Thesis (Ph. D.)--Harvard University, 1991. / Includes bibliographical references (leaves 269-278).

Thesis (Ph. D.)--Oregon State University, 2011. / Printout. Includes bibliographical references (leaves 130-135). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 108-131).

The proteolytic enzymes in the muscle fluid of Pacific whiting (Merluccius productus) were studied and compared to those found in muscle fluid of true cod (Gadus macrocephalus). Preliminary studies indicated three pH optima of activity for whiting, pH 3.5-3.9, 4.3-4.6 and 7.1-7.2. Only two pH optima were found for the proteolytic activity of true cod, pH 3.2-3.6 and 7.7-8.0. The sarcoplasmic fluid of whiting and cod muscle was studied in more detail. For both whiting and cod, no hydrolysis of the substrates hippuryl-L-phenylalanine, hippuryl-L-arginine, α-N-benzoyl-D,L-arginine p-nitroanilide (BAPA), or toluene sulfonyl arginine methyl ester (TAMA) at neutral pH's could be detected, indicating the absence of trypsin and carboxypeptidases A and B. Neither whiting nor cod contained elastase and only whiting was shown to have activity similar to that of cathepsin B. True cod was found to contain higher chymotrypsin activity than whiting at pH 7.15 using the substrate glutaryl-L-phenylalanine p-nitroanilide. Hydrolysis of the substrate glutaryl-L-phenylalanine β-naphthylamide (Gly-Phe-2-naphthylamide) from pH 5 to 8 occurred to a greater extent in Pacific whiting than in true cod. Various inhibitors and activators were used to characterize the enzymes in whiting and cod muscle hydrolyzing the substrates GPNA and Gly-Phe-2-naphthylamide. The responses to the chemicals were compared with the effects reported in the literature on the hydrolysis of the substrates by enzymes found in other animal sources. / Graduation date: 1981

The optimum conditions for the proteolytic solubilization of trash fish and processing carcass waste in a simple shell-in-tube heat exchange system was investigated. The nutritional and chemical effects of processing variables were evaluated. An exogenous source of proteolytic enzymes (albacore tuna viscera, Thunnus alalunga) yielded a linear increase in the rate of the proteolytic hydrolysis of ground whole Pacific hake (Merluccius productus) up to 40% in the reaction mixture at 55°C. At 60°C optimum temperature for proteolytic hydrolysis was established with a 20% viscera 80% hake reaction mixture. Acidification of hake with 85% H₃PO₄ greatly accelerated proteolytic hydrolysis yielding an optimum between pH 3.6 and 3.7. The optimum pH for liquification based upon the viscometric properties of reaction mixtures varied from that for hydrolysis and was between 4.3 and 5.1. The chemical characteristics of the proteolytic solubilization of hake at 55°C was determined. The total nitrogen and free amino and tyrosine equivalent content of trichloroacetic acid (TCA), water and sodium dodecylsulfate (SDS) fractions of reactions containing 0, 2 and 4% 85% H₃PO₄ were determined at various times over a two hr period. With accelerated reactions (2 and 4% 85% H₃PO₄) the rate of hydrolysis was greatly reduced after 30 min. Under less than optimum pH conditions (0% 85% H₃PO₄) proteolytic hydrolysis proceeded in a linear fashion throughout the two hr period. The relationship between the quantities of chemical indices in the TCA and water fractions suggested that the majority of the proteolytic action yielded amino acids and short peptides. The total nitrogen content of the SDS soluble fraction inferred that very little of the protein that was not SDS soluble was being solubilized. The protein efficiency ratio of samples of hake reacted at 55°C in the presence of 0, 2 and 4% (wt/wt) 85% H₃PO₄ at 30, 60, and 120 min was determined to assess the nutritional effects of proteolytic solubilization. Proteolytic action reduced protein quality to a degree related directly to the level of acid accelerated proteolytic action. Full reduction in quality was accomplished at the end of 30 min for reaction mixtures containing 0 and 2% acid in comparison to a raw hake control; no reduction was observed between 30 and 120 min. In addition to the initial reduction in quality within the first 30 min of reaction, mixtures containing 4% acid were significantly reduced between 30 and 120 min. Conversion of native protein to nutritionally less utilizable amino acids and peptides probably played the major role in reducing protein quality in reaction mixtures containing 0 and 2% acid. The time dependent reduction in protein quality for the reactions containing 4% supports the destruction of amino acids, probably tryptophan, at this higher level of acidity. / Graduation date: 1977

Graduation date: 1974

Thesis (Ph. D.)--University of Hawaii at Manoa, 2001. / Includes bibliographical references (leaves 333-342). Also available by subscription via World Wide Web.

In 1986 the remains of a shipwreck were discovered on Sand Island in the mouth of the Columbia River in the Pacific Northwest. The following year, a team of archaeologists investigated the site in order to determine its original identity. After a series of dives, the team concluded that the wreck was the remains of the Hudson’s Bay Company brig, Isabella, a ship that was lost in that area in 1830. Recent investigations on the shipwreck disproved this identity. The turbulent conditions of the Columbia River have helped researchers by shifting a significant amount of sand overburden away from the vessel, exposing a greater area of the ship. With this new information, the wreck is now believed to be the remains of the wooden side-wheel steamer Great Republic that belonged to the Pacific Mail Steamship Company, rather than Isabella. This thesis investigates the history of Great Republic and its role in American maritime history, as well as its possible archaeological remains at the bottom of the Columbia River. In order to provide a clear and concise story, I begin with the history of the Pacific Mail Steamship Company and its importance in the development of the western coast of the United States. Since Great Republic was integral to the Asian trade of the nineteenth century, the second portion of the thesis is dedicated to Asian-American commercial and political relations during the nineteenth century. Great Republic and its three sister ships are then described and analyzed in detail based on contemporary sources. Finally, the archaeological evidence is assessed beginning with the discovery of the wreck. I detail the investigations and discoveries made on the wreck over the last 20 years. In my conclusions I discuss the importance of Great Republic from a historical standpoint and emphasize its place in American maritime history. I also detail key aspects concerning the wreck that I believe are imperative for future research. Though the remains convincingly appear to be those of Great Republic there are still structural features that need to be analyzed before a positive identification is possible.

In 1986 the remains of a shipwreck were discovered on Sand Island in the mouth of the Columbia River in the Pacific Northwest. The following year, a team of archaeologists investigated the site in order to determine its original identity. After a series of dives, the team concluded that the wreck was the remains of the Hudson’s Bay Company brig, Isabella, a ship that was lost in that area in 1830. Recent investigations on the shipwreck disproved this identity. The turbulent conditions of the Columbia River have helped researchers by shifting a significant amount of sand overburden away from the vessel, exposing a greater area of the ship. With this new information, the wreck is now believed to be the remains of the wooden side-wheel steamer Great Republic that belonged to the Pacific Mail Steamship Company, rather than Isabella. This thesis investigates the history of Great Republic and its role in American maritime history, as well as its possible archaeological remains at the bottom of the Columbia River. In order to provide a clear and concise story, I begin with the history of the Pacific Mail Steamship Company and its importance in the development of the western coast of the United States. Since Great Republic was integral to the Asian trade of the nineteenth century, the second portion of the thesis is dedicated to Asian-American commercial and political relations during the nineteenth century. Great Republic and its three sister ships are then described and analyzed in detail based on contemporary sources. Finally, the archaeological evidence is assessed beginning with the discovery of the wreck. I detail the investigations and discoveries made on the wreck over the last 20 years. In my conclusions I discuss the importance of Great Republic from a historical standpoint and emphasize its place in American maritime history. I also detail key aspects concerning the wreck that I believe are imperative for future research. Though the remains convincingly appear to be those of Great Republic there are still structural features that need to be analyzed before a positive identification is possible.

Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (p. 113-127).