The invention discloses a method for catalytically synthesizing
curcumin glycoside compounds by a biological method. A
glycosyl transferase gene CaUGT2 and a
sucrose synthase
gene AtSUS1 are constructed on an
expression vector and are introduced into
escherichia coli to obtain a recombinant strain, the soluble expression quantity of the recombinant strain after induced expression is improved compared with that of
glycosyl transferase from other plants, and a substrate
curcumin can be efficiently catalyzed. A recombinant
plasmid is pRSF-CaUGT2-AtSUS1, a
sucrose synthase AtSUS1
gene is inserted into Nco I and EcoR I,
glycosyl transferase CaUGT2 is inserted into Xho I and
NdeI, a co-expression recombinant
plasmid pRSF-CaUGT2-AtSUS1 is formed, the recombinant
plasmid is transformed into
escherichia coli BL21 (DE3) competent cells, and a recombinant strain CaUGT2-AtSUS1 is obtained. After the recombinant strain is subjected to induced expression, the soluble expression quantity of the glycosyl transferase CaUGT2 is increased compared with that of glycosyl transferase from other plants, the conversion rate of catalytic synthesis of
curcumin glycoside compounds reaches 98%, curcumin is catalyzed to generate curcumin monoglucoside and curcumin diglucoside, the water
solubility of the curcumin monoglucoside and curcumin diglucoside is superior to that of curcumin, and the problem that curcumin is poor in water
solubility is solved. The concentration of the substrate curcumin is 75 mM, the concentration of a catalytic substrate is relatively high, and the method is more suitable for food and
medicine industries in industrialization.