Isolation and characterization of actinomycetes from Mural paintings of Snu- Sert-Ankh tomb, their antimicrobial activity, and their biodeterioration

A total of 35 actinomycetes were isolated from the surface of mural paintings of snu- sort- ankh in El Leasht, Egypt during four seasons all over 2016-2017. In 2009 this tomb was deteriorated by "Aspergillus niger, A. flavus, Fusarium moniliforme, Alternaria alternate, Rhizopus stolonifera, Bacillus subtilis, Bacillus cereus, and micrococcus iuteus." In 2017 the isolation of swabs presents only Aspergillus niger and about 35 actinomycetes classified to three different groups "Streptomyces, Nocardia, and Micromonospora" only five species belong to Streptomyces group showed antimicrobial activity against the previous microorganisms. These actinomycetes were identified according to their sequences in the GenBank to "Streptomyces spectabilis, S. alborgriseolus, S. globsus, S. corchorstt, S. ambofactens." In the other hand, the pigments of the wall paintings of the tomb (Egyptian blue, Egyptian green, Goethite) that analyzed by SEM-EDX, FTIR were measured by the spectrophotometer in both 2009 and 2017. The results showed that the actinomycetes could produce extracellular pigments causing a color change of archaeological pigments otherwise it helps in inhibition the growth of the previous microorganisms found in 2009. The optimization factors for increasing the antibiotic production of the Streptomyces were 3% NaCl and temperature between 30:35°c in Alkin pH (pH = 7.5).