2 research outputs found
Biodeterioration patterns found in dammar resin used as art material
Since the middle of the XIX century, when dammar became popular in
Occident, this natural resin is one of the most used in art painting
techniques as final protective coating (varnish) as well as a component
of pictorial media. The present work is the first approach to the study
of the microbiological biodeterioration of this artistic material,
which can seriously affect the appearance and integrity of works of art
when bad conservation conditions -especially high humidity levels- take
place. 12 microorganisms, fungi and bacteria, came from collection and
from oil paintings affected by biodeterioration patterns, were
inoculated on test specimens prepared with varnish dammar. These were
incubated and analyzed by GC-MS to determine both the microbiological
capacity of growth and chemical alteration on the resin. Some of the
studied microorganisms have shown patterns of deterioration similar to
those found in works dedicated to natural or accelerated photochemical
ageing of triterpenoid varnishes
An approach to the study of the fungal deterioration of a classical art material: Mastic varnish
Mastic, one of the best natural varnishes, is frequently used as
protective and finishing layer or as component of oleo-resinous media
in paintings, both in the past and currently. However, this resin is
affected by complex deterioration processes which can change its
characteristics and thus the visual aspect of works of art. The
alteration processes caused by radiation have been widely studied, but
there is a lack of information on the biodeterioration of this natural
product. In this paper, fungi from collections as well as from oil
paintings of the Fine Arts Museum of Granada (Spain) were inoculated
onto slides covered with mastic. The samples, after an incubation
period of 15 days, were analysed by gas chromatography-mass
spectrometry (GC-MS) to identify the chemical changes undergone, and a
visual monitoring of the samples was performed to determine the
formation of mycelia onto solidified resins. Major changes were
detected in Chrysonilia sitophila, Phoma herbarum, and P. chrysogenum,
showing evidence of alteration processes caused or favoured by these
microorgamisms