Chuankhayan Phimonphan, Rimlumduan Thipwarin, Svasti Jisnuson, Cairns James R Ketudat
School of Biochemistry, Institute of Science, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand.
J Agric Food Chem. 2007 Mar 21;55(6):2407-12. doi: 10.1021/jf062885p. Epub 2007 Feb 21.
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.
对来自越南黄花梨（Dalbergia cochinchinensis）和黑黄檀（Dalbergia nigrescens）这两种豆科植物的两种β-葡萄糖苷酶水解大豆异黄酮苷的能力进行了比较。黑黄檀和越南黄花梨的β-葡萄糖苷酶都能水解结合型大豆苷，但黑黄檀的β-葡萄糖苷酶能更快速地水解粗大豆提取物中的结合型和非结合型苷。使用高效液相色谱法测定的黄檀属β-葡萄糖苷酶对结合型异黄酮苷的动力学参数Km、kcat和kcat/Km，证实了黑黄檀β-葡萄糖苷酶在水解这些底物方面具有更高的效率。黑黄檀的β-葡萄糖苷酶还能有效水解大豆粉悬浮液中的异黄酮苷，表明其可用于增加豆制品中的游离异黄酮。
