[Study on immobilized cells for producing alpha-amylase by using polyvinyl alcohol as the carrier (I)]

The method of immobilization of Bacillus subtilis by using polyvingyl alcohol(PVA) as the carrier of immobilized cells was studied. The effects of conditions of immobilization on the structure and mechanical strength of PVA immobilized cells and the ability for producing alpha-amylase of the immobilized cells were investigated. The comparative test of fermentation by using the immobilized cells with PVA as carrier and the immobilized cells with sodium glyinate as carrier and free cells was carried out in the same condition. The results showed that Bacillus substilis cells were immobilized efficently by PVA and the immobilized cells could normally grow and reproduce and produce alpha-amylase. In the same condition, the activity of alpha-amylase produced boy the immobilized cells was 28% higher than that produced by free cells and 11% higher than that produced by the cells immobilized with sodium glyinate as carrier.