CORRELATION TESTS BETWEEN RELATIVE LIGHT UNIT AND COLONY FORMING UNIT FOR IMPROVING ADENOSINE TRIPHOSPHATE BIOLUMINESCENCE ANALYSIS IN BACTERIAL CONSOLIDATION TREATMENTS ON PALAEONTOLOGICAL HERITAGE.

In this article bacterial carbonate mineralization treatments are proposed as a novel strategy for decayed fossils and palaeontological heritage conservation; specifically, by means of inoculation of Myxococcus xanthus, a bacterium of proven effectiveness in ornamental stone bioconsolidation. Bioconsolidation treatments can be very effective, stable, non-toxic, environmentally friendly, and chemically compatible with fossil heritage. The method reproduces what nature has been doing for millennia with fossils that have been permineralized by bacterial calcium carbonate precipitation. There is, however, some concern that bacterial inoculation could lead to the growth of undesirable microbiota which could subsequently damage the fossil substrate. Because of this, the use of bacteria on heritage items must be meticulously monitored and analysis strategies should be carried out to detect bacteria viability during and after treatments. For this purpose, Adenosin Triphosphate (ATP) assay is proposed in this article as a fast, affordable, portable, and easy-to-use system for conservators. Since ATP assay results are relative and difficult to relate to Colony Forming Unit (CFU), this study aims to improve their applicability by examining the correlation between ATP analysis and total viable bacteria count in the specific case of Myxococcus xanthus. This research provides reference and correlatable data to obtain an approximate estimation of Myxococcus xanthus viable bacterial colonies based on Relative Light Unit (RLU) data.