Isolation and identification of a cellulolytic Enterobacter from rumen of Aceh cattle

Aims The aim of this study was to isolate and identify a cellulolytic bacterium from the rumen fluid of Aceh's cattle. Biodegradation by cellulolytic rumen bacteria can be used as a source of cellulolytic bacteria that act to degrade feed fibrous material so as to improve the quality of nutrients and digestibility of feed ingredients at a cheaper price than the use of commercial cellulase enzymes. Materials and Methods Samples were collected from rumen fluid of Aceh's cattle in Abattoirs (RPH) of Banda Aceh city, Indonesia, isolation, and screening of cellulolytic bacteria were done in Microbiology Laboratory, Faculty of Veterinary Medicine, Syiah Kuala University, Banda Aceh, Indonesia. Results The S1 isolates showed ±2.5 cm of clear zone diameter. Microscopically, this strain was found to be a Gram-negative, Bacillus. Homology and phylogenetic tree analysis of 16S rRNA showed that S1 isolate has 91% of sequence similarity with that of Enterobacter cloacae. 91% sequence homology shown in this study proved that the S1 isolate is probably either a new species or another genus of Enterobacteriaceae. Conclusion Current study suggests that cellulose hydrolytic bacteria isolated from rumen fluid of Aceh cattle on Bushnell Haas medium-carboxymethylcellulose agar, and some potent cellulose degrading bacteria have been identified.