Experimental study on evaluation of the efficiency of metallic nanoparticles and essential oil nanoemulsions in disinfection of microbial deterioration of historical parchment applying on a selected object

Abstract

Since early times, humans have searched for how to leave thoughts, information and knowledge behind them to other people and to future generations. Evidence of the ideological and cultural efforts of the human race can be found in historic documents, including those made of parchment. Biodeterioration is a vital factor affects aesthetic, functional and other properties of parchment and or other organic materials. The microbial degradation of parchment causes variety of damages. As a result, the parchment loses its original properties, becomes hard and brittle and differently stained. In the recent years, researchers have looked for cleaning and disinfecting methods to achieve a more selective and less invasive recovery of parchment handworks and books. A suitable disinfection method should fulfill certain requirements, such as highly effective in microorganism reduction, durable, safe and easy to handle, free of toxic, mutagenic or carcinogenic compounds after disinfection, affordable in operation and maintenance costs. The most popular disinfection methods used for historical objects include chemical and physical methods. Generally, these methods do not satisfy all the previous requirements. The search is therefore continuing for a disinfectant offering a high level of activity and prolonged antimicrobial action, which would be safe for both human health and for museum, archive and library collections. Nanoscale materials have emerged up as novel antimicrobial agents owing to their unique chemical and physical properties, the high surface area to volume ratio and characteristic reactivity with microorganisms. In this study silver and titanium dioxide nanoparticles and lemongrass and tea tree essential oils nanoemulsions were examined for their abilities to kill and inhibit the growth of four strains of microbes; three fungal and one bacterial strain isolated from historical parchment manuscript and molecularly identified and examined for their ability to hydrolyze collagen fibers of parchment.