Sains Malaysiana 44(7)(2015): 973–977

 

Modeling of Sago Starch Hydrolysis Using Glucoamylase

(Pemodelan Hidrolisis Kanji Sagu dengan Glukoamilase)

 

 

LONG WEE LA1I*, FAIZAL YAHAYA1 & MOHAMAD SUFFIAN MOHAMAD ANNUAR2

 

1Faculty of Science and Biotechnology, Universiti Selangor, 45600 Bestari Jaya, Selangor Darul Ehsan, Malaysia

 

2Institute of Biological Sciences, Faculty of Science, Universiti Malaya, 50603, Kuala Lumpur

Malaysia

 

Diserahkan: 10 Februari 2014/Diterima: 26 Februari 2015

 

ABSTRACT

 

A mathematical model based on Michaelis-Menten kinetics was proposed and used to simulate the sago starch hydrolysis and the remaining sago starch concentration. The simulation model was tested with comparison to the real experimental results. The glucoamylase enzyme (E.C. 3.2.1.3) from Aspergillus niger was employed in the present study to hydrolyze the substrate i.e. sago starch into reducing sugars. The experiment was performed in a two liter (2 L) stirred tank reactor. The quantitative effects such as temperature, substrate concentration, enzyme amount, pH and agitation speed were set to optimal value at , 1.0, 0.2 , pH4.5 and 100 , respectively. The computer software, Polymath® 6.0 was employed in this research. The numerical method based on Runge-Kutta Fehlberg 45 was used to solve the system of non-linear ordinary differential equations (ODEs) of sago starch hydrolysis. The model prediction well agreed with experimental results where the high values of regression coefficient,  = 0.9643 was obtained.

 

Keywords: Glucoamylase; Michaelis-Menten kinetics; sago starch; reducing sugar; simulation model

 

ABSTRAK

Model matematik berasaskan kinetik Michaelis-Menten telah dicadang dan digunakan untuk mensimulasikan hidrolisis kanji sagu dan kepekatan kanji sagu yang tertinggal. Model simulasi ini telah diuji dengan perbandingan keputusan eksperimen. Enzim glukoamilase (EC 3.2.1.3) daripada Aspergillus niger telah pun diguna pakai dalam kajian ini bagi tujuan menghidrolisiskan substrat iaitu kanji sagu ke gula penurun. Eksperimen ini dijalankan dalam tangki reaktor 2 L. Kesan kuantitatif seperti suhu, kepekatan substrat, jumlah enzim, pH dan kelajuan perolakan telah dilaraskan pada nilai optimum iaitu masing-masing, 1.0 , 0.2 , pH4.5 dan 100. Perisian komputer Polymath® 6.0 telah digunakan dalam penyelidikan ini. Kaedah berangka berdasarkan Runge-Kutta Fehlberg 45 juga digunakan bagi menyelesaikan sistem persamaan pembezaan biasa tidak linear untuk hidrolisis kanji sagu. Jangkaan keputusan model ini adalah bertepatan dengan keputusan eksperimen dengan nilai pekali regresi yang tinggi,  = 0.9643 telah diperoleh.

 

Kata kunci: Glukoamilase; kinetik Michaelis-Menten; kanji sagu; gula penurun; model simulasi

 

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*Pengarang untuk surat-menyurat; email: zki@unisel.edu.m

 
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