Production of 5-O-α-glucosylgingerol via glucosylation of 6-gingerol by Ensifer sp. M-26

Abstract

6-Gingerol ((S)-5-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-3-decanone), the major gingerol present in ginger rhizomes, has been found to prevent fat accumulation and improve blood flow. However, its low solubility in water and strong pungent odor often limit its potential applications such as in functional foods. In order to overcome these disadvantages, we investigated microbial glucosylation of 6-gingerol by the soil bacterium Ensifer sp. M-26. 5-O-α-Glucosylgingerol was found to be produced from a mixture of maltose and 6-gingerol by the action of washed cells of Ensifer sp. M-26. The addition of organic solvents, such as hexane, to the reaction mixture enhanced 5-O-α-glucosylgingerol production. When the microbial reaction was carried out with 1.3 g/L of 6-gingerol and 100 g/L of maltose under optimized conditions, 0.40 g/L of 5-O-α-glucosylgingerol was accumulated in 25 h. The molar yield of 5-O-α-glucosylgingerol was 19.9 mol%.