Optimization and partial characterization of culture conditions for the production of alkaline protease from Bacillus licheniformis P003

Abstract

Proteolytic enzymes have occupied a pivotal position for their practical applications. The present study was carried out under shake flask conditions for the production of alkaline protease from Bacillus licheniformis P003 in basal medium containing glucose, peptone, K2HPO4, MgSO4 and Na2CO3 at pH 10. The effect of culture conditions and medium components for maximum production of alkaline protease was investigated using one factor constant at a time method along with its characterization. Maximum level of enzyme production was obtained after 48h of incubation with 2% inoculum size at 42°C, under continuous agitation at 150 rpm, in growth medium of pH 9. Highest enzyme production was obtained using 1% rice flour as carbon source and 0.8% beef extract as organic nitrogen source. Results indicated that single organic nitrogen source alone was more suitable than using in combinations and there was no significant positive effect of adding inorganic nitrogen sources in basal medium. After optimization of the parameters, enzyme production was increased about 20 fold than that of in basal medium. The crude enzyme was highly active at pH 10 and stable from pH 7–11. The enzyme showed highest activity (100%) at 50°C, and retained 78% relative activity at 70°C. Stability studies showed that the enzyme retained 75% of its initial activity after heating at 60°C for 1h. The enzyme retained about 66% and 46% of its initial activity after 28 days of storage at 4°C and room temperature (25°C) respectively. Mn2+ and Mg2+ increased the residual activity of the enzyme, whereas Fe2+ moderately inhibited its residual activity. When pre-incubated with Tween-20, Tween-80, SDS and H2O2, each at 0.5% concentration, the enzyme showed increased residual activity. These characteristics may make the enzyme suitable for several industrial applications, especially in leather industries.

Two‐step biological approach for treatment of rapeseed meal

“…Thus, enzyme production was found to be markedly influenced by the medium composition, with the ratio of wheat bran in the substrate, Tween‐80, and the moisture content all emerging as important influencing parameters. Some previous studies have shown that suitable concentrations of Tween‐80 in the medium can induce and improve cellulase and protease production (Sarker, Talukdar, Deb, Sayem, & Mohsina, ; Vu, Pham, & Kim, ). Tween‐80 is routinely included in media for promoting cellulase production and preventing the denaturation of cellulolytic enzymes (Castanon & Wilke, ).…”

Enhanced production and organic solvent stability of a protease fromBrevibacillus laterosporus strain PAP04

“…Protease production is generally influenced by nutritional factors (carbon and nitrogen sources) and environmental conditions (pH, temperature, and incubation periods). There have been several reports on protease production by various bacteria ( 18 19 20 21 ), including those that have investigated the production of organic solvent-stable proteases ( 4 , 6 ). In our study, peak protease production was observed at 48 h of incubation, after which activity likely decreased owing to nutrient depletion.…”

Microbial metabolomics: essential definitions and the importance of cultivation conditions for utilizing Bacillus species as bionematicides

“…; Sarker et al . ). It was found that alkaline media and elevated temperatures reduced the volume of spores, while aeration and agitation rates affected spore cell density (Posada‐Uribe et al .…”

“…A number of studies have investigated the influence of cultivation conditions on Bacillus spore production (Posada-Uribe et al 2015;Xu Zhou et al 2017), while others focused on conditions for optimum protease production (Ray et al 2012;Sarker et al 2013). It was found that alkaline media and elevated temperatures reduced the volume of spores, while aeration and agitation rates affected spore cell density (Posada-Uribe et al 2015;Xu Zhou et al 2017).…”