Hydrolysis of soybean isoflavonoid glycosides by Dalbergia beta-glucosidases.
Two beta-glucosidases from the legumes Dalbergia cochinchinensis and Dalbergia nigrescens were compared for their ability to hydrolyze isoflavonoid glycosides from soybean. Both D. nigrescens and D. cochinchinensis beta-glucosidases could hydrolyze conjugated soybean glycosides, but D. nigrescens beta-glucosidase hydrolyzed both conjugated and nonconjugated glycosides in crude soybean extract more rapidly. The kinetic properties Km, kcat, and kcat/Km of the Dalbergia beta-glucosidases toward conjugated isoflavonoid glycosides, determined using high-performance liquid chromatography, confirmed the higher efficiency of the D. nigrescens beta-glucosidase in hydrolyzing these substrates. The D. nigrescens beta-glucosidase could also efficiently hydrolyze isoflavone glycosides in soy flour suspensions, suggesting its application to increase free isoflavones in soy products.
Chuankhayan
Phimonphan
P
School of Biochemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand.
Rimlumduan
Thipwarin
T
Svasti
Jisnuson
J
Cairns
James R Ketudat
JR
D035782:Dalbergia / Q000201:enzymology*; D006027:Glycosides / Q000378:metabolism*; D006868:Hydrolysis; D007529:Isoflavones / Q000378:metabolism*; D013025:Glycine max / Q000737:chemistry*; D013045:Species Specificity; D001617:beta-Glucosidase / Q000378:metabolism*
D006027:Glycosides; D007529:Isoflavones; D001617:beta-Glucosidase