ggshell and Membrane-Based Substrate for the Production, Optimization and Detergent Compatibility of Alkaline Protease Enzyme
No Thumbnail Available
Date
2019-07
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
In recent years the advancement of technology results not only development but also,
environmental risks due to the use of chemicals, catalysts and environmentally hazardous
materials moreover coasty. In spite of this, the use of biotechnological principles and products in
the industrial sector is mandatory and expected to with stand the current problems. Though
Microbial alkaline proteases are stimulating tremendous interests in the research and enzyme
market. Hence, the aim of this thesis was the use of eggshell and membrane as a substrate for the
production, optimization and detergent compatibility of alkaline protease using Bacillus subtilis
mojavensis in submerged fermentation. Fermentation process for enzyme production was
conducted using, four factors with three levels were used and 29 experiment had been studied. The
optimum or maximum alkaline protease production was obtained at a temperature of 37
C,
eggshell concentration of 20 %, pH of 9.0 and incubation time of 48 h with a maximum activity of
214 U/ml. Optimum parameters for the production of alkaline protease was found using design
expert optimizer at 9.08 pH, 39.74
0
C, 19.78% eggshell and 48 h of incubation time were obtained.
Alkaline protease enzyme was produced for further analysis such as, characterization and
detergent compatibility of the enzyme. Enzyme activity was conducted in a pH range of 6-12, with
maximum activity obtained at pH 10. It showed that more than 93.97% its original activity was
retained using buffers pH ranging from 8-10, with the optimum activity at pH 10.0. Overall
alkaline protease enzyme was stable between pH 8.0-10.0 attain 90%, 100% and 94% of residual
activity. Its minimum residual activity was attained at pH value of 6.0 which is 39.6% of its original
activity. Alkaline protease was found to be very active at all temperatures tested between 30
0
C
and 80
0
0
C, alkaline
protease was stable and retained more than 74% of its maximum activity. From 1M to 2.0M of
NaCl concentration, exhibits > 97% of optimum activity was recorded at pH 8 and 10. Whereas;
optimum stability was attained at these concentration range between 1.0 - 3.0 M NaCl. At pH 8.0
residual activity were raising as concentration increases and constant after 2.5 M. The detergent
compatibility study was conducted. Results increasing the concentration of enzyme increases the
degradation of blood stain. Therefore, alkaline protease enzyme has compatibility to industrial
application including detergent as an alternative.
C with maximum activity at 60
0
C. Within temperature range of 40
0
0
C - 70
0
0
C alkaline
protease was stable and retained more than 74% of its maximum activity. From 1M to 2.0M of
NaCl concentration, exhibits > 97% of optimum activity was recorded at pH 8 and 10. Whereas;
optimum stability was attained at these concentration range between 1.0 - 3.0 M NaCl. At pH 8.0
residual activity were raising as concentration increases and constant after 2.5 M. The detergent
compatibility study was conducted. Results increasing the concentration of enzyme increases the
degradation of blood stain. Therefore, alkaline protease enzyme has compatibility to industrial
application including detergent as an alternative.
Description
Keywords
Alkaline protease, detergent, BSM, activity, stability