Copy of author's previously published article inserted. Bibliography: leaves 180-195. Investigation of the contribution of polyphenol oxidase (PPO) and peroxidase (POD) to enzymic browning in sugarcane juice.

Angiogenesis is one of the essential hallmarks of cancer, typically breast cancer. Signaling from VEGFR-2 is necessary for the execution of VEGF-induced proliferation, migration, and tube formation of cultured endothelial cells in vitro and the onset of angiogenesis on tumors in vivo. Ellagic acid is a naturally existing small molecular polyphenol widely found in fruits and vegetables. It was reported that ellagic aicd interfered with some angiogenesis-dependent pathologies. Yet the mechanisms involved were not fully understood. Thus we analyzed its anti-angiogenesis effects and mechanisms on human breast cancer utilizing in vitro and in vivo methodologies. Besides, the in silico analysis was carried out to further analyze the structure-based interaction between ellagic aicd and VEGFR-2. The influences of ellagic aicd on VEGF-induced endothelial cells were studied by proliferation, tube formation and migration in vitro experiments. Kinase activity assay and western blotting were utilized to explore the effects of ellagic aicd on VEGFR-2 induced signaling pathway. Organ-based chick aortic ring model, in vivo Chorioallantoic membrane model and in vivo breast cancer xenografts were built to determine the anti-angiogenesis effects of ellagic aicd. Besides, software LigandFit algorithm in Discovery Studio 2.1 (Accelrys Inc., San Diego, CA) was applied to further understand the structure-based interaction between ellagic aicd and VEGFR-2. We found that ellagic aicd impeded a series of VEGF-induced angiogenesis processes including proliferation, migration and tube formation of endothelial cells. Besides, it directly inhibited VEGFR-2 tyrosine kinase activity and its downstream signaling pathways including MAPK and PI3K/Akt on endothelial cells. Ellagic aicd also obviously inhibited sprouts formation from chicken aorta and neo-vessel formation in chick chorioallantoic membrane. The growth and the P-VEGFR2 expression in breast tumors treated with ellagic aicd were also significantly suppressed. In the molecular docking simulation experiment, the structure-based interaction of VEGFR-2 with ellagic acid was found to be stable conformation by hydrogen bonds within residues Lys866 and Glu883 as well as by π–π interactions within residue Phe1045 at ATP binding pocket of VEGFR-2 catalytic domain. Taken together, ellagic aicd could exert anti-angiogenesis effects via VEGFR-2 signaling pathway in breast cancer. / published_or_final_version / Chinese Medicine / Master / Master of Philosophy

The influence of cultivar and maturity on polyphenolic composition and antioxidant activity was investigated by UV-Visible spectrophotometry and analytical high performance liquid chromatography (HPLC) in commercially important blackberry cultivars and selections. The anthocyanin pigments changed tremendously with ripening. Total anthocyanins increased from 74.7-317 mg/100g fw from underripe to over ripe for 'Marion', and from 69.9-164 mg/100g fw for 'Evergreen'. Total phenolics did not show marked change with maturity with values slightly decreasing from underripe to ripe. Antioxidant activities, while increasing with ripening, did not show the noticeable change that total anthocyanins exhibited. The total phenolic and total anthocyanin contents varied greatly among 11 cultivars. Total anthocyanins ranged from 131-256 mg/100g fw (mean = 198), total phenolics from 682-1056 mg GAE/100g fw (mean = 900), ORAC from 37.6-75.5 μmolTE/g fw (mean = 50.2), and FRAP ranged from 63.5- 91.5 μmolTE/g fw (mean = 77.5). Four blackberry cultivars were found to be higher in total anthocyanins and total phenolics than 'Marion' and 'Evergreen', the predominant commercial cultivars in the Pacific Northwest. The results from these studies confirmed that blackberries are a good source of natural antioxidants and colorant, and demonstrated the potential for obtaining new cultivars with high pigment/phenolic content through classical plant breeding. The investigation on the incidence of haze and sediment formation revealed that the sediment in the commercial reconstituted 'Evergreen' blackberry (CRE) juice was composed of ellagic acid, protein, and unidentified compounds. The qualitative tannin and protein-tannin haze test indicated that the sediment was predominantly tannin or protein-tannin complexes. Nitrogen determination showed the sediment to be 6.69 ± 2.21% (w/w) protein on a dry weight basis. Almost all of the extractable material was identified as ellagic acid by HPLC and LC-MS. The ellagic acid content of the wet sediment was 0.05 g/100g while it was 7.41 g/100g in freeze-dried sediment. Tannase enzyme did not significantly decrease the concentration of ellagitannins in 'Marion' blackberry juice in this study. / Graduation date: 2004

Copy of author's previously published article inserted. / Bibliography: leaves 180-195. / xii, 195 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Investigation of the contribution of polyphenol oxidase (PPO) and peroxidase (POD) to enzymic browning in sugarcane juice. / Thesis (Ph.D.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 1995

Thesis (Ph. D.)--Rutgers University, 2010. / "Graduate Program in Food Science." Includes bibliographical references (p. 130-152).

Thesis (M.S.)--University of Texas at El Paso, 2009. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.

Thesis (Ph. D.)--University of Hong Kong, 2000. / Includes bibliographical references (leaves 263-290).

Thesis (Ph. D.)--Rutgers University, 2007. / "Graduate Program in Nutritional Sciences." Includes bibliographical references (p. 104-127).

Dicaffeoylquinic acid (DCQA) is a natural polyphenolic compound widely distributed in plants such as coffee beans, which possesses a range of pharmacological activities. Herein, is reported studies undertaken towards the first total synthesis of 3,5-DCQA conjugates. Two synthetic routes were investigated. The first route involves a seven step sequence beginning from quinic acid. The overall yield via this synthetic approach was 30%. The key steps involved in the sequence were a regioselective benzylation of the C-3-hydroxyl group followed by silyl protection of the C-1 and C-4 hydroxyl groups. Deprotection of the benzyl group by hydrogenolysis and opening of the lactone afforded the 3,5-diol. Esterification of the 3,5-diol with 3,4-tert-butyldimethylsilyl caffeoyl chloride afforded the di-ester. Removal of the protecting groups afforded 3,5-DCQA. The second route involved selective protection of the C-3-hydroxyl group with silyl followed by benzylation of the C-1 and C-3 hydroxyl groups. Saponification of the lactone ring followed by benzylation of the carboxylic acid gave the benzyl ester. Silyl deprotection afforded the 3,5-diol. The 3,5-diol was subsequently esterified by refluxing in toluene with commercially available Meldrum’s acid. In the final step, the synthesis of 3,5-DCQA was achieved by a Knoevenagel condensation of 3,4-dihydroxybenzaldehyde and a malonate ester of quinic acid. An efficient method for the synthesis of possible metabolites of quinic acid conjugates was also described. This protocol employs N-(4-methoxyphenyl)-trifluoroacetimidate glucuronyl as the donor. The key reaction in this sequence was the coupling of N-(4-methoxyphenyl)-trifluoroacetimidate glucuronyl with 4-hydroxy-3-methoxy-benzaldehyde.

published_or_final_version / Physics / Doctoral / Doctor of Philosophy