Production Characteristics and Molecular Properties of Protease of Pediococcus acidilactici Isolated from Beef under Cold Storage

Aim: To investigate the production characteristics and molecular properties of protease from Pediococcus acidilactici under cold storage temperature.

Study Design: Identification and re-identification of Pediococcus acidilactis and determination of optimal conditions for protease production and molecular properties.

Place and Duration of Study: All the work was carried out in the Department of Microbiology, Faculty of Science, University of Ibadan, Nigeria between March 2014- January, 2015.

Methodology: Identification of the organism was done using API kit. Determination of inoculums concentration was carried using the Neubaeur chamber. pH, incubation period, substrate concentration, influence of ions, were determined by varying this parameters using standard methods to optimise values. Purification of the enzyme was obtained by gel chromatography using sephadex beads G-100, G-50 and finally by the use of sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE).

Results: The highest protease activity of 49.46 units ml-1 was recorded at pH 5.5, temperature of 20ºC, incubation period of 96 h, inoculum size of 0.1 ml (1.70 x 104) with 1% casein substrate concentration in the presence of 0.1 M manganese ion and 0.1M of Ammonium ions concentration. Separation of protease enzyme on SDS-PAGE showed that the molecular weights of the major peaks were found to be within the range of 45-55 kDa.

Applications: This study revealed that bacteria (Pediococcus acidilactici) could be induced for protease production and their applications in industrial spheres were confirmed.