Feeding strategies for the enhanced production of α-arbutin in the fed-batch fermentation of Xanthomonas maltophilia BT-112

To develop a cost-effective method for the enhanced production of alpha-arbutin using Xanthomonas maltophilia BT-112 as a biocatalyst, different fed-batch strategies such as constant feed rate fed-batch, constant hydroquinone (HQ) concentration fed-batch, exponential fed-batch and DO-control pulse fed-batch (DPFB) on alpha-arbutin production were investigated. The research results indicated that DPFB was an effective method for alpha-arbutin production. When fermentation with DO-control pulse feeding strategy to feed HQ and yeast extract was applied, the maximum concentrations of alpha-arbutin and cell dry weight were 61.7 and 4.21 g/L, respectively. The alpha-arbutin production was 394 % higher than that of the control (batch culture) and the molar conversion yield of alpha-arbutin reached 94.5 % based on the amount of HQ supplied (240 mM). Therefore, the results in this work provide an efficient and easily controlled method for industrial-scale production of alpha-arbutin.