Mycopath (2014) 12(1): 17-23 Research Article Screening for extracellular hydrolytic enzymes production by different halophilic bacteria M. Delgado-García, C.N. Aguilar, J.C. Contreras-Esquivel and R. Rodríguez- Herrera * 1 Food Research Department, School of Chemistry. Universidad Autónoma de Coahuila. 25280, Coahuila, México. * Corresponding author’s email: raul.rodriguez@uadec.edu.mx Abstract At the present time, some industrial processes require enzymes able to act under extreme physicochemical and environmental conditions. Typical enzymes may be degraded when are acting under high temperature, extreme acidic or alkaline pH, high pressure, etc. Halophilic microorganisms have capacity to support high salt concentration in the medium, allowing live under high ionic strength, low aqueous activity, organic solvents, etc., and their enzymes also have these properties. This study describes the extracellular hydrolytic enzyme production of eight moderately halophilic bacteria, isolated from the semi-desert region of Coahuila Mexico. The evaluated enzymes were amylases, proteases, cellulases, xylanases, DNAases, pectinases, chitinases and lipases using culture media with 14% NaCl (w/v). Halo formation was the method used to detect the positive extracellular enzyme production. Most of the strains were able to produce amylases, cellulases, pectinases and xylanases. Where, xylanases were those with the greatest intensity halo formation, and may have potential to be used for bio-catalytic processes. Keywords: Biotechnological applications, halophilic hydrolases, hydrolytic halos, xylanases. Introduction the microbial enzymes are very important; because some products can be obtain in minor time, with better quality, but specially generating eco-friendly processes, reducing the toxic sub- products (Bhalla et al., 2011). According to BCC Research (http://www.bccresearch.com/), the global enzyme market was about $3.9 dollar billions at 2011, and it is estimated about $6.1 dollar billions at 2016. These huge sales of industrial enzymes are attributed to different causes being a one of them, the enzymatic instability to extreme operational conditions, which may generate low processes productivity (Kumar, 1998; Rozzell, 1999; Schoemaker et al., 2003). For this reason, search for new enzymes able to support diverse extreme conditions is needed. Some studies have focused on microorganism’s extreme enzymes. One characteristic of extreme-enzymes is the capacity for supporting more than one extreme condition (high temperature, high pressure, high salt concentration, acid or alkaline pH, low aqueous activity etc) (Gomes and Steiner, 2004; Bowers et al., 2009; Marhuenda-Egea and Bonete, 2002; Karan et al., 2012). Thermophilic are one of the most studied feature of extreme microorganisms, however recently, scientists have focused on other extreme microorganisms such as halophiles. These microorganisms support high ionic strength. Their enzymes have a structure and catalytic properties that improve its capacity under extreme conditions, these features are very important for their biotechnological potential and industrial process applications (Karan et al., 2012). Moderately and extreme halophilic bacteria and Archaea are the best halophilic enzyme producers. However, although Archaea are able to support more salt concentration (>10 %), these are not widely studied because their enzymes lose easily their activity under low ionic strength, and separation methods are ineffective to high salt concentration, preventing their characterization and purification (Madern et al., 2000; Ventosa et al., 2005). In contrast, moderately halophilic bacteria are able to produce enzymes which are more active under medium and high salt concentrations, but also are stable and active under absence of salt. For this reason, the moderately halophilic enzymes are more studied for their biotechnological potential (Ventosa et al., 1998). Some halophilic enzymes have been studied for their diverse industrial applications, e.g. Micrococcus varians subs. halophilus nuclease is used to produce guanilic-5´acid and inosinic- 5´acid as flavor additives (Kamekura and Onishi, 1974). a halophilic enzymes group (proteases, lipases, ribonucleases) used under sauce fermentation which elevate nitrogen content and volatile fat acids has been evaluated (Kanlayakrit