47 ISSN 0026-2617, Microbiology, 2016, Vol. 85, No. 1, pp. 47–55. © Pleiades Publishing, Ltd., 2016. Determination of Endoglucanase Activity of Paper Decaying Fungi from an Old Library at the Ancient Medina of Fez 1 F. El Bergadi a , F. Laachari a , M. Sadiki a , S. Elabed a, b , M. H. Iraqui a , and S. K. Ibnsouda a, b, 2 a Microbial Biotechnology Laboratory, SMBA University, Faculty of Sciences and Technology, Fez, Morocco b City of Innovation, SMBA University, Faculty of Sciences and Technology, Fez, Morocco Received March 2, 2015 Abstract—Paper from an ancient library of the cultural city of Fez (Morocco) is exposed to rapid deterioration by variety of microorganisms, especially cellulolytic fungi. For this, ten isolates fungi previously isolated from historical biodeteriorated paper were screened for their ability to produce endoglucanase (CMCase), amy- lase, polygalacturonase and ligninase enzymes. The CMCase activity of cellulolytic strains was essayed in liq- uid media at 25°C for 10 days. Influence of temperature and pH were assessed for the production of CMCase by all the fungus isolated from decaying paper. The research findings from the present study demonstrate that all the tested isolates had cellulase, amylase, pectinase and ligninase activities. It was found that Mucor race- mosus PF15, Aspergillus niger, and Aspergillus oryzae exhibited the maximum endoglucanase activity in liquid medium (0.256, 0.236, and 0.216 UI/mL in descending order) for six days. Temperature profiling revealed optimum endoglucanase activity at 25 and 30°C. Maximum activity was observed at pH 5 and pH 6. Keywords: Fez, cellulolytic fungi, carboxymethyl cellulase, remazol brillant blue R DOI: 10.1134/S0026261716010021 Library documents of the city of Fez represent an invaluable treasure of Morocco. They are generally composites of different organic materials (papyrus, parchments, leather, wood, etc.), each with different possible responses to environnemental changes. How- ever, the paper is used frequently as supported materi- als of these manuscripts and books and it is too extremely vulnerable to a different external and inter- nal factors. Paper is made from pulp which in turn is made from either wood or other lignocellulosic materials (Gutleben et al., 2004). It is manly constituted of cel- lulose (Strzelczyk, 2004; Kacik et al., 2009) that is readily biodegraded by organisms (Puls et al., 2011). In fact, the paper can suffers from biodeterioration because its organic nature. A great variety of fungi and bacteria can accelerate the biodeterioration of written or printed paper with historical or economic value for humans (Cappitelli and Sorlini, 2005). Although, the fungi are the most important microbial agents (Zyska, 2002; Adelantado et al., 2005), they tolerate desicca- tion, high salt concentrations, and heavy metal com- pounds that are present in inks and pigments and are thus frequent inhabitants on paper supported docu- ments. Moreover, they are known to produce many types of enzyme, with cellulases playing a major role in their deteriorative activity as shown by numerous of authors (Fabbri et al., 1997; Rojas et al., 2009; Dalal et al., 2011). Indeed, fungi may serve as good producers of cel- lulase. For the complete hydrolysis of cellulose, three types of cellulases based on their mode of action work together: endoglucanases or carboxymethyl cellulases (endo-1,4-glucanase, EC 3.2.1.4) bring out the hydro- lysis of internal glycosidic bonds in cellulose chains, creating more terminal ends in the fragments, exoglu- canases or cellobiohydrolases (exo-1, 4-glucanase, EC 3.2.1.74) liberate glucose or cellobiose from ends of cellulose chains due to hydrolysis of terminal glyco- sidic bonds and β-1,4-glucosidases (β-D-glucohydro- lases, EC 3.2.1.21) further hydrolyze cellobiose formed as a result of synergistic action of the above two enzymes (Jarvis, 2003; Chandra et al., 2007). Fungi developing on historical paper at elevated humidity not only actively hydrolyze the cellulose but may also sporulate abundantly and change in the doc- uments aesthetics, either by discoloration by weak acids or by the accumulation of pigments that may stain its support in a phenomenon referred to as foxing (Arai, 2000). Fungal deterioration of different paper materials are well documented phenomena (Michaelsen et al., 2006; Green et al., 2008; Strlic et al., 2011; Pinheiro et al., 2011). Most commonly genera of fungi are found on biodeteriorated paper (Montemartini Corte and Zotti, 2005), however, cel- lulolytic fungi are particularly considered as serious degrading agents of bibliographic documents (Fabbri 1 The article is published in the original. 2 Corresponding author ( e-mail: Ibnsoudas@yahoo.fr). EXPERIMENTAL ARTICLES