Co-expression of saccharifying alkaline amylase and pullulanase in Micrococcus halobius OR-1 isolated from tapioca cultivar soil.

Autor: Devi, Kamakshi, Yogeeswaran, Ganesa
Zdroj: World Journal of Microbiology & Biotechnology; Apr1999, Vol. 15 Issue 2, p223-229, 7p
Abstrakt: Bacterial isolates from Tapioca cultivar soil were systematically identified. The effect of culture conditions and medium components on the production of extracellular amylase and pullulanase by Micrococcus halobius OR-1 were investigated. Amylase and pullulanase activity in the cell-free supernatant reached a maximum of 8.6 U/ml and 4.8 U/ml after 48 h, respectively. The enzyme converted the complex polysaccharides starch, dextrin, pullulan, amylose and amylopectin predominantly into maltotriose. Saccharification of 15% cereal, tuber starches and root starches with the whole cultured cells (WCC) or cell-free supernatant (CFS) showed comparable and complete saccharification within 90 min. These saccharifying enzymes had a pH optimum of 8.0 and were stable over a broad pH range of 6–12. Thus the coexpressed physicochemically compatible extracellular amylase and pullulanase produced by the Micrococcus halobius OR-1 strain might have important value in the enzyme-based starch saccharification industry. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index