Breeding On Cellulose-degradation Bacteria In The Rumen Of Camel

Cellulose is one of the most abundant natural renewable polymer resource in the world. So researches on degradation of cellulose with bio-enzyme have been becoming more and more popular in many countries. Microorganisms with high enzyme activity in rumen are paid particular attention for their special activity of degradation mechanism on cellulose. Therefore to breed dominant strain in rumen can effectively help ruminants make good use of crude fibers.The selected bacteria in this study were isolated from camel rumens in Inner Mongolia. Medium with straw as the sole carbon source was used in the screening procedure and the cellulose Congo red differential medium was used in the re-screening procedure.Then the isolates were enriched and pourplate cultured with cellobiose liquid medium and solid medium. The strains with similar phenotypic characteristics were summarized according to the colony and cell morphology and11strains were selected. The selected isolates were further bred and3inferior strains were eliminated. The remaining eight strains were tested by ability to decomposite crude fiber and secrete exoenzyme and endoenzyme of cellulase. Excluding of experimental error and other uncertainties, selected isolates1#and2#with high fiber decomposition capability and8#and17#with high activity of exoenzymes cellulase were selected from all these eight isolates as dominant strains. In addition, the dominant strains were tested with biochemical and molecular biological identification using classical microbiological identification methods for breeding and the isolate15#was used as control.Results show that:firstly, the majority of the cellulose degrading bacteria isolated from the camel rumen were bacilli, most of which were facultative anaerobe bacteria except one strictly anaerobic bacteria. Perhaps, the cellulose degrading bacteria in camel rumen were mainly facultative anaerobe bacteria. Secondly, the ability of bacilli to decompose crude fiber was higher than coccobacteria. Thirdly, the activity of cellulase exoenzyme of isolates8#and17#was higher than the others. Last, the five cellulose degrading bacteria were1#Rummeliibacillus stabekisii,2#klebsiella oxytoca,8#Kerstersia gyiorum,15#Proteus mirabilis and17#Bordetella sp.,four of which were Proteobacteria, and one was Firmicutes. It was primarily estimated that Proteobacteria was one of the dominant cellulose degrading bacteria in camel rumen.