Abstract
Seventeen (17) strains of macro-fungi were screened for fructosyltransferase (FTase) production, of which Penicillium simplicissimum was selected for further work. FTase production was carried out in shake flask cultured at 30°C and 250 rpm for 48 h. For optimization of one factor-at-a-time method, effects of initial sucrose concentration, fermentation time, pH, inoculum size and agitation speed were studied on growth and extracellular FTase activity. These fermentation parameters were then optimized using response surface methodology (RSM) coupled with a central composite design (CCD). 20 g/l sucrose concentration, 36 h fermentation time, pH 6, 15 ml inoculum size and 150 rpm agitation speed were the optimum parameters obtained from RSM. The experimental values were in good agreement with predicted values within -0.057 to 0.023 errors. Nevertheless, the biomass and FTase (extracellular and intracellular) activities increased from 4.38 - 12.16 g/l, 92.76 - 99.46 IU/ml and 60.73 - 69.98 IU/ml in the unoptimized parameters to 14.16 g/l, 118.86 IU/ml (extracellular) and 71.98 IU/ml (intracellular) in the parameters optimized by RSM, respectively.
Key words: Fructosyltransferase, Penicillium simplicissimum, response surface methodology, fructooligosaccharides.
