Screening and Selection of Marine Isolate for l-Glutaminase Production and Media Optimization Using Response Surface Methodology

Abstract

The current work details the screening of about 400 marine isolates from various marine niches, from which one isolate was finally selected based on the productivity of glutaminase (71.23 U/l). Further, biochemical identification tests and 16S rRNA sequencing identified this isolate to be Providencia sp. This isolate was taken up for further media optimization studies by using one-factor-at-a-time approach and subsequently by response surface methodology. A face centered central composite design was employed to investigate the interactive effects of four variables, viz., concentrations of glucose, methionine, urea, and succinic acid on glutaminase production. A significant influence of urea on glutaminase production was noted. Response surface methodology showed that a medium containing (g/l) glucose 10.0, urea 5.15, methionine 3.5, succinic acid 6.0, ammonium sulfate 2.5, and yeast extract 6.0 to be optimum for the production of glutaminase. The applied methodology was validated using this optimized media and enzyme activity 119 +/- 0.12 U/l and specific activity of 0.63 U/mg protein after 28 h of incubation at 25 degrees C was obtained.

Production, purification and characterization of L-Glutaminase from Streptomyces sp. isolated from soil

“…When free sugars were eliminated from the medium, there was production of both biomass and activity (65.74 U/l). This indicated the ability of the organism to utilize other media components for energy (Iyer and Singhal, 2009). Das and Agsar (2013) reported that L-glutamine act as the optimum nitrogen source (30.24±0.01 IU) among all sources tested.…”

“…The effect of pH (ranging from 5-7), incubation temperature (25-40ºC), and different carbon sources (glucose, sucrose and fructose) at 0.2% concentration, nitrogen sources (urea, peptone and lglutamine) at 0.7%, and effect of sodium chloride (ranging from 0.05%-0.15%) were investigated. All experiments were conducted in at least triplicate, and the mean values are calculated (Iyer and Singhal, 2009). …”

“…In food industry, L-glutaminase is used as a flavour enhancer by increasing glutamic acid content in food through hydrolysis of L-glutamine to L-glutamic acid and ammonia. Its commercial importance demands the search for new and better yielding microbial strains and economically viable bioprocesses for its large-scale production (Iyer and Singhal, 2009).…”

Optimization of Cellulase and Xylanase Production by Micrococcus Species under Submerged Fermentation

“…Therefore, a judicious selection of these parameters can dramatically improve the enzyme yield. Several authors have reported increased enzyme yield upon optimization of bioprocess conditions [22,[41][42][43].…”

Process Optimization of L-Glutaminase Production; a Tumour Inhibitor from Marine Endophytic Isolate Aspergillus sp. ALAA-2000

“…Another most promising application of glutaminase is in biosensors for monitoring glutamine levels in mammalian and hybridoma cell cultures without the need of separate measurement of glutamic acid [5]. L-Glutaminase is widely distributed in animal tissues, plants and in a variety of microorganisms including bacteria, fungi and yeast [6][7][8] of which the most potent producers are fungi [9]. On an industrial scale, glutaminases are produced mainly by Aspergillus and Trichoderma [10][11][12][13].…”