Biomass concentration50 mL of culture was harvested and centrifuged at 7,650 g for5 min. The resultant cell pellet was then washed with saline solu-tion and re-centrifuged. After decanting the supernatant, the cellpellet was dried at 90◦C until all moisture was removed and theweight remains constant. Biomass concentration was determinedas the average of three trials.