आईएसएसएन: 2471-9315
Mustafa M. Omar, Jasim M. Awda
From fifty purified Bacillus spp. Isolates, twenty-six isolates of Levansucrase producing were found. They were isolated from different sources in Baghdad. These isolates were screened for their abilities to produce Levansucrase, it was found that the isolates designated S7, S8, S9, S10, S11, S12, S13, S14, F3, F4, and F5 (as named in this study) the higher producers of this enzyme by Levan formation in the sticky mucous membrane visible around the colonies, which was considered a primary indicator of the production Levansucrase. All isolates were culturally and morphologically identified to confirm they belong to the genus Bacillus sp. The secondary screening was performed on these isolates by estimation Levansucrase assay on the medium of Mineral Salts Broth modified by adding 20% sucrose, as the bacterial isolate Bacillus sp. S8 was obtained from the soil near the rhizosphere of the stevia plant and was superior in the amount of Levansucrase produced, reaching 529.87 U/ml. The identification tests of this isolate were carried out by studying the biochemical tests using the Vitek2 compact system. The test results were confirmed by 16S rRNA gene identification using Polymerase Chain Reaction (PCR) and its nitrogen base sequencing. The results revealed that this isolate belongs to this local isolate Bacillus licheniformis and identified Bacillus licheniformis strain MJ8, and it was registered under the Accession Number in Gene Bank: OM672244.1. The Levan was identified and character after extracting from the efficient local isolate using a High-Performance Liquid Chromatography (HPLC) technique, Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscope (SEM), and Atomic Force Micrograph (AFM) analysis.