The digestive juice can be used as-is, or in a purified form. The efficiency of Helix pomatia digestive juice to hydrolyze isoflavone glycosides was established by incubating in vitro 100 μg each of daidzin and genistin with 0.1 mL of Helix pomatia digestive juice suspended in 10 mL of 0.05M sodium acetate buffer, pH 4.5 at 37° C. Before adding the enzyme/buffer mixture, it was passed through a solid-phase C18 Bond Elut cartridge to remove residual amounts of isoflavones that we have previously found to naturally occur in this enzyme preparation. The concentrations of daidzin and genistin remaining, and daidzein and genistein formed during incubation were determined by HPLC on aliquots of the mixture removed at timed intervals over the next 24 hours.
