Premium
ADSORPTION OF SILICONE ANTIFOAM BY SACCHAROMYCES CEREVISIAE
Author(s) -
Ver P. S.,
Rose A. H.
Publication year - 1976
Publication title -
journal of the institute of brewing
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.523
H-Index - 51
eISSN - 2050-0416
pISSN - 0046-9750
DOI - 10.1002/j.2050-0416.1975.tb06958.x
Subject(s) - incubation , chemistry , adsorption , saccharomyces cerevisiae , chromatography , urea , silicone , emulsion , yeast , biochemistry , organic chemistry
Polydimethylsiloxane (PDS) dispersed in an aqueous emulsion containing stearate emulsifiers and cellulose‐based thickeners is adsorbed to the walls of Saccharomyces cerevisiae NCYC 366 during growth in a defined medium. Including PDS at concentrations up to 30 μg per ml of medium has no effect on the duration of the lag phase or the rate of exponential growth. Cells suspended in buffer containing PDS take at least 2–4 h to become saturated with PDS. Cells saturated with PDS do not differ from PDS‐free organisms in respiratory activity, but have a slightly lower electrophoretic mobility at pH values between 4.0 and 7.0. About half of the PDS on saturated cells appears in the supernatant when they are converted into sphaeroplasts, but proportionately less PDS is released into the supernatant from cells containing less PDS. The equilibrium constant for binding of PDS to isolated walls is about five times as great as for binding to cells. PDS is taken up by isolated walls faster than by intact organisms. Incubation of walls saturated with PDS in buffered EDTA leads to release of PDS from the walls, but incubation in the presence of 8‐ m urea does not.