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1.
Candida lipolytica YB 423-12 is able to incorporate fatty acid from the culture medium when lipids are used as carbon substrate. The composition of cell lipids is largely dependent on that of the culture medium. An important 9 desaturase activity acts on incorporated palmitic and stearic acids; and 11-eicosenoic and erucic acids are shortened to oleic acid. 相似文献
2.
Intergeneric hybrids of Saccharomyces cerevisiae and Zygosaccharomyces fermentati obtained by protoplast fusion 总被引:1,自引:0,他引:1
To obtain strains that are able to efficiently produce ethanol from different carbohydrates, mainly cellulose hydrolysates, several species of the genus Candida and a Zygosaccharomyces fermentati strain were examined for their ability to utilize cellobiose and produce ethanol, as well as for their thermotolerance and the possibility of genetic manipulation. Candida obtusa and Zygosaccharomyces fermentati tolerated the maximal temperature for growth, possessed the highest cellobiase activity, and offered the possibility of genetic manipulation, although neither of them proved to be a good producer of ethanol. Intergeneric hybrids of Saccharomyces cerevisiae and Z. fermentati were obtained after protoplast fusion. They were selected as prototrophic strains, after isolation of auxotrophic mutants from Z. fermentati and fusion with an S. cerevisiae strain which was also auxotrophic. The hybrids, which appeared at a frequency of 2 X 10(-7), presented characteristics of both parents, such as resistance to certain drugs and the ability to grow with either cellobiose or lactic acid as the sole carbon source; they were very stable, even under nonselective conditions. These hybrids may have important industrial applications as good fermenting strains. 相似文献
3.
J. M. Muderhwa R. Ratomahenina M. Pina J. Graille P. Galzy 《Applied microbiology and biotechnology》1986,23(5):348-354
Summary The Rhodotorula pilimanae CBS 5804 strain secretes into the culture medium two lipases: their pH optima are 4 and 7. The two lipases were purified by precipitation with acetone followed by chromatography on SP-Sephadex C50 and Sephadex G200. The purification factors achieved in comparison with the supernatant culture were x74 for lipase I and x90 for lipase II. The molecular weights were estimated at 172,800 and 21,400 for lipase I and lipase II, respectively. Their activities are optimal between 45°C and 55°C. The activation energies were 5.9 kcal·mole-1 for lipase I and 12.4 kcal·mole-1 for lipase II. The inactivation energies were about 21.9 and 17.7 kcal·mole-1 for lipase I and lipase II, respectively. The enzymes are slightly inhibited by Cu2+, Co2+, Hg2+, Mn2+, N-acetylacetone, acetic acid and sodium lauryl sulphate. EDTA did not affect their enzymatic activity. These two lipases are secreted in the culture media in the absence of inducer; their biosynthesis is not inhibited by glucose. These lipases hydrolyse primarily the 1-(or 3-)position of all triglycerides tested. 相似文献
4.
By bringing lactose into contact with octanol in the presence of -galactosidase and almond meal with a -glucosidase activity, it is possible to simultaneously synthesize the octylglycosides corresponding to the two hexoses of the disaccharide. The reaction is optimized using an experimental plan. 相似文献
5.
J A Pina 《Acta anatomica》1975,92(1):145-159
The way in which the anterior cardiac veins end in the right atrium is very inconstant; separate opening is very rare and course and situation also changes a lot. We found the vein of Galen in about 90.59% of the cases and its ending differs from the usual. We found the anterior ventricular veins in about 91.45% of the cases; there is only one such vein in 57.00% of the cases, two in 33.64% and three in 9.34%; their origin and opening vary greatly. We saw the vein of Cruveilher in 68.37% of the cases, a lower percentage than that found by other authors. It also differs in its origin, course and opening. The vein of Zuckerkandl was found in 47.00% of the cases, lesser percentage than that found by other authors. The common canal is very important and very frequent in our cases. It opens into the right atrium by one orifice in 27.68% of the cases, by two in 63.93% and by three in 8.19%. 相似文献
6.
Ana Luiza Menegatti Pavan Maria Eugênia Dela Rosa Guilherme Giacomini Fernando Antonio Bacchim Neto Seizo Yamashita Luiz Carlos Vulcano Sergio Barbosa Duarte José Ricardo de Arruda Miranda Diana Rodrigues de Pina 《PloS one》2016,11(4)
Digital radiographic imaging is increasing in veterinary practice. The use of radiation demands responsibility to maintain high image quality. Low doses are necessary because workers are requested to restrain the animal. Optimizing digital systems is necessary to avoid unnecessary exposure, causing the phenomenon known as dose creep. Homogeneous phantoms are widely used to optimize image quality and dose. We developed an automatic computational methodology to classify and quantify tissues (i.e., lung tissue, adipose tissue, muscle tissue, and bone) in canine chest computed tomography exams. The thickness of each tissue was converted to simulator materials (i.e., Lucite, aluminum, and air). Dogs were separated into groups of 20 animals each according to weight. Mean weights were 6.5 ± 2.0 kg, 15.0 ± 5.0 kg, 32.0 ± 5.5 kg, and 50.0 ± 12.0 kg, for the small, medium, large, and giant groups, respectively. The one-way analysis of variance revealed significant differences in all simulator material thicknesses (p < 0.05) quantified between groups. As a result, four phantoms were constructed for dorsoventral and lateral views. In conclusion, the present methodology allows the development of phantoms of the canine chest and possibly other body regions and/or animals. The proposed phantom is a practical tool that may be employed in future work to optimize veterinary X-ray procedures. 相似文献
7.
Naidu S. Chowdari Chin Pan Chetana Rao David R. Langley Prasanna Sivaprakasam Bilal Sufi Daniel Derwin Yichong Wang Eilene Kwok David Passmore Vangipuram S. Rangan Shrikant Deshpande Pina Cardarelli Gregory Vite Sanjeev Gangwar 《Bioorganic & medicinal chemistry letters》2019,29(3):466-470
Uncialamycin analogs were evaluated as potential cytotoxic agents in an antibody-drug conjugate (ADC) approach to treating human cancer. These analogs were synthesized using Hauser annulations of substituted phthalides as a key step. A highly potent uncialamycin analog 3c with a valine-citrulline dipeptide linker was conjugated to an anti-mesothelin monoclonal antibody (mAb) through lysines to generate a meso-13 conjugate. This conjugate demonstrated subnanomolar potency (IC50?=?0.88?nM, H226 cell line) in in vitro cytotoxicity experiments with good immunological specificity to mesothelin-positive lung cancer cell lines. The potency and mechanism of action of this uncialamycin class of enediyne antitumor antibiotics make them attractive payloads in ADC-based cancer therapy. 相似文献
8.
F. Servat D. Montet M. Pina N. Bernet A. Arnaud P. Galzy H. Ledon L. Marcou J. Graille 《Biotechnology letters》1990,12(9):689-692
Summary Oleylhydroxamic acid (Oleyl HA) was produced by acylation of neutralized hydroxylamine with oleic acid in buffered or in solvent media using the broad-spectrum amidase activity ofBrevibacterium (BB) sp 19 cells. 相似文献
9.
10.
J. M. Laborbe Carole Dwek R. Ratomahenina M. Pina J. Graille P. Galzy 《World journal of microbiology & biotechnology》1989,5(4):517-523
Summary The possibility of growingCandida rugosa on palm oil to produce single-cell protein was studied. Optimal conditions were a pH of 4, T=34°C and with up to 10 g feedstock/l. Batch growth was sometimes showed diauxic. A growth yield of 0.8 g dry cells/g feedstock added and an efficiency close to 1 g dry cells/g feedstock used were obtained in batch. Continuous cultivation yielded between 0.8 and 1.0 g yeast dry cells/litre reactor/h depending upon the mean residence time. The lipid, amino acid, mineral and nucleic acid content of the produced yeast was determined.
Production de protéine uni-cellulaire à partir d'huile de palme en utilisantCandida rugosa
Résumé La possibilité de faire croîtreC. rugosa sur huile de palme est étudiée en vue de la production de protéines uni-cellulaires. Les conditions environnementales optimum trouvées par l'expérimentation, sont les suivantes: pH=4, T=34°C, et jusqu'à 10 g/l de substrat. La croissance en batch révèle parfois le phénomène de diauxie. On obtient un rendement de croissance de 0,8 g de cellules sèches par g de substrat ajouté et une efficacité proche de 1 g de cellules sèches par g de substrat consommé. En culture continue, on obtient entre 0,8 et 1,0 g de cellules levuriennes sèches par litre de volume de réacteur et par heure. On a déterminé le contenu en lipides, acides aminés, matières minérales et acides nucléiques des levures produites.相似文献