Academic literature on the topic 'Yeast'

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Journal articles on the topic "Yeast"

1

DICKSON, R. C. "Yeasts: Yeast Cell Biology." Science 235, no. 4786 (January 16, 1987): 374. http://dx.doi.org/10.1126/science.235.4786.374.

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Tran, Thierry, Chloé Roullier-Gall, François Verdier, Antoine Martin, Philippe Schmitt-Kopplin, Hervé Alexandre, Cosette Grandvalet, and Raphaëlle Tourdot-Maréchal. "Microbial Interactions in Kombucha through the Lens of Metabolomics." Metabolites 12, no. 3 (March 9, 2022): 235. http://dx.doi.org/10.3390/metabo12030235.

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Kombucha is a fermented beverage obtained through the activity of a complex microbial community of yeasts and bacteria. Exo-metabolomes of kombucha microorganisms were analyzed using FT-ICR-MS to investigate their interactions. A simplified set of microorganisms including two yeasts (Brettanomyces bruxellensis and Hanseniaspora valbyensis) and one acetic acid bacterium (Acetobacter indonesiensis) was used to investigate yeast–yeast and yeast–acetic acid bacterium interactions. A yeast–yeast interaction was characterized by the release and consumption of fatty acids and peptides, possibly in relationship to commensalism. A yeast–acetic acid bacterium interaction was different depending on yeast species. With B. bruxellensis, fatty acids and peptides were mainly produced along with consumption of sucrose, fatty acids and polysaccharides. In opposition, the presence of H. valbyensis induced mainly the decrease of polyphenols, peptides, fatty acids, phenolic acids and putative isopropyl malate and phenylpyruvate and few formulae have been produced. With all three microorganisms, the formulae involved with the yeast–yeast interactions were consumed or not produced in the presence of A. indonesiensis. The impact of the yeasts’ presence on A. indonesiensis was consistent regardless of the yeast species with a commensal consumption of compounds associated to the acetic acid bacterium by yeasts. In detail, hydroxystearate from yeasts and dehydroquinate from A. indonesiensis were potentially consumed in all cases of yeast(s)–acetic acid bacterium pairing, highlighting mutualistic behavior.
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Sandven, Per, and Jørgen Lassen. "Importance of Selective Media for Recovery of Yeasts from Clinical Specimens." Journal of Clinical Microbiology 37, no. 11 (1999): 3731–32. http://dx.doi.org/10.1128/jcm.37.11.3731-3732.1999.

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We compared the recovery of yeasts from clinical specimens cultured on routine bacteriological media to the recovery of yeast from specimens cultured on a selective fungal medium (Sabouraud agar). The use of Sabouraud agar was especially important in cases of mixed cultures, since in such cases yeast was recovered on bacteriological media from only 50% of 44 yeast-positive pus specimens and from 22.5% of 22 yeast-positive throat specimens. The use of a selective fungal medium is therefore necessary to ensure the detection of yeast in specimens containing a mixture of bacteria and yeasts. As a result, clinicians must request yeast isolation when clinically indicated, and the microbiological laboratory must add a selective fungal medium when clinically significant yeasts are likely to be encountered. It is also important that selective fungal media be used in clinical studies of yeast infections.
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Allen, Tom W., Leon L. Burpee, and James W. Buck. "In vitro attachment of phylloplane yeasts to Botrytis cinerea, Rhizoctonia solani, and Sclerotinia homoeocarpa." Canadian Journal of Microbiology 50, no. 12 (December 1, 2004): 1041–48. http://dx.doi.org/10.1139/w04-100.

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The ability of yeasts to attach to hyphae or conidia of phytopathogenic fungi has been speculated to contribute to biocontrol activity on plant surfaces. Attachment of phylloplane yeasts to Botrytis cinerea, Rhizoctonia solani, and Sclerotinia homoeocarpa was determined using in vitro attachment assays. Yeasts were incubated for 2 d on potato dextrose agar (PDA) prior to experimentation. A total of 292 yeasts cultured on PDA were screened for their ability to attach to conidia of B. cinerea; 260 isolates (89.1%) attached to conidia forming large aggregates of cells, and 22 isolates (7.5%) weakly attached to conidia with 1 or 2 yeast cells attached to a few conidia. Ten yeasts (3.4%), including 8 isolates of Cryptococcus laurentii, 1 isolate of Cryptococcus flavescens, and an unidentified species of Cryptococcus, failed to attach to conidia. All non-attaching yeasts produced copious extracellular polysaccharide (EPS) on PDA. Seventeen yeast isolates did not attach to hyphal fragments of B. cinerea, R. solani, and S. homoeocarpa after a 1 h incubation, but attachment was observed after 24 h. Culture medium, but not culture age, significantly affected the attachment of yeast cells to conidia of B. cinerea. The 10 yeast isolates that did not attach to conidia when grown on agar did attach to conidia (20%–57% of conidia with attached yeast cells) when cultured in liquid medium. Attachment of the biocontrol yeast Rhodotorula glutinis PM4 to conidia of B. cinerea was significantly greater at 1 × 107 yeast cells·mL–1 than at lower concentrations of yeast cells. The ability of yeast cells to attach to fungal conidia or hyphae appears to be a common phenotype among phylloplane yeasts.Key words: adhesion, biological control, Cryptococcus laurentii, Rhodotorula glutinis.
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Pan, Hao, Ryoichi Takeshita, Noriaki Saigusa, Ngo Thi Phuong Dung, Aporn Wongwicharn, and Yuji Teramoto. "Production and Antioxidative Activity of Alcoholic Beverages Made From Newly Isolated Vietnamese Men Yeast." International Journal of Biomass and Renewables 4, no. 2 (December 25, 2015): 17. http://dx.doi.org/10.61762/ijbrvol4iss2art13904.

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Fermentation yeast was newly isolated from a traditional Vietnamese microbial starter for brewing alcoholic beverages, called men. The isolated yeast was identified as a strain of the Saccharomyces cerevisiae and designated as S. cerevisiae Y3. The alcoholic beverage made with 3 yeast strains, Y3, NP01, and K7 from uncooked and cooked nonglutinous rice grains had an ethanol concentration of approximately 11.6 to 14.5% (v/v). Resulting alcoholic beverages made with Y3, NP01, and K7 yeasts had antioxidative activity. The DPPH radical scavenging activity of the alcoholic beverages made with 3 yeast strains is equivalent to approximately 500 to 600 μM Trolox. The DPPH radical scavenging activity of the alcoholic beverage made with Y3 yeast was higher than that of the alcoholic beverage made with NP01 and K7 yeasts. The inhibitory activity of lipid peroxidation of the alcoholic beverages made with Y3 and NP01 yeasts was higher than that of the alcoholic beverages made with K7 yeast. Keywords: men, fermentation yeast, antioxidative activity, uncooked fermentation
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Shaghaghi-Moghaddam, Reza, Hoda Jafarizadeh-Malmiri, Parviz Mehdikhani, Sepide Jalalian, and Reza Alijanianzadeh. "Screening of the five different wild, traditional and industrial Saccharomyces cerevisiae strains to overproduce bioethanol in the batch submerged fermentation." Zeitschrift für Naturforschung C 73, no. 9-10 (September 25, 2018): 361–66. http://dx.doi.org/10.1515/znc-2017-0180.

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Abstract Efforts to produce bioethanol with higher productivity in a batch submerged fermentation were made by evaluating the bioethanol production of the five different strains of Saccharomyces cerevisiae, namely, NCYC 4109 (traditional bakery yeast), SFO6 (industrial yeast), TTCC 2956 (hybrid baking yeast) and two wild yeasts, PTCC 5052 and BY 4743. The bioethanol productivity and kinetic parameters for all five yeasts at constant fermentation conditions, during 72 h, were evaluated and monitored. The obtained results indicated that compared to the wild yeasts, both traditional bakery (NCYC 4109) and industrial (SFO6) yeasts had higher bioethanol productivity (0.9 g/L h). Significant (p<0.05) differences between biomass concentration of NCYC 4109 yeast and those of other yeasts 30 h after start of fermentation, and its high bioethanol concentration (59.19 g/L) and yield over consumed sugars (77.25%) were highlighted among all the studied yeasts. Minimum bioethanol productivity was obtained using yeasts PTCC 5052 (0.7 g/L h) and TTCC 2956 (0.86 g/L h). However, maximum yield over consumed sugar was obtained using the yeast TTCC 2956 (79.41%).
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Hamby, Kelly A., Alejandro Hernández, Kyria Boundy-Mills, and Frank G. Zalom. "Associations of Yeasts with Spotted-Wing Drosophila (Drosophila suzukii; Diptera: Drosophilidae) in Cherries and Raspberries." Applied and Environmental Microbiology 78, no. 14 (May 11, 2012): 4869–73. http://dx.doi.org/10.1128/aem.00841-12.

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ABSTRACTA rich history of investigation documents variousDrosophila-yeast mutualisms, suggesting thatDrosophila suzukiisimilarly has an association with a specific yeast species or community. To discover candidate yeast species, yeasts were isolated from larval frass, adult midguts, and fruit hosts ofD. suzukii. Terminal restriction fragment length polymorphism (TRFLP) technology and decimal dilution plating were used to identify and determine the relative abundance of yeast species present in fruit juice samples that were either infested withD. suzukiior not infested. Yeasts were less abundant in uninfested than infested samples. A total of 126 independent yeast isolates were cultivated from frass, midguts, and fruit hosts ofD. suzukii, representing 28 species of yeasts, withHanseniaspora uvarumpredominating. This suggests an association betweenD. suzukiiandH. uvarumthat could be utilized for pest management of the highly pestiferousD. suzukii.
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Lowes, K. F., C. A. Shearman, J. Payne, D. MacKenzie, D. B. Archer, R. J. Merry, and M. J. Gasson. "Prevention of Yeast Spoilage in Feed and Food by the Yeast Mycocin HMK." Applied and Environmental Microbiology 66, no. 3 (March 1, 2000): 1066–76. http://dx.doi.org/10.1128/aem.66.3.1066-1076.2000.

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ABSTRACT The yeast Williopsis mrakii produces a mycocin or yeast killer toxin designated HMK; this toxin exhibits high thermal stability, high pH stability, and a broad spectrum of activity against other yeasts. We describe construction of a synthetic gene for mycocin HMK and heterologous expression of this toxin inAspergillus niger. Mycocin HMK was fused to a glucoamylase protein carrier, which resulted in secretion of biologically active mycocin into the culture media. A partial purification protocol was developed, and a comparison with native W. mrakii mycocin showed that the heterologously expressed mycocin had similar physiological properties and an almost identical spectrum of biological activity against a number of yeasts isolated from silage and yoghurt. Two food and feed production systems prone to yeast spoilage were used as models to assess the ability of mycocin HMK to act as a biocontrol agent. The onset of aerobic spoilage in mature maize silage was delayed by application of A. niger mycocin HMK on opening because the toxin inhibited growth of the indigenous spoilage yeasts. This helped maintain both higher lactic acid levels and a lower pH. In yoghurt spiked with dairy spoilage yeasts, A. niger mycocin HMK was active at all of the storage temperatures tested at which yeast growth occurred, and there was no resurgence of resistant yeasts. The higher the yeast growth rate, the more effective the killing action of the mycocin. Thus, mycocin HMK has potential applications in controlling both silage spoilage and yoghurt spoilage caused by yeasts.
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Brr, A. A. H., and A. G. Mahmoud Y. "Anti-yeast effects of some plant extracts on yeasts contaminating processed poultry products in Egypt." Czech Journal of Food Sciences 23, No. 1 (November 15, 2011): 12–19. http://dx.doi.org/10.17221/3366-cjfs.

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A total of 60 random samples of fresh chicken burger, fillet, and luncheon (20 of each) were collected from markets at Tanta city. The average total yeast counts (cfu/g) in burger, fillet, and luncheon samples were 2.7 &times; 10<sup>6 </sup>&plusmn; 1.1 &times; 10<sup>6</sup>, 2.1&nbsp;&times; 10<sup>5</sup> &plusmn; 0.9 &times; 10<sup>5</sup>, and 1.4 &times; 10<sup>7</sup> &plusmn; 0.7 &times; 10<sup>7</sup>, respectively. A total of 158 yeast isolates of 23 species were isolated and identified. Candida, Cryptococcus, Debaromyces, Issatchenkia, Pichia, Rhodotorula, Saccharomyces, Trichosporon and Yarrowia species were recovered from the examined samples of fresh chicken meat products in varying percentages ranging from 5% to 50%. The tested plant extracts of cinnamon, clove and thyme revealed a potent anti-yeast activity against C. albicans, D. hansenii and S. cerevisiae at 20% concentration, and a moderate inhibitory activity against these yeast strains at 10% concentration, while garlic extract had a lesser inhibitory effect on the yeast strains tested at the same concentration. Moreover, thyme, cinnamon and clove extracts had a complete inhibitory effect on chicken fillet inoculated with Candida albicans when incubated at 5&deg;C and 25&deg;C. &nbsp;
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Pang, Yuanxiang, Hailiang Zhang, Haoyu Wen, Hongbing Wan, Hao Wu, Ying Chen, Shengshuo Li, et al. "Yeast Probiotic and Yeast Products in Enhancing Livestock Feeds Utilization and Performance: An Overview." Journal of Fungi 8, no. 11 (November 11, 2022): 1191. http://dx.doi.org/10.3390/jof8111191.

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The intensive use of antibiotics as growth-promoting agents in animal production has resulted in the spread of animal antibiotic resistance and possibly human antibiotic resistance. Based on this premise, it is significant to explore an alternative approach to preventing infectious diseases and promoting animal growth and health. Yeast as the main natural growth promoter in livestock nutrition has been extensively studied for decades. Numerous yeasts and yeast-containing products are produced, marketed, and used in animal feed as providers of nutrient sources, probiotics, and nutrients or serve distinct nutritional functions. A large amount of scientific research suggests that yeasts and their derivatives may be good for animal growth performance and health, especially when animals are housed in poor sanitation or are suffering from disease. However, when yeasts are used as a surrogate for livestock antibiotics, the results vary according to several factors, including yeast species, yeast product components, feed ingredients, animal category, type of symptoms, and differences in the rearing environment. In this review, the effects of different yeasts on different animals will be reviewed. The types of widely used yeast products, their functional characteristics, and application effects will be discussed in order to provide a reference for the development and application of yeast feed products.
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Dissertations / Theses on the topic "Yeast"

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Yap, Nicholas Andrew. "The sensitivity of yeasts to killer yeast toxins : with focus on the killer yeast Pichia membranifaciens /." Title page, abstract and contents only, 2000. http://web4.library.adelaide.edu.au/theses/09APSP/09apspy25.pdf.

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Brady, Dean. "Bioaccumulation of metal cations by yeast and yeast cell components." Thesis, Rhodes University, 1993. http://hdl.handle.net/10962/d1004107.

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The aim of the project was to determine whether a by-product of industrial fermentations, Saccharomyces cerevisiae, could be utilized to bioaccumulate heavy metal cations and to partially define the mechanism of accumulation. S. cerevisiae cells were found to be capable of accumulating Cu²⁺in a manner that was proportional to the external Cu²⁺ concentration and inversely proportional to the concentration of biomass. The accumulation process was only minimally affected by temperature variations between 5 and 40°C or high ambient concentrations of sodium chloride. The accumulation process was however considerably affected by variations in pH, bioaccumulation being most efficient at pH 5 - 9 but becoming rapidly less so at either extreme of pH. Selection for copper resistant or tolerant yeast diminished the yeast's capacity for Cu²⁺ accumulation. For this and other reasons the development of heavy metal tolerance in yeasts was deemed to be generally counterproductive to heavy metal bioaccumulation. The yeast biomass was also capable of accumulating other heavy metal cations such as c0²⁺ or Cd²⁺. The yeast biomass could be harvested after bioaccumulation by tangential filtration methods, or alternatively could be packed into hollow fibre microfilter membrane cartridges and used as a fixed-bed bioaccumulator. By immobilizing the yeast in polyacrylamide gel and packing this material into columns, cu²⁺, C0²⁺ or Cd²⁺ could be removed from influent aqueous solutions yielding effluents with no detectable heavy metal, until breakthrough point was reached. This capacity was hypothesized to be a function of numerous "theoretical plates of equilibrium" within the column. The immobilized biomass could be eluted with EDTA and recycled for further bioaccumulation processes with minor loss of bioaccumulation capacity. Yeast cells were fractionated to permit identification of the major cell fractions and molecular components responsible for metal binding. Isolation of the yeast cell walls permitted investigation of their role in heavy metal accumulation. Although the amino groups of chitosan and proteins, the carboxyl groups of proteins, and the phosphate groups of phosphomannans were found to be efficient groups for the accumulation of copper, the less effective hydroxyl groups of the carbohydrate polymers (glucans and mannans) had a similar overall capacity for copper accumulation owing to their predominance in the yeast cell wall. The outer (protein-mannan) layer of the yeast cell wall was found to be a better Cu²⁺ chelator than the inner (chitinglucan) layer. It appeared that the physical condition of the cell wall may be more important than the individual macromolecular components of the cell wall in metal accumulation. It was apparent that the cell wall was the major, if not the sole contributor to heavy metal accumulation at low ambient heavy metal concentrations. At higher ambient metal concentrations the cytosol and vacuole become involved in bioaccumulation. Copper and other metals caused rapid loss of 70% of the intracellular potassium, implying permeation of the plasma membrane. This was followed by a slower "leakage" of magnesium from the vacuole which paralleled Cu²⁺ accumulation, suggesting that it may represent some form of ion-exchange. An intracellular copper chelating agent of approximately 2 kDalton molecular mass was isolated from copper tolerant yeast. This chelator was not a metallothionein and bound relatively low molar equivalents of copper compared to those reported for metallothionein. Treatment of the biomass with hot alkali yielded two biosorbents, one soluble (which could be used as a heavy metal flocculent), and an insoluble biosorbent which could be formed into a granular product to be used in fixed-bed biosorption columns. The granular biosorbent could accumulate a wide range of heavy metal cations in a semispecific manner and could be stored in a dehydrated form indefinitely, and rehydrated when required. Bioaccumulation by live algae was investigated as an alternative to yeast based processes. Various strains of algae, of which Scenedesmus and Selenastrum were the most effective, were found to be capable of accumulating heavy metals such as Cu²⁺, Pb²⁺ and Cr³⁺.
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Louie, Gordon V. "Structural studies of wild-type and variant yeast iso-1-cytochromes c." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/30997.

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The crystal structure of yeast (Saccharomyces cerevisiae) iso-1- cytochrome c has been determined through molecular replacement techniques, and refined against X-ray diffraction data in the resolution range 6.0-1.23 Å to a crystallographic R-factor of 0.192. The yeast iso-1-cytochrome c molecule has the typical cytochrome c fold, with the polypeptide chain organized into five α-helices and a series of loops which serve to enclose almost completely the heme prosthetic group within a hydrophobic pocket Comparison of the structures of yeast iso-1-, tuna and rice cytochromes c shows that the polypeptide backbone fold, intramolecular hydrogen bonding, conformation of side chains and particularly packing within the heme crevice of protein groups against the heme moiety are very similar in the three proteins. Significant structural differences among the three cytochromes c can be explained by differences in amino acid sequence. X-ray crystallographic techniques have also been used to study the effect of single-site amino acid substitutions at Phe82 and at Arg38 in iso-1-cytochrome c. The structures of the various variant iso-1-cytochromes c have been determined at nominal resolutions in the range 2.8 to 1.76 Å. Conspicuous structural perturbations in the neighborhood of the substituted side chain are evident in all of the variant proteins. In wild-type iso-1-cytochrome c, the phenyl ring of Phe82 is positioned adjacent and approximately parallel to the heme group, and occupies a non-polar cavity within the heme crevice. In the Ser82 variant, a channel extending from the surface of the molecule down into the heme crevice is created. In the Gly82 variant, the polypeptide backbone has refolded into the space formerly occupied by the phenyl ring of Phe82. Steric conflicts prevent both the phenolic ring of Tyr82 and the side chain of Ile82 from being completely accommodated within the pocket normally occupied by a phenyl ring. Substitution of alanine at position 38 causes a slight reorganization of the hydrogen bonding network in which Arg38 normally participates, and also exposes to external solvent a normally buried propionic acid group of the heme. The altered functional properties of the position 82 variant proteins have been interpreted with respect to the observed structural perturbations. The drop in reduction potential, most notably for the Ser82 and Gly82 variants, can be explained by the elevated heme environment polarity arising from the increased access of solvent or polar protein groups to the heme pocket The reduced stability of the heme crevice, as indicated by lowered pKa's for alkaline isomerization, is likely due to the disruption of stabilizing packing forces formed by the Phe82 phenyl ring within its hydrophobic cavity. The lowered activity, in comparison to the wild-type protein and the Tyr82 variant, for electron transfer with Zn+-cytochrome c peroxidase is attributed to the loss of an aromatic group positioned adjacent to the heme group. The altered surface topography of the variant proteins (particularly the Gly82, Tyr82 and Ile82 variants) may further hinder productive complex formation between cytochrome c and its redox partners. These results suggest that the invariant Phe82 contributes in at least three ways to the proper functioning of cytochrome c. It has an important structural role in maintaining the integrity of the heme crevice and in establishing the appropriate heme environment The phenyl ring of Phe82 may also be required for efficient movement of an electron to and from the heme of cytochrome c. Finally, Phe82 may have a role in forming intermolecular interactions with enzymic redox partners of cytochrome c.
Medicine, Faculty of
Biochemistry and Molecular Biology, Department of
Graduate
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Samuels, Michael L. "Yeast stress signalling." Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368116.

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Hansen, Christine S. "Construction of galactose assimilating, carotenoid producing yeasts by protoplast fusion." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/27935.

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Protoplasts were prepared from two yeast strains P. rhodozyma (ATCC 24202) and K. fragilis (ATCC 8455). Protoplasts prepared from P. rhodozyma were facilitated by prior growth of the cells in a media containing S-(2-aminoethyl)-L-cysteine. Protoplasts from these two yeast genera were fused either by the use of electrofusion or polyethylene glycol treatment. Stable carotenoid producing cell lines were selected by growth at 30°C on yeast nitrogen base plus galactose. Selected single fusants display taxonomic characteristics common to both genera with a cellular morphology and a carotenoid composition similar to that of P. rhodozyma.
Land and Food Systems, Faculty of
Graduate
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Nayyar, Ashima. "Yeast flocculation : understanding cell surface structure-function relationships in industrial yeast strains." Thesis, Abertay University, 2015. https://rke.abertay.ac.uk/en/studentTheses/cec13693-e667-4426-ba6c-6873e5c2b642.

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Adhesion properties of microorganisms are crucial for many essential biological processes such as sexual reproduction, tissue or substrate invasion, biofilm formation and cell-cell aggregation. One of such controlled forms of cellular adhesion in yeast that occurs preferentially in the liquid environments is a process of asexual aggregation of cells which is also referred to as flocculation. The timing during growth and the causes of onset of yeast flocculation are of commercial interest to the brewing industry, as flocculation can determine the degree of attenuation of the wort. Early or premature flocculation is one common causes of ‘hung’ or ‘stuck’ fermentations giving rise to sweeter beer whereas a lack or delay in flocculation can cause filtration difficulties and some problems in obtaining a bright sparkling beer; in addition, the presence of excess yeast in beer during ageing can cause off flavours due to yeast autolysis. Despite this commercial interest, limited information is available about the onset of flocculation and the various factors that may be responsible in the process. In particular, what are the signals that trigger flocculation? Adhesion properties applicable in improving yeast biotechnology are dependent directly or indirectly on characteristics of cellular surfaces, usually the outer layer of the cell wall. Change in the structure and or composition of the cell wall leads to changes in the microbial adhesion properties. Exploring more into the cell wall and studying the nanoscale structure of the yeast cell wall would thus be beneficial to augment our understanding of flocculation.
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Milošević, Tamara. "Yeast pathology : a systemic analysis of death and aging in budding yeast." Paris 5, 2011. http://www.theses.fr/2011PA05T040.

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Le vieillissement et la mort font partie intégrante de la vie et jouent un rôle dans l’histoire de vie d’un organisme en influençant à la fois la structure de sa population et son évolution. Le vieillissement chez la levure a été largement étudié en observant l’espérance de vie réplicative et chronologique, alors que la mort a été décrite comme un processus similaire à la nécrose et l’apoptose. Malgré le fait que le vieillissement entraîne la mort, les organismes peuvent aussi mourir prématurément à la suite de maladies. Afin de comprendre l’étendue des changements morphologiques précédant la mort, j’ai analysé l’ensemble des 1091 mutants de gènes essentiels de la levure au niveau cellulaire. J’ai décrit de manière quantitative le caractère essentiel de chaque gène et documenté les caractéristiques phénotypiques des cellules et colonies comme une représentation vivide des changements cellulaires chez des mutants de levures avant qu’ils ne cessent de se diviser puis qu’ils ne meurent. Bien que certains phénotypes de mutants de gènes essentiels puissent être expliqués au moyen des connaissances actuelles sur les gènes en question, la complexité des modèles de mort nous montre que la mort à l’échelle cellulaire unique est très peu comprise. Néanmoins il est clair que chez la levure les symptômes résultant d’une maladie génétique diffèrent de ceux résultant du vieillissement normal de la cellule. Ce travail de recherche montre ainsi l’importance des analyses au niveau de la cellule unique de phénomènes complexes biologiques et offre un point de départ pour une exploration future des maladies endogènes et des mécanismes liés au vieillissement entraînant la mort
Aging and death are integral parts of life and as such play a role in individual organism’s life history, influencing at the same time the structure of population and its evolution. Aging in yeast has been extensively studied by looking at both replicative and chronological lifespans, while death of yeast cells has been described in terms of necrosis- and apoptosis-like processes. Despite the fact that aging eventually results in death, organisms can also die prematurely because of the disease. In order to understand the possible repertoire of morphological changes preceding death, I have systematically analyzed all 1091 yeast essential gene mutants on the cellular level. I have quantitatively described the degree of essentiality for each essential gene, and documented the phenotypic characteristics of cells and the colonies as a vivid representation of cellular changes budding yeast mutants experience before they stop dividing and eventually die. Although some phenotypes of essential gene mutants can be explained using available knowledge about the genes in question, the complexity of dying patterns shows us that death on a single-cell level is still poorly understood. Nevertheless, it is clear that the symptoms of the genetic disease in yeast differ from the symptoms of normal yeast cell aging. This research emphasizes the importance of single-cell analysis of complex biological phenomena and offers a starting point for the future exploration of the endogenous disease- and agingrelated mechanisms that cause death
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Day, Ngoc Bich. "The inhibition of yeast spoilage of blueberries during modified atmosphere packaging storage." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/27868.

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Modified atmosphere packaging storage combines an atmosphere of higher carbon dioxide and lower oxygen levels than air, with chilling temperatures to extend shelf-life of fresh fruits. In three modified atmosphere packaging storage trials, blueberries were packaged in film bags with different gas permeabilities, and stored at about 4°C. Storage of blueberries in packages of a film with intermediate gas permeability produced an aerobic atmosphere and a relatively low carbon dioxide level, resulting in rapid growth of yeast and molds on blueberries. Packaging blueberries in a film with very low gas permeability created a high carbon dioxide almost anaerobic atmosphere, which successfully inhibited yeast and mold growth on blueberries for up to eight weeks. The possibility of yeast inhibition by antifungal compounds accumulated in blueberries stored under modified atmosphere packaging conditions was investigated by using the disk diffusion assay. The results of these assays showed the absence of antifungal activity against two Rhodotorula species, a Zygosaccharomyces species, a Cryptococcus species, a Debaryomyces species, and indicated that the inhibition of yeast growth was due to low temperature, high carbon dioxide level and anaerobic conditions. The effects of temperature and atmosphere composition were investigated by using natural flora of blueberry juice and two yeast isolates grown in sterilized juice. At 21°C, yeast growth was slow in the presence of carbon dioxide and absence of oxygen. At low temperature, yeast growth was slow in the presence of oxygen, but was inhibited in the anaerobic, high carbon dioxide environment. It is proposed that the micro-aerobic environment of modified atmosphere packaging storage might have allowed slow desaturation of yeast membrane fatty acids which enabled yeasts to maintain membrane fluidity and function at low .temperature. Furthermore, yeast growth during storage of modified atmosphere packaged blueberries may be affected by low temperature and high carbon dioxide conditions.
Land and Food Systems, Faculty of
Graduate
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Cakar, Zeynep Petek Çakar Zeynep Petek. "Metabolic engineering of yeast /." [S.l.] : [s.n.], 2000. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=13665.

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Rodríguez, Porrata Boris alejandro. "Dehydration tolerance in yeast." Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/8678.

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La habilidad de las levaduras de superar la deshidratación y de reactivar su metabolismo después de la rehidratación tiene una importancia en la industria de los alimentos y en la biotecnología. Nosotros hemos dirigido nuestro trabajo a mejorar la viabilidad y vitalidad de las levaduras después de la rehidratación. Se realizaron estudios desde el punto de vista fisiológico de las levaduras durante la optimización de las condiciones de rehidratación y estudios moleculares como la determinación de los genes esenciales de respuesta a Secado y Rehidratación (SR) y la caracterización de la muerte celular a consecuencia del SR. Se sobre expresaron genes que codifican péptidos que permiten superar la viabilidad alcanzada por las levaduras bajo estas condiciones de estrés.
Hipótesis de partida:
Algunos metabolitos y genes esenciales de respuesta a estrés por secado y rehidratación permiten a las levaduras tolerar la desecación
The ability of yeast to overcome dehydration and restart metabolism after rehydration has an importance in the food industry and biotechnology. We have directed our work to improve the viability and vitality of the yeast after rehydration. The studies were conducted in one hand from the physiological point of view to optimize rehydration conditions, and in the other hand from the molecular point of view. We identified the essential genes in response to drying and rehydration and its role in yeast cell death. Moreover we study the effect of over expressed some of this genes on yeast desiccation tolerance.
Hypothesis:
Some metabolites and essential genes in response to stress during drying and rehydration allow yeasts tolerate desiccation.
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Books on the topic "Yeast"

1

Esther, Segal, and Baum Gerald L, eds. Pathogenic yeasts and yeast infections. Boca Raton: CRC Press, 1994.

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Feldmann, Horst, ed. Yeast. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2012. http://dx.doi.org/10.1002/9783527659180.

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Kingsley, Charles. Yeast. Stroud: Alan Sutton, 1994.

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Huxley, Thomas Henry. Yeast. Place of publication not identified]: Dodo Press, 2008.

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Symposium on Yeasts (10th 2000 Papendal, Arnhem, the Netherlands). ISY 2000: The rising power of yeasts in science and industry : Tenth International Symposium on Yeasts : 27 August-1 September 2000, Papendal, Arnhem, the Netherlands : symposium book. Delft, the Netherlands: Delft University Press, 2000.

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Burke, Dan, and Smith Jeffrey S. Yeast genetics: Methods and protocols. New York: Humana Press, 2014.

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Satyanarayana, T. Yeast Biotechnology: Diversity and Applications. Dordrecht: Springer Netherlands, 2009.

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Barnett, James A., and Linda Barnett. Yeast Research. Washington, DC, USA: ASM Press, 2011. http://dx.doi.org/10.1128/9781555817152.

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Evans, Ivor H. Yeast Protocols. New Jersey: Humana Press, 1996. http://dx.doi.org/10.1385/0896033198.

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Xiao, Wei. Yeast Protocols. New Jersey: Humana Press, 2005. http://dx.doi.org/10.1385/1592599583.

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Book chapters on the topic "Yeast"

1

Branduardi, Paola, and Danilo Porro. "Yeasts in Biotechnology." In Yeast, 347–70. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2012. http://dx.doi.org/10.1002/9783527659180.ch14.

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Gaillardin, Claude. "Hemiascomycetous Yeasts." In Yeast, 371–405. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2012. http://dx.doi.org/10.1002/9783527659180.ch15.

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Dujon, Bernard. "Yeast Evolutionary Genomics." In Yeast, 407–19. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2012. http://dx.doi.org/10.1002/9783527659180.ch16.

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González, Aldo. "Yeast." In Encyclopedia of Astrobiology, 1785–86. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-11274-4_1698.

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Rández-Gil, Francisca, Lidia Ballester-Tomás, and José Antonio Prieto. "Yeast." In Bakery Products Science and Technology, 153–74. Chichester, UK: John Wiley & Sons, Ltd, 2014. http://dx.doi.org/10.1002/9781118792001.ch8.

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González, Aldo. "Yeast." In Encyclopedia of Astrobiology, 2661–62. Berlin, Heidelberg: Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-44185-5_1698.

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Servi, Stefano. "Yeast." In Biotechnology, 363–89. Weinheim, Germany: Wiley-VCH Verlag GmbH, 2008. http://dx.doi.org/10.1002/9783527620906.ch8.

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González, Aldo. "Yeast." In Encyclopedia of Astrobiology, 1–2. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-27833-4_1698-2.

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González, Aldo. "Yeast." In Encyclopedia of Astrobiology, 3259–60. Berlin, Heidelberg: Springer Berlin Heidelberg, 2023. http://dx.doi.org/10.1007/978-3-662-65093-6_1698.

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Chiba, Yasunori. "Heterologous Glycoprotein Production (Yeast Yeast )." In Glycoscience: Biology and Medicine, 1537–43. Tokyo: Springer Japan, 2014. http://dx.doi.org/10.1007/978-4-431-54841-6_204.

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Conference papers on the topic "Yeast"

1

Bardhan, Pritam, and Manabendra Mandal. "Rhodotorula mucilaginosa R2: A potent oleaginous yeast isolated from traditional fermented food, as a promising platform for the production of lipid-based biofuels, bioactive compounds and other value added products." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/qbyp3823.

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Oleaginous yeasts may provide an alternative platform for the sustainable production of microbial lipids-derived biodiesel and other health promoting bioactive metabolites such as natural pigments. In this regard, traditional fermented foods are unique and untapped habitats for the isolation and characterization of oleaginous yeasts with beneficial properties. In this study, we analysed the yeast diversity from selected traditional fermented foods of Manipur and Mizoram, India and studied their oleaginous attributes for biodiesel production. 14 potential oleaginous yeasts were isolated using culture-dependent techniques. The isolates were identified by 5.8S internal transcribed spacer (ITS) rRNA gene sequencing. Intracellular triacylglycerides (TAG) accumulation by yeast cells were confirmed by Nile red fluorescence microscopy. Fatty acid methyl esters (FAME) profile of the yeast strains were analysed by GC-MS. The identified yeast isolates belonged to seven different genera viz. Rhodotorula, Pichia, Candida, Saturnispora, Wickerhamomyces, Zygoascus and Saccharomyces. Rhodotorula mucilaginosa R2 exhibited the maximum lipid content (% lipid/g dry cell weight) of (21.63 %) after 96 h of growth in nitrogen-limited medium. R. mucilaginosa R2 single cell oil (RMSCO) was transesterified into biodiesel with a conversion efficiency of 96.6 % using a heterogeneous potassium hydroxide catalyst (K-RAC) supported on R. mucilaginosa R2 deoiled cake activated carbon. The physico-chemical properties of the biodiesel derived from R. mucilaginosa R2 single cell oil were within the limits of ASTM and EN standards. FAME analysis of the transesterified lipid extract suggested the potential use of yeast derived oil as an alternative to vegetable oil for biodiesel production. Furthermore, carotenoids obtained from the pink yeast R. mucilaginosa R2 was composed of torularhodin, torulene and β-carotene and exhibited strong antioxidant activity. Keywords: Oleaginous yeast, Triacylglycerides, Fermented food, Rhodotorula mucilaginosa
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Sun, Jiashu, Deyu Li, Chris Stowers, and Erik Boczko. "Measurement of the Volume Growth Rate of Single Budding Yeast." In ASME 2009 Second International Conference on Micro/Nanoscale Heat and Mass Transfer. ASMEDC, 2009. http://dx.doi.org/10.1115/mnhmt2009-18496.

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We report on measurements of the growth rate of single budding yeasts with two microfluidic devices. One device is a MOSFET-based microfluidic Coulter-type sensor, which amplifies nonlinearly the resistance modulation from the translocation of budding yeast through the sensing microchannel. By moving a budding yeast cell back and forth through the sensing channel and measuring the induced resistance pulse from the translocation of the budding yeast, the volume growth rate of a budding yeast cell can be measured over its whole cell cycle. The other microfluidic device is based on comparing the resistance of the sensing microchannel with that of a reference microchannel, which eliminates the signal drift from the electrical conductivity change of the culture media. The reference channel-based sensing scheme enables real-time measurements of the volume growth rate of a budding yeast cell sitting in the sensing microchannel over a whole cell cycle. Measurement results from both devices show that the volume growth of single budding yeast is of sigmoid shape with a slow growth rate both before the bud emergence and at the end of the cell cycle. The device could be used for other important applications such as sensing the response of kidney cells to their micro-environments.
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Bandhu, Sheetal, and Debashish Ghosh. "Genetic modification to enhance single cell oil production in the oleagineous yeast Rhodotorula mucilaginosa." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/bdpk2930.

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Liquid fuels derived from non-fossil resources are considered feasible alternatives as global fuel demand rises. Yeast single cell oil is gaining ground as feedstock for biofuels and oleochemicals over plant-borne or algal oil due to its short lifespan and invariable quality under different seasonal or geographical conditions. In the present work, oleaginous yeast Rhodotorula mucilaginosa IIPL32 was genetically modified to improve its oil-producing capacity by overexpressing malic enzyme, a reductant providing enzyme active in several oleaginous yeasts. Intracellular Malic enzyme was purified and characterized to validate its presence and determine its involvement in lipid synthesis and NADPH+ supply in the yeast R mucilaginosa. Apart from the pentose phosphate route, it was found that malic enzymes also provided reductants for lipid biosynthesis in this yeast. A linear expression cassette was created for selective integration of the malic enzyme under a strong promoter into the yeast genome. The lipid output was increased 1.18-fold along with significant alteration in its fatty acid profile. Estimating fuel properties revealed that the total monounsaturated fatty acids improved from 49% to 66%. The lipid produced by transformed yeast complies with fuel properties (Density, Viscosity, Cetane number, Cloud point, Pour point) as per the EU, Indian, and US standards. We conclude that genetically modified yeast lipids could be a sustainable alternative to using plant-borne oil in biofuel generation. The yeast's ability to assimilate pentose sugars generated from biomass hydrolysis makes it an efficient oil platform.
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Abdul Razzak, Badia, Rehan Nashwan Abul-Rahman, and Maha Azad Hamid. "Mutation Effect of Chemical Mutagen Ethymthane sulfonate (EMS) on Some Local Yeasts." In The 8th International Conference of Biotechnology, Environment and Engineering Sciences. SRO media, 2020. http://dx.doi.org/10.46617/icbe8002.

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Thirty samples of orange juice were collected from local markets in Mosul / Iraq. Isolates were diagnosed after performing phenotypic, culture and biochemical tests. The results showed that the yeasts belong to the following species: Rhodotorula rubra 36%, Trichosporon asahii 16%, Cryptococcus laurentii 28%, and Candida tropicalis 20%. The susceptibility of isolates to six antibiotics Candizole (Cd), Clotrimazole (Ct), Fluconazole (Fc), Ketoconazole (Kc), Lamisil (Ls), and Nystatin (Nys) was studied. The results of the sensitivity test showed that R. rubra was resistant to all antibiotics used except for Lamisil (Ls). The rest of the yeasts varied among themselves in their resist antibiotics. The chemical mutagen Ethyl Methanesulfate (EMS) at a concentration of 0.2 mg / ml on the vitality of the yeasts showed that the highest effect in the yeast Crypto. laurentii, with the killing severity reaching 4.47% while the lowest effected yeast was Tricho. asahii, with killing severity reaching 72%.
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Gomide, João Victor Boechat, Elton Vieira Cunha, and Guilherme Boechat Gomide. "Automatic Yeast Detection and Counting Using Computer Vision Techniques." In Workshop de Visão Computacional. Sociedade Brasileira de Computação - SBC, 2021. http://dx.doi.org/10.5753/wvc.2021.18884.

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This paper presents the development of a computer vision system that automatically identifies and counts viable and inviable brewer's yeast, to improve the time and accuracy of results obtained compared to the manual expert counting method commonly performed in the brewing industry. The equipment used consists of a digital video camera coupled to an optical microscope, which transmits the captured images, in real time, to the computer. Two approaches were tested and implemented, one taking into account the morphology and color of yeasts, and the other using machine learning. Although there are programs that automatically count yeasts, this is the first application that makes use of convolutional neural network techniques with Yolo to identify yeasts, making the results more accurate and reliable compared to manual methods. Experiments were carried out to measure the performance and accuracy of the prototype, which are presented in this article.
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Sun, N. X., Y. H. Liu, and Y. X. Wang. "Utilization of spent brewer's yeast for selenium-enriched yeast." In The 2015 International Conference on Sustainable Development (ICSD2015). WORLD SCIENTIFIC, 2016. http://dx.doi.org/10.1142/9789814749916_0082.

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Atis, Severine, Bryan T. Weinstein, Andrew W. Murray, and David R. Nelson. "Video: Rocket Yeast." In 73th Annual Meeting of the APS Division of Fluid Dynamics. American Physical Society, 2020. http://dx.doi.org/10.1103/aps.dfd.2020.gfm.v0020.

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Alasmar, Reem Moath, and Samir Jaoua. "Investigation and Biological Control of Toxigenic Fungi and Mycotoxins in Dairy Cattle Feeds." In Qatar University Annual Research Forum & Exhibition. Qatar University Press, 2020. http://dx.doi.org/10.29117/quarfe.2020.0065.

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Mycotoxins, the secondary fungal metabolites are important contaminants of food and feed. Among the other contaminants, aflatoxin B1 (AFB1) and OTA are frequently detected in the animal feed product. In the present study, the mixed dairy cow feed products were collected from the supermarkets in Qatar and analyzed for the presence of AFB1 and OTA. Yeast strains were isolated and tested for their biological control activities against aflatoxigenic and ochratoxin fungi. We demonstrated that local 15 yeasts isolates have important antifungal potential activities through the synthesis of volatile organic compounds (VOC) that are able to act against the mycotoxigenic fungi and their synthesis of the mycotoxins. Two Yeast strains (4&2) isolated from fermented food, have shown a great antifungal inhibition growth in-vitro as well as spores inhibition and mycotoxins synthesis.
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MAMAEV, D. V., A. G. ROGOV, T. N. GOLEVA, and R. A. ZVYAGILSKAYA. "MITOPHAGY IN YEAST CELLS." In HOMO SAPIENS LIBERATUS. TORUS PRESS, 2020. http://dx.doi.org/10.30826/homosapiens-2020-44.

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Gourley, Paul L., Judy K. Hendricks, Anthony E. McDonald, R. Guild Copeland, Robert K. Naviaux, and Michael P. Yaffe. "Biocavity laser spectroscopy of genetically altered yeast cells and isolated yeast mitochondria." In Biomedical Optics 2006, edited by Daniel L. Farkas, Dan V. Nicolau, and Robert C. Leif. SPIE, 2006. http://dx.doi.org/10.1117/12.674187.

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Reports on the topic "Yeast"

1

Kennedy, Brian K. Structural Inheritance in Yeast. Fort Belvoir, VA: Defense Technical Information Center, July 2006. http://dx.doi.org/10.21236/ada456910.

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Kennedy, Brian K., and Daniel Lockshon. Structural Inheritance in Yeast. Fort Belvoir, VA: Defense Technical Information Center, July 2004. http://dx.doi.org/10.21236/ada427876.

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Droby, Samir, Joseph W. Eckert, Shulamit Manulis, and Rajesh K. Mehra. Ecology, Population Dynamics and Genetic Diversity of Epiphytic Yeast Antagonists of Postharvest Diseases of Fruits. United States Department of Agriculture, October 1994. http://dx.doi.org/10.32747/1994.7568777.bard.

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One of the emerging technologies is the use of microbial agents for the control of postharvest diseases of fruits and vegetables. A number of antagonistic microorganisms have been discovered which have the potential to effectively control postharvest diseases. Some of this technology has been patented and commercial products such as AspireTM (Ecogen Corporatin, Langhorne, PA, USA), Biosave 10TM and Biosave 11TM (Ecoscience Inc., Worchester, MA, USA) have been registered for commercial use. The principal investigator of this project was involved in developing the yeast-based biofungicide-AspireTM and testing its efficacy under commercial conditions. This research project was initiated to fill the gap between the knowledge available on development and commercial implementation of yeast biocontrol agents and basic understanding of various aspects related to introducing yeast antagonists to fruit surfaces, along with verification of population genetics. The main objectives of this study were: Study ecology, population dynamics and genetic diversity of the yeast antagonists Candida guilliermondii, C. oleophila, and Debaryomyces hansenii, and study the effect of preharvest application of the yeast antagonist C. oleophila naturally occurring epiphytic microbial population and on the development of postharvest diseases of citrus fruit during storage. Our findings, which were detailed in several publications, have shown that an epiphytic yeast population of grapefruit able to grow under high osmotic conditions and a wide range of temperatures was isolated and characterized for its biocontrol activity against green mold decay caused by Penicillium digitatum. Techniques based on random amplified polymorphic DNA (RAPD) and arbitrary primed polymerase chain reaction (ap-PCR), as well as homologies between sequences of the rDNA internal transcribed spacers (ITS) and 5.8S gene, were used to characterize the composition of the yeast population and to determine the genetic relationship among predominant yeast species. Epiphytic yeasts exhibiting the highest biocontrol activity against P. digitatum on grapefruit were identified as Candida guilliermondii, C. oleophila, C. sake, and Debaryomyces hansenii, while C. guilliermondii was the most predominant species. RAPD and ap-PCR analysis of the osmotolerant yeast population showed two different, major groups. The sequences of the ITS regions and the 5.8S gene of the yeast isolates, previously identified as belonging to different species, were found to be identical. Following the need to develop a genetically marked strain of the yeast C. oleophila, to be used in population dynamics studies, a transformation system for the yeast was developed. Histidine auxotrophy of C. oloephila produced using ethyl methanesulfonate were transformed with plasmids containing HIS3, HIS4 and HIS5 genes from Saccharomyces cerevisiae. In one mutant histidin auxotrophy was complemented by the HIS5 gene of S. cerevisiae is functionally homologous to the HIS5 gene in V. oleophila. Southern blot analysis showed that the plasmid containing the S. cerevisiae HIS5 gene was integrated at a different location every C. oleophila HIS+ transformant. There were no detectable physiological differences between C. oleophila strain I-182 and the transformants. The biological control ability of C. oleophila was not affected by the transformation. A genetically marked (with b-glucuronidase gene) transformant of C. oleophila colonized wounds on orange fruits and its population increased under field conditions. Effect of preharvest application of the yeast C. oleophila on population dynamics of epiphytic microbial population on wounded and unwounded grapefruit surface in the orchard and after harvest was also studied. In addition, the effect of preharvest application of the yeast C. oleophila on the development of postharvest decay was evaluated. Population studies conducted in the orchard showed that in control, non-treated fruit, colonization of wounded and unwounded grapefruit surface by naturally occurring filamentous fungi did not vary throughout the incubation period on the tree. On the other hand, colonization of intact and wounded fruit surface by naturally occurring yeasts was different. Yeasts colonized wounded surface rapidly and increased in numbers to about two orders of magnitude as compared to unwounded surface. On fruit treated with the yeast and kept on the tree, a different picture of fungal and yeast population had emerged. The detected fungal population on the yeast-treated intact surface was dramatically reduced and in treated wounds no fungi was detected. Yeast population on intact surface was relatively high immediately after the application of AspireTM and decreased to than 70% of that detected initially. In wounds, yeast population increased from 2.5 x 104 to about 4x106 after 72 hours of incubation at 20oC. Results of tests conducted to evaluate the effect of preharvest application of AspireTM on the development of postharvest decay indicated the validity of the approach.
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Stern, David F. Mammalian Homologs of Yeast Checkpoint Genes. Fort Belvoir, VA: Defense Technical Information Center, July 2001. http://dx.doi.org/10.21236/ada404591.

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Stern, David. Mammalian Homologs of Yeast Checkpoint Genes. Fort Belvoir, VA: Defense Technical Information Center, July 2000. http://dx.doi.org/10.21236/ada393426.

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Stern, David F. Mammalian Homologs of Yeast Checkpoint Genes. Fort Belvoir, VA: Defense Technical Information Center, July 1999. http://dx.doi.org/10.21236/ada384149.

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Harris, David A. Propagation of Mammalian Prions in Yeast. Fort Belvoir, VA: Defense Technical Information Center, July 2006. http://dx.doi.org/10.21236/ada472675.

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Friddle, R. W., J. E. Klare, A. Noy, M. Corzett, R. Balhorn, R. J. Baskin, S. S. Martin, and E. P. Baldwin. DNA Compaction by Yeast Mitochondrial Protein ABF2p. Office of Scientific and Technical Information (OSTI), May 2003. http://dx.doi.org/10.2172/15007313.

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Teng, Shu-chun. Identification of Protein Components of Yeast Telomerase. Fort Belvoir, VA: Defense Technical Information Center, September 2000. http://dx.doi.org/10.21236/ada392301.

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Teng, Shu-Chun. Identification of Protein Components of Yeast Telomerase. Fort Belvoir, VA: Defense Technical Information Center, September 1999. http://dx.doi.org/10.21236/ada382853.

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