Detection and Identification of the Latent Microorganisms in the Corrosion Layers of Ancient Bronze Mirrors

• Yokota Masaru

  Faculty of Art and Design, University of Toyama

• Tochihara Misako

  Analysis & Characterization Division, Chiba Works, JFE Techno-Research Corporation

• Tanaka Masao

  Food and chemistry department, Chiba Industrial Technology Research Institute

• Nagae Takekazu

  Faculty of Art and Design, University of Toyama

• Mifune Haruhisa

  Faculty of Art and Design, University of Toyama

• Sugaya Fuminori

  School of Human Cultures, The University of Shiga Prefecture

• Miyahara Shinichi

  1st Dept. Researc, Archaeological Institute of Kashihara

• Shimizu Yasuzi

  1st Dept. Researc, Archaeological Institute of Kashihara

Bibliographic Information

Other Title

• 古代青銅鏡の腐食層内に潜伏する微生物の検出とその同定
• コダイ セイドウキョウ ノ フショクソウナイ ニ センプクスル ビセイブツ ノ ケンシュツ ト ソノ ドウテイ

Abstract

  On an ancient bronze mirror, we carried out a scanning electron microscopic (SEM) examination of fractured corrosion layers, a biological microscopic observation of a gram-stained sample and DNA analyses of the samples removed from corroded sites.<br>    From these scientific and technical researches, we obtained the following results.<br>    Fine particles about 2 μm in length were confirmed in the corrosion layer by the SEM observation. Microorganisms of the same size were observed in the gram-stained sample removed from the corrosion layer through a biological microscope. From these results, fine particles observed under the SEM should be considered as microorganisms. A lot of fine particles were confirmed especially in the corroded sites by the SEM observation. So (certain kinds of) microorganisms may have played a role in the corrosion (deterioration) of the ancient bronze mirrors while the mirrors were buried in soil.<br>    From the base sequences obtained by DGGE analysis, two kinds of microorganisms were confirmed to exist in the corrosion layer of the ancient bronze mirror. One is 97.4% homologous to the 16S rDNA of the uncultured bacterium (Accession number: AY 053488). It was also highly homologous to the sequence derived from the 16S rDNA of the Xanthomonadaceae family such as Stenotrophomonas and Xanthomona. That is, the sequence is derived from a strain belonging to the Xanthomonadaceae family. The other base sequence is 97.4% homologous to the 16S rDNA of the Bacteroidales order such as uncultured Bacteroidales bacterium (Accession number: AY 859647). That is, the sequence is derived from a strain belonging to the Bacteroidales order.<br>    Genes of microorganisms, presumed to belong to the Acetobacter, Gluconacetobacter genuses and Fe(III)-reducing bacterium, Shewanella algae were detected from the base sequence analysis by cloning.<br>    From the results above, microbial activity is assumed to be high around the ancient bronze mirrors. The corrosion mechanism of bronze mirrors seems complicated, but a several types of microbes which possibly corrode bronze mirrors were verified.<br>

Journal

• Journal of the Japan Institute of Metals and Materials

  Journal of the Japan Institute of Metals and Materials 72 (2), 111-116, 2008

  The Japan Institute of Metals and Materials

Keywords

• ancient bronze mirror
• corrosion in clay
• deterioration of metallic cultural resource
• scientific investigation
• microorganism
• DNA analysis
• DNA cloning

Details

• CRID: 1390001206478827776
• NII Article ID: 10021149691
• NII Book ID: AN00187860
• DOI: 10.2320/jinstmet.72.111
• ISSN: 18806880
• ISSN: 24337501
• ISSN: 00214876
• NDL BIB ID: 9371304
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I9371304
• Web Site: https://www.jstage.jst.go.jp/article/jinstmet/72/2/72_2_111/_pdf
• Text Lang: ja
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
  • KAKEN
• Abstract License Flag: Disallowed