저널

Ancient cultural heritage made up of wood and organic fibers have been easily disintegrated or decomposed by various microorganisms like bacteria and fungi. Here, we demonstrate the effectiveness of an atmospheric pressure plasma jet (APPJ) system to sterilize the microorganisms in tangible cultural heritage. We collected several specimens from the surface of ancient documents and wooden artifacts. Finally, two bacteria and two fungi were prepared and sterilized using the APPJ treatment. The APPJ system is beneficial to its simple apparatus, quick operation time, and cost-effectiveness. Bacteria were almost sterilized within only 1 min treatment using 15 % O2 and applied bias voltage of 100 V. In case of the fungi, sterilization rate reached over 83 % but difficult to reach over 90 % even 10 min treatment. According to the plasma diagnostics using optical emission spectroscopy, it was found that the reactive oxygen species such as OH groups are critical for sterilization of microorganisms. Although further efforts should be performed, we believe that efficient sterilization could be realized by the simple, quick, and portable APPJ treatment system.

Ancient cultural heritage;Sterilization;Atmospheric pressure plasma jet;Optical emission spectroscopy;Reactive oxygen species;