Phenotypic Detection of Cellulose Hydrolysing Bacteria from the Rumen of Cow and Goat in Bauchi Metropolis

Abstract

Background of Study: Rumen microorganisms are involved in the fermentation of substrates contained in the diet of the animals. Research on the isolation and identification of cellulase enzyme-producing bacteria is still widespread. Biodegradation by cellulolytic bacteria found in rumen can be used as a source of cellulolytic bacteria which will function to degrade fibrous feed material so as to increase quality of nutrition and digestibility of ingredients at a cheaper price than the use of commercial cellulase production. Aim: To isolate and characterize bacteria from animals’ rumen for their ability to hydrolyze cellulose. Place and Duration of Study: Conducted at the Microbiology Laboratory of Abubakar Tafawa Balewa University Bauchi, Bauchi state, Nigeria, between April to July, 2021. Methods: Rumen of cows and goats was sliced and randomly swabbed with a swab stick. They were then inoculated on Nutrient and MacConkey agar media. The plates were then incubated aerobically and anaerobically for 24 hours at 37oC. The resulting colonies that developed after the incubation period was purified and maintained on agar slants for further characterization. Pure isolates were then sub-cultured on carboxymethyl cellulose (CMC) plates and then incubated aerobically and anaerobically for seven days to test their ability to hydrolyze cellulose which was indicated by the appearance of clear zones around the colonies of the organisms. Secreted cellulase by the bacteria was further observed by colouring of the medium using Congo-red 0.3%. Results: A total of 95 bacterial species isolated and characterized from rumen of cow and goat to test their ability to hydrolyze cellulose out of which 52 hydrolyzed celluloses after growing them on cellulose as seen by zone of clearance around the isolates. The isolates include Bacillus subtilis (28.8%), Bacillus licheniformis (27.0%), Yersinia enterocolitica (9.6%), Micrococcus sp. (5.8%), Salmonella sp. (11.5%), Pseudomonas sp. (3.8%) and Streptococcus sp. (13.5%).  Conclusion: This study demonstrates the potentiality of local strains of bacteria isolated from ruminants to hydrolyze cellulose. Proofs based on zone of clearance in cellulose led to the conclusion that the rumen of ruminants contains various microorganisms that can breakdown cellulose.