Abstract:
Amylase is one of the most widely used enzyme in industries from decades. Its
main function is to hydrolyze the starch molecule into glucose unit and
oligosaccharides. Among different types of amylases, α-amylase is in high
demand due its wide spread use in food, textile, baking and detergent industries.
It can be acquired from microorganisms, plants and animals. This study was
conducted with the aim to isolate, identify and to characterize the amylase
enzyme produced by microorganisms from soil. The soil sample were collected
from the different places of Dharan. The screening of amylase producing
microorganisms were carried out by starch hydrolysis test on starch agar plates.
The organisms producing highest zone of clearance were identified and further
used for amylase production and characterization. Based on colonial
characteristics, cultural characteristics, staining and biochemical test the
organisms were identified as Bacillus subtilis whereas the isolated fungi was
identified as Aspergillus niger on the basis of colonial characteristics and LPCB
staining. The identified organisms were further used for the production of
amylase on submerged fermentation. The amylase activity was assayed by DNS
method. The produced enzyme was centrifuged and partially purified using
ammonium sulphate. The amylase production was found to be maximum at 40ºC
and 6.5 pH for Bacillus amylase and 30 ºC and pH 7.5 for Aspergillus niger.
Further, Characterization of the enzyme was done for the industrial application
of the enzyme. Crude amylase showed its maximal activity at pH 7 and 45 ºC
For Bacillus subtilis and 30 ºC and pH 6.5 for Aspergillus niger. Crude amylase
showed great potential for its application in detergent industry
Description:
On the recommendation of Mr. Hemanta Khanal, Assistant
Professor, this dissertation work of Miss Pratima Rai entitled
“Isolation, Identification and Characterization of Amylase
Enzyme Produced By Microorganisms Isolated From SOIL”
has been approved for the examination and is submitted to the
Tribhuvan University in partial fulfillment of the requirements for
M.Sc Degree in Microbiology(Public Health)
