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Production, Characterization, and Antioxidant Activity of Fucoxanthin From the Marine Diatom Odontella Aurita

Description

The production, characterization, and antioxidant capacity of the carotenoid fucoxanthin from the marine diatom Odontella aurita were investigated. The results showed that low light and nitrogen-replete culture medium enhanced the biosynthesis of fucoxanthin. The maximum biomass concentration of 6.36 g L^-1 and maximum fucoxanthin concentration of 18.47 mg g^-1 were…

The production, characterization, and antioxidant capacity of the carotenoid fucoxanthin from the marine diatom Odontella aurita were investigated. The results showed that low light and nitrogen-replete culture medium enhanced the biosynthesis of fucoxanthin. The maximum biomass concentration of 6.36 g L^-1 and maximum fucoxanthin concentration of 18.47 mg g^-1 were obtained in cultures grown in a bubble column photobioreactor (Ø 3.0 cm inner diameter), resulting in a fucoxanthin volumetric productivity of 7.96 mg L^-1 day^-1. A slight reduction in biomass production was observed in the scaling up of O. aurita culture in a flat plate photobioreactor, yet yielded a comparable fucoxanthin volumetric productivity. A rapid method was developed for extraction and purification of fucoxanthin. The purified fucoxanthin was identified as all-trans-fucoxanthin, which exhibited strong antioxidant properties, with the effective concentration for 50% scavenging (EC₅₀) of 1,1-dihpenyl-2-picrylhydrazyl (DPPH) radical and 2,2′-Azino-bis(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical being 0.14 and 0.03 mg mL^-1, respectively. Our results suggested that O. aurita can be a natural source of fucoxanthin for human health and nutrition.

ContributorsXia, Song (Author) / Wang, Ke (Author) / Wan, Linglin (Author) / Li, Aifen (Author) / Hu, Qiang (Author) / Zhang, Chengwu (Author) / Julie Ann Wrigley Global Institute of Sustainability (Contributor)

Created2013-07-23

Pharmaceuticals in the Built and Natural Water Environment of the United States

Description

The known occurrence of pharmaceuticals in the built and natural water environment, including in drinking water supplies, continues to raise concerns over inadvertent exposures and associated potential health risks in humans and aquatic organisms. At the same time, the number and concentrations of new and existing pharmaceuticals in the water…

The known occurrence of pharmaceuticals in the built and natural water environment, including in drinking water supplies, continues to raise concerns over inadvertent exposures and associated potential health risks in humans and aquatic organisms. At the same time, the number and concentrations of new and existing pharmaceuticals in the water environment are destined to increase further in the future as a result of increased consumption of pharmaceuticals by a growing and aging population and ongoing measures to decrease per-capita water consumption. This review examines the occurrence and movement of pharmaceuticals in the built and natural water environment, with special emphasis on contamination of the drinking water supply, and opportunities for sustainable pollution control. We surveyed peer-reviewed publications dealing with quantitative measurements of pharmaceuticals in U.S. drinking water, surface water, groundwater, raw and treated wastewater as well as municipal biosolids. Pharmaceuticals have been observed to reenter the built water environment contained in raw drinking water, and they remain detectable in finished drinking water at concentrations in the ng/L to μg/L range. The greatest promises for minimizing pharmaceutical contamination include source control (for example, inputs from intentional flushing of medications for safe disposal, and sewer overflows), and improving efficiency of treatment facilities.

ContributorsDeo, Randhir P. (Author) / Halden, Rolf (Author) / Biodesign Institute (Contributor)

Created2013-09-11

A Review of Marine Mammal Digestion with Applications for Plastic Ingestion

Description

In an industrialized world that relies heavily on low cost production and packaging produced without a viable end-of-life strategy, the accumulation of non-biodegradable plastics in the environment and particularly the oceans today is an urgent problem of global proportions. Plastics pose a significant threat to marine mammals due to mistaken…

In an industrialized world that relies heavily on low cost production and packaging produced without a viable end-of-life strategy, the accumulation of non-biodegradable plastics in the environment and particularly the oceans today is an urgent problem of global proportions. Plastics pose a significant threat to marine mammals due to mistaken ingestion as well as potential release of plasticizers and other chemicals. However, the interactions and consequences of ingestion of oceanic plastics by marine mammals have not been thoroughly studied. In this literature review, information regarding plastic ingestion by marine mammals was compiled to estimate the magnitude of adverse impacts and identify major knowledge gaps. Using comprehensive Boolean search terms in Web of Science of literature published between 1960 and 2020, it was determined that there were large discrepancies in the amount of research conducted among 10 different categories of marine mammals, with cetaceans being the primary focus group of most studies (70.3). In addition, different areas of the world, such as southern Africa, were found to have a disproportionately small number of studies on plastic impacts on marine mammalian life in their surrounding marine waters. Differences were found in the amount of plastics ingested by marine animals and a hypothesis of explaining these observations was formulated, attributing potential ingestion of plastic to the debris resembling different food sources in the mammals’ diets as well as different feeding mechanisms.

ContributorsFredette-Roman, Cassidy (Author) / Polidoro, Beth (Thesis director) / Rolsky, Charles (Committee member) / Halden, Rolf (Committee member) / School of Life Sciences (Contributor) / School of Mathematical and Natural Sciences (Contributor) / Barrett, The Honors College (Contributor)

Created2020-12

Generation of asd plasmids with a red fluorophore for in vivo imaging

Description

The purpose of my honors thesis project was to generate the tools needed for in vivo imaging by determining the optimal plasmid-fluorophore combination. To determine the optimal plasmid and fluorophore, asd plasmids were constructed with various promoters, origins of replications, and red fluorophores. The optimal asd plasmid for fluorescent in…

The purpose of my honors thesis project was to generate the tools needed for in vivo imaging by determining the optimal plasmid-fluorophore combination. To determine the optimal plasmid and fluorophore, asd plasmids were constructed with various promoters, origins of replications, and red fluorophores. The optimal asd plasmid for fluorescent in vivo imaging was determined by the plasmid stability, growth rate, and growth phase dependence on fluorescent intensity. The end goal is to be able to use the asd plasmid in vaccine strains for the purpose of in vivo imaging of the recombinant attenuated Salmonella vaccine (RASV).

ContributorsEudy, L. Adam (Author) / Curtiss, Roy (Thesis director) / Roland, Kenneth (Committee member) / Forbes, Stephen (Committee member) / Barrett, The Honors College (Contributor) / College of Liberal Arts and Sciences (Contributor)

Created2012-12

Spatial analysis, water quality, and risks associated with abandoned mine lands

Description

Historic mining of heavy metals (HMs) in Arizona has resulted in the creation of abandoned mine lands (AML), which can become sources of contamination and possible risks to human health. The goals of this work were to support the creation of databases useful for AML risk assessment, and to use…

Historic mining of heavy metals (HMs) in Arizona has resulted in the creation of abandoned mine lands (AML), which can become sources of contamination and possible risks to human health. The goals of this work were to support the creation of databases useful for AML risk assessment, and to use Patagonia, Arizona as a case study to assess the relationship between water quality and proximity to AML sites. The of risk assessment database for AML contains risk calculation results from published national and international studies, with 4,667 data points from 75 unique papers. From the data visualization, 18 environmental contaminants, Cd, Co, Cr, Cu, F-, Fe, Hg, Mn, NH4+, Ni, Pb, Sb, Se, Tl, V, W, and Zn, had data points with non-carcinogenic health risks above commonly used health risk benchmarks. Comparatively, of the studies that computed a carcinogenic health risk, the seven contaminants evaluated (As, Cd, Cr, Cr(VI), Hg, Ni, Pb) all had data exceeding a 10-6 cancer risk (CR) reference value. In Patagonia, Pb, Cu, and Zn were measured at higher concentrations when closer to AML sites than at points downstream. These findings were corroborated by a comparison of contaminant concentrations across the watershed area, which additionally suggested a higher surface water solubility of HMs such as boron and barium.

ContributorsTerrones, Wesley (Author) / Hamilton, Kerry (Thesis director) / Halden, Rolf (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainable Engineering & Built Envirnmt (Contributor)

Created2024-05