Increase of Aurantio-Obtusin Content in Cassiae Semen by the Treatment of Crude Enzyme Extract from Aspergillus kawachii

“Suchi“, a kind of processing technique, have been used for reducing toxicity or changing medicinal efficacy of oriental crude drugs. The techniques, however, are rarely used nowadays due to their complexity and lack of scientific backgrounds. On the other hand, food processing techniques such as heating, extrusion, and enzyme treatment (fermentation) might be applied to oriental crude drugs in order to increase the contents and/or to change the chemical structure of biologically active compounds.

The effect of processing on chemical compositions of fifty commonly used oriental crude drugs was investigated. As a result, an increased peak was found in HPLC analysis of Cassiae Semen which was treated with enzyme solution from Aspergillus kawachii. The increased peak was isolated by column chromatography and identified by spectroscopic analysis as an anthraquinone, aurantio-obtusin. At 37°, the obtusin reached its maximal level at 50min after on set of the crude enzyme treatment (before treatment: 24.55±2.06mg/g, after treatment: 72.31±1.58mg/g). The crude enzyme extract from A. kawachii has been known to have a strong glycosidase activity, therefore aurantio-obtusin appeared to be produced by the cleavage of its corresponding glycosides. Obtusin has been known to have ant-mutagenic, anti-phytopathogenic activity. Above results suggested that the simple processing might be useful for increasing the contents of biologically active substances in oriental drugs.