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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Location of aryl sulfatase in Neurospora crassa

Scott, Walter A. January 1970 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1970. / Vita. Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
22

The degradation of 2-hydroxypyridine by cell-free extracts of Arthrobacter pyridinolis

Kolenbrander, Paul Edwin, January 1969 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
23

I. Development of a new assay and inhibitors for human cystathionine beta-synthase II. Asymmetric catalyst development guided by in situ enzymatic screening (ISES) /

Shen, Weijun. January 1900 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2007. / Title from title screen (site viewed Aug. 1, 2007). PDF text: 292 p. : ill. (some col.) UMI publication number: AAT 3256642. Includes bibliographical references. Also available in microfilm and microfiche formats.
24

Effects of sulphite on yeasts, with special reference to intracellular buffering capacity

Maloney, Shane Patrick January 1993 (has links)
No description available.
25

Assessment of the effect of dosing regime and cell culture model on micronucleus induction in in vitro genotoxicity test systems

Chapman, Katherine Emma January 2015 (has links)
No description available.
26

A reassessment of the production of acetone and butanol by Clostridium acetobutylicum in continuous culture

Clarke, Kim Gail January 1987 (has links)
Bibliography: pages 154-195. / The production of acetone and butanol by Clostridium acetobutylicum P 262 was studied in continuous culture under conditions where the nutrients were present in excess of the requirements and the cell growth was limited by the products formed during the fermentation. This system differs from most continuous culture systems used to obtain solvent production where the limitation of a specific nutrient was utilised to limit the cell growth.
27

Microbial and chemical transformations of cannabinoids and related alkyl phenols /

McClanahan, Robert Henry January 1985 (has links)
No description available.
28

A filter paper assay for low cellulase activities and the cultivation of Trichoderma reesei on acid whey and sweet whey permeate

Nordmark, Tor Soren 24 November 1993 (has links)
The traditional filter paper assay for saccharifying cellulase originally described by M. Mandels et al (1976) has been modified to make possible low activity determinations of Trichoderma cellulases. The enzymatic activity appears to decline during a prolonged incubation period if no precautions have been taken. By means of adding bovine serum albumin and potassium chloride as protein stabilizers and sodium azide as an antimicrobial agent filter paper activities in the range from 0.02 to 0.37 (IUPAC assay, 1987) can be estimated by extending the incubation time up to 20 hours. Filter paper activity values obtained by this method may be compared to those obtained by the IUPAC assay by using a conversion factor from 1.4 to 1.7. Acid whey and sweet whey permeate have been investigated as media for growth and metabolite production by Trichoderma reesei QM 9414 using shake flask cultures and spore inocula. In the case of acid whey the mycelial growth after 2 weeks is 13 mg dry weight /ml substrate. The specific growth rate is 0.29/day. The fungus appears to metabolize the whey protein the first 2 weeks. The alkalinity of acid whey rises continuously over a three week period up to a pH of 8.5. In the case of whey permeate the maximal mycelial weight gain is 4.4 mg/ml which appears after 8 days. A rise in net soluble protein level comes after 3-5 days and reaches a maximum value of 0.23 mg/ml after 2 weeks. The pH of whey permeate rises continuously to 7.5 after 3 days and then slowly declines. The net production of cellulases is low on both media. Dilution 1:6 of the acid whey, supplementation with ammonium sulfate and pHadjustments did not enhance the production of cellulases. Acid whey supports a significant growth and sweet whey permeate shows potential for extracellular protein production. A literature review surveys the composition and uses of acid whey, environmental aspects of whey wastes, the fungus Trichoderma reesei, the mode of action of the Trichoderma reesei cellulase system and the structure of cellulose in cotton and wood. / Graduation date: 1994
29

Rapid assay for Bacillus proteinases in raw milk as detected by a simple casein denaturation method

Feijoo, Sergio C. 09 January 1991 (has links)
A casein agar diffusion method was developed to detect and quantify pertinent levels of proteinases produced in raw milk supplies by heat resistant Bacillus sporeformers. In order to optimize the required heat treatment conditions of raw milk samples, trials that involved a combination of different temperatures and times were evaluated. A heat treatment of 75°C for 20 min was the most effective for recovering the highest number of surviving spores. A sporulation broth containing five different minerals and supplemented with 0.2% nonfat dry milk was used to maximize spore production in all heat-treated samples. A β-casein based assay detected proteinase activity from raw milk samples that ranged from 0.093 to 4.034 units/mg which corresponded to zones of β-casein precipitation in the β-casein agar of 5.0 and 15.0 mm respectively, and was compared to Protease Type VIII (from B. licheniformis). This assay correlated well with the fluorescein isothiocyanate casein-labeled assay (FITC), R=0.995 (Protease Type VIII). Proteases of Bacillus origin such as Protease Type IX, X, XV and XXXI were also evaluated but were rejected in favor of a broader range of activity expressed by Protease Type VIII. For an initial set of 370 raw milk samples, no quality deterioration, such as coagulation or bitter taste was observed in heat-treated (75°C for 20 min) and incubated samples (7.2°C for 10 days). However, during the winter season, 18 of 75 incubated samples (7.2°C for 10 days) tasted slightly bitter and exhibited a slight degree of casein precipitation. One sample coagulated but exhibited no proteinase activity on the β-casein agar gel, hence it was considered a false negative. The positive results for proteinase activity from raw Grade A samples tested by the β-casein agar diffusion method did not correlate either with fresh spore counts (R=0.21) or post-heat treatment incubation counts (R=0.03) or with psychrotrophic sporeformer counts (R=0.06). The β-casein agar diffusion method is simple, rapid and sensitive to Bacillus spp. proteinases, but was unreliable in projecting results related to the psychrotrophic sporeformer count. Consequently, further research is required to establish optimum conditions (time and/or temperature) and inoculum volumes into sporulation broth for attainment of a more positive correlation between β-casein agar precipitation zones and psychrotrophic sporeformer populations of either raw or processed milk samples. / Graduation date: 1991
30

Bioaerossóis na indústria farmacêutica / Bioareorols in the pharmaceutical industry

Guilherme Neves Ferreira 27 April 2009 (has links)
Este estudo teve como finalidade, testar uma barreira contra a contaminação microbiológica em placas de contato, utilizadas em monitoramento de salas limpas para fabricação de produtos farmacêuticos estéreis. Durante o ano de 2007, foram realizados testes de contato com a utilização da mencionada barreira, e os resultados foram comparados com dados dos anos de, 2004, 2005 e 2006, quando a barreira não foi utilizada. Os ambientes utilizados para os testes foram duas salas limpas de uma planta farmacêutica localizada no Rio de Janeiro. Nos mencionados ambientes é necessário o uso de uma vestimenta especial, de forma a evitar que partículas do corpo dos operadores, bactérias e fungos, migrem para a superfície externa do uniforme e coloquem em risco a esterilidade dos produtos. Sendo assim, foi proposta a colocação de uma camiseta diretamente sobre a pele do operador durante todo o ano de 2007 de forma a evitar ou reduzir a possibilidade de migração dessas partículas; e os resultados foram comparados com os anos de 2004, 2005 e 2006, quando a camiseta não foi usada. Os testes demonstraram que houve uma redução de cerca de 50% na ocorrência de placas contaminadas. Com relação ao número total de colônias formadas, a redução foi de 75% na comparação com os anos de 2004 e 2005 e de 50% com relação ao ano de 2006 / This study had as objective to test a barrier against microbiological contamination in contact plates that are used in sterile pharmaceutical products clean rooms monitoring. During 2007 the tests were performed and compared with data from, 2004, 2005 and 2006, when the mentioned barrier was not used. The test environments were two clean rooms from a pharmaceutical plant located at Rio de Janeiro. In the mentioned environments the use of special garments is necessary for avoiding that particles from operators bodies, bacteria and most remain in contact with the room environment, adding risk to the sterilized products. So, it was proposed the use of undershirt between the garment and the operator skin for reducing the contact plates contamination during the regular rooms monitoring. This undershirt was used during 2007 and the results were compared with the samples of 2004, 2005 and 2006 when the undershirt was not used. The results demonstrated that it was obtained a reduction of about 50% in relation to contaminated plates. In relation to the total number of colonies the reduction was 75% in comparison with 2004 and 2005, and 50% in comparison with 2006

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