Short Communication On-site hydrolytic enzymes production from fungal co-cultivation of Bermuda grass and corn cob Aldo Amaro-Reyes a , Jorge Gracida a , Nelson Huizache-Peña b , Norberto Elizondo-García c , José Salazar-Martínez c , Blanca E. García Almendárez a , Carlos Regalado a,⇑ a Universidad Autónoma de Querétaro, Centro Universitario, Cerro de las Campanas s/n Col. Las Campanas, 76010 Querétaro, Querétaro, Mexico b Universidad Politécnica de Pachuca, Carretera Pachuca-Ciudad Sahagún Km. 20, Ex-Hacienda de Santa Bárbara, 43830 Zempoala, Hidalgo, Mexico c Forrajera Elizondo, S.A. de C.V., Carlos Salinas de Gortari 600, Apodaca Centro, 66600 Apodaca, Nuevo León, Mexico highlights  On-site enzymes were produced from fungal fermentation of Bermuda grass and corn cob.  Fermented forage showed high cellulolytic, amylolytic and xylanolytic productivities.  Fermented forage showed potential in ruminal digestibility improvement of animal feed.  On-site enzymes production could represent economical availability of animal feed. article info Article history: Received 11 March 2016 Received in revised form 14 April 2016 Accepted 15 April 2016 Available online 19 April 2016 Keywords: On-site enzymes production Hydrolytic enzymes Co-culture Aspergillus niger Trichoderma reesei abstract Solid state fermentation (SSF) is used to produce industrial enzymes. The objective of this study was to use a co-culture of Aspergillus niger GS1 and Trichoderma reesei, grown on a mixture of Bermuda grass and corn cob to obtain fermented forage (FF) rich in hydrolytic enzymes, as a value added ingredient for ani- mal feed. FPase, amylase and xylanase productivities (dry matter, DM) were 8.8, 181.4, and 42.1 U g 1 h 1 , respectively (1 U = reducing sugars released min 1 ), after 12–16 h of SSF with C/N = 60. Cellulose, hemicellulose and lignin decreased 1.6-, 2.7- and 1.9-fold (DM), respectively. In vitro ruminal and true digestibility of DM was improved 2.4- and 1.4-fold. Ruminal digestion of FF reduced 1.32-fold the acetate:propionate ratio, which may reduce the environmental impact of ruminants feeding. On-site hydrolytic enzymes productivity using SSF without enzymes extraction could be of economic potential for digestibility improvement in animal feed. Ó 2016 Elsevier Ltd. All rights reserved. 1. Introduction Feed grains are widely used energy sources in ruminant diets, but their price keeps steadily increasing due to higher demand. Ruminal digestibility of forage cell walls ultimately limits nutrient availability due to harsh environmental conditions faced by micro- bial population, resulting in reduced fiber digestion (Sujani and Seresinhe, 2015; Tadele and Animut, 2015). The use of exogenous fibrolytic enzymes can increase forage utilization leading to animal weight gain, despite some controversial research reports (Sujani and Seresinhe, 2015). Additionally, on-site hydrolytic enzymes production by solid state fermentation (SSF) on forage as substrate, can be achieved by co-culture of fungi (Farinas, 2015). Bermuda grass (Cynodon dactylon), a typical warm-season perennial turf-grass mixed with corn cobs may be used to favor both gas and mass transfer due to their inherent structural porosity. Cellulases, xylanases and amylases are a group of enzymes which catalyze hydrolysis of hemicellulose material and starch mostly into glucose and xylose (Farinas, 2015; Sahnoun et al., 2015). This work addresses the impact of using a co-culture of Aspergil- lus niger GS1 and Trichoderma reesei, by means of SSF on a mixture of Bermuda grass and corn cob, to obtain fermented forage rich in hydrolytic enzymes, as potential ingredient for animal feed. 2. Materials and methods 2.1. Biological material A. niger GS1 (National Center for Biotechnology Information, NCBI No. GU395669) and T. reesei (NCBI No. AF510497) were used http://dx.doi.org/10.1016/j.biortech.2016.04.070 0960-8524/Ó 2016 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. E-mail address: regcarlos@gmail.com (C. Regalado). Bioresource Technology 212 (2016) 334–337 Contents lists available at ScienceDirect Bioresource Technology journal homepage: www.elsevier.com/locate/biortech