Premium
Effect of Binary Combinations of Selected Toxic Compounds on Growth and Fermentation of Kluyveromyces marxianus
Author(s) -
Oliva Jose M.,
Ballesteros Ignacio,
Negro M. José,
Manzanares Paloma,
Cabañas Araceli,
Ballesteros Mercedes
Publication year - 2004
Publication title -
biotechnology progress
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.572
H-Index - 129
eISSN - 1520-6033
pISSN - 8756-7938
DOI - 10.1021/bp034317p
Subject(s) - kluyveromyces marxianus , chemistry , vanillin , furfural , catechol , fermentation , yeast , food science , ethanol , biochemistry , organic chemistry , saccharomyces cerevisiae , catalysis
Abstract The inhibitory effects of various lignocellulose degradation products on glucose fermentation by the thermotolerant yeast Kluyveromyces marxianus were studied in batch cultures. The toxicity of the aromatic alcohol catechol and two aromatic aldehydes (4‐hydroxybenzaldehyde and vanillin) was investigated in binary combinations. The aldehyde furfural that usually is present in relatively high concentration in hydrolyzates from pentose degradation was also tested. Experiments were conducted by combining agents at concentrations that individually caused 25% inhibition of growth. Compared to the relative toxicity of the individual compounds, combinations of furfural with catechol and 4‐hydroxybenzaldehyde were additive (50% inhibition of growth). The other binary combinations assayed (catechol with 4‐hydroxybenzaldehyde, and vanillin with catechol, furfural, or 4‐hydroxybenzaldehyde) showed synergistic effect on toxicity and caused a 60–90% decrease in cell mass production. The presence of aldehydes in the fermentation medium strongly inhibited cell growth and ethanol production. Kluyveromyces marxianus reduces aldehydes to their corresponding alcohols to mitigate the toxicity of these compounds. The total reduction of aldehydes was needed to start ethanol production. Vanillin, in binary combination, was dramatically toxic and was the only compound for which inhibition could not be overcome by yeast strain assimilation, causing a 90% reduction in both cell growth and fermentation.