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Oxitetraciclina em tomates e bactericidas agricolas e avaliaçao dos seus residuos em tomates produzidos em estufa e cultura de campo / Oxytetracycline in tomatoes and agricultural antimicrobials and evaluation of residues in tomatoes grown in greenhouse and open fieldMaia, Patricia Penido 09 August 2018 (has links)
Orientador: Felix Guillermo Reyes Reyes / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-09T00:18:19Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: Antimicrobianos como fungicidas e/ou bactericidas têm sido utilizados para a melhoria da qualidade de produtos vegetais destinados à alimentação humana ou para sua maior produtividade em várias fases de sua obtenção, tais como: preparo do solo, crescimento, colheita, industrialização e comercialização. Entretanto, vários destes compostos podem permanecer como resíduos nos alimentos consumidos, e, dependendo de sua toxicidade e nível de exposição, podem apresentar risco à saúde do consumidor. Entre estas substâncias estão os agentes antimicrobianos usados para combater ou prevenir o aparecimento de alterações de origem microbiana no alimento. O desenvolvimento de métodos analíticos para a identificação e quantificação destes agentes em produtos vegetais é de grande interesse, uma vez que a exposição crônica em baixos níveis antimicrobianos pode promover a resistência bacteriana a antibióticos, assim como reações alérgicas. Dessa forma, o presente trabalho objetivou desenvolver metodologia para o isolamento, identificação e quantificação de resíduos de oxitetraciclina em tomate, o qual é muito sensível a bacterioses, assim como comparou os níveis residuais encontrados nos frutos de cultura protegida (estufa) e cultura de campo. A metodologia analítica desenvolvida foi aplicada na análise de tomates comercializados na região de Campinas/SP e Alfenas/MG. Os dados obtidos foram comparados com os limites máximos de resíduos (LMRs) e os intervalos de segurança estabelecidos pela legislação brasileira em condições de plantio no campo. Foi validado, ainda, um método para quantificação dos antibióticos oxitetraciclina e estreptomicina em formulações para uso agrícola utilizadas para tratamento de tomates / Abstract: Antimicrobials as fungicides and/or bactericides have been used for the improvement of the quality of vegetal products destined to the human feed and for its higher productivity in some phases of its cultivation, such as: preparation of the ground, growth, harvest, industrialization and commercialization. However, several of these compounds can remain as residues in consumed foods, and, depending on its toxicity and level of exposure, they can present a risk to the health of the consumer. Among these substances are the antibiotics used to combat or to prevent the appearance of alterations of microbial origin in the food. The development of analytical methods for the identification and quantification of these agents in vegetal products is of great interest, once the chronic exposure to low levels of antimicrobials can promote bacterial resistance to the antibiotics, as well as allergic reactions. Therefore, the present study aimed to develop a methodology for the isolation, identification and quantification of residues of oxytetracycline in tomato, which is very sensible to bacterioses, as well as was compared the residual levels found in fruits cultivated in greenhouse and open field. The developed analytical methodology was applied in the analysis of tomatoes purchased in the region of Campinas/SP and Alfenas/MG. The obtained data were compared with the maximum residue limits (MRLs) and the intervals of security established by the Brazilian legislation in conditions in the field. It was validated a method for quantification of antibiotics oxytetracycline and streptomycin in agricultural formulations used for treatment of tomatoes / Doutorado / Doutor em Ciência de Alimentos
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Novas tecnologias e pre-tratamentos : tomate seco embalado a vacuo / New tecnologies and pre-treatments: vacumm packed dried tomatoCamargo, Gisele Anne 06 January 2005 (has links)
Orientador: Roberto Herminio Moretti / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-04T07:20:31Z (GMT). No. of bitstreams: 1
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Previous issue date: 2005 / Resumo: A concentração osmótica e outros pré-tratamentos visam melhorar a qualidade do produto e otimizar o processo de secagem. Dentre estes tratamentos pode-se citar o uso de antioxidantes para evitar o escurecimento excessivo e manter as características nutricionais. A incorporação de concentrado de tomate com 18 a 36 oBrix, não é um método utilizado na fabricação de tomates secos, e foi um procedimento utilizado com o objetivo de melhorar a qualidade e aumentar o rendimento do processo de secagem. E ainda a utilização de ácidos fracos em soluções utilizadas em desidratação ou concentração osmótica representa uma alternativa de processamento brando. Os objetivos gerais desta pesquisa foram: avaliar e selecionar novas tecnologias e pré-tratamentos, visando melhorar a qualidade do produto final e também aumentar o rendimento e eficiência do processo de secagem de tomate para conserva; e definir e caracterizar a vida de prateleira do produto selecionado. Esta pesquisa definiu procedimentos que permitiram aumentar a eficiência e qualidade de um novo produto: tomates secos, embalados a vácuo com umidade intermediária e com segurança ao consumidor. Foi observado que a utilização de açúcares invertidos permitem maior perda de água e entrada de sólidos no tomate. O ácido ascórbico mostrou perda nos primeiros 30 minutos de pré-tratamento osmótico. O conteúdo de licopeno aumentou a disponibilidade nos primeiros 10 minutos com posterior decréscimo gradual. Os consumidores determinaram que o sabor é o fator mais importante na aceitação do produto e desaprovaram a aplicação de concentrado triplo de tomate como pré-tratamento à secagem. A aplicação de antioxidante (metabissulfito de sódio e ácido isoascórbico) anterior à secagem com ar forçado proporcionou maiores teores de ácido ascórbico e licopeno no produto final. A relação ¿Sólidos Solúveis/Acidez Total¿ escolhida pelo paladar dos consumidores foi de 23,8 a 26,65. A melhor eficiência do pré-tratamento osmótico (solução mista de sacarose e açúcares invertidos) foi obtida quando adicionado sal entre os valores de 5,05 a 7,45% e ácido cítrico entre os limites de 6,62 -7,25%. A preferência sensorial do consumidor foi para os produtos obtidos a partir de concentração osmótica em solução com 65º Brix, com a adição de 5,85% de NaCl e 6,00% de ácido cítrico. A qualidade microbiológica do tomate seco embalado a vácuo foi mantida durante o período avaliado de 180 dias para refrigerado e 90 dias em temperatura ambiente. A construção de isotermas permitiu observar que o armazenamento em umidade relativa superior a 50% proporciona a adsorção de água ao produto, alterando as características originais do tomate seco. Os tomates desidratados osmoticamente com açúcares invertidos, sal é ácido cítrico proporcionaram atividades de água entre 0,76 a 0,86. A reconstituição e reutilização do xarope foi um procedimento eficiente no processo produtivo / Abstract: Osmotic concentration and other pre-treatments aim to improve product quality and optimise the drying process. Amongst these treatments one can mention the use of antioxidants to avoid excessive browning and maintain the nutritional characteristics. The incorporation of tomato concentrate at 18 to 36°Brix is not a method currently used in the manufacture of dried tomatoes, but could be a suitable method for quality improvement as well as increasing the yield on drying, considering that it would add up to six times the amount of soluble solids naturally present in the tomato. And the use of weak acids in the solutions used for osmotic drying or concentration represents a mild processing alternative, resulting in a product with appropriate sensory characteristics for immediate consumption. The use of a combination of additives together with various types of sugar (sucrose, fructose and glucose), especially acidifiers, in addition to their antioxidant action, help to increase the rate of osmosis. The general objectives of this research were: to evaluate and select new technology and pre-treatments aiming at improving final product quality and process yield and efficiency in the drying of tomato, and also to define and characterise the shelf life of the selected product. This research defined procedures, which allowed for an increase in efficiency and quality of a new product: vacuum-packed dried tomato with intermediate moisture content, safe for consumption. The use of invert sugar was shown to increase the efficiency of the osmotic dehydration of tomatoes, and temperatures above 45°C failed to provide the desired quality. Ascorbic acid showed losses during the first 30 minutes of pre-treatment, and the lycopene showed an increase in availability during the first 10 minutes, followed by a gradual decrease. The consumers determined that flavour was the most important factor for product approval and disapproved the application of triple concentrated tomato paste. The application of antioxidant (sodium metabisulphite and isoascorbic acid) allowed for greater retention of the lycopene and ascorbic acid. The consumers preferred products with the ¿soluble solids/total acidity ratio¿ between 23.8 and 26.65. The salt concentration in the mixed syrup of sucrose and invert sugar was shown to be more efficient in the osmotic dehydration process between the values of 5.05 and 7.45%, with a citric acid concentration between 6.62 and 7.25%. The consumers chosen (sensory analysis) products obtained from pre-treatment: osmotic dehydration in 65°Brix syrups with the addition of 5.85% NaCl and 6.00% citric acid. The microbiological quality of the product, vacuum-packed dried tomato, was maintained during the periods evaluated of 180 days under refrigeration and 90 days at room temperature. The consumers considered values for the color parameter ¿L¿ above 38.37 as unacceptable, indicating this value as an instrumental colour limit (luminosity). The dried tomato adsorbed water in Relative Humidity to up 50%. The dried tomatoes osmotically dehydrated with invert sugar, salt and citric acid, provided values for water activity the 0.76 to 0.86. The syrup could be reused efficiently / Doutorado / Tecnologia de Alimentos / Doutor em Tecnologia de Alimentos
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Synthetic studies on the C(1)-C(9) unit of TA toxin using nucleophilic opening of chiral epoxidesFoldvari, Zsuzsanna 12 August 2005 (has links)
TA and TB toxins are host-specific phytotoxins produced by the fungus Altemaria altemata f. sp. Iycopersici, the causative agent of stem canker disease in tomato. The two toxins are similar in structure: TB lacks the C(5) hydroxy group present in TA toxin. Both compounds are isolated as an equilibrium mixture of the two esters formed by either the C(13) or C(14) hydroxy groups of the (2S,4R,5R,11R,13S,14R,15R)-1-amino-11,15¬dimethylhepta-decane-2,4,5, 13, 14-pentol backbone with the Re prochiral carboxy group of tricarballylic acid. The synthesis for these toxins is necessary in order to study their structure-activity relationships. The aim of the synthetic study outlined in this dissertation is the development and implementation of methodology for the synthesis of the C(1)-C(9) unit of the C17 aminopentol backbone of TA toxin with the appropriate stereochemistry. Retrosynthetic analysis of the C17 aminopentol backbone of TA toxin identifies (2R,4S,-5R,6R)-2,6-dimethyloctane-1.4,5-triol, synthon B, and (2S,4R,5R)-1-amino¬nonane-2,4,5,9-tetrol, synthon A as key intermediates for the proposed synthesis. Further analysis of synthon A identifies the C9 synthon (2S,4R,5R)-nonane-1,2,4,5,9-pentol, as the target molecule which can be derived from the C7 synthon (2S,3R)-1,2-epoxyheptane-3,7¬diol. The work presented in this dissertation shows that the protected intermediate corresponding to the abovementioned C7 synthon, can be prepared from 1,5-pentanediol by a number of functional group trans-formations using appropriate protecting group strategy (O-TBS, O-TBDPS and O-benzyl groups) and introduction of the two stereogenic centres by using Sharpless epoxidation/kinetic resolution methodology. Nucleophilic opening of the terminal epoxide using cyanide was successful but using chiral sulfoxide methodology for the introduction of the third stereogenic centre and the concomitant one¬-carbon chain extension, failed: in the case of both an acetonide and a dibenzyl protected C8 intermediate a rearrangement occurred. Alternative methods for nucleophilic opening of the terminal epoxide ring and concomitant or subsequent chain extension were investigated and as a result a different synthetic route is proposed. / Dissertation (MSc (Chemistry))--University of Pretoria, 2006. / Chemistry / unrestricted
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Disinfection by-products and their biological influence on radicle development, biomass accumulation, nutrient concentration, oxidative response and lipid composition of two tomato (Solanum lycopersicum) cultivarsAkande, Babatunde Cornelius January 2016 (has links)
Thesis (DTech (Environmental Health))--Cape Peninsula University of Technology, 2016. / Trihalomethanes are disinfection byproducts of chlorinated waters, and there is a growing interest to understand plant responses to organohalogens. This study investigates the effects of increasing trihalomethane dose on the physiology of tomato (Solanum lycopersicum) and determines whether the extent of physiological impacts of trihalomethane exposure on seedling radicle length, biomass accumulation, concentration levels of 12 key nutrients, oxidative stress, fatty acids and α-tocopherol content in membrane lipids of tomato correlated with either the number of bromine or chlorine atoms in the trihalomethane molecules. The 2 x 4 x 5 factorial experiment was laid out in CRD with four replications. Two cultivars of tomato were exposed to 4 levels of trihalomethanes (bromodichloromethane, bromoform, chloroform and dibromochloromethane) and 5 levels of concentration (0.0, 2.5, 5.0, 7.5, and 10.0 mg.L-1) in a green house. The decrease in seedling biomass and the inhibition of radicle growth increased with increasing trihalomethane concentrations in a dose dependent manner. Also, both these parameters decreased in response to an increase in the number of bromine atoms in the trihalomethane molecule. However, in growing plants the decrease in concentration levels of seven essential nutrients namely nitrogen (N), phosphorus (P), potassium (K), sulphur (S), copper (Cu), zinc (Zn) & boron (B) correlated to an increase in the number of chlorine atoms. Increase in trihalomethane dose also induced a decrease in all the above mentioned nutrients with the addition of manganese (Mn), although the decrease in P and S were not significant at P ≤ 0.05. The increase in trihalomethane dose induced an increase in oxidative stress parameters such as the total phenolic content, ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), ascorbate peroxidase (APX), guaiacol peroxidase (GPX) and lipid peroxidation. The increase in the above parameters correlated to an increase in the number of chlorine atoms, however, no such correlations were observed in superoxide dismutase (SOD) activity, general lipid peroxidation, α-tocopherol content and totalsoluble proteins. In plant membrane lipids, increase in the saturated fat hexadecanoic acid was observed in both tomato cultivars that correlated to the degree of chlorination in the trihalomethane molecule. The increase in α-linolenic acid stress signaling correlated with an increase in the degree of chlorination in only one tomato cultivar suggesting variable tolerance between cultivars to chemical action. Membrane lipids adjustments in tomato plants exposed to increasing trihalomethane dose were based on two factors; first the adjustments of membrane fluidity with the increase in plant sterols and fatty acids content and secondly, the increase in lipophyllic antioxidants such as phenols, quinones and α-tocopherol content. The phenolic lipophyllic antioxidant was tentatively identified to be 2,2’-methylenebis [6-(1,1-dimethylethyl)-4-methyl] phenol. In conclusion, the magnitude of plant responses to trihalomethanes is more dependent on the halogenation number of the molecule and less on its concentration.
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Cucurbitacin chemical residues, non-phytotoxic concentration and essential mineral elements of nemarioc-al and nemafric-bl phytonematicides on growth of tomato plantsBango, Happy January 2019 (has links)
Thesis(M.Sc.( Agriculture, Horticulture)) -- University of Limpopo, 2019 / Worldwide, tomato (Solanum lycopersicum L.) is one of the most important crops grown
for nutritional value and health benefits, and are highly susceptible to root-knot
(Meloidogyne species) nematodes. Following the withdrawal of synthetic chemical
nematicides, Nemarioc-AL and Nemafric-BL phytonematicides have been researched
and developed as alternatives to synthetic chemical nematicides. However, Nemarioc-AL
and Nemafric-BL phytonematicides contains allelochemicals namely, cucurbitacin A
(C32H46O9) and cucurbitacin B (C32H46O8) as their active ingredients. Therefore, the
objective of this study was to determine whether increasing concentration of Nemarioc
AL and Nemafric-BL phytonematicides would result in cucurbitacin residues in tomato
plant, to generate mean concentration stimulation point (MCSP) values, overall sensitivity
(∑k) and selected foliar mineral elements of tomato plant. Two parallel trials of Nemarioc
AL and Nemafric-BL phytonematicides were conducted under field conditions, with each
validated the next season. Each trial had seven treatments, namely, 0, 2, 4, 8, 16, 32 and
64% of Nemarioc-AL or Nemafric-BL phytonematicide concentrations, arranged in a
randomised complete block design (RCBD), with five replications. In each trial, the
seasonal interaction on variables was not significant and therefore data were pooled
across the two seasons (n = 70). In both phytonematicides, the cucurbitacin residues
were not detected in soil and tomato fruit. Plant variables and selected foliar nutrient
elements were subjected to the Curve-fitting Allelochemical Response Data (CARD)
model to generate biological indices which allowed for the calculation of MCSP of
phytonematicides on tomato and their ∑k values of tomato to Nemarioc-AL and Nemafric
BL phytonematicides. In Nemarioc-AL phytonematicide experiment, MCSP for tomato plant variables was at 1.13%, with the ∑k of 60 units, while the MCSP for selected tomato
nutrient elements in leaf tissues was at 2.49%, with the ∑k of 21 units. Plant height,
chlorophyll content, stem diameter, number of fruit, dry fruit mass, dry shoot mass and
dry root mass each with increasing concentration of Nemarioc-AL phytonematicide
exhibited positive quadratic relations with a model explained by 95, 82, 96, 89, 83, 83 and
92%, respectively. Similarly, K, Na and Zn each with increasing Nemarioc-AL
phytonematicide concentration exhibited positive quadratic relations with a model
explaining a strong relationship by 91, 96 and 89%. In Nemafric-BL phytonematicide
experiment, MSCP for tomato plant variables was at 1.75%, with the ∑k of 45 units,
whereas MCSP for selected tomato nutrient elements in leaf tissues was at 3.72% with
the ∑k of 33 units. Plant height, chlorophyll content, stem diameter, number of fruit, dry
fruit mass, dry shoot mass and dry root mass and increasing Nemafric-BL
phytonematicide concentration exhibited positive quadratic relations with the model
explaining a strong relationship by 92, 83, 97, 96, 87, 94 and 96%. Likewise, Na and Zn
each with increasing Nemafric-BL phytonematicide concentration exhibited positive
quadratic relations with a model explaining their relationship by 93 and 83%, respectively.
In contrast, K with increasing Nemafric-BL phytonematicide concentration exhibited
negative quadratic relations with a model explaining the relationship by 96%. In
conclusion, tomato plant variables and selected foliar nutrient elements over increasing
concentration of phytonematicides exhibited DDG patterns, characterised by three
phases, namely, stimulation, neutral and inhibition. The developed non-phytotoxic
concentration would be suitable for successful tomato production under field conditions.
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Demand for fresh tomatoes in CanadaBrown, Maxwell L., 1931- January 1967 (has links)
No description available.
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Strategy for the optimal climate control of greenhouse tomatoesTrigui, Maher. January 2000 (has links)
No description available.
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Rapid Assessment of Quality Parameters in Processing Tomatoes using Handheld and Bench-top Infrared Spectrometers and Multivariate AnalysisWilkerson, Elizabeth Dalee January 2012 (has links)
No description available.
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Resistance of different tomato varieties (Lycopersicon esculentum) to late blight (Phytophthora infestans) in laboratory conditions at UAC Carmen Pampa, in the province of Nor Yungas, department of La PazFlorez Paxi, Andrez Faustino 01 January 2008 (has links) (PDF)
In order to respond to the low economic and harvesting yields caused by diseases that attack the tomato, we considered using tomato varieties resistant to late blight (Phytophthora infestans) of tomato (Lycopersicon esculentum) and potato (Solanum tuberosum). The evaluation of the percentage of infestation was performed with tomato leaflets over a 168 hour period. The percentage of infestation was recorded every eight hours from the time of inoculation until maximum infestation was reached. The methodology applied was at random and included six treatments and five replications. The experiment consisted of collecting healthy leaflets from five improved varieties and one local variety of tomato. After collection, the leaflets were disinfected and inoculated in petri dishes on both sites of the midrib with Phytophthora infestans at concentrations of 1 x 107 conidium/mL. The commercial variety (Santa Cruz Kada Gigante) presented the lowest average infestation rate (50%) during the evaluation stage from time of inoculation up until 120 hours. After 120 hours, the leaflets of this variety also reached maximum infestation. A comparison of the study conditions to the scale of resistance values shows it must belong to a moderately resistant variety with horizontal resistance genes to this fungal disease.
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Technological Processing of the Tomato (Lycopersicum esculentum) and the Project of Industrial ViabilityRico Aranibar, Luis Alberto 01 January 1998 (has links) (PDF)
Technological Processing of the Tomato (Lycopersicum esculentum) and the Project of Industrial Viability by Luis Alberto Rico Arabinar. The present investigation was carried out to determine the aptitude of two varieties of tomatoes in the process of manufacturing concentrations, as well as quantify its loses and performance and evaluate the acceptance and the quality of the product through organoleptic and microbiological analysis. This consists of two parts: First- The laboratory investigation consisted in the elaboration of tomato concentrations. This was done with two varieties, Rio Fuego and Santa Clara, three soluble solid concentrations (10, 20, and 30º brix), and two types of thermal pressure treatment (washing with water at 89º C for 30 minutes and pressure cooking at 110º C for 10 minutes). This was followed by a microbiological analysis, and an organoleptic evaluation of the product. The two tomato varieties were found to adapt as fresh fruit as well as for industry. On the other hand, the organoleptic characteristics of the final product (concentration) presented satisfactory results (5.5/7 points) concerning the test panel; the treatments of 20 brix were the most accepted. The microbiological analysis of the concentration demonstrated the product's sanitary quality. Second-The industrial viability of the project was, in part, carried out while visiting the Omerque Zone and trying to understand its problems of production, commercialization, etc. As well as present a manufacturing presentation of the concentrations in the before said zone. After performing a technical and financial feasibility study, it was determined that the study would prove to be profitable according to VAN (valor actualizado neto) and the TIR (tasa interna de retorno). VAN= $16,717.60 US, TIR= 20.30% (without external financing). VAN= $16,346.80 US, TIR= 25.01% (with external financing). Key Words: Tomato, Concentration, Processing, and Project.
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