LAUSR

Sorbitol production from Meranti wood sawdust (MWS) using immobilized cells of Lactobacillus plantarum (BAA-793) with repeated batch fermentation via solid state fermentation (SSF) was studied. The storage stability of the immobilized cells, entrapped in sodium alginate beads was also investigated. This study started with the pretreatment of the MWS to recover the cellulose, followed by the entrapment of the bacterial cells in sodium alginate, then the fermentation process via SSF. The results showed that the storage stability of the immobilized cells in gel beads at 4°C were more stable when compared to stability at 35°C, even with high cell concentration. The cell concentration, when stored at 4°C showed great stability up to 2 days but started to decrease slightly as the storage time was extended to 5 days. The concentration of the cells was about log 10.23 CFU/mL (1.70 x 10 CFU/mL) after 2 days, and log 9.48 CFU/mL (3.00 x 10 CFU/mL), log 9.47 CFU/mL (2.98 x 10 CFU/mL) and log 9.44 CFU/mL (2.80 x 10 CFU/mL) after 3 to 5 days, respectively. The decrease in the concentration was not significant within the studied period of storage at 4°C. The repeated batch fermentation for sorbitol production through the reuse of the entrapped cells showed that the same bead cells can be reused for the fermentation process up to 5 cycles. The production of sorbitol using the immobilized cells of Lactobacillus plantarum (BAA-793) through solid state fermentation process showed a good result due to the high concentration of cells entrapped in the beads, giving rise to a high sorbitol production.