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Selection of Wine Yeasts for Growth and Fermentation in the Presence of Ethanol and Sucrose 总被引:5,自引:3,他引:2 下载免费PDF全文
Tahía Benítez Lucas del Castillo Andrs Aguilera Jaime Conde E. Cerdolmedo 《Applied microbiology》1983,45(5):1429-1436
To optimize the conversion of carbohydrates to ethanol, strains of several Saccharomyces species were examined for the ability to grow and ferment in a range of sucrose and ethanol concentrations. A total of 632 wine yeasts, most of them isolated from wineries in Andalusia and Extremadura, southwestern Spain, were subjected to screening and selection. Growth and fermentative capacity in different ethanol and sucrose concentrations varied from one strain to another. There was no correlation between growth and fermentative capacity. The best 35 strains grew in 15% ethanol and fermented in 18% ethanol. Ethanol accumulated, although at a reduced rate, after the cells stopped growing. Most yeast strains were highly fermentative in 50% sucrose. Some of them effectively utilized the carbohydrates of the culture, yielding final ethanol concentrations of > 14%. Of the 35 selected strains, 16 were promising for genetic analysis and breeding because of their capacity to sporulate. These strains were homothallic, and their spores were viable. The meiotic products analyzed so far were also homothallic. 相似文献
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The effect of the Abortion Act on gynaecological work in one provincial teaching hospital is that despite an increase in patient turnover of 45% the waiting list has increased by 200%. It is suggested that the Act has had little effect on the birth rate or illegitimacy and that there may have been an increase in criminal abortion. 相似文献
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The antibiotic activity of the antifungal substance mucidin was compared with the activity of nystatin and pimaricin. The antibiotics were tested by the plate method using 19 fungal species, mainly phytopathogenic ones. Toward 14 species, mucidin was ten times more active than nystatin and pimaricin, toward 5 species the activities were roughly the same. The antibiotics differed also in the sharpness of the inhibition zone boundaries. 相似文献
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Brian Snoad 《Genetica》1966,37(1):247-254
By appropriate genetical studies using reciprocal translocation stocks it has been possible to confirmLamprecht's evidence that inPisum there are seven linkage groups.
Lamm's evidence for six linkage groups has been shown to be due to incomplete knowledge of the chromosomal structure of certain interchange lines.It is suggested thatLamprecht's system of chromosomal nomenclature should be universally adopted forPisum.Lamm &Miravelle's extended tester set has been accordingly renumbered and the intercrossing of the interchange lines completed in order to extend the confirmatory evidence as to their chromosomal constitution. 相似文献
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