ALKALINE PROTEASE PRODUCTION BY Bacillus licheniformis LBA 46 IN A BENCH REACTOR: EFFECT OF TEMPERATURE AND AGITATION

Abstract

The production of protease from Bacillus licheniformis LBA 46 was studied in a 6 L reactor using the experimental design tool. The higher protease production was obtained in the exponential phase of growth reaching maximum activity (~3,000 U/mL) after 48 h of fermentation at 30 ºC and 300 rpm in a culture medium made of agroindustrial by-products. In the thermostability study, the semi-purified enzyme retained about 78% of the initial activity after 120 min at 50 ºC. The protease was purified 3.33 times by ammonium sulfate precipitation and DEAE-Sepharose column chromatography and had a molecular mass estimated at 40 kDa by SDS-PAGE. The purified protease showed optimum activity at 50 and 60 ºC, optimal activity in pH 8.5 and stability in the range between pH 5-10 after 24 h of incubation at 4 ºC, presenting more than 86% of the initial activity.

Kinetic and Thermodynamic Characterization of the Protease from Bacillus licheniformis (ATCC 12759)

“…The energy required for the activation was determined using methods developed by Souza et al (2015), Castro and Sato (2014), and Aguilar et al (2019). First, the protease was incubated on 1 % of casein solution at various temperatures (35 to 65 o C) for 10 min.…”

“…Proteases or proteolytic enzymes are natural catalysts that act in the degradation of protein by hydrolyzing peptides bonds (Rao et al, 1998;Aguilar et al, 2019;Jisha et al, 2013). They usually require metals ions and or cofactors for the maximal efficiency.…”

Optimization of Alkaline Protease Production by Solibacillus silvestris, Isolated from Gir Region of Gujarat

“…Mangrove ecosystem is most unique as it is exposed to the periodic flooding of seawater and fresh water in case of the estuarine area, salinity variation, a lack of oxygen due to muddy soils and these frequent changes influence the transformation of organic matter into nutrients [1]. The change in organic matter and nutrients as well as extreme environments as a result has impact on biodiversity of mangrove ecosystem.…”

“…Among different types of enzymes produced by microbes, protease which is capable of hydrolyzing the peptide bond in protein molecule represents one of the three largest groups of industrial enzymes. Protease enzymes have wide applications in various industries such as in the detergents, cheese maturation, beer production, meat softening, functional hydrolysate production, and in bioremediation [3][4][5]. The enzyme also has a significant role in many physiological and pathological processes i.e.…”

“…carbon source, nitrogen source, etc.) and therefore optimization of the factors is essential to improve the protease yield [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. A number of statistical experimental designs with response surface methodology (RSM) have been employed for optimizing enzyme production from microorganisms [21].…”