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One possible alternative to chemotherapeutic agents in the treatment and prevention of diseases in fish farms is the use of Piper aduncum essential oil. However, ecotoxicological data are required to ensure its proper use and to prevent adverse effects on non-target organisms. These data are relevant since this essential oil is described as having insecticidal, molluscicidal and cytotoxic activitiy that may be associated with its chemical composition. Thus, the aim of this study was to evaluate the ecotoxicity of P. aduncum essential oil to five test organisms using the species sensitivity distribution (SSD) statistical approach. The chemical composition of the essential oil was characterized by means of gas chromatography coupled to mass spectrometry (GC-MS) and gas chromatography-flame ionization detection (GC-FID) for identification and quantitation purposes, respectively. The main component (75.5%) of the essential oil was dillapiole. The hazardous concentration for 5% of biological species (HC5) was calculated to determine the 95% protection level, resulting in a value of 0.47 mg L-1 (with a confidence interval of 0.028 - 1.19 mg L-1. ). A concentration range related to the level of protection for aquatic communities (the predicted no-effect concentration, PNEC) was determined through the application of safety factors to the HC5 value. The ecotoxicity parameters showed that P. aduncum essential oil can be used safely in water bodies at a concentration equal to or below 0.09 mg L-1. RESUMO Uma possível alternativa ao uso de fármacos veterinários no tratamento e prevenção de doenças na piscicultura é o uso do óleo essencial de Piper aduncum. No entanto, são necessários dados ecotoxicológicos para garantir seu uso apropriado sem causar efeitos adversos a organismos não alvo. Esta informação é relevante, pois esse óleo essencial é descrito como tendo atividades inseticidas, moluscicidas e citotóxicas, possivelmente associadas à sua composição química. Assim, o objetivo deste estudo foi avaliar a ecotoxicidade do óleo essencial de P. aduncum para cinco organismos-teste, usando o método estatístico da Distribuição da Sensibilidade das Espécies (SSD). A composição química do óleo essencial foi caracterizada por cromatografia gasosa acoplada a espectrometria de massa (GC-MS) e cromatografia gasosa com detector de ionização de chama (GC-FID), para fins de identificação e quantificação, respectivamente. O principal componente (75,5%) do óleo essencial foi o dilapiol. A concentração perigosa para 5% de espécies biológicas (HC5) foi calculada com um nível de proteção de 95%, resultando em um valor de 0,47 mg L-1 (com intervalo de confiança de 50% = 0,028 - 1,19 mg L-1). A faixa de concentração relacionada aos níveis de proteção para comunidades aquáticas (concentração sem efeito previsto - PNEC) foi calculada através da aplicação de fatores de segurança ao valor de HC5. Os parâmetros de ecotoxicidade indicaram que o óleo essencial de P. aduncum pode ser usado com segurança em corpos d’água se a concentração for igual ou inferior a 0,09 mg L-1.

Resumo: O objetivo do trabalho foi avaliar a atividade antimicrobiana in vitro de diferentes óleos essenciais e suas combinações contra linhagens patogênicas de Salmonella typhimurium ATCC 13311 e Staphylococcus aureus ATCC 13565. Foram testados ao todo 41 óleos essenciais e as combinações em pares dos óleos de alecrim-pimenta (Lippia sidoides Cham.), capim-limão (Cymbopogon citratus Stapf.), tomilho (Thymus vulgaris L.), orégano (Origanum vulgare L.) e canela (Cinnamomum cassia (L.) D.Don. para observar efeitos adicionais ou não na inibição dos microrganismos. Os resultados mostraram que as melhores atividades antimicrobianas para os dois microrganismos foram obtidas utilizando os óleos de Thymus vulgaris L. (tomilho), Origanum vulgare L. (orégano) e Lippia sidoides Cham. (alecrim-pimenta). As combinações de cada par dos óleos de alecrim-pimenta, capim-limão, tomilho, orégano e canela não apresentaram uma melhora adicional no efeito para os patógenos estudados quando comparados com os seus óleos testados isoladamente. As composições químicas dos óleos essenciais mais ativos foram obtidas por meio de análises por cromatografia gasosa acoplada à espectrometria de massas (CG-EM), sendo que os compostos majoritários do óleo de orégano foram carvacrol (69,1%) e p-cimeno (18,8%), do óleo essencial de tomilho foram timol (45,5%) e p-cimeno (35,6%) e do alecrim-pimenta foram o timol (77,2%) e p-cimeno (14,2%). Análises quantitativas de p-cimeno, carvacrol e timol nos três óleos foram realizadas e comparadas com as composições químicas mostrando resultados proporcionalmente coerentes, exceto para p-cimeno, que foi quantificado com menores porcentagens por esse método. A aplicabilidade dos óleos selecionados, ou das substâncias presentes isoladas seria diretamente nos alimentos, com a finalidade de inibir ou controlar o crescimento desses patógenos, contribuindo assim para a segurança dos alimentos. ? Abstract: The aim of this study was to evaluate the in vitro antimicrobial activity of several essential oils and their combination against pathogenic strains of Salmonella typhimurium ATCC 13311 and Staphylococcus aureus ATCC 13565. A total of 41 essential oils and the combinations in pairs of the oils of rosemary pepper (Lippia sidoides Cham.), lemongrass (Cymbopogon citratus Stapf.), thyme (Thymus vulgaris L.), origanum (Origanum vulgare L.) and cinnamon (Cinnamomum cassia (L.) D.Don) were tested to observe additional effects or not in the inhibition of microorganisms. The results showed that the best antimicrobial activities for the two microorganisms were obtained using the oils of Thymus vulgaris L. (thyme), Origanum vulgare L. (origanum) and Lippia sidoides Cham. (rosemary pepper). The combinations of each pair of rosemary pepper, lemongrass, thyme, origanum and cinnamon oils did not show any further improvement in the effect for the studied pathogens when compared to their oils tested alone. The compositions of the most active essential oils were obtained by gas chromatography coupled to mass spectrometry (GC-MS). The major compounds in origanum oil were carvacrol (69.1%) and p-cymene (18.8%), thyme essential oil were thymol (45.5%) and p-cymene (35.6%) and rosemary pepper were thymol (77.2%) and p-cymene (14.2%). Quantitative analyses of p-cymene, carvacrol and thymol confirmed the presence in thyme, oregano and pepper rosemary oils and were compared with the chemical composition showing similar results, except for p-cymene, which was quantified with lower percentages in these oils. Made available in DSpace on 2021-12-08T19:01:50Z (GMT). No. of bitstreams: 1 Penteado-Avaliacao-in-vitro-2021.pdf: 983133 bytes, checksum: 78115d004258dd32005df9294e12f8f3 (MD5) Previous issue date: 2021

The huge biological diversity of the Brazilian Cerrado is an important source of economically interesting microbial agents. The phylum Actinobacteria plays an important role in nutrient cycling, potentially improving their availability to plants. In this study, we isolated an actinobacteria (strain 3AS4) from wheat rhizospheres of crops cultivated in the Cerrado biome. Strain 3AS4 was identified as belonging to the genus Streptomyces and had phosphorus mobilization ability, mineralizing approximately 410 mg ml-1 from phytate, 300 mg ml-1 from calcium phosphate, and 200 mg ml-1 from rock phosphate. The analysis of the actinobacteria crude extract by spectrometric techniques revealed the presence of gluconic and 2-ketogluconic acid, and a greenhouse experiment was carried out to evaluate its plant growth promotion activity in soybean. Soil in its natural condition (with no phosphorus addition), 40 kg ha􀀀1 rock phosphate from Bayovar (RP) added to soil, and triple super phosphate (SPT) added to soil were used. Significant differences in plant height were observed at 6 weeks when the plants were inoculated with the 3AS4 strain. The growth of inoculated plants in natural condition was promoted in 17% compared with the RP and SPT non-inoculated conditions, suggesting that inoculation can enable plants to grow with lower chemical P fertilizers. In the plants that were inoculated with the 3AS4 strain in the RP condition, the plant height increased by approximately 80% and the shoot:root ratio was approximately 30% higher compared to control conditions (non-inoculated plants in natural conditions). 3AS4 has P-solubilizing potential and can be exploited as an inoculant for soybean cultivation. These results suggest that this actinobacterium is a valuable resource for sustainable agriculture and will allow the reduction of phosphate fertilization in the future. Made available in DSpace on 2021-08-12T18:00:25Z (GMT). No. of bitstreams: 1 Queiroz-Actinobacterium-strain-2021.pdf: 1861839 bytes, checksum: 1086e2f573058785947282cdc37c76b1 (MD5) Previous issue date: 2021

Shikimic acid (SA) has witnessed a strong increase in recent years due to the increasing demand of the pharmaceutical and cosmetic industry. The SA is used as a precursor for the synthesis of oseltamivir phosphate (Tamiflu®), a potent viral inhibitor and is extracted from the plant Illicium verum Hook which has a limited availability. This article proposed the use of Urochloa plantaginea (Link.) webster and glyphosate, as an alternative source of SA. U. plantaginea plants with 3 - 4 tillers and 4 - 6 leaves were harvest at 3, 6, 9 and 12 days after application (DAT) of low rates of glyphosate. Samples were dried, extracted, analyzed by HPLC and LC-MS/MS. The maximum SA concentrations were observed at 6 days after glyphosate at 36 g.a.e.ha-1 was applied in plants of U. plantaginea with 4 to 6 leaves. The capability of this annual gramineae to produce elevated SA levels throughout the entire biomass affords its potential for a greater yield on a per hectare basis. ? Resumo: O interesse pelo ácido chiquímico (SA) tem apresentado um forte incremento nos últimos anos devido à crescente demanda da indústria farmacêutica e cosmética. O SA é utilizado como um precursor para a síntese do fosfato de oseltamivir (Tamiflu®), um potente inibidor viral. Este ácido é extraído principalmente da planta Illicium verum Hook. A disponibilidade desta planta é um fator limitante para o crescimento do mercado no futuro próximo. Este artigo propõe Urochloa plantaginea (Link.) webster tratada com sub doses de glifosato, como uma fonte alternativa de SA. Plantas de U. plantaginea com 3 - 4 perfilhos e 4 a 6 folhas foram tratadas com subdoses de glifosato e coletadas aos 0, 3, 6, 9 e 12 dias após sua aplicação (DAT). As amostras foram secas, extraídas e analisadas por HPLC e confirmadas por LC-MS/MS. As concentrações máximas de SA foram observadas aos seis dias após aplicação do glifosato a 36 g.e.a.ha-1 em plantas de U. plantaginea com 4 - 6 folhas. A capacidade anual dessa gramínea para produzir níveis elevados de SA em toda a biomassa, pode ser uma fonte economicamente viável de SA. Made available in DSpace on 2020-10-10T09:16:36Z (GMT). No. of bitstreams: 1 Cerdeira-Glyphosate-shikimic-2020.pdf: 923423 bytes, checksum: de786d902560a1b2b683642eaf12ea7b (MD5) Previous issue date: 2020

Resumo: Surtos de doenças bacterianas têm atuado como importante fator limitante para a aquicultura, afetando a sua produção e, como consequência, diminuindo a produtividade. O tratamento dessas doenças é realizado por meio do uso de antibióticos sintéticos. No entanto, esses produtos estão associados ao risco de surgimento de microrganismos resistentes, além de poderem deixar resíduos das substâncias nos peixes, causando riscos potenciais à saúde humana e ao ambiente. Devido a isso, tem surgido a necessidade de realizar pesquisas por alternativas mais saudáveis e sustentáveis. Assim, extratos de plantas e óleos essenciais vêm sendo utilizado como fonte de novas moléculas bioativas. O objetivo desse trabalho foi investigar o potencial antimicrobiano de 31 óleos essenciais, adquiridos comercialmente, utilizando-se cepas referências de Aeromonas hydrophila(ATCC 7966) e de Streptococcus agalactiae(ATCC 13813). Para o bioensaio foi utilizado o método de disco difusão. Os resultados obtidosdemonstraram alto potencial antimicrobiano de dois óleos essenciais para ambas às bactériase as análises realizadas por cromatografia gasosa acoplada à espectrometria de massas detectaram a presença de compostos majoritários sendo: orégano (carvacrol e o-cimeno), tomilho (timol e o-cimeno). ? Abstract: Outbreaks of bacterial diseases is an important limiting factor for aquaculture, affecting its production and, consequently, decreasing productivity. Synthetic antimicrobials are usually used to treat these diseases. However, these products are associated with the risk of emergence of resistant microorganisms, and may leave residues of the substances in fish, causing potential risks to human health and the environment. Consequently, there has been a need to search for healthier and more sustainable alternatives. Thus, plants extracts and essential oils have been used as a source of new bioactive molecules. The objective of this work was to investigate the antimicrobial potential of 31 commercially acquired essential oils using references strains of Aeromonashydrophila (ATCC) 7966 and Streptococcus agalactiae (ATCC 13813). The diffusion disc method was used for the bioassay. The results showed high antimicrobial potential of two essential oils for both bacteria and the analyzes performed by gas chromatographycoupled to-mass spectrometry detected the presence of major compounds: oregano (carvacrol and o-cymene), thyme (thymol and o-cymene). Made available in DSpace on 2019-12-03T00:36:04Z (GMT). No. of bitstreams: 1 PenteadoAtividadeAntimicrobiana2019.pdf: 715362 bytes, checksum: 8a20cc65f4dee27add603618364fd5eb (MD5) Previous issue date: 1

Made available in DSpace on 2021-06-25T10:47:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-12-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Empresa Brasileira de Pesquisa Agropecuária Antibiotics, Hematological Variables, Oxidative stress, Aquaculture; Agricultural Water Management; Environmental Science; Environmental Risk Assessment; Environmental Toxicology; Toxicology Intensive fish cultivation has a high incidence of infection, which is often controlled by administering antibiotics. Florfenicol (FF) is one of the two antimicrobial drugs permitted for aquaculture in Brazil. Due to their intensive use, potentially harmful effects on aquatic organisms are of great concern. In this sense, we investigated whether the presence of FF in cultivation water could change the health parameters of Nile tilapia. For this, we evaluated hemoglobin, hematocrit, mean corpuscular hemoglobin (MCHC) concentration, mean corpuscular volume (MCV), total plasma protein (TPP), number of circulating red blood cells and leukocytes, as lipid peroxidation levels, catalase activity and glutathione S-transferase activity of fish exposed to 11.72 mg L−1 of FF in water for 48 h. The fish were divided into two groups: Nile tilapia in water with FF or without FF (control). Exposure to FF in cultivation water for a short period didn't change the hematological variables analyzed, but caused changes in liver ROS (Reactive oxygen species) markers of the Nile tilapia, which was revealed by lipid peroxidation levels, catalase activity, and glutathione S-transferase. The 48h exposure period was enough to induce oxidative stress in hepatocytes, causing cellular oxidative damage. Therefore, the antibiotic florfenicol may cause toxicity to organisms and aquatic ecosystems, even at a sublethal concentrations near 1/100 LC50-48h for fish species. Institute of Chemistry University of Campinas, POB 6154 Joint Graduate Program in Physiological Sciences Federal University of São Carlos -UFSCar/São Paulo State University UNESP Campus Araraquara Embrapa Environment Brazilian Agricultural Research Corporation (EMBRAPA), Rod. SP 340, Km 127,5, Caixa Postal 69 Joint Graduate Program in Physiological Sciences Federal University of São Carlos -UFSCar/São Paulo State University UNESP Campus Araraquara Empresa Brasileira de Pesquisa Agropecuária: 0117020010606007

Background and Aim: The commercial formulations of the herbicide atrazine (cATZ) are widely employed in Brazilian agriculture, and, as a consequence, ATZ has been found at levels above that established by law in the river basins in Brazil. Although the toxicity of ATZ in fish is well documented, there are few studies on the recovery capacity after cATZ exposure. This work aimed to evaluate, using several biomarkers, the toxic effects of long-term exposure to the sublethal (3.57 mg/L) and nonlethal realistic (3.00 ?g/L) cATZ concentrations followed by a recovery assay, in fingerlings of a Brazilian teleost, the Piaractus mesopotamicus (pacu). Materials and Methods: Pacu fingerlings were housed in glass tanks and divided into the following experimental groups (two tanks/group): Exposure control = EC, recovery control = RC, the sublethal groups exposed to 3.57 mg/L of cATZ, (sublethal exposure group = SLE and sublethal recovery group = SLR) and the nonlethal groups treated with 3.00 μg/L of cATZ (nonlethal exposure group = NLE and nonlethal recovery group = NLR). The exposure assay was semi-static with a duration of 30 days and the recovery assay (after cATZ withdrawal) lasted 14 days. Several biomarkers were evaluated in fingerlings from all groups: The swimming behavior, the body weight gain, the micronucleus formation and nuclear alterations in erythrocytes, and the hepatic and renal histopathology analyzed by qualitative and semi-quantitative morphological methods (using light and electron microscopy). Results: No significant difference in weight gain was observed among the groups after the exposure and recovery assays. The sublethal exposure induced impaired swimming movements, significant histopathological alterations, including necrosis in the liver and kidney, and a significant increase in the frequency of micronuclei in erythrocytes. The nonlethal exposure induced only subtle histopathological changes in the liver and kidney. After recovery assay, no genotoxic alteration was noted in pacu exposed to sublethal concentration, while the cATZ-induced kidney damage was partially reversed but not the hepatic injury. Conclusion: cATZ exhibits long-term toxic effects on pacu, even at relatively low concentrations, affecting mainly the liver and the kidney, and the effects of sublethal concentration are only partially reversed after cATZ withdrawal. Made available in DSpace on 2020-07-29T11:16:03Z (GMT). No. of bitstreams: 1 Queiroz-effects-sublethal-2020.pdf: 3843628 bytes, checksum: 31e9f6793901cac6fbd3e4c5fee98878 (MD5) Previous issue date: 2020

The analysis of volatiles is an alternative in the routine of quality control of fruits, since the volatile metabolites can change in the presence of microorganisms. A well-established method for extracting volatiles is the solid phase microextraction (SPME). This work aims to define some parameters (fiber coating, conditioning time and fiber exposure time) for an effective extraction. Whole papaya was inserted into a hermetically closed glass bottle and the system was left in conditioning for the volatiles accumulation. Then, extraction by SPME and subsequent desorption in a gas chromatograph was performed. Two fibers were evaluated: a 100 μm polydimethylsiloxane (PDMS) and a 65 μm polydimethylsiloxane/divinylbenzene (PDMS/DVB). The PDMS/DVB fiber extracted the highest number of volatiles. Central composite design (CCD) was performed to assess the effect of papaya conditioning time and the fiber exposure time on the response: number of detectable peaks. Both variables studied and their interactions were significant for the response. ANOVA showed that the quadratic terms and the lack of fit were not significant (p

Resumo: Aeromonas hydrophila e Streptococcus agalactiae são bactérias responsáveis pela incidência de doenças severas em peixes, ocasionando perdas significativas na aquicultura. Para tratar essas doenças são utilizados antibióticos, os quais podem deixar resíduos nos alimentos e ocasionar resistência antimicrobiana. Desse modo, o controle de patógenos e a profilaxia de enfermidades deve ser realizado com a finalidade de minimizar os impactos negativos nos organismos aquáticos, nos seres humanos e no meio ambiente. Assim, tem se buscado alternativas mais saudáveis para substituir essas moléculas sintéticas e o uso de bactéria ácido láticas (BALs) e ou seus produtos de metabolismo é uma delas. Neste trabalho, foi avaliada a atividade antagonista de bactérias ácidos láticas bem como o produto do metabolismo destas, cultivada em dois diferentes meios de crescimento, leite em pó à 10% e meio ?De Man Rogosa & Sharpe? (MRS) acrescido de leite (2%) em pó, contra patógenos de peixes, pelo uso do método de difusão em ágar. Os patógenos avaliados foram inoculados em meio Ágar Triptona Soja (TSA) e em seguida bactérias láticas comerciais (ou sobrenadantes provenientes do meio de cultivo) foram colocadas em orifícios realizados no meio TSA e incubadas a 35 ± 2°C por 24 horas. Após este período foram realizadas as medições das zonas de inibição. O maior tamanho de zona de inibição foi observado para as cepas inoculadas em leite em pó a 10%. Após neutralização dos sobrenadantes observou-se que as zonas de inibição desapareceram, indicando que a inibição foi provavelmente devido aos ácidos produzidos pelas bactérias. Os resultados indicam que os meios onde as bactérias láticas foram cultivadas apresentaram diferentes resultados de antagonismo. O uso destes meios de cultivo e os metabólitos produzidos pelas BALs poderão ser utilizado em estudos posteriores, com o objetivo de testar diferentes cepas de bactérias ácido lática com atividade antimicrobiana específica para peixes. ? Abstract: Aeromonas hydrophila and Streptococcus agalactiae are bacteria responsible for the incidence of severe diseases in fishes, causing significant losses in aquaculture. To treat these diseases antibiotics are used which can leave residues in food and cause antimicrobial resistance. Thus, pathogen control and disease prophylaxis should be performed in order to minimize negative impacts on aquatic organisms, humans and the environment. Thereby healthier alternatives have been sought to replace these synthetic molecules and the use of lactic acid bacteria (LABs) and/or their metabolism products is one of them. In this work, we evaluated the antagonistic activity of lactic acid bacteria and their metabolism products grown in two different growth media; 10% milk powder and ?De Man Rogosa & Sharpe? (MRS) plus milk (2%) in powder, against fish pathogens, by using the agar diffusion method. The pathogens were inoculated on Tryptic Soy Agar (TSA) and then commercial lactic acid bacteria (or supernatants from the growth culture medium) were placed in holes made in the TSA medium and incubated at 35 ± 2 ° C for 24 hours. After this period the diameters of the inhibition zones were measured . The largest inhibition zones was observed for the strains growth in 10% milk powder. After neutralization of the supernatants it was observed that the inhibition zones disappeared, indicating that the inhibition was probably due to the acids produced by the bacteria. The results indicate that the media where the lactic bacteria were grown showed different antagonism results. The use of these culture media and the metabolites produced by LABs could be used in further studies with the aim to test different strains of lactic acid bacteria with specific antimicrobial activity for fish. Made available in DSpace on 2019-12-03T00:36:46Z (GMT). No. of bitstreams: 1 PenteadoAvaliacaoAntagonista2019.pdf: 649478 bytes, checksum: 4ad6927c32cbeb831b05709db9224f9d (MD5) Previous issue date: 2019

Bisphenol A and ethinylestradiol, both considered as endocrine disruptors, have been found in surface water and effluents from municipal wastewater supply and can cause adverse health effects on wildlife species and in human beings at extremely low level. In order to remove these compounds from wastewater, constructed wetlands has been used since it proved to be more efficient, and has less cost than conventional treatments. One of the mechanisms of removal of endocrine disruptors by constructed wetlands is the uptake by macrophytes, so it is necessary to analyze these compounds in the plants of the system. Thus, the objective of this study was to develop and validate two methods by high performance liquid chromatography with fluorescence detector capable of determining these compounds in dwarf papyrus and water hyacinth. The evaluated parameters in the validation were: linearity (R 2 ≥ 0.99), limit of detection (LOD = 0.045‐0.15 μg g -1 ), limit of quantification (LOQ = 0.15-1.50 μg g -1 ), accuracy (recoveries from 83.5 to 119.4%) and precision (intra-day CV ≤ 6.2% and inter-day CV ≤ 5.8%). Samples from a constructed wetland were analyzed and the developed methods showed be suitable for intended purpose. Made available in DSpace on 2020-01-17T00:36:12Z (GMT). No. of bitstreams: 1 Queirozdesenvolvimentovalidacao2019.pdf: 1358287 bytes, checksum: 0331d0bce9dce6fe1abcf620bd539806 (MD5) Previous issue date: 2019

The practice of intensive herbicide use in the sugarcane industry has a high risk of compromising the quality of the water and the organisms that live there due to losses through runoff, leaching and other processes. In this work, the dynamics of four herbicides present in three different mixtures were evaluated through their incor- poration and elimination in the muscle tissue of tilapia (Oreochromis niloticus). The highest mean values of bio- concentration factors were 1.730 for ametryn, 0.891 for tebuthiuron, 0.322 for hexazinone and 4.783 for diuron. Diuron presented the highest risk regarding the consumption of tilapia fillets by the population. However, considering that the fish would reach maximum levels of diuron when exposed to extremely high concentrations, an individual weighing 70 kg would need to ingest approximately 1.5 kg of this food product to surpass the acceptable daily intake of 0.007 mg kg 1 body weight. It was concluded that the risk of injury to the population consuming tilapia fillets from fish exposed to herbicides in water arising from sugarcane activities is very low. According to the risk estimation performed in this work, which is substantiated by the assumptions of the World Health Organization and the International Life Sciences Institute, there is a low risk of injury to the population consuming tilapia fillets from fish exposed to water containing herbicides in concentrations arising from sugarcane activities. However, as the risk was estimated from laboratory conditions, caution should be taken where herbicide applications are carried out with high frequency near water bodies, as the consumption of fish from these areas is quite common. Made available in DSpace on 2019-11-26T18:12:26Z (GMT). No. of bitstreams: 1 JonssonBioconcentrationsHerbicides2019.pdf: 322425 bytes, checksum: 2bb57fef778bae7d1b3d6e3250d4c37d (MD5) Previous issue date: 2019

Made available in DSpace on 2019-10-04T12:14:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-01. Added 1 bitstream(s) on 2021-07-15T14:34:53Z : No. of bitstreams: 1 S0001-37652019000300617.pdf: 1313892 bytes, checksum: 5e3289f109193036f6470bbaa59f2809 (MD5) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) We have established how natural compounds from green propolis collected by the species Apis mellifera act against the growth of Pythium aphanidermatum. On the basis of mass spectrometry (Q-ToF MS), we determined that Artepillin C, the major constituent of green propolis, underlies the effect and displays activity against P aphanidermatum at a minimal inhibitory concentration of 750 mu g.mL(-1). Biophysical studies based on model membranes showed that this inhibitory effect may be linked with a membrane-related phenomenon: Artepillin C increases the permeability of membranes with relatively high fluidity in their lateral structure, a feature that is in line with the lipid composition reported for the cytoplasmic membrane of P. aphanidermatum. Therefore, the present study supports the use of the effective and inexpensive green propolis to control the impact of the dangerous phytopathogen P. aphanidermatum on agriculture. Univ Sao Paulo, Fac Filosofia Ciencias & Letras Ribeirao Preto, Dept Fis, Av Bandeirantes 3900, BR-14040901 Ribeirao Preto, SP, Brazil Univ Estadual Paulista, Fac Ciencias & Tecnol, Dept Fis, Rua Roberto Simonsen 305, BR-19060900 Presidente Prudente, SP, Brazil Embrapa Meio Ambiente, Lab Microbiol Ambiental, Rodovia SP 340,Km 127,5, BR-13918110 Jaguariuna, SP, Brazil UNC, CONICET, INIMEC, Inst Invest Med Mercedes & Martin Ferreyra, RA-2434 Cordoba, Argentina Univ Sao Paulo, Fac Med Ribeirao Preto, Dept Genet, Av Bandeirantes 3900, BR-14049900 Ribeirao Preto, SP, Brazil Univ Estadual Paulista, Fac Ciencias & Tecnol, Dept Fis, Rua Roberto Simonsen 305, BR-19060900 Presidente Prudente, SP, Brazil CAPES: 004137/2014-00 FAPESP: 2016/09633-4 CNPq: 305771/2016-7

Demand for organic products is intensified in many countries each year. Following this trend, Brazil produces increasing volumes of organic grape juice. In this way, a survey of organic grape juices made from grapes produced according to this system was carried out where physicochemical composition, minerals, trace elements, and pesticide residues were determined. Variables related to grape juice composition were performed by physicochemical procedures; minerals and trace elements, by inductively plasma optical emission spectrometry; pesticide residues, by liquid chromatography-mass spectrometry. Main results show that the physicochemical composition of organic grape juices was in general in accordance to the Brazilian legislation. The mean concentrations of trace elements were very low, varying from 0.002 (Cd) to 0.970 (Ba) mg L?1. Pesticide residues were not detected in any sample analyzed (MRL= 10 μg L?1). These results show that the Serra Gaúcha viticultural region present conditions to produce organic grape juices, despite the adverse climate factors that occurs in some years. Nevertheless, these products should be made with grape varieties, such as the labrusca ones, less susceptibles to the main grapevine pathogens.

This paper presents an easy and practical procedure to obtain silica-based C-8 type sorbents for use in solid-phase extraction. The materials are prepared by depositing poly(methyloctylsiloxane), PMOS, on the silica support. Two different treatments for immobilization were used: thermal treatment or gamma irradiation. Suitable recoveries were obtained after pre-concentration of dilute solutions, at the ng/L level, of a mixture of pesticides, indicating the good performance of the materials.

A method for the simultaneous determination of diuron and linuron pesticides in human urine was developed, using both solid-phase extraction (SPE) and high-performance liquid chromatography (HPLC) phases made in our own laboratory. These materials were prepared by sorption of polysiloxanes onto a silica surface, followed by immobilization. The HPLC columns were prepared from poly(methyloctylsiloxane), PMOS, immobilized onto silica with microwave radiation while the SPE cartridges where made with poly(methyloctadecylsiloxane), immobilized thermally. Method validation was performed for diuron and linuron for three fortification levels. The recoveries obtained were 85?103%, the inter- and intra-assay precisions were less than 1.6 and 1.8%, respectively. The limits of quantitation and detection for diuron were 2.4 and 8.0 ?g/l and for linuron were 5.0 and 12 ?g/l, respectively. Made available in DSpace on 2017-09-19T00:11:44Z (GMT). No. of bitstreams: 1 PozzebonApplication6383.pdf: 149183 bytes, checksum: afdcb64239f3f5b0f2917d54ef3789c6 (MD5) Previous issue date: 2006-09-29

A sensitive extraction method for the triazines simazine, atrazine, and ametryn was developed and applied to a biological sample (urine). After protein precipitation with acetonitrile, a further purification using solid-phase extraction (SPE) was carried out. The samples were then analysed by high performance liquid chromatography (HPLC) usina a C18 column and an acetonitrile-water (40:60, v/v) mobile phase. The pH of the mobile phase was adjusted to 9.0 with NH4OH, the flow-rate was 0.5 mL/min and UV detection was at 220 nm. Recovery values were satisfactory and the method developed can be used for monitoring urine samples of workers exposed to simazine, atrazine, and ametryn, in forensic, veterinay, and environmental toxicologies. Made available in DSpace on 2017-09-19T00:11:02Z (GMT). No. of bitstreams: 1 PozzebonDevelopment6379.pdf: 111487 bytes, checksum: b55ec0fd481d59bd23c143fd990f95fe (MD5) Previous issue date: 2006-09-28

Column chromatography of the ethyl acetate extract of the seed pod resin of Hymenaea courbaril var. stilbocarpa furnished a fraction containing a mixture of two new clerodanes and a known clerodane diterpene. Due to the similarity of the structures, they could not be separated by ordinary chromatography even using silica gel impregnated with AgNO 3. Thus, an intense study was made in order to optimize the semipreparative separation of this mixture by HPLC (high performance liquid chromatograph) using several different stationary and mobile phases. The best conditions for separation of these diterpenes was on octadecyl-bonded silica with methanol:water:formic acid (85:15:1, v/v/v) as mobile phase, flow rate at 2 mL/min, and UV detection at 240 nm. The fractions obtained were analyzed by gas chromatography-mass spectrometry (GC-MS). Made available in DSpace on 2017-09-19T00:11:49Z (GMT). No. of bitstreams: 1 NogueiraHPLC6384.pdf: 714308 bytes, checksum: ae31550573fb69e37d17c8da72bea169 (MD5) Previous issue date: 2006-09-29

Complexation-induced chemical shifts and diffusion coefficients (HR-DOSY) of enantiomers with native and derivatized cyclodextrins were used for calculations of the apparent binding constants of three cyclohexanone inclusion complexes. Correlations between these data and high-performance liquid chromatography were established, revealing that this approach can be applied as an alternative method to predict enantiomeric discrimination. Made available in DSpace on 2017-09-19T00:12:49Z (GMT). No. of bitstreams: 1 LaverdeNMR6426.pdf: 213925 bytes, checksum: 5e9e39c0711ecb9c0ddcc3229d7cdb9e (MD5) Previous issue date: 2006-10-04

Neste trabalho foi desenvolvido um método visando a "determinação multirresiduos" de pesticidas em água. Onze pesticidas foram estudados: 2,4-D, linuron, diuron, atrazina, ametrina, tebutiuron, simazina, dimetoato, carbendazim, carbaril e 3,4-DCA. Dois métodos de extração e pré-concentração dos pesticidas foram comparados: extração líquido-líquido (ELL) e extração em fase sólida (EFS). Os pesticidas foram analisados em um cromatógrafo a líquido acoplado a um detector espectrométrico de massas; a separação foi realizada usando uma coluna analítica de fase reversa tipo C-18 e eluição com gradiente. A ELL mostrou ser adequada para ser utilizada como técnica de extração e pré- concentração dos analitos, exceto para o carbendazim. A EFS, usando como sorvente o copolímero estireno-divinilbenzeno (Supelclean Envi-chrom P), foi apropriada para a determinação do conjunto de pesticidas estudados, exceto para o linuron. A metodologia foi validada e limites de detecção de 0,1 mg/L ou menores foram encontrados, exceto para a 3,4-DCA e 2,4-D. O detector de massas mostrou ser robusto e possibilitou detectabilidades e seletividades adequadas para análises de rotina. Também foram desenvolvidos materiais do tipo fase reversa, C-8 e C-18, obtidos através do recobrimento da sílica por polissiloxanos, (polimetiloctilsiloxano-PMOS ou polimetiloctadecilsiloxano-PMODS) e imobilização através de diferentes processos: irradiação gama, microondas e temperatura para serem usados em EFS. Estes materiais foram caracterizados através de espectroscopia no infravermelho, análise elementar, análise termogravimétrica e microscopia eletrônica de varredura. Foram estimados os volume de breakthrough para o benomil, tebutiuron, simazina, atrazina, diuron e ametrina. Estes sorventes foram aplicados para análise dos pesticidas em amostras de água nos modos on-line e off-line, e em urina mostrando desempenho tão bom quanto os dos sorventes comerciais. Made available in DSpace on 2020-02-12T18:07:28Z (GMT). No. of bitstreams: 1 2001TSQueirozDeterminacao6262.pdf: 4599553 bytes, checksum: a452d0da3b94561b07f382cde2fb409c (MD5) Previous issue date: 2001 Tese (Doutorado) - Universidade Estadual de Campinas, Instituto de Química, Campinas. Orientador : Isabel Cristina Sales Fontes Jardim.