Črtomir Tavzes

Institute for the Protection of Cultural Heritage of Slovenia · Research Institute

Fungal melanin staining is a problem on many cultural objects, ranging from the French Palaeolithic cave at Lascaux to books and papers in museum collections. Melanin, because it is insoluble and resistant to bleaching, may leave behind undesirable stains long after the fungal infestation has been controlled. Research into removal of melanin stains...

Raman mapping can provide molecular information to complement data derived from other analytical techniques in works of art and other objects of cultural significance. Raman mapping can be performed using a motorized microscope stage that moves a sample or an object point by point in two spatial directions. The method can be used both noninvasively...

Black poplar wood, diethylene glycol (DEG), and sulphuric acid as a catalyst were used as starting reactants for liquefaction. Optimal conditions for liquefaction were established: reaction temperature 150 degrees C, reaction time 95min, ratio of wood:DEG=1:5 and 3% of sulphuric acid addition. The liquid mixture obtained by the liquefaction was com...

ELISA (Enzyme-linked ImmunoSorbent Assay), as one possible application of antibody-based methods, has proved to be a good candidate for the determination of proteins in works of art due to the low limit of detection, high sensitivity (in the nanogram range), specificity and micro invasiveness of required sampling. Despite the advantages of this met...

Consumer awareness, strengthened by legally imposed green constraints, has led to the need for the safe return of products from the field, as well as more environmentally friendly products. As a result, logistics planning must now consider both forward and return flows of products, parts, subassemblies, scrap, and packaging. Reverse logistics is th...

The primary purpose of the study, as part of the planned conservation work, was to uncover all aspects of autochthonous biofilm pertaining to the formation of numerous deterioration symptoms occurring on the limestone Rožanec Mithraeum monument in Slovenia. Using state-of-the-art sequencing technologies combining mycobiome data with observations ma...

Almost 200 nations, including the European Union, have signed the Paris Agreement that aims to limit the temperature rise to 1.5 °C above pre-industrial levels by reducing greenhouse gas (GHG) emissions. To meet this target, a significant decrease in GHG emissions by 2030 and net zero by 2050 is necessary. To determine the role of wood products in...

Forest-based industries produce huge quantities of bark during their primary processing activities. In Nordic pulp and paper industries, where a wet debarking process is used for bark removal, toxic debarking water and bark press water are produced as a by-product. However, polyphenols represent an important fraction of the debarking water and bark...

The fungal community of biodeteriorated 17th century mural paintings within the nave and altar portion of the old Church of the Holy Ascension (Veliki Krčimir, Nišava District, Serbia) has been studied via an array of microscopic analyses in order to detect actively growing fungi and assess their potential damage to the painted layer and mortar. In...

Olive mill waste water (OMWW), a by-product created during the processing of olive oil, contains high amounts of polyphenolic compounds. If put to further use, these polyphenolic compounds could be a valuable resource for the speciality chemical industry. In order to achieve this, isolation of the polyphenolic compounds from OMWW is needed. Several...

More than one hundred ninety nations, including the European Union, have signed the Paris Agreement to limit the temperature increase to 1.5 °C above pre-industrial levels. Meeting these conditions requires a steep decline in greenhouse gas (GHG) emissions by the year 2030 and zero GHG emissions by 2050. In this study, we investigated the role that...

Olive oil production using three-phase decanter systems creates olive oil and two by-products: olive mill wastewater (OMWW) and pomace. These by-products contain the highest share of polyphenolic compounds that are known to be associated with beneficial effects on human health. Therefore, they are an attractive source of phenolic compounds for furt...

Abstract: More than one-hundred-ninety nations, including the European Union, have signed the Paris Agreement to limit temperature increase to 1.5 °C above pre-industrial levels. To meet these conditions requires a steep decline in greenhouse gas (GHG) emissions by the year 2030 and zero emissions by 2050. In this study, we investigated the role th...

Plant pathogenic bacterium Xanthomonas campestris pv. campestris (Xcc) was recently described as a pathogen of winter oilseed rape in Serbia. A metabarcoding approach was used to study bacterial community composition changes in the phyllosphere and rhizosphere of different winter oilseed rape types (lines, cultivars, and hybrids) naturally infected...

Advanced imaging techniques can noninvasively characterise, monitor, and evaluate how conservation treatments affect cultural heritage objects. In this specific field, hyperspectral imaging allows nondestructive characterisation of materials by identifying and characterising colouring agents, binders, and protective coatings as components of an obj...

Sustainable approaches for retrofitting buildings for energy efficiency are becoming necessary in a time when the building sector is the largest energy consumer. Retrofitting building stock is effective for reducing global energy consumption and decreasing resource exploitation. Less developed EU member states and neighboring developing countries s...

Full-text can be found here. The valorization of olive pomace through the extraction of phenolic compounds at an industrial scale is influenced by several factors that can have a significant impact on the feasibility of this approach. These include the types and levels of phenolic compounds that are present, the impact that seasonal variation and c...

Generated fire effluents are toxic and responsible for the majority of fire deaths and injuries. Therefore, measures of fire safety and the assessment of toxic effects of fires on humans, which are the key factors to assess fire hazards, have been researched in the last decades. However, it is more and more recognized that there is also a need to a...

System of prefabricated modules installed on the existing building envelope is one alternative solution for deep energy refurbishment of buildings in the European Union. It allows thermal upgrade installation of new parts in the HVAC system. Moreover, some elements of the envelope can be made of renewable materials. This research compares the resid...

Japanese armour (Fig. 1), which has been a part of an important collection of the National Museum of Slovenia since 1961, consists of different parts such as helmet (kabuto), neck guard (nodowa), facemask (menpo), chest plate (do), armoured sleeves (kote), armoured shorts (haidate), etc. In this work, its material composition was defined by means o...

Analysing the materials present in artworks presents unique challenges, due to their chemical complexity, interactions between the components of the mixture, alteration, exposure to human intervention, etc. Among materials present in art objects, proteins have been widely used, generally in the form of adhesives, coatings, but especially as binding...

Objects of cultural heritage, which are inappropriately preserved, are often subjected to uncontrolled decaying. Environmental influences (e.g. humidity, temperature, air pollution, etc.) affect not only chemical composition, but can also interfere with physical properties and in some cases offer suitable conditions for biological overgrowth (e.g....

Liquefied wood-based polyurethane wood coatings of an aesthetically acceptable light colour were prepared and characterised. Liquefied black poplar wood was obtained by solvolysis in a polyethylene glycol/glycerol mixture, and it was bleached with hydrogen peroxide. The bleaching treatment converted liquefied wood from a dark brown to a yellowish p...

Proteins have been widely used, generally in the forms of adhesives, coatings but especially of binding media for colouring materials, where the most commonly used were casein (milk), ovalbumin (egg white), or collagen (bone, skin). Analysing the binding media in artworks presents unique challenges, due to their chemical complexity, interactions be...

The aim of this study was to develop polymers in a liquid solution, from renewable bio-resources, usable as intermediate materials in the preparation of plastics, adhesives or coatings. The liquefaction of cork with glycerol was investigated at 150 degrees C, 180 degrees C, and 200 degrees C under acidic (sulphuric acid) or alkaline conditions (sod...

The object of this paper is to study the ability of four white-rot fungi (Trametes versicolor, Hypoxylon fragiforme, Chondrostereum purpureum, and Pleurotus ostreatus) and one brown-rot fungus (Gloeophyllum trabeum) to degrade the organochlorine insecticide lindane in liquid cultures. The evaluation of lindane biodegradation was performed using two...

The liquefied biomass resulting from various liquefaction processes developed up to now is of a dark-brown or even black colour. This intense colouration could limit its use as an intermediate for the production of bio-based materials (plastics, adhesives or coatings) due to aesthetic reasons. In this study, bleaching of liquefied wood using variou...

Five major types of lichen were discovered in the investigated specimens from Dornava Manor. All these lichens and/or their combinations are considered common lichenous overgrowth for the region and its climate. For all of the positively identified lichen species, it is common that they are found on a wide variety of calciferous or base-rich substr...

The management of natural resources is a subject that often arises when sustainable development is considered. Use of wood products results in lower GHG emissions into the atmosphere than competing products and thus a lower overall environmental impact. As renewable biological raw material, wood is used in numerous applications, and is therefore ga...

Melanin is chemically and by physical characteristics very similar to lignin, a major constituent of wood, and therefore ligninolytic enzymes of white-rot fungi were tested for their ability to selectively degrade melanin. Melanin degradation was studied both in liquid suspensions of melanin and on melaninised paper samples. Liquid suspension sampl...

Microbial mechanisms of lignin degradation may be utilised for solid-state fermentations other than biopulping, during which the selective conversion of lignin is required. The current paper reviews current work into selective lignin conversion, with emphasis on the contributions made by our research group, which consists of researchers from five d...

The efficiency of a low molecular weight delignification system consisting of copper (II) and hydroperoxides in the presence of the copper coordinating compound 4-aminopyridine (4-AP) was evaluated using oxygen bleached kraft pulp (OKP). A kappa number reduction of 30% at pH 11.3 could be achieved by one single copper/4-AP/H2O2 stage. Consecutive t...

Tavzes, Č., Pohleven, F., Pohleven, J., Janišek, M., Koestler, R.J., 2002. Effect of asphyxiation on wood decay fungi treated with argon and nitrogen gas. The International Research Group on Wood Preservation. Document, No.IRG/WP 02-10452 Paper presented at the 33rd Annual Meeting, Cardiff, UK May 13-17th 2002. IRG Secretariat, SE-100 44, Stockholm...

The effects of low-oxygen conditions, achieved with either argon or nitrogen gas, on the viability of wood-decay fungi Coniophora puteana and Antrodia vaillantii, grown on artificial growth medium, were tested. Initial tests for viability were run after 1, 2, 3 and 4 weeks of exposure to low oxygen conditions, at oxygen levels in the vessels mainta...

Microbial mechanisms of lignin degradation may be utilised for solid-state fermentations other than biopulping, during which the selective conversion of lignin is required. The current paper reviews current work into selective lignin conversion, with emphasis on the contributions made by our research group, which consists of researchers from five d...