Lactic Acid Production from Old Oil Palm Trunk Sap in the Open Batch, Open Repeated Batch, Fed-Batch, and Repeated Fed-Batch Fermentation by Lactobacillus rhamnosus ATCC 10863

The cost of fermentable sugars added as a substrate is one major problem for economic lactic acid (LA) production. Old oil palm trunks (OPT) squeezed sap, the agricultural wastes on replanting and pruning (Elaeis guineensis), contained mainly glucose fructose potential feedstock to use vast carbon source LA To improve yield productivity, various fermentation modes were performed by Lactobacillus rhamnosus ATCC 10863 using OPT sap basal medium. A modified constant feed mode fed-batch repeated undiluted medium can achieve high average concentration 95.94 g/L, 1.04 g/g, productivity 6.40 g/L/h) at 11 h cultivation time. It also provide open batch with an 91.30 0.87 3.88 g/L/h 21