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<u>Endothia parasitica</u> (Murr.) P. J. & H. E. Anderson (syn: <u>Cryphonectria parasitica</u>(Murr.) Barr), the causal agent of chestnut blight, was able to grow in total aqueous and tannin extracts from blight-susceptible American chestnut as well as in blight-resistant Chinese chestnut bark extracts, from winter and summer bark. Differences in the amount of conidial germination and growth in extracts of the two species were small. The, <u>E. parasitica</u> tannase was more abundant intracellularly than extracellularly. Total tannase activities from cultures in American chestnut aqueous and tannin extracts were greater than in the Chinese chestnut extracts, for both winter and summer bark. The tannase was isolated from the mycelium of E. parasitica and purified 142-fold with a 10% yield by anion exchange chromatography and gel filtration. The estimated molecular weight was 240 kD and the molecule may be a tetramer composed of four subunits with a molecular weight of 58 kD. The pH optimum of the purified tannase was 5.5 and the temperature optimum for activity was 30 C. The enzyme was separated into six bands in the pH range of 4.6 to 5.1 which may represent isoenzymes or post-translational modifications. / Ph. D.

A series of anthropogenic disturbance conditions have altered the vegetation of the southern Appalachians during the past 200-years. The objective of this research was to identify the nature and timing of these vegetation changes in order to better understand the underlying causes. A total of 304 land surveys were collected for a small agricultural watershed from early settlement in 1787 through to the present day. Witness corners recorded tree species, shrubs, stumps, snags and non vegetative markers. Types of witness corners were tallied and tested for shifts in frequency across time periods. Tree species were also classified by silvical characteristics including sprouting capability, shade tolerance, and seed type and these groupings were tested for shifts in frequency across time periods. Landform bias of the witness corners was tested using references contained in the surveys. Results showed significant shifts in white oak (Quercus alba L.), chestnut (Castanea dentate Marsh. Borkh.), chestnut oak (Quercus prinus Wild.), black oak (Quercus velutina Lam.), red oak(Quercus rubra L.), black locust (Robinia pseudoacacia L.), yellow poplar (Liriodendron tulipifera L.), and scarlet oak (Quercus coccinea Muenchh.). The central change was a steady decline in white oak, probably due to the absence of fire and changes in soil properties. Chestnut replaced white oak as the dominant species, but was removed by chestnut blight in the 1930's. Sprouting capability appeared to be the most important silvical characteristic across all species. / Master of Science

The concept of place is extremely important within today's contemporary society. As a result of hyper mobility, many people do not take the time to notice and understand the spaces surrounding them. A sense of place is subtle and fragile, yet can exist in the most humble of environments. In Appalachian, there are countless structures that dot the mountainous landscape symbolizing the sense of place in southwestern Virginia. The Virginia pole barn is important for the sense of place because of its direct tie to the land. Many of these structures were built from the indigenous American chestnut tree and crafted using traditional building techniques. These structures are an important contribution to the vernacular of the Appalachian region, and much of this is due to the material presence of these structures as they give balance and counterpoint to the ridges and valleys. Secondary research focused on theories about the creation of place, the spirit or character of a specific place, the role of symbols in these creations, and the importance of the American chestnut as a material. Primary research concentrated on the people who interact with these pole barns on a regular basis, the structures themselves, and the prevailing landscapes. / Master of Science

La famille des Fagacées regroupe des espèces présentant un intérêt économique, écologique et social non négligeable. Par ailleurs, ces espèces, et plus particulièrement celles du genre Quercus que l’on retrouve dans des milieux extrêmement diversifiés, constituent de bons modèles d’étude de l’adaptation des arbres à leur environnement. Pour comprendre l’architecture génétique des caractères liés à l’adaptation chez le chêne, des cartes génétiques ont été établies essentiellement sur la base de marqueurs moléculaires dominants. Le travail qui a fait l’objet de cette thèse, a consisté à développer une carte génétique de seconde génération à partir des ressources génomiques disponibles chez cette espèce. Dans un premier temps, nous avons recherché des motifs microsatellites (SSR, simple sequence repeats) au sein des séquences exprimées (EST) assemblées sous la forme d’un unigène de 28 000 éléments non redondant. Un jeu de 748 marqueurs a été développé et 255 d’entre eux ont été localisés sur la carte génétique du chêne pédonculé (Q. robur L.) en utilisant une approche dite de « bin mapping ». Leur transférabilité a été testée chez le châtaignier européen (Castanea sativa Mill.) et le hêtre commun (Fagus sylvatica L.), deux espèces phylogénétiquement proche du chêne. Un taux de transférabilité de 28% a été observé pour le hêtre et de 56,6% pour le châtaigner. Une carte génétique a alors été établie pour le châtaigner en utilisant les marqueurs SSR localisés sur la carte du chêne. La comparaison des cartes de liaison du chêne et du châtaignier a mis en évidence une bonne conservation de la macro synténie et de la macro colinéarité entre les deux espèces, ce qui ouvre des perspectives intéressantes pour le transfert d’informations génétiques (QTL par exemple) d’une espèce à l’autre. Cette étude sera prochainement enrichie par la cartographie de marqueurs orthologues dérivés de polymorphismes ponctuels (SNP), ce qui permettra de comprendre l’évolution conjointe des trois espèces majeures de la famille des Fagacées. / The Fagaceae family comprises species of economic, ecological and social importance. In addition, these species and particularly those belonging to the Quercus genus that are present in very diverse ecological niches, constitute good models to study the adaptation of forest trees to their natural environment. To understand the genetic architecture of adaptive traits in oak, genetic linkage maps have been previously established based on dominant markers. In this thesis, we developed a second generation genetic map using the genomic resources that were available in this species. First, we bioinformatically screened an expressed sequence tags catalog assembled into a 28 000 unigene elements, for simple sequence repeats (SSRs). A set of 748 markers was developed and 255 were localized on the pedunculate oak (Q. robur L.) linkage map using a bin mapping approach. Their transferability was tested in the European chestnut (Castanea sativa Mill.) and common beech (Fagus sylvatica L.), two phylogenetically related species to oak. Transferability rates of 28% and 56.6% were observed for beech and chestnut, respectively. A genetic map was then established for chestnut on the basis of orthologous SSRs already mapped in oak. The comparison between both maps clearly showed that the macro-synteny and the macro-colinearity were conserved across genus, opening interesting perspectives in respect to the transfer of genetic information (eg. QTLs, quantitative trait loci) from one species to another. This study will be soon completed by the mapping of orthologous markers derived from single nucleotide polymorphisms (SNPs). This will made it possible to better understand the evolution of the genome of these three major species of the Fagaceae family.

Leung Bo-Shan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 148-159). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.v / List of Abbreviations --- p.vi / List of Tables --- p.viii / List of Figures --- p.ix / Chapter 1 --- Introduction / Chapter 1.1 --- Food colorants --- p.1 / Chapter 1.2 --- Caramel --- p.3 / Chapter 1.2.1 --- Classes of caramel --- p.3 / Chapter 1.2.2 --- Toxicological studies of caramel --- p.5 / Chapter 1.3 --- Castanea mollissima --- p.9 / Chapter 1.4 --- Antioxidants --- p.10 / Chapter 1.4.1 --- Background --- p.10 / Chapter 1.4.2 --- Methods used to evaluate the antioxidative activity --- p.12 / Chapter 1.4.2.1 --- DPPH* scavenging method --- p.13 / Chapter 1.4.2.2 --- High performance liquid chromatography (HPLC) --- p.13 / Chapter 1.5 --- Microtox® test --- p.19 / Chapter 1.6 --- Mutatox® test --- p.19 / Chapter 1.7 --- Methods used to evaluate the functions of major organs --- p.20 / Chapter 1.7.1 --- Liver --- p.20 / Chapter 1.7.2 --- Kidneys --- p.23 / Chapter 1.8 --- Toxicology --- p.25 / Chapter 1.8.1 --- Acute toxicity test --- p.25 / Chapter 1.8.2 --- Chronic toxicity test --- p.26 / Chapter 1.9 --- Objective --- p.27 / Chapter 2 --- Materials and Methods --- p.28 / Chapter 2.1 --- Plant materials --- p.28 / Chapter 2.2 --- Sample preparation --- p.28 / Chapter 2.3 --- Pigment characterization --- p.30 / Chapter 2.3.1 --- Stability test --- p.30 / Chapter 2.3.2 --- HPLC separation of CP --- p.31 / Chapter 2.3.3 --- Determination of antioxidative activity with the DPPH* scavenging method --- p.31 / Chapter 2.4 --- Microtox® test --- p.33 / Chapter 2.5 --- Mutatox® test --- p.34 / Chapter 2.6 --- Acute toxicity test --- p.35 / Chapter 2.6.1 --- Animals --- p.35 / Chapter 2.6.2 --- Housing and maintenance --- p.35 / Chapter 2.6.3 --- Experimental design --- p.37 / Chapter 2.6.4 --- Chemicals --- p.39 / Chapter 2.6.5 --- Clinical pathology test --- p.41 / Chapter 2.6.5.1 --- Haematology --- p.41 / Chapter 2.6.5.2 --- Blood chemistry --- p.45 / Chapter 2.6.5.3 --- Urinalysis --- p.55 / Chapter 2.6.6 --- Histological study --- p.57 / Chapter 2.6.7 --- Statistical analysis --- p.57 / Chapter 2.7 --- Chronic toxicity test --- p.59 / Chapter 2.7.1 --- Animals --- p.59 / Chapter 2.7.2 --- Housing and maintenance --- p.59 / Chapter 2.7.3 --- Experimental design --- p.59 / Chapter 2.7.4 --- Chemicals --- p.60 / Chapter 2.7.5 --- Clinical pathology test --- p.61 / Chapter 2.7.5.1 --- Haematology --- p.61 / Chapter 2.7.5.2 --- Blood chemistry --- p.62 / Chapter 2.7.5.3 --- Urinalysis --- p.62 / Chapter 2.7.6 --- Histological study --- p.62 / Chapter 2.7.7 --- Statistical analysis --- p.62 / Chapter 3 --- Results --- p.63 / Chapter 3.1 --- Pigment characterization --- p.63 / Chapter 3.1.1 --- Stability test --- p.63 / Chapter 3.1.2 --- HPLC separation of CP --- p.63 / Chapter 3.1.3 --- Antioxidative activities of CP preparations --- p.63 / Chapter 3.2 --- Microtox® test --- p.65 / Chapter 3.3 --- Mutatox® test --- p.65 / Chapter 3.4 --- Acute toxicity test --- p.66 / Chapter 3.4.1 --- Growth rate --- p.66 / Chapter 3.4.2 --- Food and fluid consumption --- p.66 / Chapter 3.4.3 --- Organ-weight --- p.66 / Chapter 3.4.4 --- Clinical pathology tests --- p.68 / Chapter 3.4.4.1 --- Haematology --- p.68 / Chapter 3.4.4.2 --- Blood chemistry --- p.70 / Chapter 3.4.4.3 --- Urinalysis --- p.76 / Chapter 3.4.5 --- Histological study --- p.76 / Chapter 3.5 --- Chronic toxicity test --- p.77 / Chapter 3.5.1 --- Growth rate --- p.77 / Chapter 3.5.2 --- Food and fluid consumption --- p.77 / Chapter 3.5.3 --- Organ-weight --- p.77 / Chapter 3.5.4 --- Clinical pathology tests --- p.78 / Chapter 3.5.4.1 --- Haematology --- p.78 / Chapter 3.5.4.2 --- Blood chemistry --- p.80 / Chapter 3.5.4.3 --- Urinalysis --- p.82 / Chapter 3.5.5 --- Histological study --- p.82 / Chapter 4 --- Discussion --- p.137 / Chapter 4.1 --- Pigment characterization --- p.137 / Chapter 4.2 --- Toxicological studies of CP --- p.140 / Chapter 5 --- Conclusion --- p.147 / References --- p.148

Made available in DSpace on 2017-07-21T18:53:06Z (GMT). No. of bitstreams: 1 Fernanda Kubiaki.pdf: 1833486 bytes, checksum: 52af7c310dcf42579df3b3b6a0856799 (MD5) Previous issue date: 2016-02-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The chestnut (Castanea sativa, Mill) has lots of nutrients, including starch that is the main compound and is chemically composed of amylose and amylopectin. The starch is the main storage substance for plants and the main energetic source for humans, providing from 70 to 80% of the required daily calories. It is present in many botanical sources and can be used in various industrial sectors, being an important ingredient for processed foods. It can be used in natura or modified by chemical ways, physical, biological or combined techniques. The modified starch is an alternative under continuous development in order to overcome the limitation for some industrial applications of native starch such as low resistance and high tendency to retrogradation, which makes the starch like native. The objective of this study was the chestnut starch (Castanea sativa, Mill) extraction and to evaluate the modification with HCl in two concentrations (0,1 mol/L e 0,5 mol/L) diluted in alcoholic-acid solutions. The behavior of native and modified starch granules were analyzed by thermoanalytical techniques (TG-DTA and DSC), rheological (RVA), structural (XDR and SEM), and color. Furthermore, physical-chemical analyzes were performed on chestnut flour, like protein, ash, lipids, total dietary fiber, carbohydrates and moisture. The samples presented three major weight losses in the TG-DTA analysis, and showed only on native starch sample a strong oxidative character event. There was an increase in the gelatinisation enthalpy for modified samples if compared to the native one. On the other hand, the viscosity and impasting temperature decreased, this probable happened due to the structural weakening after the modification. The granules modification was observed in the scanning electron microscopy, but in the analysis by x ray diffraction the intensity of the samples had a low variation due to the treatments. In the physical-chemical analysis the chestnut flour presented a high content of fiber and low lipids content. This work by performing the chestnut starch modification allowed the knowledge of granules and noticed a change according to the performed modifications, becoming favorable for food industrial uses (marron glacé and candies), non-food and also as a raw material for futures studies of modified starches. / A castanha portuguesa (Castanea sativa, Mill) possui vários nutrientes, sendo o amido o componente principal quimicamente formado por amilose e amilopectina. O amido é a principal substância de reserva para as plantas e a principal fonte energética para o homem, fornecendo de 70 a 80% das calorias diárias necessárias. Está presente em diversas fontes botânicas e pode ser utilizado em diversos setores industriais, sendo um ingrediente importante para os alimentos processados. Pode ser utilizado in natura ou modificado por vias químicas, físicas, biológicas ou técnicas combinadas. O amido modificado é uma alternativa que está em contínuo desenvolvimento para superar as limitações para algumas aplicações industriais do amido nativo, como a baixa resistência e alta tendência a retrogradação. O objetivo deste trabalho foi realizar a extração do amido de castanha portuguesa (Castanea sativa, Mill) e avaliar a modificação com HCl em duas concentrações (0,1 mol/L e 0,5 mol/L) diluído em soluções ácido-alcoólica. O comportamento dos grânulos de amido nativo e modificados foram analisados por técnicas termoanalíticas (TG-DTA e DSC), reológicas (RVA), estruturais (DRX e MEV), e de cor. Ainda, análises físico-químicas foram realizadas na farinha da castanha, sendo elas proteína, cinzas, lipídios, fibra alimentar total, carboidratos e umidade. As amostras mostraram três principais perdas de massa na análise TG-DTA, e observou-se apenas na amostra de amido nativa um forte evento de caráter oxidativo. Houve um aumento da entalpia de gelatinização para as amostras modificadas se comparadas à amostra nativa. Por outro lado a viscosidade e temperatura de empastamento diminuíram, isso se deu provavelmente pelo enfraquecimento estrutural após a modificação. A modificação dos grânulos foi observada na análise da microscopia eletrônica de varredura, porém, na análise de difração por raios X a intensidade das amostras variou pouco a partir do tratamento. Nas análises físico-químicas a farinha da castanha apresentou um alto teor de fibras e um baixo teor de lipídios. O presente trabalho, a partir da realização da modificação de amido de castanha portuguesa permitiu o conhecimento dos grânulos e evidenciou uma alteração de acordo com as modificações realizadas, tornando-a favorável para o uso industrial alimentar (marrom glacé e doces), papel e também como uma matéria-prima para futuros estudos de amidos modificados.