Experimental investigation of the bound dissipation function

Abstract

By means of a microcalorimeter (direct calorimetry) and a Warburg-apparatus (indirect calorimetry) that part of the dissipation of a growing culture of yeast cells which remains irreversible in the cells is determined (psi u). The course of the psi u-function with time correlates with the increase of the specific cell concentration being conditioned by the growth phase of the culture but similar for fermentative and respirative metabolism.

Microcalorimetric investigations of the metabolism of yeasts VII. Flow-calorimetry of aerobic batch cultures

“…Under these optimal conditions a bi-or triphasic growth occurs (Brettel, 1974;Schaarschmidt et al, 1975) if glucose is the sole energy and carbon source (Figs. 2 and 3b).…”

A hierarchical framework for the analysis of scale

“…Schaarschmidt et al (1975) measured the bound dissipation function, Du, as the difference between the heat production due to metabolic activity and the heat production actualy leaving the system. In a subsequent paper, Schaarschmidt et al (1977) argued that a semilogarithmic relationship should exist between heat production and biomass, a prediction which was confirmed by several studies.…”

The growth and development of living organisms from the thermodynamic point of view

“…A positive correlation between the specific growth rate and ψ u also has been noted for representatives of different taxons: bacteria Serratta marinorubta, S. mercescens [27], yeast Sacharamyces cerevisiae [24], larvae of mealworm beetle Tenebrio molitor [25], larvae of house crickets Acheta domestica, embryos of sand lizard Lacerta agilis, chicken embryos Gallus domesticus [28], juvenile fishes Xiphophorus helleri [23], larvae of axolotl Ambystoma mexicanum [26], ovogenesis of clawed frogs Xenopus laevis [5]. It is important to have a look at the time dependence of the quantity ψ u at the growth of the organisms: it gives an additional way of assessment of adequacy of the equation (7).…”

“…We can draw certain conclusions from the results. It has appeared, that during an essential period of ontogenesis of organisms, the values of incoming and outgoing energy fluxes practically coincide, Figure 1 The dependence of specific growth rate on ψ u -function Species: a -yeast Saccharomyces cerevisiae (according to Schaarschmidt et al [24]; b -larvae of crickets Acheta domestica; c -embryos of lizards Lacerta agilis; dchicken embryos Gallus domesticus (according to Kleymenov [28]). The dependences are approximated by straight lines, according to equation (7).…”

“…At early stages of the growth in ontogenesis, the distinction of results of the direct and indirect calorimetry ψ u is great enough to address to an assessment of the adequacy of equation (7). Species: a -yeast Saccharomyces cerevisiae (according to Schaarschmidt et al [24]); b -larvae of crickets Acheta domestica; c -embryos of lizards Lacerta agilis; d -chicken embryos Gallus domesticus (according to Kleymenov [28]). The dependences are approximated by curve lines, according to equation (11).…”