Razieh Taheri, Cultural Heritage Office of the Province of Semnan, Iran
The paper will be presented by Masoumeh Madani Pour
Studying the Antifungal Properties of Satureja Khuzestaniea Essential Oil on Historical Papers
In the preservation of manuscripts with biological agents various methods have been used. But with passing time and increased awareness of the destructive effects arising from the use of chemical treatment of the objects, the environments and the users, an alternative method is now recommended.
In this paper the use of natural remedies extracted from plants to prevent damage from insects will be discussed. Thymol is a natural monoterpene phenol which can be found in the plants of the mint family Lamiaceae such as Thymus vulgaris, Marjoram, Salvia officinalis and Peppermint, in which thymol comes along with Carvacrol which has antifungal property.
Essential oils are volatile and do not include glycerol esters and fatty acids, and therefore, don’t leave durable stains. These materials are also easily accessible, non-toxic and affordable, to be used as pesticides.
In this research the effect of the essential oil of Satureja Khuzestaniea on two common previously mentioned fungi, frequently seen in cellulose material, "Aspergillus niger" and "Penicillium" was examined. The essential oil was applied to two groups of samples including two cultivated fungi species, and then, two infected documents using the fumigation method.
Different steps of the examination included distillation and extraction of the essence using Clevenger apparatus, preparing the culture medium, preparing bacterial suspensions using McFarland standard, fungi cultivation, distillation with different concentrations and fumigation and microscopic studies of the fungi.
Environmental condition of the culture medium was:
- Temperature: 20-25 ºC
- RH: 60-65 %
- Time: 24-72 h
In the first step it was revealed that the essential oil of Satureja Khuzestaniea in 4-8 % concentration didn’t stop fungal growth. Aspergillus niger grew faster than Penicillium in all the tests, due to its high resistance. The minimum inhibitory concentration (MIC) was 10 % in which or higher concentrations the vegetative and reproductive growth was stopped completely.
In the next step essential oil was used for fumigating ten samples including historical, Japanese handmade, and new machine-made paper. The historical samples were examined to trace the fungal infection in black, green and brown coloured areas and suspected samples were inoculated into culture medium containing Saboraud Dextrose Agar (SDA).
Because of the lack of enough historical samples, six more samples were prepared by inoculating the two mentioned fungi into the culture medium and sterilised paper moistened for one month at 20-25 ºC. These samples were cultivated again afterwards to examine the growth of fungi colonisation, which led to the infection of all samples.
For the next step a closed chamber was prepared for infected samples equipped by psychomotor, distilled water and 10% concentration (10 g) of essential oil.
According to the result, for disinfection of historical documents using fumigation method, 10% concentration and 10 g of above pesticide was not enough, but the suitable result was achieved in 30 % concentration (10 g) of pesticides.