Establishment of Optimal Conditions to Extract Bioactive Substances from Gamazumi Using Supercritical Carbon Dioxide

The fruits of Gamazumi (Viburnum dilatatum THUNB) have been previously reported to suppress the adverse effects of oxidative stress in rats.  To reduce time and cost, we attempted to establish optimal conditions for extracting bioactive components from Gamazumi fruits using supercritical carbon dioxide.  To verify whether the conventional hexane extraction may be replaced by the supercritical carbon dioxide extraction, component analysis results and antigenotoxic potential in mice were used to compare bioactivity of the supercritical carbon dioxide and hexane extracts.   At the same extraction pressure, the extraction rate was maximized when supercritical carbon dioxide with a low temperature was used, and extraction efficiency was improved.  GC/MS analysis revealed that vitamins E and stigmasterols were included in supercritical carbon dioxide and hexane extracts, and that no qualitative differences between supercritical carbon dioxide and hexane extracts were observed.  The antigenotoxic potential of Gamazumi extracts was studied in mice exposed to cigarette smoke inhalation.  Mice received single or 5 consecutive oral administrations of Gamazumi extracts at 0, 3, and 6 h prior to smoke inhalation.  Although single administration decreased nuclei tail length in the stomach when both administration and the intervals of smoke inhalation were short, five consecutive administrations decreased tail length in the lung and stomach regardless of the interval.  At short intervals, inhaled cigarette smoke and orally administered extracts may be simultaneously present in the gastric cavity, and direct reaction between cigarette smoke and extract is possible.  The antioxidant activity of Gamazumi extracts may result in antigenotoxic potential.  There were no differences in component analysis and antigenotoxic potential between supercritical carbon dioxide and hexane extracts of Gamazumi; thus, it is possible to replace the conventional hexane extraction with the supercritical carbon dioxide extraction.