PLANT ROOT AS A SOURCE FOR THE ISOLATION AND CHARACTERIZATION OF β-GLUCANASE PRODUCING BACTERIA

Abstract

Background:  β-glucanase is an important enzyme, which is found in abundance in plant roots. This enzyme hydrolyzes cellulose into a simple sugar i.e. glucose. It finds numerous applications in numerous industries such as brewing industry, cosmetics, medicine etc.

Purpose: The following study is set with the goal of isolating the bacterial β-glucanase-producing isolates of plant roots. It also further aims to identify and examine the ideal parameters in which the β-glucanase producing bacteria exhibit the greatest growth. This may assist the researchers in developing a satisfactory base in extending the applications of β-glucanase enzyme to different sectors and industries such as brewing, cosmetics, medicines etc.

Methodology: The samples of plant roots were taken from the premises of Lahore College of Women University (LCWU), Lahore. Bacterial isolates were obtained and purified, followed by screening for β-glucanase activity using Congo red staining. Gram staining and endospore staining were performed to characterize the morphological features of the isolates. Once identified, DNS assay was done at different temperatures and pH levels, at different carbon and nitrogen sources and at different incubation periods to determine the optimum extracellular and intracellular activity of the enzyme. Some softwares including messsager tool, ExPASy tool and predict protein etc. were used for bioinformatical analysis.

Results: It was found that the isolated bacteria were Bacillus species. The β-glucanase enzyme had the highest extracellular and intracellular activity of 0.82 ± 0.2500U/ml and 0.70 ± 0.2500U/ml respectively at an incubation time of 96 hours. The findings implied that the most suitable carbon source to the enzyme activity is glucose (0.28 ± 0.19519 U/ml) and the most suitable nitrogen source is the yeast extract (0.32 ± 0.2500 U/ml) and peptone (0.68 ± 0.2500 U/ml). The enzymatic activity was highest in the pH of 8.0 (0.42 ± 0.300 U/ml) and 7.0 (0.85 ± 0.2200 U/ml). MnSO₄ (Manganese sulfate) was the most observed source of metal ions with the extracellular and intracellular activities of 1.08 ± 0.0500 U/ml and 1.01 ± 0.1500 U/ml, respectively. 217 triplets and codons were obtained in bioinformatic analysis.

Conclusion: To conclude, the current research shows that Bacillus-associated β-glucanase has an industrial value (which can be possibly applied in brewing, cosmetics, and medical industry) and gives a general understanding of the characteristics of this enzyme.