronic toxicity to tilapia, Oreochromis niloticus and the ecotoxicity of this compound through the assays with the microcrustacean Ceriodaphnia dubia and with microalgae Pseudokirchneriella subcapitata. For the acute toxicity test were used tilapia fingerlings (0.52 + 0.10g and 3.35 + 0.36 cm), exposed to concentrations: 0; 0.5; 1.0; 2.0; 4.0 and 6.0 mg.L-1 KMnO4. The sublethal effects of the KMnO4 were evaluated through cronic toxicity test, with a control group and two test concentrations, used in the aquaculture to management and control fishes diseases (1.0 and 4.0 mg.L-1 KMnO4). To this experiment were used with juvenile tilapia (40 g), exposed for 30 days, with samples of 10 individuals from each treatment at intervals of 0, 7, 15 and 30- days. The biomarkers evaluated in this present study were: hematological analysis, phagocytic activity, determination of GSH concentration, of enzymatic activity of GST, catalase, lipid peroxidation and genotoxities. In the acute toxicity test, the low value of LC50;96h (1.81 mg.L- 1), suggests that this species of fish, in this phase of development, it presents the great sensitivity to the KMnO4. In the cronic toxicity test, the fishes exposed in the concentrations of 1 mg.L-1 de KMnO4 did not present significant variations in the analyzed sanguineous parameters when compared with the control group. In concentration of 4 mg.L-1 the hematological alterations indicated process of hemolysis and immunosuppression in consequence of the oxidant action of KMnO4. In the immunologicals analysis, the concentrations of 1 and 4 mg.L-1 KMnO4 had significant reduction of the fagocitic capacity of the fishes suggesting suppression of the immune system. In the analysis biochemical, only the enzyme GSH presented significant increase... (Complete abstract click electronic access below)

Resumo: O objetivo deste estudo foi avaliar o potencial tóxico do permanganato de potássio (KMnO4) através da avaliação da toxicidade aguda (CL50;96 h) e crônica para a tilápia, Oreochromis niloticus e a ecotoxicidade desse composto através de ensaios com o microcrustáceo Ceriodaphnia dubia e com a microalga Pseudokirchneriella subcapitata. Para o teste de toxicidade aguda foram utilizados alevinos de tilápia (0,52 + 0,10g e 3,35 + 0,36 cm), expostos a seguintes concentrações: 0; 0,5; 1,0; 2,0; 4,0 e 6,0 mg.L-1 KMnO4. Os efeitos subletais do KMnO4 foram avaliados pelo do teste de toxicidade crônica, com um grupo controle e duas concentraçõesteste, utilizadas na aqüicultura para o manejo e controle de doenças (1,0 e 4,0 mg.L-1 KMnO4). Para este teste foram utilizadas tilápias (40 g) jovens, expostas por 30 dias, com amostragem de 10 indivíduos por tratamento, nos intervalos de 0, 7, 15 e 30 dias. Os biomarcadores avaliados no presente estudo foram: análises hematológicas, da atividade fagocítica, determinações da concentração de GSH, da atividade enzimática da GST, catalase e peroxidação lipídica e genótoxicas. No teste de toxicidade aguda, o baixo valor de CL50;96h (1,81 mg.L-1), sugere que esta espécie de peixe, nesta fase de desenvolvimento, apresenta grande sensibilidade ao composto. No teste de toxicidade crônica, os peixes expostos na concentração de 1 mg.L-1 de KMnO4 não apresentaram variações significativas nos parâmetros sanguíneos analisados quando comparados ao grupo controle. Na concentração de 4 mg.L-1, as alterações no quadro hematológico indicaram processo de hemólise e redução da atividade fagocítica em consequência da ação oxidante do KMnO4. Nas concentrações de 1 e 4 mg.L-1 KMnO4 houve redução significativa da capacidade fagocítica de macrófagos. Na análise bioquímica, somente a enzima GSH apresentou aumento significativo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study aimed know the toxic potential of the potassium permanganate (KMnO4) through the evaluation of the acute (LC50;96h) and cronic toxicity to tilapia, Oreochromis niloticus and the ecotoxicity of this compound through the assays with the microcrustacean Ceriodaphnia dubia and with microalgae Pseudokirchneriella subcapitata. For the acute toxicity test were used tilapia fingerlings (0.52 + 0.10g and 3.35 + 0.36 cm), exposed to concentrations: 0; 0.5; 1.0; 2.0; 4.0 and 6.0 mg.L-1 KMnO4. The sublethal effects of the KMnO4 were evaluated through cronic toxicity test, with a control group and two test concentrations, used in the aquaculture to management and control fishes diseases (1.0 and 4.0 mg.L-1 KMnO4). To this experiment were used with juvenile tilapia (40 g), exposed for 30 days, with samples of 10 individuals from each treatment at intervals of 0, 7, 15 and 30- days. The biomarkers evaluated in this present study were: hematological analysis, phagocytic activity, determination of GSH concentration, of enzymatic activity of GST, catalase, lipid peroxidation and genotoxities. In the acute toxicity test, the low value of LC50;96h (1.81 mg.L- 1), suggests that this species of fish, in this phase of development, it presents the great sensitivity to the KMnO4. In the cronic toxicity test, the fishes exposed in the concentrations of 1 mg.L-1 de KMnO4 did not present significant variations in the analyzed sanguineous parameters when compared with the control group. In concentration of 4 mg.L-1 the hematological alterations indicated process of hemolysis and immunosuppression in consequence of the oxidant action of KMnO4. In the immunologicals analysis, the concentrations of 1 and 4 mg.L-1 KMnO4 had significant reduction of the fagocitic capacity of the fishes suggesting suppression of the immune system. In the analysis biochemical, only the enzyme GSH presented significant increase... (Complete abstract click electronic access below) / Orientadora: Maria José Tavares Ranzani Paiva / Coorientador: Julio Vicente Lombardi / Banca: Flávio Ruas de Morais / Banca: Carlos Massatoshi Ishikawa / Banca: Claudinei da Cruz / Banca: Cíntia Badaró Pedroso / Doutor

Made available in DSpace on 2015-03-26T13:39:49Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1342175 bytes, checksum: 6e4556bb84bf7f03f6b8c6017712f351 (MD5) Previous issue date: 2012-03-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The maxixe (Cucumis anguria) is a vegetable belonging to the Cucurbitaceae family. The fruits are harvested when still immature, with tender seeds, colored bright green and has a low shelf life. It is a tropical fruit of difficult cultivation in the state of Massachusetts, EUA. This study evaluated the influence of different doses of potassium permanganate, in the form of sachets, during storage in refrigerated conditions at 10 °C on the postharvest quality of fruits of cucumber, simulating the period of transport and marketing from Brazil to the state of Massachusetts, USA. The fruits were sorted, sanitized and packaged in polystyrene trays, containing potassium permanganate sachets at concentrations of 0 (control), 1, 2, 3 and 4 g in 6.5 g the vermiculite. The trays were stored in a chamber at 10 °C. Analyses were performed on days 0, 3, 7 and 10 for the determination of cumulative weight loss (CWL), total chlorophyll content, total soluble sugars (TSS), reducing sugars (RS), non-reducing sugars (ANR) ascorbic acid (vitamin C), starch and visual examination of color and chilling injury. The experimental design was completely randomized, with four replications. Data were analyzed using analysis of variance and regression using the Statistical Analysis System and Genetics of UFV (SAEG-UFV). To compare the treatment means with the control, we used the Dunnett test adopting the 5% level of probability. For the selection of the regression model was based on the significance of the regression coefficients using t-test at 5% probability of the coefficient of determination (R2 = SQReg / SQtrat) and by the biological behavior. Initially there was an increase in chlorophyll content with a subsequent decrease. The increase is due to the exceeded water loss that was higher compared to the degradation rate of the pigment. Treatment with 4 g of KMnO4 retained higher content of chlorophyll pigments and resulted in less drop of vitamin C. Treatment with 4 g KMnO4 provided better appearance, with greener fruits and less darkening of the skin after 3 days of storage. / O maxixe (Cucumis anguria) é uma hortaliça pertencente à família das cucurbitáceas. Os frutos são colhidos ainda imaturos, com sementes tenras, coloração verde-clara e tem baixa vida de prateleira. É um fruto tropical de difícil cultivo no estado de Massachusetts, EUA. O presente trabalho avaliou a influência de diferentes dosagens de permanganato de potássio, na forma de saches, durante o armazenamento, em condição refrigerada a 10°C, na qualidade pós-colheita de frutos de maxixe, simulando o período de transporte e comercialização desta hortícola do Brasil ao estado de Massachusetts, EUA. Os frutos foram selecionados, sanitizados e embalados em bandeja de isopor, contendo saches de permanganato de potássio nas concentrações de 0 (controle), 1, 2, 3 e 4 g, em 6,5 g de vermiculita. As bandejas foram armazenadas em BOD a 10°C. Análises foram realizadas nos dias 0, 3, 7 e 10 para a determinação de perda de massa fresca acumulada (PMF), teor de clorofila total, açúcares solúveis totais (AST), açúcares redutores (AR), açúcares não redutores (ANR), ácido ascórbico (VIT C), amido e análise visual de cor e injúria por frio. O delineamento experimental foi inteiramente casualizado, composto de quatro repetições. Os dados foram analisados por meio de análise de variância e regressão, utilizando-se o Sistema de Análises Estatísticas e Genética da UFV (SAEG-UFV). Para comparar as médias dos tratamentos com o controle utilizou-se o teste de Dunnett adotando-se o nível de 5% de probabilidade. Para a escolha do modelo de regressão baseou-se na significância dos coeficientes de regressão utilizando-se o teste t ao nível de 5% de probabilidade, no coeficiente de determinação (R2 = SQReg / SQtrat) e no comportamento biológico. Inicialmente ocorreu aumento nos teores de clorofila com posterior decréscimo. O aumento é decorrente da perda de água que no início superou a taxa de degradação do pigmento. O tratamento com 4 g de KMnO4 conservou maior conteúdo de pigmentos clorofílicos e resultou em menor queda de vitamina C. O tratamento com 4 g de KMnO4 proporcionou melhor aparência, com frutos verdes e menor escurecimento da casca após 3 dias de armazenamento.

Made available in DSpace on 2015-03-26T13:39:54Z (GMT). No. of bitstreams: 1 texto completo.pdf: 518774 bytes, checksum: 06773571b81e5a7f0d521a081f2219a8 (MD5) Previous issue date: 2006-07-24 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / The objective of this work was to determine the most efficient potassium permanganate (KMnO4) dose associated with plastic packaging in delaying processes related to ripening of 'Sunrise Golden' papaya stored under refrigeration and room temperature. Fruits were wrapped in low-density polyethylene bags with KMnO4 sachets. Two experiments were conducted: Experiment 1: storage at 10.42 ± 0.96 C and 90 ± 5% RH, and KMnO4 doses of 0; 0.5; 1; 1.5; and 2 g/bag; and Experiment 2: storage at 20.05 ± 0.50 C and 90 ± 5% RH and KMnO4 doses of 0; 1; 2; 3; and 4 g/bag. In the Experiment 1, three fruits with average weight of 289±18.49 g each were maintained in the bags for 25 days, while in the Experiment 2, three fruits with average weight of 278±18.86 g each were kept for 15 days at the temperatures previously mentioned. After these periods, the fruits were removed from the bags. Fruits from Experiment 1 were kept at 21.02 ± 0.80 C and 90 ± 5% RH, while fruits from Experiment 2 were kept in the same environment. The experiments were arranged in split plots, with KMnO4 doses in the plots, and in the subplots, the days of evaluation after the removal from packaging, with 0, 1, 2, 3, 5 and 6 days in experiment 1 and 0, 1, 2, 3, 4 and 5 days in experiment 2, in a randomized complete block design with three repetitions and three fruits per experimental unit. For the analyses of CO2 concentration within the bags, experiments with the five KMnO4 doses and five repetitions, with three fruits per experimental unit, were set up in parallel. After 25 days of storage at 10.42 ± 0.96 C, the fruits without KMnO4 were not significantly different from the treated fruits for the characteristics peel color index, consistency of pulp and electrolyte, indicating that refrigeration associated with plastic film was efficient in inhibiting alterations in these characteristics. However, after removing the fruits from conditions of refrigerated storage and modified atmosphere, it was observed the effect of KMnO4 on delaying alterations in pulp firmness, peel color, solute leakage and soluble solids concentration compared to KMnO4 non-treated fruits. After 15 days of storage at 20.05 ± 0.50 C, fruits without KMnO4 had higher CO2 production, more intense peel color, higher cell electrolyte leakage and lower firmness when compared to KMnO4-treated fruits, indicating that non-treated fruits had premature ripening. After removing the packaging, the KMnO4-treated fruits maintained firmness for two days, reaching values similar to the non-treaded ones only on the fifth day of evaluation. / O objetivo deste trabalho foi determinar a dose de permanganato de potássio (KMnO4) associado à embalagem plástica, mais eficiente em retardar os processos relacionados ao amadurecimento do mamão Sunrise Golden armazenado sob refrigeração e à temperatura ambiente. Os frutos foram embalados em filmes de polietileno de baixa densidade, nos quais foram incluídos sachês KMnO4. Foram conduzidos dois experimentos: experimento 1: armazenamento a 10,42 ± 0,96 °C e 90 ± 5% de UR e doses de KMnO4 de 0,0; 0,5; 1,0; 1,5; e 2,0 g/embalagem; e experimento 2: armazenamento a 20,05 ± 0,50 °C e 90 ± 5% de UR e doses de KMnO4 de 0,0; 1,0; 2,0; 3,0; e 4,0 g/embalagem. No experimento 1, três com massa média de 289±18,49 g cada foram mantidos nas embalagens durante 25 dias, enquanto no experimento 2 foram acondicionados três com massa média de 278±18,86 g cada, durante 15 dias, nas temperaturas mencionadas anteriormente. Após esses períodos, os frutos foram retirados das embalagens. Já os do experimento 1 foram mantidos a 21,02 ± 0,80 °C e 90 ± 5% de UR, enquanto os do experimento 2 permaneceram no mesmo ambiente. Os experimentos foram montados em parcelas subdividas, tendo nas parcelas as doses de KMnO4 e, nas subparcelas, os dias de avaliação após a remoção das embalagens, sendo 0, 1, 2, 3, 5 e 6 dias no experimento 1 e 0, 1, 2, 3, 4 e 5 dias no experimento 2, no delineamento inteiramente casualizado com três repetições e três frutos por unidade experimental. Para as análises de concentração de CO2 no interior das embalagens foram montados experimentos à parte com as cinco doses de KMnO4 e cinco repetições, sendo três frutos por unidade experimental. Após 25 dias de armazenamento a 10,42 ± 0,96 °C, os frutos sem KMnO4 não apresentaram diferenças significativas quando comparados com os frutos tratados para as características índice de cor da casca, consistência da polpa e extravasamento de eletrólitos, indicando que a refrigeração associada ao filme plástico foi eficiente em inibir alterações nessas características. No entanto, após a retirada dos frutos das condições de armazenamento refrigerado e atmosfera modificada observou-se o efeito do KMnO4 em retardar alterações na firmeza da polpa, na coloração da casca, no extravasamento de solutos e no teor de sólidos solúveis, em comparação com os frutos não-tratados com KMnO4. Após 15 dias de armazenamento a 20,05 ± 0,50 °C, os frutos sem KMnO4 apresentavam maior produção de CO2, coloração da casca mais avançada, maior perda de eletrólitos celulares e menor firmeza quando comparados com frutos tratados com KMnO4, indicando que os não-tratados tiveram amadurecimento antecipado. Após a retirada das embalagens, os frutos tratados com KMnO4 permaneceram firmes durante dois dias, alcançando valores de firmeza semelhantes aos dos não-tratados somente no quinto dia de avaliação.

Esta pesquisa abordou a influência do ozônio, ácido peracético e permanganato de potássio na inativação dos microrganismos indicadores E.coli, colifago, C.perfringens e Ascaris lumbricoides de efluentes secundários, visando reúso em agricultura. Os efluentes utilizados para os ensaios com ozônio foram provenientes da Estação de Tratamento de Esgoto da cidade de Lins-SP (o tratamento consiste em lagoa anaeróbia seguida de facultativa) e da Estação de Tratamento de Esgoto da cidade de Araraquara-SP, na qual o tratamento é constituído de lagoa aerada seguida de lagoa de sedimentação. Para os ensaios de desinfecção com ácido peracético e permanganato de potássio utilizou-se apenas o efluente da Estação de Tratamento de Esgoto da cidade de Araraquara-SP. Os ensaios de desinfecção demonstraram que o ácido peracético tem maior poder bactericida em relação ao ozônio e permanganato de potássio. O ozônio foi mais eficiente na inativação do microrganismo colifago. Para todos os desinfetantes usados, a concentração da bactéria esporulada C.perfringens permaneceu entre 103 a 104 NMP/100 mL. Todos os desinfetantes, nas concentrações e tempos de contatos testados, mostraram-se tóxicos nas primeiras 24 h ao microcrustáceo Daphnia similis. O desinfetante que alcançou, com menor concentração e tempo de contato, o padrão proposto pela OMS (1989) para irrigação irrestrita foi o ácido peracético com 5 mg/L e tempo de contato de 10 minutos. Já a concentração de ozônio consumida de 40 mg/L e tempo de contato de 10 minutos foram suficientes para atender ao padrão proposto para irrigação restrita. / This research deals with the influence of ozone, peracetic acid and potassium permanganate on the inactivation of indicator microorganisms E.coli, coliphage, Clostridium perfringens and Ascaris lumbricoides secondary effluents, aiming agricultural reuse. The effluents used for the analyses with ozone had been proceeding from the Lins-SP Wastewater Treatment Plant (the treatment consists of an anaerobic lagoon followed by a facultative one) and from the Araraquara-SP Wastewater Treatment Plant, where the treatment consists of an aerated lagoon followed by a sedimentation pond. For the disinfection analyses with peracetic acid and potassium permanganate only the effluent from the Araraquara-SP Wastewater Treatment Plant was used. The disinfection analyses demonstrated that the peracetic acid has greater bactericide power than ozone and potassium permanganate. Ozone was more efficient in the coliphage microorganism inactivation. For all used disinfectants the concentration of sporulated bacteria Clostridium perfringens remained between 103 and 104 NPM/100 mL. All the disinfectants, under the concentration and contact time tested, showed themselves toxic during the first 24 h, and did not show any mortality to the Daphnia similis microorganism after that period. The disinfectant that reached, under lower concentration and contact time, the proposed standard for unrestricted irrigation from WHO (1989) was the peracetic acid with 5 mg/L and contact time of 10 minutes.