High recovery of intracellular recombinant HBsAg from Pichia pastoris via continuous pulsed laser cell disruption...

In our previous study, we demonstrated that continuous power laser could be a clean, rapid, and convenient alternative to the other conventional disruption techniques for the release of recombinant hepatitis B surface antigen (rHBsAg) from Pichia pastoris. In the current work, we examined the effect of pulsed laser in the continuous laboratory-scale process on cell disruption. Design-of-experiments (DOE) methodology was used for optimization of cell disruption process to obtain the highest protein concentration in the disruption buffer. Our investigations for the pulsed laser at wavelength of 1,064 nm demonstrated that for disrupting P. pastoris cell and releasing rHBsAg, the laser power was the most influential factor, and laser pulse duration and cycle number were in the second and third places. According to the results, the effect of laser power and pulse duration (time) had a direct relationship with protein concentration. For the number of cycles, however, increasing the value from the lowest point at first led to the enhancement and then reduction of protein concentration. The maximum cell disruption and rHBsAg release were recorded for the laser system in the energy input of 284 mW and the pulse duration of 100 mSec after four complete rounds of circulation.