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Title:	Optimization of itaconic acid production by native isolates Aspergillus terreus SUK-1 and Trichoderma asperellum Sl2) using glucose, palm kernel cake and rice straw via submerged culture and solid substrate fermentation
Authors:	Helia Hajian (P62923)
Supervisor:	Wan Mohtar Wan Yusoff, Prof. Dr.
Keywords:	Itaconic acid Polymerization Universiti Kebangsaan Malaysia -- Dissertations Dissertations, Academic -- Malaysia
Issue Date:	22-Jan-2019
Description:	Low productivity of itaconic acid by Aspergillus terreus SUK-1 (local isolate) and replacement of agricultural waste (palm kernel cake and rice straw) instead of glucose to reduce cost of itaconic acid are main motivation for itaconic acid optimization. Two fungi (A. terreus Suk-1 and T. asperellum Sl2) were used to explore their capacity to produce itaconic acid. PKC and RS as accessible and lignocellulosic residue in Malaysia were used for itaconic acid production. The productivity of itaconic acid was studied in a submerged culture fermentation (SCF) using glucose as carbon source and employing immobilized A. terreus SUK-1 and T. asperellum SL2 on polyurethane foam. Response Surface Methodology (RSM) with central composite design (CCD) was employed to optimize the production of itaconic acid by both fungi based on three variables: pH, temperature and various NH4NO3 concentration. Also, the effect of CuSO4, ZnSO4, FeCl3 and CaCl2 were studied using one-factor-at-a-time method in SCF with glucose as the substrate. In addition, the physicochemical parameters (temperature, pH, substrate concentration, inoculum size, moisture content, different nitrogen source and different phosphate concentration) and effect of aeration on itaconic acid in SSF using PKC and RS as substrate by both fungi were investigated. The ANOVA analysis from RSM by A. terreus SUK-1 showed that the quadratic model was significant (P<0.001) and all tested parameters showed significant effect on itaconic acid production. The estimated optimal parameters for itaconic acid production were at pH 2.6, temperature of 32˚C and NH4NO3 concentration of 1.77 g/L. The maximum productivity of itaconic acid by A. terreus SUK-1 after optimization of Cu2+, Zn2+, Fe3+ and Ca2+ was 243 mg/L.h at the following process parameters, 10 mg/L CuSO4, 3 mg/L ZnSO4, 2 mg/L FeCl3 and 7.5 g/L CaCl2. On the other hand, the ANOVA analysis from RSM by T. asperellum SL2 showed that the quadratic model was significant (P<0.001) and all tested parameters showed significant effect on itaconic acid production by T. asperellum. The estimated optimal parameters for itaconic acid production were at pH 3.3, temperature of 28˚C and NH4NO3 concentration of 2.44 g/L. The concentrations of 5 mg/L ZnSO4, 10 mg/L CuSO4, 2 mg/L FeCl3 and 5 g/L CaCl2 were found to be the best conditions for itaconic acid production in SCF using glucose as substrate. The optimum productivity of itaconic acid by T. asperellum SL2 was 38.5 mg/L.h. In SSF, after optimization of inoculum size (1 mL in 10 g substrate), moisture content (70%), nitrogen source (corn steep liquor), phosphate concentration (1% for PKC and 0.5% for RS), temperature (33˚C) and pH (3.5), the productivity of itaconic acid by A. terreus SUK-1 using PKC and RS were 27.77 mg/L.d and 10.03 mg/L.d, on the other hand, by T. asperellum SL2 resulted in 19.25 mg/L.d and 6.12 mg/L.d, respectively. In SSF, the flask was fabricated to increase the aeration rate leading to the enhancement of itaconic acid production. Maximum productivity (97.41 mg/L.d) of itaconic acid was achieved using 20 g PKC by A. terreus SUK-1. In conclusion, itaconic acid productivity by A. terreus SUK-1 in SCF (glucose as substrate) was increased. In SSF, A. terreus SUK-1 produced more itaconic acid using PKC in comparison to RS and applying aeration had increased production of itaconic acid.,Ph.D.
Pages:	211
Call Number:	QD281.P6H335 2019 tesis
Publisher:	UKM, Bangi
Appears in Collections:	Faculty of Science and Technology / Fakulti Sains dan Teknologi

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