In this work the compound obtained from yeast culture extract (YCE) that stimulated the activity of an anaerobic cellulolytic consortium (ACC) was characterized. YCE were obtained at different pH (4, 7 and 10) and ultra-filtered 300 and 30 kDa membranes (UYE). The 30 kDa UYE was heated to 60 °C, 90 °C and 120 °C and gel filtered (GYF). Mid infrared spectroscopy, protein and carbohydrate analysis of GYF were conducted. Results showed that YCE, UYE and GYF significantly stimulated (p < 0.05) the biomass production, acetate concentration and carboxymethyl cellulase activity of the ACC, in relation to the control. The GYF had an estimated molecular mass of 4 kDa. Mid-infrared and biochemical analysis of GYF suggested that the active compound is a peptide.
© 2010 Blackwell Verlag GmbH.