title: Improved production of L-asparaginase by Bacillus brevis cultivated in the presence of oxygen-vectors.
abstract: The efficiency of three oxygen-vectors liquid paraffin, silicone oil and n-dodecane in the production of L-asparaginase by Bacillus brevis was evaluated at 4% (v/v) concentration. All of the three oxygen-vectors were found to exhibit a stimulatory effect on L-asparaginase activity. Liquid paraffin at 6% (v/v) resulted in 34% increase in the L-asparaginase activity accompanied by a 48% increase in the production of cell mass at a 10 L scale. This improvement in L-asparaginase activity and cell mass production in the presence of liquid paraffin can be related to the fact that liquid paraffin was capable of maintaining dissolved O2 concentration above 28% through out the course of the fermentation. Maintenance of the dissolved O2 concentration above 28% could be viewed in terms of an adequate oxygen supply to the rapidly dividing cells of the bacterium, which in turn resulted in enhancement in cell mass production and l-asparaginase activity.
authors: Department of Biotechnology, Himachal Pradesh University, Summer Hill, Shimla 171005, India.
authors: Umesh
authors: U
authors: Narta
authors: Sudesh
authors: S
authors: Roy
authors: Shamsher S
authors: SS
authors: Kanwar
authors: Wamik
authors: W
authors: Azmi
mesh_terms: D000473:Alkanes / Q000494:pharmacology*; D001215:Asparaginase / Q000096:biosynthesis*; D001407:Bacillus / Q000187:drug effects / Q000201:enzymology* / Q000254:growth & development*; D018533:Biomass; D005285:Fermentation / Q000187:drug effects; D008899:Mineral Oil / Q000494:pharmacology*; D010100:Oxygen / Q000494:pharmacology*; D012827:Silicone Oils / Q000494:pharmacology*; D014867:Water / Q000494:pharmacology
chemical_list: D000473:Alkanes; D012827:Silicone Oils; D014867:Water; C007548:n-dodecane; D008899:Mineral Oil; D001215:Asparaginase; D010100:Oxygen