Typescript. / Thesis (Ph. D.)--University of Hawaii, 1966. / Bibliography: leaves 255-264. / xviii, 264 leaves ill

The following thesis is divided into three chapters. The first describes the isolation and identification of a sphingolipid L from the methanolic skin extract of the British Columbia nudibranch Onchidoris bilamellata. The long chain base has been identified as (E)-l,3-dihydroxy-2-amino-16-methyl-4-octadecene (1̲3) and the fatty acid moiety as palmitic acid (1̲2). This ceramide possesses antibacterial activity towards the microorganisms Bacillus subtilis and Staphylococcus aureus. [formula omitted] The second chapter presents our attempt to synthesize a hypothetical structure of nanaimoal (2̲4), a marine sesquiterpenoid, isolated from the British Columbia nudibranch Acanthadoris nanaimoensis. The proposed route envisaged photolysis of a 2,2,10,10-tetrasubstituted cyclodecanone. This work lend to a study of the solution photochemistry of 2,2,10-trimethyl-cyclodecanone (3̲5). [formula omitted] The last chapter outlines studies directed toward the synthesis of capnellene (5̲1), a tricyclopentanoid obtained by Djerassi and co-workers from the soft coral Capnel laimbricata. Starting with an improved synthesis of the known ketone Δ¹̕̕̕⁵-bicyclo[3.3.0] octen-2-one (1̲3̲8), an acylation method was developed for the preparation of Δ¹̕⁵-3-carboethoxybicyclo-[3.3.0] octen-2-one (1̲6̲0). The procedure is of general utility and has been extended to related ketones. This unsaturated keto-ester underwent a Michael addition with methyl vinyl ketone to give 1̲7̲8. Selective Knoevenagal condensation of the methyl ketone produced Δ¹̕⁵-3-carboethoxy-3-(dimethyl-3-methyl-3-butenyl-4,4-dicarboxylate)-bicyclo[3.3.0] octen-2-one (179). Reduction of the unsaturated ketone and dehydration of the allylic alcohol produced a 1,1,3,4-tetrasubstituted cyclopentadiene derivative 1̲8̲1. Intramolecular Diels-Alder cyclization of the latter afforded the tetracyclic tricarboxylic ester 1̲8̲2. Selective hydrolysis of the malonic estertricarboxylic ester 1̲8̲2 followed by decarboxylation led to 1̲8̲3, a key intermediate for the ultimate construction of the capnellane ring system. [formula omitted] / Science, Faculty of / Chemistry, Department of / Graduate

The two British Columbia nudibranchs Cadiina luteomarginata and Acanthadoris nanaimoensis have sweet fragrances. The possible importance of odours in the interactions of marine organisms initially aroused our chemical curiosity. The results of our research concerning the structural investigation of seven terpenoids obtained from the organic extracts of these two opisthobranch molluscs is presented in this thesis. Five of the molecules isolated from luteomarginata have been identified as furodysin (53), furodysinin (54), microcionin-2 (55), albicanyl acetate (51) and albicanol (52). A sixth molecule, luteone (57) which gives the sweet fragrance to C. luteomarginata has been partially characterized . A crystalline derivative of this methyl ketone has been submitted for X-ray diffraction analysis. The sweet fragrance of A. nanaimoensis has been related to the presence of a sesquiterpenoid (existing as two constitutional isomers, in a 5:1 ratio). Three hypothetical structures based on spectral analysis, chemical reactions and biosynthetic reasoning are proposed. The biological origin of the seven terpenoids has also been investigated and is discussed in this thesis. / Science, Faculty of / Chemistry, Department of / Graduate

Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1983. / Bibliography: leaves 119-125. / Microfiche. / xvii, 125 leaves, bound ill. 29 cm

Typescript. / Bibliography: leaves 219-234. / x, 234 l illus

Thesis (Ph.D.) - University of Queensland, 2004. / Includes bibliography.

In this study particular attention has been paid to the foraging biology and ecology of Aeolidia papillosa (L.); an anemone-eating nudibranch mollusc. 'Prey-value', derived in its current biological sense from optimal foraging models, is expected to be an important determinant of prey-selection behaviour. In the present study 'prey-values', or more specifically, food or tissue-values (because intact anemones were not used in the analyses), have been investigated for a range of anemone species. Analysis of the biochemical composition of anemone tissues and their consumption and assimilation by nudibranchs did not reveal any marked interspecific differences. S.troglodytes, however, is indicated as being somewhat different from the other species studied, possibly being assimilated more efficiently and consumed at a faster rate. These factors, in conjunction with the strong preferences shown for S.troglodytes in switching experiments and the apparent preponderance of field associations with this species, do Indicate that S.troglodytes may be a more valuable food item for A.papillosa. Analysis of the canposite estimates of fitness (growth and reproduction), however, did not reveal any contrasts in performance which could be related to diet. This was almost certainly a result of the marked variability in the performance of nudibranchs within each diet group obscuring any dietary effects which may have obtained. In the latter part of this study a series of behavioural experiments were conducted which investigated specific aspects of prey-selection behaviour. Using a variety of multiple-prey species choice experiments, data have been collected which show the effects of previous dietary experience on prey-species selection. The results of these experiments suggest that at least some of the contradictions in previous reports of prey-species preference by A.papillosa may be accounted for by "ingestive conditioning". "Ingestive conditioning" concerns the modification of a predator's behaviour such that it continues to choose that prey species which it has most recently or most frequently encountered. Such alterations of prey preference may exert considerable effects on the control of local anemone prey populations and their relative abundances. A variant of this experiment was ccmpleted during a five week investigation at the Friday Harbor Marine Laboratories, University of Washington, in the summer of 1982. Experiments showed that ingestive conditioning occurs for both U.K. and N.W Pacific A.papillosa. However, the modified experimental design used in Friday Harbor, and in corroborative experiments in St Andrews, also indicate that there is a significant "carry-over" effect from the previous conditioning diet. In the light of these results it was predicted that A.papillosa might exhibit frequency-dependent (i.e. switching) prey selection. Experiments undertaken to test this hypothesis were unable to demonstrate such behaviour due to persistent preference for one particular prey species. Field observations of A.papillosa-anemone associations are discussed in relation to the laboratory investigations.

Typescript. Includes vita and abstract. Bibliography: Includes bibliographical references. Content: Patterns of development in nudibranch mollusks from the northeast Pacific Ocean, with regional comparisons. -- Lecithotrophic development in Doto amyra (Nudibranchia: dendronotacea), with a review of development in the genus. -- Unusually large polar bodies in an aeolid nudibranch, a novel mechanism for producing extra-embryonic yolk reserves. xiv, 237 leaves : ill. ; 29 cm. / Biogeographic patterns of developmental mode in marine invertebrates have been examined with respect to latitude, depth, and general habitat type. Regional comparisons, which might reveal the influence of specific ecological mechanisms on mode of development, are few. The present study was undertaken to: 1) characterize early development, especially its mode, in nudibranch molluscs from the cold temperate waters of the northeast Pacific Ocean: 2) compare the development of these species to that of nudibranchs from other geographic regions: and 3) attempt to explain the observed patterns on the basis of regional differences in hydrography, geology, and primary production. Observations of egg size, embryonic development and hatching larvae were made for 30 species and were supplemented with data from the literature. All data for other regions were obtained from the literature. Developmental mode was determined for 69 NE Pacific species, over half the known fauna. sixty-seven (97%) have planktotrophic development and two (Doto amyra and the introduced Tenellia adspersa) produce short-term lecithotrophic larvae. No evidence for nurse-eggs was obtained in this study, and only the egg capsules of the aeolid Cuthona lagunae were found to contain extra-zygotic yolk reserves. These took the novel form of unusually large, yolk-filled polar bodies that were ingested by the embryonic veligers. Planktotrophic species with egg-shaped, inflated larval shells develop from larger eggs than those of species with typical spiral shells. The former, however, have shorter embryonic periods, owing, in part, to their smaller egg masses; many also hatch with eyespots. World-wide I conclude that planktotrophy, at least among nudibranchs, is most common in regions with relatively slow currents, high standing stocks of phytoplankton, and large expanses of habitat suitable for the adults. This is documented by evidence from the NE Pacific, NE u.s., Britain, NW Red Sea, and NW Mediterranean. Nonfeeding modes of development tend to predominate in areas with fast boundary currents, oligotrophic waters, rapid changes in physical aspects of the adult environment, or in areas formerly in contact with polar waters (e.g., SE U.S., Marshall Is., New South Wales). Latitude and its correlates do not sufficiently account for the observed regional differences in mode of development.

Graduation date: 1993

ix, 62 leaves : ill. ; 29 cm Notes Typescript Thesis (M.S.)--University of Oregon, 1987 Includes vita and abstract Bibliography: leaves 59-62 Another copy on microfilm is located in Archives