The projects described in this dissertation concentrated on investigating Caribbean species for qualitative and quantitative chemical differences. Chapter one includes a brief update on the status of natural products as drugs, a discussion of the biodiversity of Caribbean marine organisms as well as a discussion about the chemistry of algae and sponges. In chapter two, an experiment to test for possible effects of warmer, more acidic water and how that will impact coral reef organisms was conducted. Six common Caribbean coral reef sponge species were grown in seawater for 24 days ranging from values experienced at summer-maxima (temperature = 28 ºC; pH = 8.1) to those predicted for the year 2100 (T = 31 ºC; pH = 7.8). For each species, attachment rates, growth, and survival were similar between temperature and pH levels. Only two metabolite concentrations varied significantly between treatments but were similar to baseline levels. In chapter three, a chemical survey of Florida Keys algae was performed using MeOH extraction and HP-20 SPE with varying Me2CO:H2O solutions. 1H NMR spectra were collected for each fraction and analyzed for interesting signals. A Laurencia sp. was extracted and found to contain the known compound isodactylyne (61) with the structure determined using spectroscopic analyses. In chapter four, a Laurencia obtusa specimen was investigated to determine the compound causing oxygenated signals between 4.50 – 4.80 ppm in the 1H NMR spectra observed in chapter three. A large scale extraction and fractionation was performed and the compound was determined to be 1-O-palmitoyl-2-O-myristoyl-3-O-(6-sulfo-α- D-quinovo-pyranosyl)-glycerol (63). In chapter five, the isolation and structural elucidation of a new compound, furocaespitanenone (64) and two known compounds (10R)- and (10S)-10-O-methylfurocaespitanelactol 65 and 66, from a Laurencia sp. collected off of the Florida Keys using MeOH extraction and HP-20 column chromatography is described. A potential biosynthesis of 64 from furocaepsitane (68) is proposed. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2019. / FAU Electronic Theses and Dissertations Collection

Investigates several hypotheses regarding the use of bioflocculation as a harvesting method for wastewater pond microalgae. Research performed on pilot-scale high rate ponds (HRPs) on the California Central Coast.

Orientador: Orlando Necchi Junior / Banca: Luis Henrique Branco / Banca: Valéria Cassano / Resumo: As três seções do gênero Batrachospermum - Acarposporophytum (com uma única espécie, B. brasiliense Necchi), Aristata (B. beraense Kumano, B. cayennense Montagne, B. longiarticulatum Necchi e B. turgidum Kumano) e Macrospora (B. equisetifolium Montagne, B. hypogynum Kumano & Ratnasabapathy e B. macrosporum Montagne) têm sido demonstradas como monofiléticas em estudos filogenéticos envolvendo pelo menos um representante de cada seção. As seguintes hipóteses foram testadas: 1) as seções Acarposporophytum, Aristata e Macrospora constituem grupos monofiléticos dentro do gênero Batrachospermum; as seções têm sido demonstradas como monofiléticas em estudos filogenéticos e com a adição de maior número de espécies e populações essa tendência deverá ser confirmada; 2) A maioria das espécies atualmente reconhecidas em cada seção com base em caracteres morfológicos será corroborada pelos dados moleculares. A presente revisão das três seções teve como objetivos: 1) inferir as relações filogenéticas, bem como os limites de variação intraespecíficas, das espécies dentro e entre as seções, bem como com outras seções do gênero, foram utilizados os caracteres morfológicos diagnósticos atualmente aceitos e três marcadores moleculares - rbcL, gene plastidial que codifica a subunidade grande da RUBISCO; região de "barcode" do gene mitocondrial cox1, que codifica a subunidade 1 da enzima citocromo c oxidase; e UPA - gene plastidial "universal plastid amplicon"; 2) elaborar estudo de revisão para as três seções por meio da realização dos caracteres taxonômicos diagnósticos para espécies desses grupos, à luz dos novos dados moleculares. Foram analisadas 19 amostras provenientes das regiões sudeste, centro-oeste, norte e nordeste do Brasil, além dos espécimes-tipo de cada seção e sequências disponíveis no "GenBank" para cada um dos marcadores utilizados. Os caracteres diagnósticos para o... / Abstract: he three sections of the genus Batrachospermum - Acarposporophytum (with the single species B. brasiliense Necchi), Aristata (B. beraense Kumano, B. cayennense Montagne, B. longiarticulatum Necchi and B. turgidum Kumano) and Macrospora (B. equisetifolium Montagne, B. hypogynum Kumano & Ratnasabapathy and B. macrosporum Montagne) - have been shown to be monophyletic in phylogenetic studies involving at least one member of each section. The following hypotheses were tested: 1) the sections Acarposporophytum, Aristata and Macrospora represent monophyletic groups within the genus Batrachospermum; the sections have been shown to be monophyletic and closely related in previous studies and with the addition of more species and populations this trend will be confirmed; 2) most species currently recognized in each section on the basis of morphological characters will be corroborated by molecular data. This revision of the three sections has the following aims: 1) to infere phylogenetic relationships and the intra-specific limits of variation of the species within and between sections, as well as with the other sections of the genus; the investigation used the morphological diagnostic characters currently applied and three molecular markers - rbcL, the plastidial gene encoding the large sub-unit of RUBISCO; the barcode region of the mithocondrial gene cox1, encoding sub-unit 1 of cythochorme c oxidase; and UPA, plastidial universal plastid amplicon; 2) to carry out a revisional study of the three sections by means of the reevaluation of taxonomic diagnostic characters for species within these groups, in the light of new molecular data. Nineteen new samples were analysed from the southeast, mid-west, north and northeast regions of Brazil, as well as the type specimens of each species and the sequences available in GenBank for each molecular marker. The diagnostic characters for section circumscription and species identification within the sections... / Mestre

Orientador: Orlando Necchi Junior / Banca: Valéria Cassano / Banca: Celia Leite Sant'anna / Banca: Ciro Cesar Zanini Branco / Banca: Antonio Fernando Monteiro Camargo / Resumo: A ordem Charales da classe Charophyceae inclui seis gêneros (Chara Linnaeus, Lamprothamnium J. Grove, Lychnothamnus (Ruprecht) Leonhardi, Nitella C. Agardh, Nitellopsis Hy e Tolypella A. Braun) classificados numa única família (Characeae). O sistema de classificação mais amplamente utilizado foi proposto por Wood & Imahori, é baseado em exclusivamente em caracteres morfológicos e considera que as Characeae formam um contínuo de espécies. As 400 espécies do grupo foram reduzidas a 81 com muitas variedades e formas. Muitos autores apontaram inconsistências no sistema de Wood & Imahori e sugeriram estudos com novas ferramentas (especialmente ultraestruturais e moleculares). No Brasil, foram reportados os gêneros Chara e Nitella, com abordagens essencialmente florísticas. Este trabalho teve por objetivo aplicar marcadores moleculares (sequências dos genes plastidiais que codificam a subunidade grande da enzima ribulose 1-5 bifosfato carboxilase/oxigenase, rbcL - o gene que codifica a enzima maturase K, matK; e os espaçadores nucleares 1 e 2 dos transcritos internos do DNA ribossômico, ITS1 e ITS2), bem como morfologia estrutural (todos caracteres morfológicos considerados diagnósticos) e ultraestrutural (microscopia eletrônica de varredura da ornamentação da parede dos oósporos), para: 1) caracterizar as espécies de Chara e Nitella com ênfase nas regiões Centro-Oeste e Sudeste do Brasil; 2) inferir relações filogenéticas entre as espécies brasileiras de Chara e Nitella com as de ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The order Charales of the class Charophyceae includes six genera (Chara Linnaeus, Lamprothamnium J. Grove, Lychnothamnus (Ruprecht) Leonhardi, Nitella C. Agardh, Nitellopsis Hy and Tolypella A. Braun) classified in a single family (Characeae). The most widely used classification system, proposed by Wood and Imahori, is based exclusively on morphological characters and considers that within Characeae there is a continuum of species. The 400 species of the group were reduced to 81 with many varieties and forms. Many authors pointed out inconsistencies in this system and suggested studies applying new tools (especially ultrastructural and molecular). In Brazil, only the genera Chara and Nitella were reported, mostly in floristic studies. The aim of this investigation was to apply molecular markers (sequences of the plastid genes coding for the large subunit of the ribulose 1-5 biphosphate carboxylase/oxygenase enzyme, rbcL - and the maturase K enzyme coding gene, matK; internal transcriber spacer of nuclar ribosomal DNA, ITS1 and ITS2), as well as morphological (all diagnostic characters currently used) and ultrastructural (scanning electron microscopy of oospore wall ornamentation), to: 1) characterize the Chara and Nitella species with emphasis in the Midwest and Southeast regions of Brazil; 2) to infer phylogenetic relationships between the Brazilian species of Chara and Nitella with those from other regions of the globe; and 3) to associate morphological, ultrastructural oos... (Complete abstract click electronic access below) / Doutor

Algae-derived biodiesel is currently under investigation as a suitable alternative to traditional fossil-fuels. Though it possesses many favorable characteristics, algae remains prohibitively expensive to mass produce and distribute. The most economical means of growing algae are large-scale open pond raceways. These, however, suffer from low culture densities; this fact impacts the cost directly through diminished productivity, as well as indirectly by raising costs due to the necessity of dewatering low culture density raceway effluent. Algae, as a photosynthetic organism, achieves higher culture densities when sufficient light is provided. In open ponds this can be accomplished by frequently cycling algae to the raceway surface. The current work examined delta wing vortex generators as a means of instigating this cycling motion. In particular the impact of spacing and angle of attack was analyzed. These vortex generators were found to significantly increase vertical mixing when placed in a series, developing precisely the motion desired. Their impact on power requirements was also examined. Specifically it was shown that increases in spacing and decreases in angle of attack result in lower power consumption. It was demonstrated that the most efficient mixing generation is achieved by larger spacings and smaller angles of attack. The impact that these devices had on raceway turbulence as measured by dissipation rate was also investigated and compared to published values for algae growth. Raceways were found to be significantly more turbulent than standard algae environments, and adding delta wings increased these levels further.

With world crude oil reserves decreasing and energy prices continually increasing, interest in developing renewable alternatives to petroleum-based liquid fuels has increased. An alternative that has received consideration is the growth and harvest of microalgae for the production of biodiesel via extraction of the microalgal oil or lipids. However, costs related to the growth, harvesting and dewatering, and processing of algal biomass have limited commercial scale production of algal biodiesel. Coupling wastewater remediation to microalgal growth can lower costs associated with large scale growth of microalgae. Microalgae are capable of assimilating inorganic nitrogen and phosphorous from wastewater into the biomass. By harvesting the microalgal biomass these nutrients can be removed, thus remediating the wastewater. Standard methods of oil extraction require drying the harvested biomass, adding significant energetic cost to processing the algal biomass. Extracting algal lipids from wet microalgal biomass using traditional methods leads to drastic reductions in extraction efficiency, driving up processing costs. A wet lipid extraction procedure was developed that was capable of extracting 79% of the transesterifiable lipids from wet algal biomass (16% solids) without the use of organic solvents while using relatively mild conditions (90 °C and ambient pressures). Ultimately 77% of the extracted lipids were collected for biodiesel production. Furthermore, the procedure was capable of precipitating chlorophyll, allowing for the collection of algal lipids independently of chlorophyll. The capability of this procedure to extract lipids from wet algal biomass, to reduce chlorophyll contamination of the algal oil, and to generate feedstock material for the production of additional bio-products provides the basis for reducing scale-up costs associated with the production of algal biofuels and bioproducts.

The continued increase in the demand for fossil fuels combined with their ever dwindling supply has prompted the search for a suitable alternative fuel. The research contained within this dissertation seeks to increase the lipid content of cellular feedstocks, improve extraction efficiencies of lipids, and understand the pathways involved in the production of fatty alcohols and triacylglycerides from microbial feedstocks. As part of this research the diatom, Cheatoceros gracilis, was grown at small and large scale to determine optimal growing conditions. No apparent nutrient stress trigger was required to initiate the accumulation of the biodiesel precursor triacylglyceride, unlike other documented algal strains. A follow-up to this project demonstrated that the microalga C. gracilis may utilize light intensity as a trigger for lipid production. A major difficulty in the production of biofuels from microorganisms is the expensive process of dewatering, drying, and extracting the lipid compounds from the cells. As part of this research, a process has been developed that allows for lipid extraction to occur in the presence of water at a point as low as 2 percent solids or 98 percent water. This process utilizes a single organic solvent that mixes well with microbial lipids, but poorly with water allowing for efficient extraction of lipids and fast solvent to water separation. This process greatly decreases the cost of the microbial biofuels production associated with the removal of water from cell slurries. Triacylglycerides and fatty alcohols are oleochemicals that are commonly used in industrial, pharmaceutical, and consumable processes. A predicted fatty acyl CoA reductase enzyme was cloned into an E. coli vector, expressed, characterized and shown to be active as a dual reductive enzyme reducing a fatty acyl CoA to its respective fatty alcohol, constituting the first enzyme of this type discovered in a bacterium. The process of triacylglyceride production in microbes is fairly well understood; however, the process that regulates this production has not yet been fully explored. As part of this research, the model yeast organism, Yarrowea lipolytica, is utilized to identify essential genes for citrate transport that if removed could result in increasing triacylglyceride production in vivo.

Alkaline conditions induced by algae growth in wastewater stabilization ponds create deprotonated ammonium ions that result in ammonia gas (NH3) volatilization. If algae are utilized to remediate wastewater through uptake of phosphorus, the resulting nitrogen loss will hinder this process because algae generally require a stoichiometric molar ratio of N16P1. Lower ratios of N/P due to loss of ammonia gas will limit the growth and yield of algae, and therefore will reduce phosphorus removal from the water phase into the algae phase. In order to reduce nitrogen loss through volatilization, an ammonium selective zeolite, clinoptilolite, can be used to sequester nitrogen from the water phase as ammonium ion and in a form that is bioavailable for uptake and growth of algae. A novel algae biofilm rotating photo bioreactor (RPB) with clinoptilolite integrated to the outermost surface as the substratum for algae biofilm attachment and growth has been designed, constructed, and tested for ammonium capture and algae biomass production, with simultaneous removal of the algal nutrient phosphorus from water. The clinoptilolite‐based RPB (cRPB) provides algal biomass that can serve as feedstock for biofuel production through uptake of zeolite‐based nitrogen and water phase phosphorus.

As technologies advance the study of ocean dynamics, new approaches to vexing problems of scale and process are becoming more widely available. Originally conceived as a tool primarily for indexing the abundance of near-bottom fishes, the Camera-based Assessment and Survey System (C-BASS) may also be an effective tool for monitoring benthic invertebrate resources vulnerable to natural and anthropogenic perturbations, and for characterizing the composition of benthic communities to inform spatial management. Using still images derived from the C-BASS video of benthic transects within the Florida Middle Grounds, I documented the abundance of benthic habitat-forming functional groups—sponges, algae, and corals—and noted taxa that were present in a SCUBA and ROV study conducted a decade earlier. Images were pre-processed using MATLAB computer programming language to correct for light attenuation and scattering in seawater at depth, and examined using ImageJ software and Coral Point Count software or rapid visual assessment methodology to assess image quality and percent cover, respectively. Exploratory data analysis (dissimilarity profile) delineated five habitat types in the northern Florida Middle Grounds, and discriminating benthic cover was identified using similarity percentage analysis: soft corals, fleshy macroalgae, low-relief algae, encrusted rubble, and sand. Hard corals and sponges represented relatively low area cover. A canonical analysis of principle components of in situ environmental measurements, chlorophyll a, turbidity, salinity, slope, and depth highlighted the association of the sand habitat type with greater depths and least amount of slope. Fleshy macroalgae were associated with greater slope, which reflected its presence in transitional areas between sand and reef. Soft coral habitat type was correlated with shallower depths, but also to lower temperature and lower salinity, highlighting the limitations of one-time environmental measurements to the condition of that time and space. A distance-based redundancy analysis of fish species abundance revealed that sponges, soft corals, and hard corals explained some of the variation of Holocentridae spp., angelfishes, and porgy, and that gray snapper appeared to associate with higher measurements of chlorophyll a. A comparison of C-BASS measurements with a coincidental stationary camera survey revealed that a slight shift in view, either from the seafloor to the water column, or from two slightly different positions in the water column, can obscure or reveal benthic cover to varying degrees, suggesting that more imaging could provide more complete representations of the benthic cover. Continued surveys of the benthic composition of the west Florida shelf could elucidate the range of environmental conditions and facilitate further investigations into the fish species associations with biotic cover in these benthic communities.

No description available.