Immobilization of Bacterial Cells and Chitinolytic Activity of Streptomyces sp. (PB 2)

Departement of Fisheries, Faculty of Agriculture, Universitas Gadjah Mada, Floral Street, BuildingA4, Bulaksumur Yogyakarta 55281, Indonesia.

^* Corresponding author: ustadi@ugm.ac.id

Abstract

This study was aimed to immobilize the chitinolytic bacteria Streptomyces sp. PB 2 using sodium alginate as immobilization agent. Streptomyces sp. PB 2 was reported have a good chitinolytic activity and immobilization is known to increase the stability of bacteria during repeated used. Sodium alginate has been used on several methods of immobilization and sodium alginate are reported as a good agent. Cell immobilization was done by growing the cell on nutrient broth (NB), mixed with 1% sodium alginate to form the beads, then the mixture were put to a syringe and droped into CaCl2 solution. The beads were washed with 0.85% NaCl solution and filtered. To test the bacterial activity, beads were applied into chitin liquid medium and the chitinolytic activity was observed every 24 hours for 5 days. To test its stability, after the 5^th day, the beads was filtered and put in to chitin liquid medium and tested the chitinolytic activity. This experiment was repeated twice. The highest chitinolytic activity of Streptomyces sp. PB2 was observed on the 4^th day with the value of 0.00014 U/ml and the concentration of NAG of 5.42087 µg/ml with the treatment of immobilized NB medium without the addition of chitin.