Greener Journal of Biological Sciences

Excellence and Timeliness

  
  

Choose Language

Social


Greener Journal of  Biological Sciences Vol. 3 (2), pp. 061-073, February 2013.

 © 2011 Greener Journals

Research Paper

Manuscript Number:013113421

 

Thermostable Alpha-Amylase from Geothermal Sites of Ethiopia (Afar Region): Isolation, Purification and Characterization

 

1Aynadis Tamene Hailemariam, 2Tilahun Bekele Gezmu and 3*Gulelat Desse Haki

 

1,2Center for Food Science and Nutrition, POBox 1176, Addis Ababa University, Addis Ababa, Ethiopia.

3* Department of Food Science and Technology, University of Botswana, Botswana College of Agriculture, Private Bag 0027,   Gaborone, Botswana.

 

3*Corresponding Author’s Email: gulelatw @ yahoo.com or hgulelat @bca .bw,

Tel: +26774925819


Abstract:

One thousand six hundred and thirty bacterial colonies were isolated from hot springs of Afar region (Ethiopia). Of all the species tested, two bacterial strains designated as AGMSB1 and AGLSB5 were selected and produced the highest level of enzyme with an optimum growth temperature of 55OC and 45OC, respectively. They were identified as rod shaped gram positive bacteria belonging to Bacillus species. The optimum temperature of alpha-amylase produced by AGMSB1 was found to be in the range of 75OC to 95OC with 0.85 U/ml activity at 85OC. The optimum pH was in the range of 5 to 7. The enzyme maintained 78% of its original activity (0.66U/ml) after 60 minutes of incubation at 85OC with more or less stable pH values of 5 to 9. Zn+2 strongly inhibited its activity but it was calcium independent. The optimum temperature of the enzyme produced by AGLSB5 was found to be between 65OC and 85OC with 1.96 U/ml activity at 75OC. The optimum pH was in the range of 5 to 7. The enzyme maintained 60% of its original activity (1.18U/ml) after 50 minutes of incubation at 85OC and it was stable at pH values of 5 to 9. Its activity decreased significantly by the presence of Zn+2 but it was independent of calcium ion.

Keywords: Ethiopia, Afar, Alpha amylase, Hot springs

Return to Content      View Reprint (PDF) (553KB)


Call for Papers/Books/Thesis

Call for Scholarly Articles


Authors from around the world are invited to send scholary articles that suits the scope of this journal. The journal is currently open to submissions and will process and publish articles monthly in two yearly issues.


The journal is centered on quality and goes about its processes in a very timely fashion. Seasoned editors/reviewers will be consulted to review each article(s), profer quality evaluations and polish the articles with expertise before publication.


Simply send your article(s) as an e-mail attachment to manuscripts@acad.gjournals.org or manuscripts.igj@gmail.com.


Call for Books


You are also invited to submit your books for online or print publication. We publish books related to all academic subject areas.    Submit as an e-mail attachment to books@journals.acadpub.online.


Call for Thesis

             



Search

Login Form

Other Journals


Newsletter


Sponsored