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Mixed Culture of Chlorella Pyrenoidosa TX71105 and a Variant Strain of Bacillus Megaterium

Description: Very little work has been done on bacteria capable of significantly inhibiting algal growth. This thesis reports the research on mixed cultures of a high-temperature strain of algae, Chlorella pyrenoidosa TX71105, and an organism isolated from the air and tentatively identified as a variant strain of Bacillus megaterium.
Date: August 1970
Creator: Yao, Raymond Che-Fong
Partner: UNT Libraries

The Effects of Selected Algicides and Some Coordination Complexes upon the Apparent Photosynthesis of Chlorella Pyrenoidosa

Description: Many experiments have been performed with the Warburg apparatus, or variations of this manometric technique, since Warburg's experiments (52, 53) where the effects of cyanides upon dark reactions and of urethanes upon light reactions of photosynthesis were demonstrated. The same basic techniques were utilized in this research in attempting to determine the effects of some coordination complexes upon the apparent photosynthetic rate of Chlorella pyrenoidosa. A second goal of the present paper was to investigate the potential of the Warburg apparatus as a tool for screening algicidal compounds.
Date: June 1965
Creator: Phelps, Robert G.
Partner: UNT Libraries

Effect of Indole-3-Acetic Acid on the Nucleic Acids of Synchronous Cultures of Chlorella Pyrenoidosa

Description: It was the purpose of this study to investigate the effect of various concentrations of IAA on the nucleic acids of Chlorella pyrenoidosa TX 7-11-05. The time during the life cycle when the greatest effect occurred was investigated by the use of synchronous cultures.
Date: May 1972
Creator: Peterson, James Arthur
Partner: UNT Libraries


Description: The summary of this report is that a substance isolated from Chlorella Pyrenoidosa metabolizing {sup 14}CO{sub 2} in the light, previously believed to be a diphosphate ester of a 2-carboxy-4-pentulose, has now been shown to be a disphosphate of 2-keto-L-gulonic acid. The phosphate groups appear to be attached to two of the carbon atoms 3-6. Evidence is presented suggesting that this compound arises from glucose, or a glucose phosphate, which is not in rapid equilibrium with photosynthetically produced glucose derivatives.
Date: June 1, 1962
Creator: Moses, V.; Ferrier, R.J. & Calvin, M.
Partner: UNT Libraries Government Documents Department

Effects of Mineral Salts on Short-Term Incorporation of CarbonDioxide in Chlorella

Description: Although the functions of the essential major elements in plant metabolism have been studied for many years, little work has been done concerning the effect of these elements during short-term incorporation of radioactive carbon dioxide. This may be of some importance as it has been the general custom during photosynthesis studies in this laboratory to suspend algae in various dilute buffer solutions or in distilled water alone assuming that the salt remaining within the cells from the time of growth in nutrient solution are sufficient in quantity for the cells not to become deficient in one or more of the essential elements during the course of the experiment. There are some indications, however, that the addition of salts to algae suspended in distilled water may have a rapid, pronounced effect on some metabolic system within the plant. Thus, Clendenning, Brown and Eyster (1956) have reported that Nostoc muscorum, if rinsed and resuspended in distilled water, loses most of its photosynthetic capacity, which can, however, be completely restored by the addition of potassium ion in concentrations no greater than a few parts per million. Also, K. Baalorud (personal communication) found that the photosynthetic rate of a marine diatom, when suspended in synthetic magnesium-free water, can be greatly increased by the addition of magnesium salts. In view of these observations it appeared worthwhile to investigate the effects of the addition of the essential elements in those photosynthesis experiments in which the cells are kept in distilled water for varying periods of time.
Date: July 1, 1958
Creator: Holm-Hansen, O.; Nishida, K.; Moses, V. & Calvin, M.
Partner: UNT Libraries Government Documents Department

Cyanide Effects on Carbon Dioxide Fixation in Chlorella

Description: Green algae have been treated with radioactive KCN in an investigation of the effect of cyanide on photosynthesis. A multitude of products have been found to be formed in very short exposures (10 to 15 sec). One of these products has been identified with the product formed when the algae are given radioactive CO{sub 2} and nonradioactive KCN. The same product has been synthesized by a nonenzymatic cyanohydrin addition reaction on ribulose-1, 5-diphosphate. It has been shown to be a 2-carboxy-pentitol (probably mostly ribitol)-1, 5-diphosphate. Upon hydrolysis it gives an hydroxy acid (or mixture of isomers) closely related to hamamelonic acid. The significance of this and the other as yet unidentified products of cyanide interaction with a biological system is discussed with respect to the use of cyanide as an inhibitor.
Date: December 17, 1957
Creator: Rabin, Bernard R.; Shaw, D. F.; Pon, Ning G.; Anderson, J. M. & Calvin, M.
Partner: UNT Libraries Government Documents Department


Description: A study of the incorporation of {sup 14}CO{sub 2} into cell components of synchronously growing Chlorella pyrenoidosa has shown that DNA is synthesized primarily during the latter stages of the cell cycle prior to cell division. RNA was synthesized at an approximately equal rate during each of the three phases of the cell growth studied. No major differences were noted in the incorporation of {sup 14}CO{sub 2} into the soluble cell components in these long-term incorporation studies.
Date: March 8, 1962
Creator: Stange, Luise; Kirk, Martha; Bennett, Edward L. & Calvin, M.
Partner: UNT Libraries Government Documents Department

The Relation of Quantum Requirement in Photosynthesis toRespiration

Description: 1. The r a t e s of photosynthesis and subsequent respiration of Chlorella pyrenoidosa were measured using an oxygen analyzer (sensitive to paramagnetism). The energy absorbed during the photosynthesis periods was determined and the quantum requirement was calculated. 2. Dark respiration r a t e was found to depend on the r a t e of light absorption during the period of photosynthesis, and increased with increasing photosynthesis rate. 3 . The quantum requirement, corrected for respiration, varied from 4. 9 ( a t a ratio of photosynthesis to respiration of 1.4) to 6. 9 (at a r a t i o of 12). Both uncorrected and corrected quantum requirements approach an experimental value of 7. 4 a t high light intensity. 4. The lower quantum requirement obtained a t low light intensity is believed to be due to a relatively greater importance of contribution of energy from respiration t o photosynthesis. An expression i s derived for the relation between this contribution and the enhancement of dark respiration due to the level of photosynthesis to which the plants a r e conditioned. 5. Attempts to obtain the blue -light stimulation of photosynthesis with algae photosynthesizing in r e d light were unsuccessful.
Date: January 21, 1955
Creator: Bassham, James A.; Shibata, Kazuo & Calvin, M.
Partner: UNT Libraries Government Documents Department


Description: The theory that algal oozes could give rise to oil shales is not a recent one. Evidence for this theory rests on the finding that algae have less cellulose and a correspondingly greater proportion of lipids than most plant material. In addition, the contemporary alga Botyrococcus is present in microscopic remains in some organic oozes. Since the algal ooze precursor theory rests primarily on geological and paleobotanical evidence, they have sought to complement this evidence by making a study of the constitutents of various genera of algae at the molecular level and comparing them with the organic constituents isolated and identified in the algal ooze from a Florida lake. They have analyzed the hydrocarbon constituents of four species of algae: the blue-greens, Nostoc and Anacystis, the green algae, Spirogyra and Chlorella.
Date: November 1, 1967
Creator: Han, Jerry; McCarthy, E.D.; Van Hoeven Jr., William; Calvin,Melvin & Bradley, W. H.
Partner: UNT Libraries Government Documents Department

Action and Emission Spectra of the Luminescence of Green PlantMaterials

Description: The action and emission spectra of the delayed light emission from Chlorella, Nostoc, and spinach chloroplasts have been measured. The action spectra for Chlorella and for spinach chloroplasts are quite similar to the absorption spectra of these materials. The action spectrum for Nostoc, on the other hand, shows a relatively low activity for chlorophyll and carotenoids and a high activity for phycocyanin. The emission spectra of these materials demonstrates that the luminescence is the result of a transition between the first excited singlet state and the ground state of chlorophyll. Low-temperature studies suggest that the triplet state of chlorophyll is not involved at all in the luminescence of spinach chloroplasts. There is some indication that part of the light emitted from Nostoc is due to a phycocyanin transition.
Date: December 29, 1957
Creator: Tollin, G.; Fujimori, E. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department


Description: The interaction of actinides with microorganisms has been extensively studied to elucidate migration behavior of actinides in the environments. However, the mechanisms of interaction of microorganisms and actinides are poorly understood. They have been conducting basic science on microbial accumulation of actinides in order to elucidate the environmental behavior of actinides under relevant conditions. The effect of exudates from bacteria cells on the sorption of Eu(III) and Cm(III) by Chlorella vulgaris was studied by a batch method. The pH dependence of log K{sub d} of Eu(III) and Cm(III) for cellulose, major component of C. vulgaris cell, differed from that for C. vulgaris. On the contrary, log K{sub d} of Eu(III) and Cm(III) for cellulose in the solution containing exudates from C. vulgaris cells in a 0.5% NaCl solution showed a similar pH dependence to that by C. vulgaris. These results strongly suggested that exudates affect on the sorption of Eu(III) and Cm(III) on C. vulgaris. Effect of desferrioxamine B (DFO), one of exudates to chelate the insoluble Fe(III), on the sorption of Pu(IV), Th(IV) and Eu(III) by Pseudomonas fluorescens was studied. In the presence of DFO the sorption of Pu(IV), Th(IV) and Eu(III) on the cells increased with a decrease in pH from 7 to 4. In contrast, without DFO most of Pu(IV), Th(IV) and Eu(III) were precipitated from solution. Adsorption of DFO on the cells was negligible in the solution with and without metals. Adsorption of Pu(IV), Th(IV) and Eu(III) on P. fluorescens cells decreased in the order Eu(III) > Th(IV) > Pu(IV), which corresponds to increasing stability constant of the DFO complexes. These results indicate that Th(IV), Pu(IV) and Eu(III) dissociate when in contact with cells, after which the metals are adsorbed.
Date: October 18, 2006
Partner: UNT Libraries Government Documents Department

Overall Energy Considerations for Algae Species Comparison and Selection in Algae-to-Fuels Processes

Description: The controlled growth of microalgae as a feedstock for alternative transportation fuel continues to receive much attention. Microalgae have the characteristics of rapid growth rate, high oil (lipid) content, and ability to be grown in unconventional scenarios. Algae have also been touted as beneficial for CO{sub 2} reuse, as algae can be grown using CO{sub 2} emissions from fossil-based energy generation. Moreover, algae does not compete in the food chain, lessening the 'food versus fuel' debate. Most often, it is assumed that either rapid production rate or high oii content should be the primary factor in algae selection for algae-to-fuels production systems. However, many important characteristics of algae growth and lipid production must be considered for species selection, growth condition, and scale-up. Under light limited, high density, photoautotrophic conditions, the inherent growth rate of an organism does not affect biomass productivity, carbon fixation rate, and energy fixation rate. However, the oil productivity is organism dependent, due to physiological differences in how the organisms allocate captured photons for growth and oil production and due to the differing conditions under which organisms accumulate oils. Therefore, many different factors must be considered when assessing the overall energy efficiency of fuel production for a given algae species. Two species, Chlorella vulgaris and Botryococcus braunii, are popular choices when discussing algae-to-fuels systems. Chlorella is a very robust species, often outcompeting other species in mixed-culture systems, and produces a lipid that is composed primarily of free fatty acids and glycerides. Botryococcus is regarded as a slower growing species, and the lipid that it produces is characterized by high hydrocarbon content, primarily C28-C34 botryococcenes. The difference in growth rates is often considered to be an advantage oiChlorella. However, the total energy captured by each algal species in the same photobioreactor system should be similar at light limited ...
Date: January 1, 2011
Creator: Link, D.; Kail, B.; Curtis, W. & Tuerk,A.
Partner: UNT Libraries Government Documents Department

Sensitive quantitative detection/identification of infectious Cryptosporidium parvum oocysts by signature lipid biomarker analysis

Description: Unique signature lipid biomarkers were found in the acid-fast oocytes of Cryptosporidium parvum. This makes possible the rapid detection/identification and potential infectivity directly from drinking water membrane filtrates.
Date: August 1997
Creator: White, D. C.; Alugupalli, S. & Schrum, D. P.
Partner: UNT Libraries Government Documents Department

Viruses of eukaryotic green algae; Progress report, June 20, 1990--July 1, 1991

Description: Many large polyhedral, dsDNA containing (ca. 330 kb), plaque forming viruses which infect a unicellular, eukaryotic, chlorella-like green alga have been isolated and characterized. The plaque assay, the ability to synchronously infect the host, the short life cycle, and the ability of the viruses to undergo homologous recombination make them excellent model systems for studying many plant cell functions in the manner that bacterial and animal viruses have been used to study bacterial and animal cell functions. These viruses have several unique features including: (1) coding for DNA methyltransferase and site-specific (restriction) endonucleases and (2) unlike other viruses, these viruses appear to code for the enzymes involved in the glycosylation of their glycoproteins.
Date: December 31, 1991
Creator: Van Etten, J.L.
Partner: UNT Libraries Government Documents Department

Biological determinants of photobioreactor design. Second quarterly report, December 1, 1993-February 28, 1994

Description: In the first quarterly report the optimal composition of light was discussed. In this report the intake rates of CO{sub 2} are being investigated. Inlet CO{sub 2} and O{sub 2} concentration was varied and the growth kinetics was studied. It was found that 1% CO{sub 2} concentration is sufficient to support growth of cells up to a concentration of 1 {times} 10{sup 8} cells/mL in flask cultures. This experiment was repeated and the results were found to be consistent. In this report we present the results from one set of experiment.
Date: May 1, 1994
Creator: Palsson, B. O.
Partner: UNT Libraries Government Documents Department