Biotechnological production of highly soluble daidzein glycosides using Thermotoga maritima maltosyltransferase.
The use of soybean isoflavones in food products is limited due to their low hydrophilicity. To enhance its solubility, the isoflavone daidzin was transglycosylated as a model compound using Thermotoga maritima maltosyltransferase (MTase). Four novel transglycosylation products of daidzin were identified by TLC and MALDI-TOF MS: daidzein 7-O-triglucoside, daidzein 7-O-pentaglucoside, daidzein 7-O-heptaglucoside, and daidzein 7-O-nonaglucoside. The major product, daidzein 7-O-triglucoside, was purified by C(18) and gel filtration chromatography, and its molecular structure was determined using UV, IR, MALDI-TOF MS, and NMR. The solubility of daidzein 7-O-triglucoside was 7.5 x 10(4) times that of daidzin, suggesting that the transglycosylation greatly enhanced its water solubility.
Li
Dan
D
National Research Laboratory for Functional Food Carbohydrate and Center for Agricultural Biomaterials, Seoul National University, Shillim-dong, Kwanak-gu, Seoul 151-742, South Korea.
Park
Jin-Hee
JH
Park
Jong-Tae
JT
Park
Cheon Seok
CS
Park
Kwan-Hwa
KH
D001709:Biotechnology / Q000379:methods*; D005964:Glucosyltransferases / Q000378:metabolism*; D006031:Glycosylation; D007529:Isoflavones / Q000096:biosynthesis* / Q000737:chemistry; D015394:Molecular Structure; D012995:Solubility; D013025:Glycine max / Q000737:chemistry; D020124:Thermotoga maritima / Q000201:enzymology*; D014867:Water
D007529:Isoflavones; D014867:Water; C004742:daidzein; D005964:Glucosyltransferases; C436710:maltosyltransferase