EFFECT OF COMPONENTS OF ACID-HYDROLYZED HARDWOOD ON CONVERSION OF D-XYLOSE TO 2,3-BUTANEDIOL BY KLEBSIELLA-PNEUMONIAE

The effects of selected components of acid-hydrolysed hardwood (hydrolysate) on growth, sugar utilization, and 2,3-butanediol (BDO) production by a strain of Klebsiella pneumoniae isolated from cellulosic waste were investigated. Acetate, sulfate, furfural, and phenolic compounds were evaluated as potential microbial inhibitors commonly present in hydrolysate. Depending on the inoculation level, yields of BDO were stimulated by acetate levels up to 1.6% (w/v). Sulfate levels up to 0.2% (w/v) did not affect growth, but reduced the BDO yield by approximately 30%. Similar growth results were obtained with furfural concentrations up to 0.2% (w/v), but BDO yields were slightly higher. Phenolic compounds (syringealdehyde and vanillin) were the most growth inhibitory of the potential inhibitors evaluated. Growth was inhibited by concentrations of 0.10% (w/v), while concentrations as low as 0.05% (w/v) inhibited BDO production.