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Scientific Considerations of Olestra as a Fat Substitute (open access)

Scientific Considerations of Olestra as a Fat Substitute

Olestra is, a sucrose polyester, a noncaloric fat substitute, made from sucrose and several fatty acid esters. It has been approved by the FDA as a food additive used in preparing low-fat deep-frying foods such as savory snacks. Available literature on olestra was evaluated that had both positive and negative connotations. Clinical trials in numerous species of animals including humans were conducted to determine if olestra would affect the utilization and absorption of macro- and micronutrients; the effects of olestra on growth, reproduction, or its toxicity were also examined. The roles of olestra as a fat substitute, how it could effect on humans and the environment, and the potential impacts from its use in large amounts were assessed. Olestra can be removed from the environment by aerobic bacteria and fungi which may be isolated from activated sludge and soils.
Date: December 1999
Creator: Rattagool, Kullakan
System: The UNT Digital Library
Biodegradation of Certain Petroleum Product Contaminants in Soil and Water By Selected Bacteria (open access)

Biodegradation of Certain Petroleum Product Contaminants in Soil and Water By Selected Bacteria

Soil contamination by gasoline underground storage tanks is a critical environmental problem. The results herein show that in situ bioremediation using indigenous soil microorganisms is the method of choice. Five sites were selected for bioremediation based on the levels of benzene, toluene, ethylbenzene and xylene and the amount of total petroleum hydrocarbons in the soil. Bacteria capable of degrading these contaminants were selected from the contaminated sites and grown in 1,200 I mass cultures. These were added to the soil together with nutrients, water and air via PVC pipes.
Date: December 1995
Creator: Nevárez-Moorillón, Guadalupe Virginia
System: The UNT Digital Library
The Detection of Poliovirus in Denton Sewage by Immunofluorescence and Immunodiffusion Techniques (open access)

The Detection of Poliovirus in Denton Sewage by Immunofluorescence and Immunodiffusion Techniques

Several final sewage effluents from the Denton Disposal Plant were demonstrated to contain Poliovirus types II and III. Pleated encapsulated filters at pH3.5 enhanced the recovery of the Poliovirus at a higher tier in comparison with nitrocellulose filter (Millipore) and glass fiber filter of pore size 0.45u. This thesis explores problems that face us today in our quest to eliminate viral pathogens from the natural and waste water needed for human, domestic, and industrial consumption. Preliminary experiments concern the use of immunofluorescence, and immunodiffusion techniques as a means of poliovirus identification, which invariably suggests that these techniques may be useful as rapid screening procedures of water samples for presence of potentially pathogenic viruses.
Date: August 1975
Creator: Olaiya, Felix Ayodele
System: The UNT Digital Library
Degradation of Humic Substances by Aquatic Bacteria (open access)

Degradation of Humic Substances by Aquatic Bacteria

A variety of aquatic bacteria were isolated and tested for their ability to degrade humic substances and their aromatic residues/monomers which serve as precursors of the trihalomethanes (THMs) found in chlorinated drinking waters. The majority of them were Gram-negative, oxidative types dominated by pseudomonads. Most of the 146 isolates were found to utilize as their sole source of carbon several or more of ten aromatic compounds known to be products of degradation of humus and also to be precursors of THMs. The aromatics tested, with percent of the isolates utilizing the compound in parentheses, were: p-hydroxybenzoate (49), vanillic acid (48), 3,5-dihydroxybenzoic acid (16), syringic acid (19), vanillin (30), benzoic acid (27), ferulic acid (34), resorcinol (9), catechol (8) and protocatechuic acid (27).
Date: August 1985
Creator: Baiu, Saleh Hamed Salem
System: The UNT Digital Library
Induction of Interferon Messenger RNA and Expression of Cellular Oncogenes in Human Lymphoblastoid Cells (open access)

Induction of Interferon Messenger RNA and Expression of Cellular Oncogenes in Human Lymphoblastoid Cells

The purposes of this study was to demonstrate the induction of alpha interferon mRNA in Sendai virus-induced Namalava cells, to follow the level of alpha interferon mRNA synthesis at the transcriptional level, and to determine whether the Namalava cell line expresses the c-myc oncogene and to what degree. The amount of c-myc message deteted in Namalva cell RNA was about one-tenth that of Daudi cell RNA, whereas no difference in the amount of the c-Ha-ras message was observed between the two cell lines.
Date: December 1986
Creator: Mahmoudi, Massoud
System: The UNT Digital Library
Comparative Biochemistry and Evolution of Aspartate Transcarbamoylase from Diverse Bacteria (open access)

Comparative Biochemistry and Evolution of Aspartate Transcarbamoylase from Diverse Bacteria

Aspartate transcarbamoylase (ATCase) catalyzes the first committed step in pyrimidine biosynthesis. Bacterial ATCases are divided into three classes, A, B and C. Class A ATCases are largest at 450-500, are. dodecamers and represented by Pseudomonas ATCase. The overlapping pyrBC' genes encode the Pseudomonases ATCase, which is active only as a 480 kDa dodecamer and requires an inactive pyrC'-encoded DHOase for ATCase activity. ATCase has been studied in two non-pathogenic members of Mycobacterium, M. smegmatis and M. phlei. Their ATCases are dodecamers of molecular weight 480 kDa, composed of six PyrB and six PyrC polypeptides. Unlike the Pseudomonas ATCase, the PyrC polypeptide in these mycobacteria encodes an active DHOase. Moreover, the ATCase: DHOase complex in M. smegmatis is active both as the native 480 kDa and as a 390 kDa complex. The latter lacks two PyrC polypeptides yet retains ATCase activity. The ATCase from M. phlei is similar, except that it is active as the native 480 kDa form but also as 450,410 and 380 kDa forms. These complexes lack one, two, and three PyrC polypeptides, respectively. By contrast,.ATCases from pathogenic mycobacteria are active only at 480 kDa. Mycobacterial ATCases contain active DHOases and accordingly. are placed in class A1 . …
Date: May 1999
Creator: Hooshdaran, Massoumeh Ziba
System: The UNT Digital Library