Sustainable quick quantitative screening for the physiology of chitinases production by Bacillus thuriengiensis gallariae and detection of Aedes aegypti biopesticide activity

Roshdy, Amira M.; Abou-Baker, Nesreen H.; Saber, Mohamed; Hamed, Shimaa R.; Sharaf, Omaima A.; El-Bendary, Magda A.; Amer, Mai N.

Sustainable quick quantitative screening for the physiology of chitinases production by Bacillus thuriengiensis gallariae and detection of Aedes aegypti biopesticide activity

Authors

Abstract

Background
Chitin is considered the world’s first and most abundant amino-carbon substrate.
Objective
The proposed method aims to speed up the detection and measuring of microbial chitinase production.
Materials and methods
Solid-state fermentation, plates, viscosity, and spectrophotometric methods were used to detect microbial chitinase activity. Analysis of variance was used for statistical analysis.
Results and conclusion
The trailed Bacillus thuriengiensis gallariae strain was differentiated from other tested strains of Bacillus thuriengiensis in terms of mosquito resistance, besides being superior to other studied Bacillus sphaericus. As anticipated, results from the clear zone plates method were not clear compared with the viscosity method where the strain exhibited the best. Worthy, the same result was reached in the color methods. The superlative incubation period for the physiological properties of chitinase production from Bacillus thuriengiensis gallariae was attained after 5 days. Results indicated that the best size of chitin particles was 1 mm, the best percentage of humidity of the growth was 67%, the best inoculum volume was 10 ml, and the best carbon source for the production of crude chitinases was glucose. The optimal concentration for the production of chitinases was 20% of the weight of the growth medium, yet 5% of the weight of the growth medium was the optimal percentage of glucose as a carbon source for the production of other protein metabolites. The proposed colorimetric method seemed to be an effective and rapid method to survey the aptitude of huge quantities of microorganisms to produce chitinases.

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