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We report a continuous flow process for biaryls consisting of a packed-bed reactor and a rapid extraction system. Continuous extraction with supercritical carbon dioxide (scCO2) was applied to a Suzuki–Miyaura...

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.

Along with increasing relevance of rare earth (RE) elements in industrial technology, the risk of their environmental release and occupational exposure on human health is of concern. Although many toxicological studies were reported for REs, it is not known how they affect DNA repair. In this study, the effects on DNA repair of all RE ions except radioactive promethium (Pm) were studied. Human lymphoblastoid WTK1cells were irradiated to UV followed by 2h exposure to each RE with and without DNA repair inhibitor cytosine-1β-D- arabinofuranoside (araC), and then single strand breaks (SSBs) were detected by the comet assay. UV-induced pyrimidine dimers are removed by nucleotide excision repair (NER) which consists of recognition of the DNA lesion, excision of a 24–32 nucleotide stretch containing the lesion by dual incision of the damaged DNA strand on both sides, and re-synthesis of the resulting gap by DNA polymerase, and ligation of the nick. SSBs are generated in the incision step of nucleotide excision repair (NER) and disappear in the re-synthesis step of NER. Seven REs, Yb, Lu, Dy, Er, Sc, Pr, and Ce, enhanced comet positive response without araC but not with araC, suggesting that araC is antagonistic to the 7 REs. Since araC inhibits re-synthesis of NER, these seven REs would inhibit the re-synthesis step of NER. Six REs, Tm, Sm, Tb, Gd, Eu, and Y suppressed comet positive responses with and without araC, suggesting that they decreased comet assay detectable SSBs. Therefore, these 6 REs are considered to inhibit the incision step of NER. Only La decreased tail length without araC but increased with araC, suggesting that La increased comet assay detectable SSBs and that only La would enhance the incision step of NER. Neither Nd nor Ho affected tail length with or without araC.