Microbial Levan from Arthrobacter globiformis Strain KX 146411.1: Characterization and Enhancement of Production

Abstract

Levan producing bacteria was isolated from rhizosphere soil. The molecular identification of this isolate was conducted using 16S rRNA, which resulted in a sequenced region of 1295 base pairs. The sequence alignment in the gene bank indicated that this isolate has a high percentage of similarity (98%) to the retrieved consensus sequence of Arthrobacter globiformis strain JCM 1332. The produced levan was characterized using TLC. The effects of nutritional and physical factors on this isolate’s levan production were investigated. The results demonstrated that the optimal sources for carbon and nitrogen during levan production were sucrose and casein, yielding 7.8 g/l and 8.24 g/l of levan, respectively. The highest levan yield 8.6, 7.8, 8.6, 8.53 and 8.27 g/l were obtained at 300 g/l sucrose, pH of 7.8, 33°C, 72 h period of incubation and 150 rpm respectively.