Production of fructosyltransferase by penicillium simplicissimum in submerged culture
| dc.contributor.author | Mortan, Siti Hatijah (Binti) | |
| dc.date.accessioned | 2015-08-25T07:07:24Z | |
| dc.date.available | 2015-08-25T07:07:24Z | |
| dc.date.issued | 2010-07 | |
| dc.description.abstract | Fructosyltransferase (FTase) is an enzyme responsible for the production of fructooligosaccharides (FOS). FOS is an important ingredient in the cosmetic, agrochemical, pharmaceutical and food industries. Recent increase in the demand of FOS has led to new search of FTase producing microorganism and a low cost substrate. Seventeen fungal isolates from different genera (Trametes, Pycnoporous, Lentinus, Schizophyllum, Penicillium, Aspergillus and Trichoderma) were evaluated for FTase production. Penicillium simplicissimum was found to attain the highest cell growth at 3.8 g/L and FTase activities of 506 IU/ml for extracellular and 128 IU/ml for intracellular, respectively. Sugarcane juice was found to have the highest sucrose concentration at 1.249x 103 g/L among the seven sources oflocal sugar tested. In shake flask culture, FTase production were carried out using "one-factorat- a-time" method and a statistical design approach response surface methodology (RSM) coupled with central composite design ( CCD). The optimum culturt conditions was obtained at sugarcane juice concentration 20 g/L, fermentation time 36 h, pH 6, inoculum size 15% (v/v) and agitation speed 150 rpm with extra-cellular FTase activity of 118.86 IU/mL, intracellular activity of 71.97 lU/mL and biomass concentration of 14.16 g/L, respectively. In bioreactor studies, the effect of initial sugarcane juice concentration, agitation speed and rate of aeration for the optimization of FTase from Penicillium simplicissimum were also investigated using a statistical tool, RSM. Results showed that aeration rate of 2 vvm, agitation speed of 200 rpm and initial sugarcane juice concentration of 30 g/L had a maximum extracellular FTase activity of 161.17 IU/mL. Under such condition, maximum specific growth rate (Jlmax) of 0.877 h- 1 and biomass yield to sucrose consumed (Yxs) of 0.667 gig were obtained. The prediction of FTase activity and P.simplicissimum growth using Artificial Neural Networks (ANN) were also highlighted in this study. One step-ahead prediction process through bootstrap resampling method have proved to be consistent with the experimental data with R2 of 0.9903 and 0.9937 for FTase activity and biomass concentration, respectively. An unstructured kinetic models namely the Logistic, the Monod, the Logistic incorporating Leudeking-Piret-like equation were proposed and validated. The models were suitable to describe biomass growth, substrate utilization and FTase production at different initial sugarcane juice concentration ranged from 1 0-50 g/L in batch culture. The inhibition of substrate on the growth of the P.simplicissimum was also studied. The data fit the competitive model with R2 of0.864. The FTase enzyme was also characterized with respect to thermostability, pH stability, optimum temperature and pH. The maximum activities were observed at 55°C and pH 5.5. The Lineweaver-Burk plots gave the Km and v;nax values of 6.51 g/mL and 6.39 IU/mL.min, respectively. Three enzyme kinetic models have been proposed and validated to explain the behaviour of enzyme activity and reaction rates. For deactivation of the FTase, first order enzyme deactivation model satisfactorily fit the experimental data with R2 range from 0.971 to 0.979. Enzymatic reaction rates model as a function of temperature and reaction time has been selected as the model is able to fit the experimental data correctly in wide range of temperature with R2 of 0. 982. In inhibition of the enzyme, a competitive inhibition model fitted the experimental data better than non-competitive and un-competitive with R2 of0.961. | en_US |
| dc.identifier.uri | http://hdl.handle.net/123456789/1097 | |
| dc.subject | Fructosyltransferase | en_US |
| dc.subject | Penicillium simplicissimum | en_US |
| dc.subject | Submerged culture | en_US |
| dc.title | Production of fructosyltransferase by penicillium simplicissimum in submerged culture | en_US |
Files
License bundle
1 - 1 of 1
Loading...
- Name:
- license.txt
- Size:
- 1.71 KB
- Format:
- Item-specific license agreed upon to submission
- Description: