Prestasi β-galaktosidase (β-Gal) disekat gerak pada sokongan citosan telah dikaji dalam proses kelompok. Sokongan citosan telah diaktifkan dengan menggunakan ejen kimia iaitu larutan glutaraldehid. Objektif utama kajian ini adalah untuk mengkaji keadaan yang sesuai dalam penyediaan proses menyekat gerak β-Gal untuk mendapatkan nilai aktiviti β-Gal yang tinggi. Semasa penyediaan β-Gal disekat gerak, keputusan keadaan optimum telah diperoleh daripada Kaedah Gerak Balas Permukaan (KGBP). Keadaan optimum yang telah diperoleh untuk kepekatan larutan glutaraldehid dan β-Gal adalah masing-masingnya sebanyak 2% dan 10 mg/ml, yang telah memberi keputusan 65.52% untuk hasilan aktiviti manakala untuk hasilan menyekat gerak adalah sebanyak 94.57%. Keputusan eksperimen untuk mengkaji kesan suhu ke atas aktiviti β-Gal, didapati suhu optimum pada 58℃ telah diperolehi selepas proses menyekat gerak β-Gal. Walau bagaimanapun, ia sangat menarik apabila merujuk kepada julat haba yang lebih luas, β-Gal disekat gerak menunjukkan kestabilan operasi yang lebih baik berbanding dengan β-Gal bebas. Aktiviti β-Gal disekat gerak telah meningkat lebih dari 17% daripada aktiviti awalnya, manakala aktiviti β-Gal bebas berkurang ke 15%. Kestabilan yang tinggi pada β-Gal akan membawa kepada kebolehsaknaan menggunakannya semula yang lebih baik. β-gal disekat gerak boleh digunakan semula sebanyak enam kitaran dan kira-kira 50% daripada aktiviti awalnya dapat dikekalkan.
_______________________________________________________________________________________________________
The performance of immobilized β-galactosidase (β-Gal) onto chitosan support was studied in a batch process. The chitosan support was activated by using chemical agent which was glutaraldehyde solution. The main objective of this research was to investigate the suitable conditions in preparation of β-Gal immobilization process that will produce greater β-Gal activity. During the preparation of immobilized β-Gal, the optimum conditions were obtained from Response Surface Methodology (RSM). The optimum conditions were found to be 2% and 10 mg/ml for glutaraldehyde and β-Gal concentrations, respectively, which has resulted in 65.52% for activity yield meanwhile for immobilization yield, is 94.57%. The experimental results for investigation of effect of temperature on β-Gal activity, found that the optimum temperature at 58℃ was obtained after β-Gal immobilization. However, it is so interesting that the immobilized β-Gal showed much better operational stability referring to a broader thermal range as compared to free β-Gal. The activity of immobilized β-Gal increased at about more than 17% of its initial activity, meanwhile the activity of free β-Gal reduced at less than 15%. Higher stability of β-Gal will lead to a better reusability. The immobilized β-Gal can be reused for six cycles and retained approximately 50% of its initial activity.
Immobilization of β-galactosidase onto activated chitosan support by using covalent binding method / Nur Syahirah Sezale