Thesis (M.S.)--Rutgers University, 2008. / "Graduate Program in Animal Sciences." Includes bibliographical references (p. 48-51).

Thesis (M.Med.Sc.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 44-57). Also available in print.

Thesis (M.S.)--Brock University, 2005. / Includes bibliographical references (leaves 170-213). Also available online (PDF file) by a subscription to the set or by purchasing the individual file.

Thesis (M.S.)--The University of North Carolina at Greensboro, 2010. / Directed by Michael McIntosh; submitted to the Dept. of Nutrition. Title from PDF t.p. (viewed Jul. 14, 2010). Includes bibliographical references (p. 42-50).

Thesis (M. Sc.)--Brock University, 2005. / Includes bibliographical references (leaves 170-213)

The enzyme polyphenolase, which catalyses the oxidation of phenols to catechols and subsequently dehydrogenates these to o-quinones, is widely distributed in nature. The multicopy plasmid vector pIJ702 contains a mel gene from Streptomyces antibioticus, that codes for the production of a polyphenol oxidase. The plasmid was isolated from Streptomyces lividans 66pIJ702 and subjected to a variety of mutagenic treatments in order to establish a structurefunction relationship for the polyphenolase enzymes. An attempt was made to engineer the polyphenolase enzyme by localized random mutagenesis in vitro of the mel gene on pIJ702, in order to alter properties like productivity, activity and substrate specificity. It was hoped to alter the amino acid sequence of the active site of the enzyme in order to facilitate catalysis in an organic environment. The plasmid was subsequently transformed into a plasmid-free Streptomyces strain, and enzyme production was carried out in batch culture systems, in order to determine the effect of the height treatment, and to isolate and propagate functional polyphenolase mutants for organic synthesis.

No description available.

No description available.

Unambiguous structure assignment of standards is essential for metabolome characterization of infected plants. Complete structure elucidation of eleven natural polyphenols, resveratrol (1), (-)-epicatechin (2), pelargonidin chloride (3), cyanidin chloride (4), cyanin chloride (5), keracyanin chloride (6), caftaric acid (7), quinic acid (8), procyanidin B1 (9), procyanidin B2 (10), and procyanidin C1 (11) by 1H-, 13C, COSY-, TOCSY-, ROESY-, and HMBC-NMR is described. The sinusoidal modulation frequency of 1H-13C-cross-peaks (J-HMBC) was fitted iteratively to sin(πJH,Ctvar) and yielded 2,3J-coupling values for 1H-13C-correlations in the natural polyphenols. Satisfactory fit to standard Karplus-equations was achieved for glycosides directly attached to the aromatic core in cyanin chloride. Molecular dynamics simulation data in vacuum at the AM1-level of theory were shown to approximate the NMR-solution data reasonably well. Analysis of these standards enables the characterization of unknown plant metabolites produced by bacterially stressed Thompson grape plants provided by the USDA. Initial steps for structure elucidation of 72 unknown fractions is discussed. In addition, selective HCl-catalyzed H/D-exchange was observed for aromatic protons H6 and H8 in flavonoid structures containing a 5,7-meta-disubstituted chromelynium core with free OH-groups. The exchange took place readily in compounds 3, 4, and 6, whereas 1, 2, and 5 did not exchange.

Thesis (M.S.)--Miami University, Dept. of Chemistry and Biochemistry, 2004. / Title from first page of PDF document. Includes bibliographical references (p. 61-63).