Enumeration and characterization of cellulolytic bacteria from refuse of alandfill

Enumeration and phenotypic characterization of aerobic cellulolytic bacteri a were performed on fresh. 1 year old and 5 years old refuse samples of a F rench landfill site. Numbers of cellulolytic bacteria ranged From 1.1 x 10( 6) to 2.3 x 10(8) c.f.u. (g dry wt.)(-1) and were lower in 5 years old refu se samples. A numerical analysis of phenotypic data based on 80 biochemical tests and per-formed on 321 Gram-positive isolates fi om refuse, revealed a high phenotypic diversity of cellulolytic bacteria which were distributed into 21 clusters. Based on the phenotypic analysis and the sequencing of 1 6S rDNA of five representative strains of major clusters, the predominant c ellulolytic groups could be assigned to the family of Bacillaceae and to th e genera Cellulomonas,Microbacterium and Lactobacillus. Furthermore, chemic al parameters such as pH, carbohydrates and volatile solid contents influen ced the composition of the cellulolytic bacterial groups which were reduced essentially to the family of Bacillaceae in the oldest refuse samples. (C) 2001 Federation of European Microbiological Societies. Published by Elsevi er Science B.V. All rights reserved.