O desenvolvimento e implementação de uma estratégia de manejo integrado de doenças na cultura do girassol (Helianthus annuus) requer informações precisas e acuradas sobre os danos causados pela mancha de Alternaria, causada por Alternaria helianthi. Os objetivos desta tese foram: elaborar e validar uma escala diagramática para avaliação da mancha de Alternaria; determinar a influência da temperatura (15-32,5 °C) e da duração do período de molhamento foliar (2-24 h) nos componentes monocíclicos da doença; comparar a relação de variáveis relacionadas à doença ou à área foliar com os componentes de produção de girassol, em experimentos de campo. A escala diagramática, com níveis de severidade de: 0,03; 0,2; 0,6; 3; 7; 12; 25; 40 e 66% da área foliar lesionada, foi validada por três avaliadores experientes. A escala permitiu que se fizesse uma avaliação acurada e precisa, quando se utilizou folhas desenhadas ou folhas verdes com sintomas. O erro absoluto ao estimar a severidade foi menor que 13% e a reprodutibilidade das avaliações foi alta. Em ambiente controlado, verificou-se que a densidade relativa de lesões e a severidade foram influenciadas pela temperatura e pela duração do período de molhamento foliar. A doença foi mais severa na temperatura de 25 °C. A temperatura mínima para desenvolvimento da doença foi de 13,0 °C e a máxima foi de 35,8 °C. A doença aumentou com o aumento da duração do período de molhamento foliar. A temperatura mínima estimada para a taxa de crescimento micelial foi de 5,5 °C e a máxima foi de 32,9 °C. A temperatura mínima estimada para germinação de conídios foi de 7,9 °C e a máxima foi de 40,0 °C. Experimentos foram conduzidos nas safras de 1997/1998, 1998/1999 e 1999/2000 para avaliar a relação entre severidade da mancha de Alternaria, área sob a curva de progresso da doença (AUDPC), índice de área foliar sadia em determinado dia (HLAI), duração da área foliar sadia (HAD), radiação interceptada pela área foliar sadia em determinado dia (HRI), absorção da área foliar sadia (HAA) e componentes de produção de girassol, semeado em quatro épocas. A AUDPC teve relação com rendimento de aquênios, com ajuste do modelo exponencial negativo em duas safras. A relação rendimento x HAD foi linear para os três experimentos. Para as variáveis integrais estudadas, a melhor relação com rendimento foi verificada para HAA, com ajuste do modelo exponencial. A taxa da relação severidade x rendimento tendeu a se estabilizar a partir da fase de desenvolvimento R1. A taxa da relação linear entre HLAI e rendimento estabilizou-se entre as fases R1 a R6. A taxa da regressão entre HRI e rendimento foi bastante variável e não mostrou tendência de estabilização. Verificou-se que plantas que apresentaram severidade maior que 10% na fase de desenvolvimento R3 produziram rendimentos inferiores a 500 kg/ha, para as três safras, independentemente da época de semeadura, o que pode ser utilizado como um limiar de dano. A severidade pode ser usada como uma variável independente para um sistema de manejo da mancha de Alternaria em girassol. / The development and implementation of integrated disease-management system on sunflower (Helianthus annuus) require precise and accurate information on the damage caused by Alternaria leaf spot (Alternaria helianthi). The objectives of this thesis were: to develop and to validate a diagrammatic scale for Alternaria leaf spot; to determine the influence of temperature (15-32.5 °C) and leaf wetness duration (2-24 h) on the monocycle of the disease; and to compare the relationship between variables related to Alternaria leaf spot or to leaf area and yield, in field experiments. The diagrammatic scale with levels representing: 0.03; 0.2; 0.6; 3; 7; 12; 25; 40; and 66% of diseased leaf area was validated by three experienced raters. The scale permitted assessments to be accurate and precise, when drawn or detached leaves were used. The absolute error in estimating disease severity was lower than 13% and the reproduc ibility of assessments was high. In controlled environment studies, relative lesion density and severity were influenced by temperature and leaf wetness duration. The disease was more severe in the temperature of 25 °C. The minimum temperature for disease development was 13.0 °C and the maximum was 35.8 °C. The disease increased with increasing periods of leaf wetness. The estimated minimum temperature for mycelial growth rate was 5.5 °C and the maximum was 32.9 °C. The estimated minimum temperature for conidia germination was 7.9 °C and the maximum was 40.0 °C. Three field experiments were carried out in 1997/1998, 1998/1999 and 1999/2000 to investigate the relationship between severity of Alternaria leaf spot, area under disease progress curve (AUDPC), healthy leaf area index at any given day (HLAI), healthy leaf area duration (HAD), radiation intercepted by healthy leaf area at any given day (HRI), total healthy leaf area absorption (HAA), and yield components of sunflower, sowed in four dates. AUDPC showed relationship with yield in two years, following the negative exponential model. The yield x HAD relationship was linear for each of three trials. Among the integral variables analyzed, the yield x HAA relationship was the best one, fitted by the exponential model. The slope of the yield-severity relationship was stable from R1 growth stage. The yield-HLAI relationship was stable between R1 and R6. The yield-HRI relationship was variable and not stable. The yield-severity relationship in R3 growth stage proved that plants with severity higher than 10% had yield lower than 500 kg/ha, despite the sowing date, which can be used as a damage threshold. Severity can be used as an independent variable to a system of sunflower Alternaria leaf spot management.

Durante anos, a manteiga foi muito apreciada pelo consumidor, mas por conter grande quantidade de ácidos graxos saturados e colesterol, seu consumo tem diminuído. Recentemente, a descoberta dos malefícios causados pelos ácidos graxos trans presentes nas margarinas produzidas por hidrogenação parcial aumentou o interesse por métodos alternativos de modificação de lipídios. Assim, o objetivo deste trabalho foi desenvolver um lipídio estruturado à base de gordura do leite que apresentasse maiores teores de ácidos graxos insaturados que a manteiga original e, consequentemente, melhor espalhabilidade, além de conter fitosteróis, constituindo a base de um alimento funcional com capacidade de reduzir os níveis de colesterol no sangue. Foram realizadas misturas da gordura do leite (GL) com óleo de girassol (OG) e ésteres de fitosteróis (EF) e foi efetuada interesterificação química e enzimática. As misturas e os lipídios estruturados obtidos foram analisados quanto a composição em ácidos graxos, consistência, conteúdo de gordura sólida (CGS), cinética de cristalização e estrutura cristalina, entre outras propriedades físico-químicas. Foram obtidos produtos contendo cerca de 60% de ácidos graxos insaturados pela adição de até 40% de OG e 25% de EF à gordura do leite, que originalmente possuía cerca de 33% de ácidos graxos insaturados. A interesterificação química melhorou a plasticidade das misturas, enquanto que a modificação enzimática não modificou de maneira expressiva sua consistência. A adição de pequenas quantidades de OG à GL provocou grande diminuição de sua consistência, enquanto que a diminuição do CGS ocorreu em proporções semelhantes às esperadas por interpolação linear. A edição de vídeos que permitam a observação da formação da estrutura cristalina de gorduras mostrou ser uma ferramenta de grande utilidade no estudo da cristalização de óleos e gorduras. A emulsão preparada com a mistura contendo 25,0% de EF, 7,5% de OG e 67,5% de GL apresentou diminuição expressiva na consistência quando comparada à manteiga, representando um efeito benéfico. / For many years, butter has been held in the highest esteem by consumer but its world consumption has steadily declined due to its high contents of saturated fatty acids and cholesterol. More recently, trans fatty acids, which are commonly resent in hydrogenated argarines, have been found to cause detrimental effects when consumed in high amounts. This observation has increased the interest in alternative methods of lipid modification. Therefore, the objective of this work was to develop a milkfat based structured lipid, presenting higher contents of unsaturated fatty acids than original butter and consequently better spreadability, besides containing phytosterols and serving as a base of a functional food with a cholesterol lowering health claim. Blends containing milkfat (MF), sunflower oil (SO) and phytosterol esters (PE) were prepared and then chemically and enzimatically interesterified. The fatty acid composition, consistency, solid fat content (SFC), crystallization kinetics and crystal structure, among other physical and chemical properties were analyzed. The blends presented about 60% of unsaturated fatty acids with the addition of up to 40% of SO and 25% of PE to MF, which originally presented close to 33% of unsaturated fatty acids. Chemical interesterification improved the plasticity of the blends, while the enzymatic reaction did not substantially alter it. The addition of small amounts of SO and PE to MF caused a great decrease in its consistency, while SFC decreased almost proportionally to the addition of these components. The edition of videos made possible the observation of crystal structure formation and it represented a tool of great importance in the fats and oils crystallization research. The emulsion prepared with the blend containing 25.0% of PE, 7.5% of SO, and 67.5% of MF presented a substantial improvement in consistency when compared to butter commercially available.

<p>Aktuelni problem industrije proizvodnje hrane za ribe jeste smanjena dostupnost i visoka<br />cena ribljeg bra&scaron;na, tradicionalnog izvora proteina u hrani za ribe, koja je direktna posledica rasta sektora akvakulture i visoke potražnje za ovim kvalitetnim proteinskim hranivom. Delimična ili potpuna zamena ribljeg bra&scaron;na visokoproteinskim sirovinama biljnog porekla u recepturama za ishranu riba, uz iznalaženje novih alternativnih visokoproteinskih sirovina pristup je kojim se prevazilazi ovaj problem i koji ima potencijal da obezbedi održivost celokupne industrije hrane za ribe u budućnosti. U okviru ove disertacije predloženo je novo, relativno jednostavno i jeftino tehnolo&scaron;ko re&scaron;enje za suvo frakcionisanje suncokretove sačme, čijom bi se primenom dobile njene visokoproteinske frakcije kao potencijalne proteinske sirovine biljnog porekla za zamenu ribljeg bra&scaron;na u hrani za ribe. Shodno tome, istraživanja ove disertacije urađena su u dve odvojene faze, gde je prva, faza vazdu&scaron;ne klasifikacije, imala za cilj ispitivanje mogućnosti primene kombinacije postupaka usitnjavanja suncokretove sačme mlinom čekidarom i vazdu&scaron;ne klasifikacije ovako usitnjene sačme primenom vazdu&scaron;nog gravitacionog kaskadnog, cik-cak, klasifikatora u cilju dobijanja frakcija povedanog sadržaj proteina u odnosu na polaznu sačmu. Nezavisni parametri usitnjavanja i klasifikacije bili su prečnik otvora sita (POS) čekidara (3, 2 i 1 mm), protok<br />klasifikacionog vazduha (5, 8,7 i 12,5 m³/h) i jačina oscilacije vibro dozatora (JOVD)<br />klasifikatora (30, 60 i 90% maksimuma). Zavisne promenljive bile su sadržaj proteina u<br />dobijenim frakcijama i njihov prinos. Primenjen je 3x3x3 potpuni faktorijalni eksperimentalni dizajn prema metodi odzivne povr&scaron;ine. U cilju dobijanja frakcije sa &scaron;to<br />većim sadržajem proteina, u &scaron;to većem prinosu, kombinacija postupaka usitnjavanja i<br />vazdu&scaron;ne klasifikacije je optimizovana primenom regresione analize, analize glavnih<br />komponenata (PCA analiza), analize varijanse, kao i računske dinamike fluida (CFD analiza), kojom je dobijeni kompjuterski model vazdu&scaron;ne klasifikacije suncokretove sačme poređen sa eksperimentalno dobijenim rezultatima. Cik-cak vazdu&scaron;ni klasifikator uspe&scaron;no je primenjen za razdvajanje usitnjene suncokretove sačme na grubu i finu frakciju. Pri povećanju protoka vazduha smanjivao se prinos grube a istovremeno povećavao prinos fine frakcije. Grube frakcije suncokretove sačme dobijene pri protocima vazduha od 8,7 i 12,5 m³/h imale su za 0,5 &minus; 41,4% relativno veći sadržaj proteina u poređenju sa polaznom sačmom. Smanjenje POS i povećanje protoka vazduha uticalo je na povećanje, dok je povećanje JOVD, uticalo na smanjenje sadržaja proteina grube frakcije. Najveći sadržaj proteina (50,90%SM) imala je gruba frakcija suncokretove sačme dobijena pri sledećim parametrima: POS &minus; 1 mm; protok vazduha &minus; 12,5 m³/h; JOVD &minus; 30%. Na sadržaj proteina grube frakcije i odnos prinosa frakcija značajan uticaj (p &lt; 0,05) imali su POS čekidara i protok vazduha, dok je CFD model pokazao zadovoljavajuće poklapanje sa eksperimentalnim rezultatima. Cilj druge faze disertacije, faze ekstrudiranja, bio je najpre ispitivanje uticaja dodatka polazne suncokretove sačme (oko 37% proteina na SM) i njene dve visokoproteinske frakcije (oko 43% i 49% proteina na SM), dobijenih na osnovu odabranih parametara usitnjavanja i vazdu&scaron;ne klasifikacije, na postupak ekstrudiranja i fizički kvalitet ekstrudirane hrane za ribe. Maksimalno 20% ribljeg bra&scaron;na bilo je zamenjeno polaznom sunockretovom sačmom i njenim odabranim visokoproteinskim frakcijama, a njihov udeo u recepturi za ishranu pastrmke menjan je na osnovu dizajna sme&scaron;e. Za ekstrudiranje eksperimentalnih sme&scaron;a i dobijanje hrane u obliku granula kori&scaron;ćen je dvopužni ekstruder. Ulazni parametri ekstrudiranja bili su konstatni, osim sastava sme&scaron;e, a<br />praćeni su izlazni parametri ekstrudiranja: temperatura u cevi ekstrudera, temperatura<br />matrice, pritisak na matrici, specifična potro&scaron;nja energije (SME) i obrtni moment<br />elektromotora ekstrudera. Proizvedenim uzorcima ispitani su pokazatelji fizičkog kvaliteta: stepen ekspanzije, nasipna masa, tvrdoća, stepen otiranja, kapacitet upijanja ulja, nivo otpu&scaron;tanja ulja iz zauljenih granula, stabilnost u vodi i mikrostruktura granula. Prisutvo suncokretove sačme vi&scaron;eg sadržaja proteina i manjeg sadržaja celuloze u sme&scaron;i uticalo je na formiranje vi&scaron;e temperature matrice ekstrudera, kao i na smanjenje SME i obrtnog momenta. Povećanje sadržaja proteina suncokretove sačme doprinelo je stvaranju kompaktnije strukture granule, povećanju tvrdoće, otpornosti otiranju i stabilnosti granula u vodi, smanjenju nivoa otpu&scaron;tanja ulja, te je tako pozitivno uticalo na fizičke karakteristike granula. Visokoproteinska frakcija suncokretove sačme sa 49% proteina na SM doprinela je optimalnim fzičkim karakteristikama ekstrudirane hrane za pastrmku. Karakterizacija ove frakcije kao potencijalne nove sirovine u industriji hrane za ribe bio je krajnji cilj ispitivanja ove disertacije. U tu svrhu navedena frakcija suncokretove sačme poređena je u novom eksperimentu ekstrudiranja i ispitivanja fizičkog kvaliteta hrane za pastrmku sa ribljim bra&scaron;nom, kao i sojinim bra&scaron;nom, koje je najče&scaron;će kori&scaron;ćen izvor biljnih proteina u hrani za ribe. Kori&scaron;ćena je nova receptura sme&scaron;e ali ista postavka eksperimenta kao u prvom delu faze ekstrudiranja. Rezultati su pokazali da je prisustvo visokoproteinske suncokretove sačme sa oko 49% proteina (SM) doprinelo smanjenju temperature matrice, ali i povedanju SME i obrtnog momenta, a time i poroznosti granula &scaron;to je imalo pozitivan uticaj na kapacitet upijanja ulja granula, stabilnost granula i otpu&scaron;tanje nutrijenata u vodi, kao i negativan uticaj na stepen otiranja i nasipnu masu granula. Zamena 13,4% ribljeg bra&scaron;na u recepturi ovom viskoproteinskom frakcijom suncokretove sačme za rezultat je imala granule zadovoljavajućeg fizičkog kvaliteta. Granule najboljeg fizičkog kvaliteta dobijene su<br />kombinacijom visokoproteinske frakcije suncokretove sačme sa sojinim bra&scaron;nom, te se<br />moglo zaključiti da se funkcionalne karakteristike ove dve sirovine odlično dopunjuju, i da visokoproteinska frakcija suncokretove sačme, sa stanovi&scaron;ta tehnolo&scaron;kog kvaliteta hrane za ribu, predstavlja dobru alternativu ribljem bra&scaron;nu.</p> / <p>High price and finite availability of fish meal (FM), due to high expansion of aquaculture<br />sector in recent decades, are main concerns for modern day aquafeed industry. Partially or completely substation of fish meal in fish feed with protein sources of plant origin, together with finding novel alternative protein sources, is commonly used approach that enables sustainability of aquafeed industry in decades to come. New, relatively simple and low-cost procedure for dry fractionation of sunflower meal (SFM) was proposed within this thesis, with aim for producing high protein SFM fractions as a potential plant source alternative for FM in fish feed. Thus, thesis&rsquo;s researches were done in two phases, where the aim of the first phase, air classification phase, was to investigate the possibility of applying combination of grinding by hammer mill and air classification of ground SFM using gravitational, cascade air classifier (zigzag), in order to obtain protein enriched fractions. Independent variables of grinding and air classification were sieve openings diameter (SOD) of hammer mill (3, 2 and 1 mm), air flow (5, 8.7 and 12.5 m3/h) and bowl feeder oscillation rate (BFOR) of air classifier (30, 60 and 90% of the maximum). Depended responses were protein content and yield of obtained fractions. The experimental data were obtained using 3 x 3 x 3 full factorial experimental design according to response surface methodology (RSM). For the optimization of grinding and air classification, in order to obtain fraction with highest possible protein content and in high yield, regression analysis, principal component analysis (PCA), analysis of variance (ANOVA) and computational fluid dynamics (CFD) approach were employed. Zigzag air classifier was successfully used for fractionation of ground SFM into coarse and fine fraction. Yield of coarse fractions was decreasing, while fine fractions yield was increasing with the increase of the air flow. Coarse fractions of SFM obtained at 8.7 and 12.5 m3/h were 0.5 &minus; 41.4% relatively enriched in protein content compared to the starting SFM. Decrease of SOD and increase of air flow resulted in coarse fraction protein content increase, while increasing BFOR decreased coarse fraction protein<br />content. The coarse SFM fraction with highest protein content was obtained for the SFM<br />ground by 1 mm SOD, air flow of 12.5 m3/h, with BFOR set at 30%. Protein content of<br />coarse fraction and ratio of fractions yields were significantly affected (p &lt; 0.05) by SOD of hammer mill and air flow. CFD model coincide with the experimental results of air<br />classification. The first aim of second phase, extrusion phase, was to investigate influence of starting SFM (37% of protein at DM) and its two high protein fractions (43% and 49% of protein at DM), obtained by grinding and air classification, on extrusion process and physical quality of extruded fish feed. Maximum 20% of FM was substituted with SFM and its high protein fractions in trout feed recipe, and their share was changed according to the<br />mixture design. Twin screw extruder was used for the production of trout feed samples.<br />Primarily extrusion parameters were constant, except dry mixture composition, and<br />secondary extrusion factors were observed: extruder barrel&rsquo;s temperatures, temperature<br />and pressure at the die, specific mechanical energy (SME) and motor load as torque.<br />Selected physical properties of extruded trout feed samples were determined: radial<br />expansion, bulk density, hardness, durability, oil absorption capacity, oil leakage, water<br />stability and microstructure of feed. SFM higher in protein and lower in fiber influenced<br />higher die temperature and lower SME and torque during extrusion process. Increase in<br />protein content of SFM resulted in more compact structure of pellets, increased hardness, durability and water stability, decreased oil leakage and thus positively influenced on physical properties of feed. High protein SFM fraction with around 49% of protein (DM) contributed to the optimal physical properties of experimental feed and characterization of this SFM fraction, as a potential new raw material in fish feed industry, was definite aim of this thesis. Towards that, new set of experiments was conducted, where high protein SFM fraction was compared with FM and soybean flour (SBF) by extruding new samples of trout feed and investigating their physical quality. Results of second extrusion experiment showed that presence of high protein SFM fraction (49% of protein DM) in dry mixture decreased die temperature, while increased SME and torque, and with that also increased porosity of pellets, oil absorption capacity and water stability but decreased bulk density and durability. Substitution of 13.4% FM by high protein SFM fraction resulted in pellets with satisfactory physical quality. The highest quality pellets were obtained in combination of high protein SFM and SBF, which lead to the conclusion that functional characteristics of high protein SFM fraction and SBF are complementary, and that novel SFM, from the point of technical quality, presents good FM alternative.</p>

La sélection génomique (GS) est un outil puissant pour prédire les phénotypes ou les valeurs génétiques d'individus encore non observés, sur la base d'un panel à la fois phénotypé et génotypé. Les modèles mixtes GBLUP habituellement utilisés prennent en compte tous les marqueurs simultanément, en postulant que leurs effets suivent tous la même distribution gaussienne. Les connaissances des mécanismes biologiques sous-jacent à la variation phénotypique ne sont donc pas pris en compte dans une telle modélisation. Le but de cette thèse est d'intégrer dans des modèles GBLUP des connaissances a priori, comme des régions génomique impliquées dans la variation des caractères d'intérêt ou encore des réseaux de gènes, afin d'évaluer le potentiel d'amélioration de la précision de prédiction. Ces modèles ont été appliqués à l'espèce de tournesol Helianthus annuus L., sur trois caractères (la floraison, le rendement et la sénescence foliaire) dans 13 environnements différents. L'un des principaux défis des études sur les hybrides de tournesol est de modéliser la vigueur hybride, ou hétérosis. Différentes hypothèses, incluant la dominance, la superdominance et l'épistasie ont été proposées pour clarifier les mécanismes génétiques sous-jacents au phénomène de l'hétérosis, mais leur importance n'est pas clairement connue. Dans ce contexte, la première partie de cette étude a eu pour but de tester l'efficacité de la GS dans une population d'hybrides provenant du croisement de 36 lignées femelles avec 36 lignées mâles. Pour cela des modèles prenant en compte des effets non-additifs ont été expérimentés, et les résultats validés expérimentalement en champ sur deux années. La prédiction des valeurs génétiques des hybrides ayant été concluante, nous avons ensuite cherché des informations a priori à intégrer à ces modèles. Des SNPs impliqués dans la variation des trois caractères d'intérêt ont été recherchés à l'aide de plusieurs modèles de GWAS (additifs et non-additifs). De plus, dans la perspective de tester des modèles prenant en compte des interactions épistatiques, des SNPs localisés dans des réseaux de gènes connus ont été recherchés. La dernière partie de cette thèse a eu pour but d'intégrer aux modèles GBLUP ces régions génomiques impliquées dans la variation des caractères. Deux méthodes ont été utilisées pour cela, à savoir la modélisation des informations a priori dans la partie aléatoire (modèle MultiBLUP) ou dans la partie fixe des modèles. Ces méthodes ne montrent pas d'amélioration significative des précisions de prédiction par rapport aux modèles GBLUP sans information a priori. / Genomic selection is a powerful tool for predicting phenotypes or genetic values of non-observed individuals, based on a panel both phenotyped and genotyped. The mixed models GBLUP usually utilized take into account all markers simultaneously, assuming that all their effects all follow the same Gaussian distribution. Knowledge of the biological mechanisms underlying phenotypic variation is therefore not taken into account in such modeling. The aim of this thesis is to integrate in GBLUP models a priori knowledge, such as genomic regions involved in the variation of the traits of interest or networks of genes, in order to evaluate the potential for improvement of accuracies. These models were applied to the Helianthus annuus L. sunflower specie on three traits (flowering time, yield and leaf senescence) in 13 several environments. One of the main challenges of genetic studies on sunflower hybrids is to model hybrid vigor, or heterosis. Different hypotheses, including dominance, over-dominance and epistasis have been proposed to clarify the genetic mechanisms underlying the heterosis phenomenon, but their importance is not clearly known. In this context, the first part of this study aimed to test the efficiency of the GS in an hybrid population from the crossing of 36 female lines with 36 male lines. For this purpose, models taking into account non-additive effects were experimented, and the results validated experimentally in field over two years. The prediction of the genetic values of the hybrids was conclusive, so we looked for a priori information to integrate with these models. SNPs involved in the variation of the three traits of interest were searched using several models of GWAS (additive and non-additive). Moreover, in order to test models taking into account epistatic interactions, SNPs located in known gene networks have been sought. Finally the integration of the genomic regions involved in the variation of the traits, into the GBLUP models, was conducted. Two methods were implemented for this, namely the modeling of a priori information in the random part (MultiBLUP model) or in the fixed part of the models. These methods do not show significant improvement in accuracies compared to GBLUP models without a priori information.

Thesis (M.Dev.) --University of Limpopo, 2007

Mechanical pressing of soybean is highly desirable as it provides, at low cost, non-contaminated, protein-rich, low-fat soyflour which can be further processed into nutritious edible foods. Unfortunately, mechanical pressing of this low-fat oilseed ($<$20%) yields only 50-70% of the available oil, in contrast to the solvent extraction method which recovers over 98% of the oil. The main focus of the study was to maximize the oil recovery from soybean using mechanical oil expression by applying two pretreatments, enzymatic hydrolysis and extrusion cooking of soybeans, and by varying the pressing conditions including three applied pressures (20, 40 and 60 MPa), three pressing temperatures (22, 60 and 90°C) and two sample sizes (10 and 20 g). To characterize the material properties affecting mechanical oil expression from soybean a mathematical simulation of uniaxial compression was developed which incorporated the time dependent variation of soybean properties. The mathematical simulation was based on Terznaghi's theory of consolidation for soils and was solved using measured values of the coefficients of permeability, volume change and consolidation. A compression-permeability test cell was specifically developed for these measurements. For validation of the model, in addition to extruded soy, sunflower seeds (oil content ca. 45%) were also compressed under the same pressing conditions. Improvements in oil recovery due to enzymatic pretreatment of soybean were small, while the extrusion pretreatment increased the oil recovery from only a trace for raw soybean to 90.6%. Such oil recovery using mechanical pressing of soybean has not been reported in the past. The measured values of oil recovery, coefficients of permeability, volume change and consolidation for soybean and sunflower seeds were found to vary significantly $(P<0.05)$ with time of pressing, applied pressure, pressing temperature and the size of the sample. For extruded soy samples, the developed model predicted the values of oil recovery versus pressing time with an average error of 15%, while for sunflower seed samples the average prediction error was 40%. The high error values were attributed to the presence of hulls in the sunflower seed samples, as well as error during measurement of the coefficient of permeability. The coefficient of consolidation was found to have the greatest influence on oil recovery. The incorporation of time dependent material properties in the developed simulation was demonstrated to give more accurate and consistent prediction in trends of oil recovery as compared to using constant material properties. The correlationship developed between the oilseed material properties and the oil recovery obtained from uniaxially compressed oilseeds would help researchers and designers to better evaluate the mechanical oil expression equipment and systems. To the extent that the developed model adequately predicted oil recoveries from both sunflower and soybean oilseeds, the model is expected to be applicable to other oilseeds as well.

In this study, the aim was enzymatic xylooligosaccharide production from cotton and sunflower stalks, two of main agricultural residues in Turkey. In first two parts of the study, alkali extracted xylan from both of the stalks was hydrolyzed by commercial xylanases Veron and Shearzyme. The effect of temperature, pH, enzyme and substrate concentrations were investigated to determine optimum enzymatic hydrolysis conditions of xylan. Sunflower and cotton stalk xylans were hydrolyzed by Shearzyme more efficiently than Veron under the conditions studied. Shearzyme produced different product profiles containing xylobiose (X2), xylotriose (X3), xylotetrose (X4) and xylopentose (X5) from cotton and sunflower stalk xylan. On the other hand, Veron hydrolyzed both xylan types to produce X2, X3, X5, X6 and larger xylooligosaccharides without any change in product profiles. In the third part of the study, home produced xylanase from Bacillus pumilus SB-M13, was also investigated for the production of xylooligosaccharides from both cotton and sunflower stalk xylan. The main products obtained by hydrolysis of both substrates by pure B. pumilus xylanase were X5 and X6, while crude B. pumilus xylanase generated X4 and X5 as the main products. Xylooligosaccharide production from pretreated cotton stalk without alkali extraction of xylan was the final part of the study. Three different pretreatment methods including biomass pretreatment by Phanerochaete chrysosporium fermentation, cellulase pretreatment and hydrothermal pretreatment were investigated to break down complex lignocellulosic structure of cotton stalk to improve the subsequent enzymatic hydrolysis of xylan in pretreated cotton stalk for xylooligosaccharide production. However, xylooligosaccharide was not effectively produced from pretreated cotton stalk. Shearzyme inhibiton was observed after all the pretreatment methods during further hydrolysis of pretreated cotton stalk probably due to production of inhibitory compounds of the enzyme.

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Plant species were assessed for recolonization of a brownfield in Muncie, IN. In a greenhouse study, soil was seeded to perennial ryegrass (Lolium perenne), red clover (Trifolium pratense) and sunflower (Helianthus annuus). Selected pots were amended with leaf compost and mycorrhizal fungi. Soil and plant tissue were analyzed after 30 and 90 days. Ryegrass and compost were studied at the brownfield site. In the greenhouse, red clover was capable of concentrating the greatest quantity of Cd, Cu, Cr, Ni, and Pb in above-ground biomass (all soil treatments combined). Compost + mycorrhizal fungi treatment resulted in highest Cd, Cu, and Zn plant concentrations (all plant treatments combined). Compost resulted in the highest tissue Cr and Ni concentrations. The reported study demonstrates that this brownfield is capable of being revegetated by turf and legume species. Each infertile and/or toxic site must be assessed for revegetation species on a case-by-case basis. / Department of Natural Resources and Environmental Management

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