Enzymatic synthesis of piceid glucosides using maltosyltransferase from Caldicellulosiruptor bescii DSM 6725.

Piceid is widely used in food, cosmetics, and pharmaceuticals because of its therapeutic benefits. However, the use of piceid as a drug is limited because of its low solubility. To increase solubility, we synthesized piceid glucosides using maltosyltransferase from Caldicellulosiruptor bescii. The MTase gene was cloned and expressed in Escherichia coli. The enzyme had a unique transfer specificity to the transfer of maltosyl units. Four piceid transglycosylation products were present and identified by thin-layer chromatography and recycling preparative high-performance liquid chromatography. The major product was purified by C(18) and gel filtration chromatography, and its molecular structure was determined using nuclear magnetic resonance spectroscopy to be α-D-maltosyl-(1→4)-piceid. The solubility of maltosyl piceid was 8.54 × 10(3) and 1.86 × 10(3) times those of natural resveratrol and piceid, respectively, suggesting that the transglycosylation greatly increased the water solubility. This suggests that dietary intake of this compound can enhance the bioavailability of resveratrol in the human body.