TRANSGLYCOSYLATION TO HESPERIDIN BY CYCLODEXTRIN GLUCANOTRANSFERASE FROM AN ALKALOPHILIC BACILLUS SPECIES IN ALKALINE PH AND PROPERTIES OF HESPERIDIN GLYCOSIDES

Cyclodextrin glucanotransferase [1,4-alpha-D-glucan 4-alpha-D-(1,4-glucano)-transferase, cyclizine; CGTase, EC 2.4.1.19] from an alkalophilic Bacillus species produced hesperidin monoglucoside and a series of its oligoglucosides by the transglycosylation reaction with hesperidin as an acceptor and soluble starch as a donor. The formation of the glycosides was more effective at alkaline pHs than at neutral or acidic pHs, because of higher solubility of the acceptor. The structure of the purified monoglucoside was identified as 4(G)-alpha-D-glucopyranosyl hesperidin by FAB-MS, alpha-, beta-glucosidase and glucoamylase treatments, and methylation analysis. The solubility of both hesperidin mono and diglucoside in water was about 300 times higher than that of hesperidin, and they were found to have a stabilizing effect on the yellow pigment crocin, from fruits of Gardenia jasminoides, against ultraviolet radiation.