Abstract:

The levoglucosan-assimilating and ethanol-producing microorganisms were screened using 1,6-anhydro-β-D-glucopyranose (levoglucosan) of cellulosic pyrolysis products as a sole carbon source from 89 strains of microorganisms (mostly producing ethanol) and 319 soil samples, respectively. 2 strains of yeasts (Sporobolomyces 1 and Rhodotorula 1) and 6 strains of moulds (Rhizopus 4 and Monascus 2) had weak levoglucosan-assimilating ability in 89 strains of microorganisms. 70 strains of yeasts and 10 strains of bacteria were isolated from the 319 soil samples. In all isolated microorganisms, the strain of No. Y215 showed the strongest levoglucosan-assimilating ability. After it was cultured for three days, the utilization rate of 2% levoglucosan was up to 64.12%. This strain was classified as Lipomyces starkeyi according to a taxonomic identification. Among all tested microorganisms, no microorganisms could ferment levoglucosan to ethanol. The results gave microbial strains for constructing recombinant strains to ferment levoglucosan to ethanol.