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H J Tyrrell

Publications and source records attributed to H J Tyrrell.

4 recordsLinked to original sources

Characterisation and metabolic studies of Saccharomyces cerevisiae and Kluyveromyces fragilis by flow microcalorimetry.

The use of microcalorimetry in the routine identification of microorganisms is critically discussed and assessed. By use of flow microcalorimetric studies on Saccharomyces cerevisiae and Kluyveromyces fragilis the role of physical parameters and that of oxygen tension are discussed. The conclusion reached is that identification of microorganisms by microcalorimetry and subsequent discussion of metabolic events revealed by the thermogram, except under restrictive conditions, is inappropriate. However flow microcalorimetry, in contrast to batch microcalorimetry which has been used in the published material on microorganism identification, may allow characterization of yeasts suitable for particular industrial processes.

Ascomycota

Flow microcalorimetric investigation of yeast growth in a complex medium.

The growth of Kluyveromyces fragilis in a complex medium under anaerobic and aerobic growth conditions has been conducted using a flow microcalorimeter. Growth under defined conditions is characterized by an initial exponential rise in heat output rate to a maximum, followed by a decline to a baseline deflection. Inadequate oxygenation can result in a more structured thermogram. The results are used to illustrate the deficiencies of some calorimetric incubations, and observations reported by other authors are critically discussed.

Aerobiosis