About this Journal Submit a Manuscript Table of Contents
ISRN Microbiology
Volume 2012 (2012), Article ID 650563, 9 pages
http://dx.doi.org/10.5402/2012/650563
Research Article

Isolation of Cellulolytic Bacillus subtilis Strains from Agricultural Environments

1Division of Sustainable Agriculture Research, Jeju Agricultural Research and Extension Services, Jeju-do 697-828, Republic of Korea
2Research Division, Bio-Agr Co. Ltd., Jeju-shi, Jeju-do 690-022, Republic of Korea
3Department of Food Bioengineering, Jeju National University, Jeju-do 690-756, Republic of Korea

Received 4 October 2011; Accepted 20 November 2011

Academic Editors: M. Feiss and M. T. Rowe

Copyright © 2012 Yu-Kyoung Kim et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The bioconversion of cellulose and hemicellulose to soluble sugars is important for global stabilization and a sustainable human society. Here, hundreds of cellulolytic bacteria were screened and isolated from soil, compost, and animal waste slurry in Jeju Island, South Korea. Among the isolates, three strains, SL9-9, C5-16, and S52-2, showing higher potential for practical uses were purified on carboxymethyl cellulose (CMC) agar plates and identified as Bacillus subtilis strains by morphological, physiological, and biochemical characterization and 16S rRNA gene analysis. The production patterns of cellulose or hemicellulose-degrading enzymes were investigated during cell culture. All three isolated strains produced CMCase, Avicelase, β-glucosidase, and xylanase enzymes, which suggested synergic cellulolytic systems in Bacillus subtilis. The enzymes showing CMCase, Avicelase, and xylanase activities existed in cell-free culture supernatant, meanwhile β-glucosidase activity was detected in cell debris suggesting that three of the enzymes, including CMCase, Avicelase, and xylanase, were extracellular, and β-glucosidase was cell membrane bound. The three isolates, SL9-9, C5-16, and S52-2, were not the same strains, presenting slight differences in biochemical characteristics, 16S rRNA gene sequences, and cellulolytic enzyme activities.