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No description available.

Sediment was fertilized with f/2 algal growth medium in situ and in the laboratory daily for one week. Sampling strategy incorporated two intertidal heights and two sites. Experiments were done in August and January. No significant changes in chlorophyll a or diatom community structure were observed after ten days of growth in either the field or the laboratory experiments. Laboratory experiments also showed slightly increased gross primary production (p<.10) and increased oxygen uptake (p<.01) associated with nutrient enrichment. Unlike planktonic diatoms, sediment-associated diatoms in Yaquina Bay show no nutrient limitation. Thus other factors probably control diatom growth in these sediments such as light intensity, photoperiod, intertidal height, sediment stability and organic content, and animal consumption. / Graduation date: 1982

Investigation was made into the influence of changing light intensity on the organic and elemental composition of two species of marine diatoms, Ditylum brightwellii and Skeletonema costatum. Analysis was made of the relative changes in soluble and insoluble carbohydrate; polar, non-polar, and total lipid; amino acids; proteins; and total carbon, hydrogen, nitrogen, and oxygen. Photosynthetic quotients were calculated from both organic and elemental composition. The response of soluble and insoluble carbohydrate was directly related to light intensity, although differences were noted between the two fractions. In general, amino acids and proteins showed little or no response to light intensity. Polar (pigment) lipids usually varied inversely with light intensity, whereas non-polar lipids varied directly with intensity. Total lipids also varied inversely with intensity although, considering the total amount of lipid present, the changes were slight. Some differences in relative organic composition were noted between the two species. On the basis of the data, average organic composition of each species was computed and compared with similar data in the literature. The effect of light intensity on the elemental composition of the two species yielded some differences, which were more readily apparent in the photosynthetic quotients calculated from elemental data. The photosynthetic quotient varied inversely with light intensity. Conclusions are summarized and suggestions for future research included. / Graduation date: 1970

Ph.D. in Marine Environmental Science. Includes bibliographical references (p. 137-155).

Biomass production of chlorophyllase of the marine alga (Phaeodactylum tricornutum) at the exponential and stationary stages was performed. The results demonstrated that the biomass yield at the stationary stage was three times that of the exponential stage. A procedure for the extraction and purification of chlorophylls from fresh spinach leaves, used as substrate, was also developed. Chlorophyllase was extracted from photosynthetic membranes of the disrupted cells and partially purified. The purification procedure resulted into 70-fold increase in enzyme activity. Further purification of the partially purified enzyme was performed, using preparative isoelectric focusing on Rotofor-Cell System. Three enzyme fractions, FI$ sp prime$, FII$ sp prime$, and FIII$ sp prime$ were separated, however, most of enzyme activity (84%) was located in fraction FII$ sp prime$. The partially purified chlorophyllase was further purified by native preparative gel electrophoresis on Prep-Cell System, which resulted into a single active fraction. The purified enzyme fraction was then subjected to further purification, using automated Fast Protein Liquid Chromatography (FPLC) System, on ion-exchange Mono Q HR 5/5 column. The purification procedure resulted into two well separated isozymes, FI$ sp prime$ and FII$ sp prime$. Enzyme fraction (FI$ sp prime$) showed the highest enzymatic activity compared to FII$ sp prime$. The homogeneity of each fraction was demonstrated by a single protein band on SDS-PAGE. The molecular weights of these fractions FI$ sp prime$ and FII$ sp prime$ were 67 kD and 66kD, respectively. The optimum pH for chlorophyllase activity fractions FI$ sp prime$, and FII$ sp prime$ were 8.0 and 8.3, respectively. The enzymatic fraction FI$ sp prime$ showed higher activity towards commercial purified chlorophyll b when it was compared to that with the crude chlorophyll, partially purified chlorophyll and commercial purified chlorophyll a. However, enzymatic fraction FI

Thesis (M.S.)--Wisconsin State University (La Crosse), 1969. / Includes bibliographical references (leaf [18]).

Thesis (Ph. D.)--Lehigh University, 1998. / Includes vita. Bibliography: leaves 98-109.

Thesis (Ph. D.)--California Institute of Technology, 1957. / Includes bibliographical references (leaves 175-181).

Thesis (Ph.D.)--Drexel University, 2009. / Includes abstract and vita. Includes bibliographical references (leaves 85-94).