Stenotrophomonas maltophilia Gd2: A potential and novel isolate for fibrinolytic enzyme production

Abstract

The bacterium with an ability to produce extracellular fibrinolytic protease was isolated and identified as Stenotrophomonas maltophilia Gd2 based on ribotyping. The in-vitro fibrinolytic profile of this enzyme depicted 73% of fibrin clot dissolution within 4 h. Fibrinolytic enzyme yield influenced by different physiological (incubation time, temperature, agitation and pH), nutritional (macronutrients such as carbon and nitrogen sources) and biological (inoculums age and inoculums concentration) parameters of fermentation which were optimized based on one-factor-at-a-time (OFAT) approach. The enzyme yield improved from 886 to 1795 FU ml−1 upon OFAT; optimized conditions include temperature – 33 °C, pH – 8.0, incubation time – 36 h, agitation – 150 RPM, 3% v/v inoculums and age of inoculum – 18 h. Further optimization of enzyme production was achieved with implementation of Plackett-Burman media designing where the production levels increased to 3411 FU ml−1 and noticed that peptone, pH, dextrose and K2HPO4 was found to be significant factor. This ms reports the highest fibrinolytic enzyme yield with S. maltophilia to that of literature reports. Keywords: Fibrinolytic enzyme, Stenotrophomonas maltophilia Gd2, One-factor-at-a-time (OFAT) approach, Plackett-Burman designing method