京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第22489号 / 農博第2393号 / 新制||農||1076(附属図書館) / 学位論文||R2||N5269(農学部図書室) / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 近藤 直, 准教授 小川 雄一, 教授 飯田 訓久 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM

En esta Tesis Doctoral, se aborda la aplicación de metodologías de análisis de datos de múltiples vías, a datos tridimensionales de fluorescencia molecular de excitación-emisión obtenidos a lo largo de una reacción, para obtener de forma rápida información de interés en el desarrollo de técnicas basadas en procesos de eliminación oxidativa de contaminantes orgánicos. Se afrontan dos casos en particular: la foto-degradación de una mezcla de hidrocarburos policíclicos aromáticos (benzo[a]antraceno, benzo[a]pireno, benzo[k]fluoranteno, dibenzo[a,h]antraceno)y la foto-catálisis del fenol. Los espectros de fluorescencia de excitación y emisión registrados para cada muestra analizada constituyen una matriz o datos de segundo orden. Información cualitativa y cuantitativa acerca de las especies que participan en los procesos en estudio se ha extraido trabajando con métodos de análisis multivariante, que permiten analizar datos de múltiples vías como son el método de resolución de curvas basado en el análisis de factores paralelo (PARAFAC)yelbasadoenlaoptimizaciónpormínimoscuadrados(M CR -ALS),asícomoel método de calibración multivariante en mínimos cuadrados parciales para datos de múltiples vías (N -PLS). En la Tesis doctoral se realiza un análisis comparativo de los resultados encontrados por lo diferentes métodos de análisis multivariante. Los resultados encontrados fueron validados al comparar los resultados con los obtenidos cuando el seguimiento cuantitativo se realizaba mediante cromatografía líquida de alta resolución (H PLC), considerada como técnica de referencia para el seguimiento de este tipo de reacciones. La rapidez que aportan estas metodologías es una característica valiosa en estudios de optimización de dichos procesos. En esta Tesis empleando estas metodologías para el cálculo de constantes cinéticas se ha abordado el análisis simultáneo, empleando técnicas de diseño de experimentos, de variables de interés en el desarrollo de los procesos de foto-degradación. Del estudio realizado se derivan los siguientes resultados: *En la foto-degradación de una mezcla de hidrocarburos poli cíclicos aromáticos se evidenció la interacción de las variables experimentales y la importancia del análisis conjunto de sus efectos sobre el proceso para la selección de las condiciones óptimas de trabajo. En el dominio experimental en estudio, se encontró que la degradación es más rápida cuando se trabaja a pH ácido utilizando etanol como solvente e irradiando con una lámpara de baja presión de mercurio. *Tanto al aplicar PARAFAC como M CR -ALS el número de factores significativos fue de cuatro, uno por cada analito presente en la muestra. La bondad de los espectros recuperados en ambos casos fue evaluada calculando el coeficiente de similitud que resultó tener valor superior a 0.98 en todas las situaciones. Cuando los valores de concentración obtenidosenelprocesodedegradaciónmediantePARAFACoM CR -ALSaplicadosadatos EEM fueron representados frente a los obtenidos mediante H PLC se obtuvo una línea de regresión mediante mínimos cuadrados, con pendiente próxima a 1 e intercesión en el origen próxima a 0. El test conjunto de la pendiente y la ordenada en el origen para corroborar la ausencia de sesgo fue superado para todos los analitos. *En la determinación del fenol y sus dihidroxiderivados el error de predicción global tanto para PARAFAC como para M CR -ALS, era admisible y de ello se concluye que es posible realizar un seguimiento rápido y cuantitativo de la concentración del fenol y de la concentración de sus intermediarios, catecol, resorcinol e hidroquinona en un proceso de foto-degradación a partir de sus espectros fluorescentes de excitación-emisión. *El fenol y la hidroquinona se resuelven perfectamente y se obtienen errores bajos a los diferentes niveles de concentración analizados, mientras que catecol y el resorcinol que están fuertemente solapados presentan errores significativamente mayores. * Con el propósito de analizar si los errores encontrados fundamentalmente para el catecol y resorcinol eran susceptibles de mejora, se trabajó con mínimos cuadrados parciales para datos de múltiples vías (N -PLS), en particular tri-PLS1. Los valores encontrados de aplicar este método y los anteriormente descritos a un nuevo conjunto de mezclas representativas del proceso en estudio fueron comparados en términos del error global cometido. *El análisis de los efectos de las variables implicadas en el proceso de degradación en estudio:tipo de catalizador, pH del medio y concentración del sustrato en la constante de velocidad de la reacción permitió concluir que todas ellas interaccionan entre sí y la importancia de sus efectos resultó significativa a un nivel de confianza del 95% cuando se realizó un test estadístico A N O V A . A partir de los resultados encontrados en el desarrollo de esta Tesis, hemos corroborado que la utilización conjunta de la espectrofluorimetría de EEM y la aplicación de diferentes métodos de análisis de datos de múltiples vías, es una opción válida y atractiva para la monitorización cuantitativa de la foto-degradación de una mezcla de hidrocarburos policíclicos aromáticos y de la evolución de la degradación foto-catalítica del fenol y sus intermediarios, así como para el análisis cinético de los procesos estudiados .

Les propriétés hydrophobes des polymères extracellulaires (PEC) exercent l’influence profonde sur les propriétés de la surface cellulaire. Cependant, de nombreux facteurs tels que les méthodes d'extractions, le type de substrat influencent les caractéristiques des PEC et les informations concernant des caractéristiques hydrophobes sont rarement documentées. L'objectif principal de cette étude est de développer une méthode appropriée pour étudier l'hydrophobicité des PEC, puis d'étudier les caractéristiques hydrophobes des PEC.Le fractionnement hydrphobe par la résine Supelite™ DAX-8 a d'abord été appliqué sur les PEC extraits de boues granulaires anaérobies, deux conditions de pH d'élution (pH 2 et 5) ont été testées. L'impact de sept méthodes d'extraction sur les caractéristiques hydrophobes des PEC a été évalué. Les résultats ont montré que les méthodes d'extraction et le pH de la solution extraitante ont influencé la composition des PEC et leur hydrophobicité. En outre, les extraitants des PEC, par exempe le formaldéhyde, l'éthanol, le dodécylsulfate de sodium (SDS) et Tween 20, ont non seulement introduit une teneur supplémentaire en carbone pendant la mesure du carbone organique total (COT), mais ils ont également interagit avec la résine DAX-8. En comparant la répartition du poids moléculaire apparent (aMW) des échantillons des PEC non traités et ajustés au pH détectés par chromatographie d'exclusion stérique (en anglais SEC), l’information plus complète d’aMW a été préservée à pH 5. Ainsi, le fractionnement hydrophobe par la résine DAX-8 à pH 5 et les méthodes physiques d'extraction PEC ont été préférés dans cette étude.Une analyse qualitative détaillée des caractéristiques hydrophobes des EPS a été étudiée par la technique de la matrice de fluorescence d’excitation-emission (EEM). Les résultats ont montré que les substances de type humique (HS-like) représentaient la majorité des composés organiques des PEC extraits de la boue granulaire anaérobie, et constituaient également le principal support moléculaire de l'hydrophobicité des extraits. Ces composés hydrophobes de type HS étaient essenciellement des molécules petites tailles de 8 kDa à <1 kDa. L’hydrophobité contributée par les protéines (PN) et les polysaccharides (PS) présentait un moindre rapport.Afin d’explorer les propriétés hydrophobes de PN et de PS, ainsi évaluer l'impact de l'addition de Ni(II) sur l'hydrophobicité des extraits des champignons, fongi Phanerochaete chrysosporium a été choisi. Les résultats ont montré que la teneur de PN et de PS dans les PEC extrait de ce type de fongi variait en fonction de la concentration de Ni(II). Avec une augmentation de la concentration de Ni de 0 mg/L à 25 mg/L, la teneur en PN a diminué alors que celle de PS a été augmentée. L'hydrophobicité des PEC du fongi, déterminée par le traitement de la résine DAX-8, a diminué lors que la concentration de Ni augmentait. Par ailleurs, l'intensité du pic de SEC correspondant aux molécules PN-like (Ex/Em = 225/345 nm) de 1,9 × 103 à 10 kDa a été augmentée par l'addition Ni; en même temps, la distribution d’aMW des composés organiques totaux (UV/210) dans les PEC restait presque stable. Ces résultats ont indiqué que les composés de type PN-like peuvent avoir déterminé l'hydrophobicité des PEC fongique dans des conditions de stress.Dans l’extrait plus hétérogène des PEC de boues granulaires anaérobies, des composés HS-like représentaient le composant organique majeur, ainsi le principal support moléculaire de l'hydrophobicité des PEC. En étudiant les caractéristiques hydrophobes des PEC extrait du champignon Phanerochaete chrysosporium, le PN et le PS des PEC jouaient un rôle actif dans la protection du champignon sous le Ni. La concentration élevée de Ni a diminué l'hydrophobicité des PEC fongique, mais elle a augmenté l'hydrophobicité de la surface cellulaire du champignon. Il semble que la présence de Ni favorise l'apparition d'un champignon plus hydrophobe / The hydrophobic properties of extracellular polymeric substances (EPS) exert a profound influence on the cell surface properties. However, many factors such as EPS extractions methods, substrate type influence EPS characteristics, and limited information regarding to the hydrophobic features of EPS can be found. The main aim of this study is to develop a proper method to study EPS hydrophobicity, and then investigate the hydrophobic features of EPS.The hydrophobic fractionation by Supelite™ DAX-8 resin was first applied on the EPS extracted from anaerobic granular sludge, two elution pH conditions i.e. pH 2 and 5 were tested. The impact of seven EPS extraction methods on the hydrophobic features of EPS was assessed. The results showed that the extraction methods and bulk solution pH dramatically influenced the EPS composition and their hydrophobicity. Besides, the EPS extracting reagents namely formaldehyde, ethanol, sodium dodecyl sulfate (SDS) and Tween 20 not only introduced extra carbon content during total organic carbon (TOC) measurement, but also interacted with the DAX-8 resin. By comparing the apparent molecular weight (aMW) distribution of the untreated and pH-adjusted EPS samples detected by size exclusion chromatography, more complete EPS aMW information was preserved at pH 5. Thus, the hydrophobic fractionation by DAX-8 resin at pH 5 and physical EPS extraction methods were preferred in this study.After identifying the proper conditions for DAX-8 resin fractionation, detailed qualitative analysis of the EPS hydrophobic features was further investigated. The results showed that the humic-like substances (HS-like) were the major organic constituent of the EPS extracted from the anaerobic granular sludge, and they were also the main molecular support of the EPS hydrophobicity. Those hydrophobic HS-like compounds were mainly small molecules ranging from 8 kDa to <1 kDa. Proteins (PN) and polysaccharides (PS) contributed to the EPS hydrophobicity to a lesser extent.The role of PN and PS in the EPS hydrophobicity was difficult to be shown. It is known that the major organic constituents of the EPS extracted from bacteria, algae and fungi are PN and PS. Therefore, to explore the hydrophobic features of PN and PS, as well as to investigate the impact of Ni(II) addition, on the EPS hydrophobicity, the fungus Phanerochaete chrysosporium was chosen. The results showed that the contents of PN and PS in the extracted fungal EPS varied with the Ni(II) concentration. With an increase in the Ni concentration from 0 mg/L to 25 mg/L, the PN content was decreased whereas the PS content was increased. The fungal EPS hydrophobicity, determined by the DAX-8 resin treatment, was decreased as the Ni concentration increased.Besides, the peak intensity on the size exclusion chromatography (SEC) corresponding to the PN-like molecules (Ex/Em = 225/345 nm) ranging from 1.9×103 to 10 kDa were intensified by the Ni addition, while the aMW distribution of the total organics (UV/210) in the EPS remained almost stable. These results indicated that those PN-like compounds may determine the hydrophobicity of fungal EPS under stress conditions.For the more heterogeneous EPS extracted from anaerobic granular sludge, HS-like compounds were identified as the major organic component, as well as the main molecular support of the EPS hydrophobicity. By studying the hydrophobic features of the EPS extracted from the fungus Phanerochaete chrysosporium, it showed that the PN and PS in the EPS played an active role in protecting the fungus under Ni stress. The increased Ni concentration decreased the hydrophobicity of fungal EPS, but it increased the cell surface hydrophobicity of the fungus. It seems that the presence of Ni promoted the fungus becoming more hydrophobic

Antioxidants are molecules capable of stabilizing and preventing oxidation. Certain peptides, protein hydrolysates, have shown antioxidant capacities, which are obtained once liberated from the native protein structure. Soy protein isolates (SPI) were enzymatically hydrolyzed by pepsin and pancreatin mixtures. The soy protein hydrolysates (SPH) were fractionated with sequential ultrafiltration (UF) and nanofiltration (NF) membrane steps. Heat pre-treatment of SPI at 95 degrees celsius (C) for 5 min prior to enzymatic hydrolysis was investigated for its effect on peptide distribution and antioxidant capacity. SPH were subjected to UF with a 10 kDa molecular weight cut off (MWCO) polysulfone membrane. UF permeate fractions (lower molecular weight than 10 kDa) were fractionated by NF with a thin film composite membrane (2.5 kDa MWCO) at pH 4 and 8. Similar peptide content and antioxidant capacity (α=0.05) were obtained in control and pre-heated SPH when comparing the respective UF and NF permeate and retentate fractions produced. FCR antioxidant capacities of the SPH fractions were significantly lower than their ORAC antioxidant capacities, and the distribution among the UF and NF fractions was generally different. Most UF and NF fractions displayed higher antioxidant capacities when compared to the crude SPI hydrolysates, showing the importance of molecular weight on antioxidant capacity of peptides. The permeate fractions produced by NF at pH 8 displayed the highest antioxidant capacity, expressed in terms of Trolox equivalents (TE) per total solids (TS): 5562 μmol TE/g TS for control SPH, and 5187 μmol TE/g TS for pre-heated SPH. Due to the improvement in antioxidant capacity of peptides by NF at pH 8, the potential for NF as a viable industrial fractionation process was demonstrated. Principal component analysis (PCA) of fluorescence excitation-emission matrix (EEM) data for UF and NF peptide fractions, followed by multi-linear regression analysis, was assessed for its potential to monitor and identify the contributions to ORAC and FCR, two in vitro antioxidant capacity assays, of SPH during membrane fractionation. Two statistically significant principal components (PCs) were obtained for UF and NF peptide fractions. Multi-linear regression models (MLRM) were developed to estimate their fluorescence and PCA-captured ORAC (ORAC-FPCA) and FCR (FCR-FPCA) antioxidant capacities. The ORAC-FPCA and FCR-FPCA antioxidant capacities for NF samples displayed strong, linear relationships at different pH conditions (R-squared>0.99). Such relationships are believed to reflect the individual and relative combined contributions of tryptophan and tyrosine residues present in the SPH fractions to ORAC and FCR antioxidant capacities. Therefore, the proposed method provides a tool for the assessment of fundamental parameters of antioxidant capacities captured by ORAC and FCR assays.

Antioxidants are molecules capable of stabilizing and preventing oxidation. Certain peptides, protein hydrolysates, have shown antioxidant capacities, which are obtained once liberated from the native protein structure. Soy protein isolates (SPI) were enzymatically hydrolyzed by pepsin and pancreatin mixtures. The soy protein hydrolysates (SPH) were fractionated with sequential ultrafiltration (UF) and nanofiltration (NF) membrane steps. Heat pre-treatment of SPI at 95 degrees celsius (C) for 5 min prior to enzymatic hydrolysis was investigated for its effect on peptide distribution and antioxidant capacity. SPH were subjected to UF with a 10 kDa molecular weight cut off (MWCO) polysulfone membrane. UF permeate fractions (lower molecular weight than 10 kDa) were fractionated by NF with a thin film composite membrane (2.5 kDa MWCO) at pH 4 and 8. Similar peptide content and antioxidant capacity (α=0.05) were obtained in control and pre-heated SPH when comparing the respective UF and NF permeate and retentate fractions produced. FCR antioxidant capacities of the SPH fractions were significantly lower than their ORAC antioxidant capacities, and the distribution among the UF and NF fractions was generally different. Most UF and NF fractions displayed higher antioxidant capacities when compared to the crude SPI hydrolysates, showing the importance of molecular weight on antioxidant capacity of peptides. The permeate fractions produced by NF at pH 8 displayed the highest antioxidant capacity, expressed in terms of Trolox equivalents (TE) per total solids (TS): 5562 μmol TE/g TS for control SPH, and 5187 μmol TE/g TS for pre-heated SPH. Due to the improvement in antioxidant capacity of peptides by NF at pH 8, the potential for NF as a viable industrial fractionation process was demonstrated. Principal component analysis (PCA) of fluorescence excitation-emission matrix (EEM) data for UF and NF peptide fractions, followed by multi-linear regression analysis, was assessed for its potential to monitor and identify the contributions to ORAC and FCR, two in vitro antioxidant capacity assays, of SPH during membrane fractionation. Two statistically significant principal components (PCs) were obtained for UF and NF peptide fractions. Multi-linear regression models (MLRM) were developed to estimate their fluorescence and PCA-captured ORAC (ORAC-FPCA) and FCR (FCR-FPCA) antioxidant capacities. The ORAC-FPCA and FCR-FPCA antioxidant capacities for NF samples displayed strong, linear relationships at different pH conditions (R-squared>0.99). Such relationships are believed to reflect the individual and relative combined contributions of tryptophan and tyrosine residues present in the SPH fractions to ORAC and FCR antioxidant capacities. Therefore, the proposed method provides a tool for the assessment of fundamental parameters of antioxidant capacities captured by ORAC and FCR assays.

Dissolved organic matter (DOM) is a complex mixture of organic compounds and represents the largest reservoirs of carbon (C) on earth. Particulate organic matter (POM) is another important carbon component in C cycling and controls a variety of biogeochemical processes. Estuaries, as important interfaces between land and ocean, play important roles in retaining and transforming such organic matter (OM) and serve as both sources and sinks of DOM and POM. There is a diverse array of both autochthonous and allochthonous OM sources in wetland/estuarine ecosystems. A comprehensive study on the sources, transformation and fate of OM in such ecosystems is essential in advancing our understanding of C cycling and better constraining the global C budget. In this work, DOM characteristics were investigated in different estuaries. Dissolved organic matter source strengths and dynamics were assessed in a seagrass-dominated subtropical estuarine lagoon. DOM dynamics controlled by hydrology and seagrass primary productivity were confirmed, and the primary source of DOM was quantified using the combination of excitation emission matrix fluorescence with parallel factor analysis (EEM-PARAFAC) and stable C isotope analysis. Seagrass can contribute up to 72% of the DOM in the study area. The spatial and temporal variation of DOM dynamics was also studied in a freshwated dominated estuary fringed with extensive salt marshes. The data showed that DOM was primarily derived from freshwater marshes and controlled by hydrology while salt marsh plants play a significant role in structuring the distribution patterns of DOM quality and quantity. The OM dynamics was also investigated in a mangrove-dominate estuary and a comparative study was conducted between the DOM and POM pools. The results revealed both similarity and dissimilarity in DOM and POM composition. The dynamics of both OM pools are largely uncoupled as a result of source differences. Fringe mangrove swamps are suggested to export similar amounts of DOM and POM and should be considered as an important source in coastal C budgets. Lastly, chemical characterizations were conducted on the featured fluorescence component in OM in an attempt to better understand the composition and origins of the specific PARAFAC component. The traditionally defined ‘protein-like’ fluorescence was found to contain both proteinaceous and phenolic compounds, suggesting that the application of this parameter as a proxy for amino acid content and bioavailability may be limited.

Spatial and temporal patterns of dissolved organic matter (DOM) were characterized using a combination of spectroluorometric measurements and multivariate analysis techniques. The study was conducted over a four-year (2012-2016) period in multiple watersheds located in the Gulf-Atlantic Coastal Plain Physiographic region of the southeast USA as well as in the Indo-Gangetic Plain of India. Surface water samples were collected from five major lakes in the Mississippi, an estuarine region in the southeastern Louisiana, and from the coastal region in the eastern Mississippi Sound in the USA, and a large river (Ganges River) in India. Absorption and fluorescence measurements were performed to generate absorption spectra and excitation-emission matrices (EEMs). Using parallel factor analyses (PARAFAC), EEM models were developed to characterize the biogeochemistry of DOM in three studies in this project. Principal component analysis and regression analyses of DOM data indicated that the northern Mississippi lakes were majorly influenced by agricultural land use, estuarine region was affected by natural DOM export from forests and wetlands, while the coastal waters were affected by a mix of anthropogenic and natural inputs of DOM. Spatial analyses indicated that DOM derived from watershed with increased wetland coverage was humic and aromatic while the DOM derived from agricultural watersheds was bioavailable. Temporal patterns of DOM in the estuary indicated the influence of hydrologic conditions and summer temperatures, and revealed strong seasonality in DOM evolution in the watershed. During high discharge periods (spring), aromatic and humic DOM was exported from the watershed while strong photochemical degradation during summer resulted bioavailable DOM. Comparison between two river systems, a highly urbanized large river and a small pristine river, indicated the influence of anthropogenic inputs of DOM in the large river system. DOM was bioavailable during summer due to anthropogenic activities in the large river system while it varied with hydrological connectivity in a small river system during summer and winter. In conclusion, this study has improved my understandings of the DOM properties, which are critical for a comprehensive assessment of biogeochemical processes undergoing in important water bodies on which our society is heavily dependent upon.

No description available.

This thesis work is an experimental study of one type of Semi-Solid Metal casting (SSM) process which is called RheoMetalTM. This method is an efficient type of Rheocasting that creates a semi-solid slurry within 30 seconds that is used for a high pressure die casting machine. The purpose of using a slurry in a high pressure die casting machine is that the slurry has a higher viscosity due to its solid fraction. This makes the filling of the die cavity more laminar which reduces air entrapment in the casting. The difficulty with this type of casting is to control the process parameters to be able to insure a casting with desired properties. A few studies within RheoMetalTM has already been made but there is still a lack of knowledge of to what extent the process parameters affect the slurry. The goal in this work is to study how the different RheoMetalTM process parameters influence the primary α-Al solid fraction, shape and size. The process parameters that were studied in this work was the stirring rate, superheat and EEM amount. In this study, the so called growth layer has been removed to make more precise calculations of the primary α-Al. This work also aims to study how grain refinement affect the primary α-Al which is commonly used to improve the quality of castings. To be able to perform this study, both practical and theoretical work has been implemented. The casting process involved making of ladles and preparation of various equipment. The cast samples were then prepared by standard metallurgy procedure for optical analyse of the microstructure. A special etching reagent was used to analyse the microstructure in a microscope. The etching is called Weck’s reagent and its purpose is to differentiate the growth layer from the primary α-Al. The growth layer is formed during quenching and by excluding it, the calculation of the slurry’s primary α-Al becomes more precise. This is because the slurry is not quenched before it is inserted into the high pressure die casting machine, therefore no growth layer is formed. To analyse the cast samples, a special program was used to identify and to calculate the solid fraction, shape and size of the primary α-Al. The result from the calculations made by the program gave different tendencies when changing the EEM amount. The stirring rate showed a tendency to decrease the solid fraction and increase the shape factor. The superheat decreased the solid fraction and increased the shape factor. The grain refinement also decreased the solid fraction and increased the shape factor. There was no clear tendency showing that the equivalent circular diameter of the primary α-Al was affected by any of the parameters.

There is a current lack of accurate tools to determine the concentration of cyanobacteria in situ.  Besides, cyanobacterial blooms have to be carefully monitored in reservoirs as they are more frequent because of climate change and can lead to potential released of toxins, along with other components. This project investigates the possible use of fluorescent probes to measure the concentration of different types of organic matter released by the algae. Three different species of toxic cyanobacteria were chosen to carry out this research as they are representative of the local harmful blooms found across Australia. Furthermore, the efficiency of two different chemicals (powdered activated carbon, also known as PAC, and alum) used in drinking water treatment plants were investigated, in order to determine a method for automatic dosage adjustment in water treatment plant. The organic matter was characterized by LC-OCD and fluorescence spectroscopy and statistical analysis such as principal component analysis was performed on the generated data. General characterization of the different species was firstly performed and globally, similar comportments were observed among the three cyanobacteria species. There is indeed a general increase in the release of organic material throughout the cell’s growth phase. Results from the jar tests showed that PAC mainly targeted humic-like substances and building blocks, which are middle size particles. The average removal rate obtained was 40µg/L per mg/L of PAC added into the water. Therefore, there is indication that the decreased efficiency for the removal of the taste and odor compounds observed in certain plants can be partially attributed to direct competition of organic matter adsorption onto PAC instead of a blockage of the PAC pores by larger particles. On the other hand, alum was able to remove large particles, particularly biopolymers and also humic-substances. However, a great increase of the low molecular weight molecules at very high doses of alum was seen, which suggest that a too high dose of alum is toxic for the algae cells. Based on the bench scale testing the recommended dose of 50 mg/L seems to be optimum for the studied water treatment plant. Specific ultraviolet absorbance and dissolved organic carbon measurements were also investigated and good correlations were found between the concentration of humic-like substances and absorbance, confirming that they are good measure to assess the content of organic matter in the water. However, as the slope coefficient of the linear trend varied between the species, it was not possible to obtain a common conversion factor for all the species. Finally, one fluorophore was found in common to all the samples and is characterized by the excitation-emission wavelength: 240/440 nm. Correlations with the chromatography’s results were investigated and this component seems to match the biopolymers and humic-like substances concentrations. Furthermore, its intensity decreases continuously with the addition of PAC whereas a drop was observed at the lower doses of alum. In regards on these findings, a method for automatic chemicals dosing from the fluorescence measures was proposed. / Detta examensarbete handlar om hur dricksvattenkvalitet kan kontrolleras och övervakas i vattenreningsverk. Nu existerar  inte någon exakt metod för att bestämma koncentrationen av cyanobakterier i vatten då det finns många olika arter. Men det är viktigt att övervaka algers tillväxt in i vattenreningsverk för de kan släppa ut skadliga ämnen till dricksvattnet. De tre arter som studerats i detta projekt är giftiga. Det organiska materialet i råvattnet kan också blockera membranporer eller leda till n biprodukter, som är cancerframkallande. Till sist konkurrerar några organiska substansen med smak- och luktföreningar för adsorptionsställena hos det pulverformiga aktiverade kolet. Därför är smaken och luktföreningarna inte väl borttagna, vilket leder till kundernas klagomål. Cyanobakterier måste övervakas noggrant.                            För att bestämma biologisk och kemisk egenskap hos vatten används flera tekniker för närvarande. I examensarbetet har undersökningar med vätskekromatografi och fluorescensteknik företagits. Kromatografi användes för att klassificera den organiska substansen i mindre grupper: biopolymerer, humus substanser, byggstenar och neutralmolekyler med låg molekylvikt (LMVN). Statistisk analys med R, inklusive huvudkomponentanalys företogs på insamlade data. Fluorescensdata registrerades också och visas i en excitationsutsläppsmatris.                            Experimenten reproducerade en behandlingsprocess och undersökte effektiviteten hos två kemikalier: pulveriserat aktivt kol (PAK) och alun. Resultaten visade att humusämnen   och dess byggstenar var väl borttagna av PAK medan även biopolymerer och humusämnen var väl bortagna av alun. Emellertid var en för hög dos av alun skadlig eftersom det ledde till en ökad frisättning av LMVN. I synnerhert kunde PAK ta bort 40µg/L av både humusämnen och dess byggstenar per mg/L av PAK tillagd. Det föreslår att de är de viktigaste konkurrenterna och att endast direkt konkurrens för adsorptionsställena sker. Om det fanns blockeringsfenomen, skulle det också finnas en minskning för biopolymererna. Den optimala doseringen av alun som bestämdes för det undersökta vattenreningsverket var 50 mg/L. Det kunde ta bort 60-70% av biopolymerer och 40-50% av humusämnen.                            Specifik ultraviolett absorbans och fluorescens registrerades. Båda visade riktigt bra korrelationer med humusämnen, vilket gör de till bra verktyg för att bedöma vattenkvaliteten. Men det kräver fortfarande att arten av cyanobakterie urskiljs eftersom koefficientens lutningar var olika. De kan därför vara ett verktyg för att mäta koncentrationen av organisk material, men arten måste vara känd. Fluorescencedata visade en topp vid 440 nm. En parallellfaktoranalys utfördes på data och endast en komponent hittades gemensam i alla prover. Därför studerades den maximala fluorescensintensiteten hos denna komponent. Å ena sidan kunde vi observera en kontinuerlig minskning av intensiteten när PAK tillsattes. Det är därför möjligt att veta hur man justerar den kemiska doseringen från fluorescensintensiteterna. I slutet av examensarbetet föreslås en metod för automatisk kemisk dosering. Fluorescensprober kan ännu inte exakt indikera cellkoncentrationen. Men med flera sonder som riktar sig till olika våglängder kan de redan vara till stor hjälp för styrning vid vattenverk.