[Studies on microbial factor on color change of Dunhuang mural. I. Classification of microbes on color-changed mural and property of some typical species].

Microbial strains were isolated from 51 typical color changed samples of mural in 6 grottos of Dunhuang Mogao Gretto. After identification, it is proved that belong to 6 genera of bacteria and 5 genera of mould. Bacillus, Alcaligenes and Penicillium were dominant species in all of them. In the imitative experiment, it is found that Cladosporium sp., A. niger and two strains of bacteria have a great effect on the color change of red pigment of mural and aging of sizing agent.