EFFECTIVE HYDROLYSIS OF HESPERIDIN TO PREPARE HESPERETIN 7-GLUCOSIDE

An efficient method of hydrolyzing hesperidin to prepare hesperelin 7- glucoside (Hesperetin monoglucoside; HMG) was established. Hesperidin was first converted from its flavanone form to the chalcone form under alkaline conditions, and then hydrolyzed with HCl in the presence of a water-soluble solvent such as isopropyl alcohol (IPA), n-propyl alco hol, ethyl alcohol (EtOH) and methyl alcohol. When the reaction mixtur e containing optimal concentrations of 6% hesperidin, 20% IPA and 1.5 N HCl was heated for 15 min in a boiling water bath, the maximum amoun t of HMG were accumulated. HMG can be precipitated and efficiently rec overed by dilution and evaporation to lower the IPA concentration. The solubility of crude HMG against distilled water, hot water and EtOH w as 42.5, 12.5 and 40.7 times higher than that of reagent grade hesperi din, respectively.