SCREENING, ISOLATION, AND BIOCHEMICAL CHARACTERIZATION OF AMYLASE PRODUCED BY Bacillus SPECIES FROM SUDANESE SOIL SAMPLES Authors: Sundos A. Khidir and Elhadi A. I. ElkhalilReceived September 6, 2024Accepted for publication December 26, 2024Published December 30, 2024. Volume 2:2 Pages 126—141Checked for plagiarism YesPeer reviewer comments 2Correspondence: eaikhalil@yahoo.com
Abstract
Many microorganisms, including Bacillus spp., can produce amylases. The search for new promising strains is a continuous process for producing amylase for industrial use. The present study aimed to isolate amylase-producing bacteria in the Sudanese soil and characterize the produced amylase. Six isolates of Bacillus species with the highest amylase activity were selected for further investigations out of 32 isolates obtained from the first screening of soil samples for amylase-producing bacteria. The isolates were identified by conventional bacteriological methods followed by PCR amplification and partial sequencing of the 16S rRNA gene, and their amylase was characterized and quantified. These six isolates were 2 strains of each of B. megaterium and B. subtilis, and one strain of each of B. velezensis and B. licheniformis; their average amylase activities ranged from 4.77 to 6.10 U/ml. The produced amylases were thermo-stable at 60 °Ϲ for 70 min, with Vmax values ranging between 1.08 and 45.66 µmole/min.mg and Km values reaching up to 530.45 mM. The strains of Bacillus species isolated in this study represent promising candidates for amylase production on an industrial scale.
KEYWORDS: Amylase; B. megaterium; B. velezensis; B. subtilis; B. licheniformis.