Journal of Environmental Treatment Techniques
2020, Volume 8, Issue 3, Pages: 952-960
J. Environ. Treat. Tech.
ISSN: 2309-1185
Journal web link: http://www.jett.dormaj.com
Screening, Characterization and Production of
Thermostable Alpha-Amylase Produced by a Novel
Thermophilic Bacillus megaterium Isolated from
Pediatric Intensive Care Unit
1
1
2*
2
Seyyedeh Narjes Abootalebi , Amir Saeed , Ahmad Gholami , Milad Mohkam , Aboozar
3
3
4
5
Kazemi , Navid Nezafat , Seyyed Mojtaba Mousavi , Seyyed Alireza Hashemi , Eslam
Shorafa2*
1
Department of Pediatrics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
2
Biotchnology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
3
Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
4
Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan
5
Department of Mechanical Engineering, Center for Nanofibers and Nanotechnology, National University of Singapore, Singapore
Received: 09/03/2020
Accepted: 13/06/2020
Published: 20/09/2020
Abstract
This study aimed to isolate the thermophilic Bacillus strain capable of producing a high amount of thermo-stable α-amylase.The
screening and isolation of amylase producing bacteria were done on selective media. The identification of bacteria was made using
routine biochemical and molecular 16s rRNA techniques. The amylase activity assay was performed by using dinitrosalicylic acid (DNS)
m
method, and finally, the optimum temperature, K (Michaelis constant) and maximum rate of reaction (Vmax) of the enzyme was
calculated. Results: The newly thermo-stable amylolytic enzymes of Bacillus megaterium designated AGH01was isolated from pediatric
intensive care unit through a selective enrichment procedure. This isolate was identified based on biochemical and morphological traits
along with 16s rRNA partial sequence analysis. This isolate showed the highest amylolytic activity (19.2 U/mL after 24 h) as compared
to other isolates. The optimum temperature for the enzyme activity was achieved at 90°C and pH 7.0. At this condition, K