本研究使用能表現半乳糖甘酶β-galactosidase (β-gal) 之Pichia Pastoris 酵母菌，使用SDS/chloroform進行Pichia Pastoris 酵母菌細胞通透(permeabilization)，再利用洋菜膠(agar)將其進行固定。實驗分別以5 種試劑進行酵母菌細胞通透測試，結果顯示以01.94×10-3 ％SDS /3.80 ％ chloroform 通透效果最佳，其β-gal 活性可達 7.5×103 unit/mg cell，在將通透過後的酵母菌細胞用洋菜膠進行固定化測試，結果顯示以2% 洋菜膠之固定化效果最好。對此固定化酵素進行各種反應條件探討，最佳條件如下：在pH＝7.5，溫度28 ℃，反應20 分鐘的情況下酵素活性有最高值 3.4×102 unit/mg cell。
β-D-galactosidase from Pichia pastoris ZGZA.Permeabilization of Pichia pastoris cells in relation to β-gal activity was carried out using SDS/chloroform to avoid the problem of β-gal activity. The cell Permeabilization were tested by using different ratio of SDS/chloroform and get a best ratio (1.94 × 10-3 % SDS / 3.80 % of chloroform) to give highest β-gal activity (7.5 × 103 unit / mg cell).Next, the cell was immobilized on agar. Different process parameters (biomass load, pH, temperature, and incubation time) were optimized to enhance the highest β-gal activity .The highest β-gal activity was observed Immobilized of 2% agar with 9.94 mg DW yeast biomass after 20 min of incubation period at optimum pH of 7.5 and temperature of 28 ℃.
