Changes in autantio-obtusin and glucoaurantio-obtusin content in Cassiae Semen via treatment with a crude enzyme extract from Aspergillus usamii

Cassiae Semen (seeds of Cassia tora) showed a remarkably different HPLC chromatogram after being treated with a crude enzyme extract from Aspergillus usamii. Increased and decreased compounds were identified as aurantio-obtusin and glucoaurantio-obtusin, respectively. The aurantio-obtusin content reached its maximum level (133.58±0.39 μg/mg extract) after being incubated for 50 min at 37°C, whereas the inactivated crude enzyme-treated control remained unchanged (54.13±1.33 μg/mg). On the other hand, the glucoaurantio-obtusin content decreased by less than one-third (51.09±1.63 μg/mg) of the untreated control (143.19±2.12 μg/mg), suggesting that an increase in aurantio-obtusin content originated from the enzymatic cleavage of its glucoside glucoaurantio-obtusin.