Journal of Scientific & Industrial Research Vol. 64, October 2005, pp. 767-770 Production of fungal cellulases by solid state bioprocessing of groundnut shell wastes Ashish Vyas* and Deepak Vyas Lab of Microbial Technology and Plant Pathology, Department of Botany, Dr Hari Singh Gour University, Sagar 470 003 Received 22 March 2005; accepted 15 July 2005 Groundnut shell was found to be potent inducer of cellulases by Aspergillus terreus, A. nidulans and Trichoderma viride in solid-state fermentation. Combination of A. terreus and Trichoderma viride was best for cellulase production. Keywords: Solid state fermentation, Cellulase, Endoglucanase (E.C 3.2.1.4), Exoglucanase (E.C 3.2.1.94), Groundnut shell Introduction Solid State Fermentation (SSF) is the growth of microorganisms on moist solid materials in absence of free flowing water 1,2 . SSF conditions are especially suitable for the growth of fungi, known to grow at relatively low water activities; however, growth of bacteria, yeasts and filamentous fungi on solid substrates for SSF raises the possibility of using them in bioprocesses 3 . The present work evaluates cellulase production in monoculture and co culture conditions by cellulolytic fungi on groundnut shell (GS) under SSF condition. Materials and Methods Microorganisms Aspergillus terreus, A. nidulans and Trichoderma viride, isolated from wide diversity of habitats, were found positive for cellulase activity 4-6 . All fungi were maintained on PDA slants at 4 °C. Substrate Shells (1 kg), collected from local suppliers in and around Sagar district, were powdered and soaked in water (5 l) for 18 h 7 . Excess water was drained off and powder was dried at 70°C for 24 h. The powder was then sieved (100 μm mesh) and kept at room temperature. Pretreatment of GS Dried powdered shell (100 g) was soaked in 1N NaOH (500 ml) for 24 h. After treatment, excess alkali was decanted and powdered shell was repeatedly washed with distilled water till it reached neutral pH and then dried over night at 60 °C 8 . Inoculum Preparation Fungal cultures were grown on PDA slants and the spores were harvested aseptically from 5 d old PDA slants (Table 1). Sterile distilled water (2 ml) was added to each fungal agar slant and shaken vigorously for preparing uniform suspension, which was used as inoculum 9 . Enzyme Production in Solid State Fermentation (SSF) Pretreated GS (10 g) was moistened with Mandel and Reese medium 10 (Proteose peptone, 1.0; (NH 4 ) 2 SO 4 , 1.4; KH 2 PO 4 , 2.0; NH 2 -CO-NH 2 , 0.3; MgSO 4 .7H 2 O, 0.3; CaCl 2 , 0.3; FeSO 4 .7H 2 O, 0.005; MnSO 4 .H 2 O, 0.0016; ZnCl 2 , 0.0017; distilled water, 1000 ml; pH: 5.3) to initial moisture content (50 %) and autoclaved in 250 ml flasks at 121°C for 1 h. After cooling, flasks were inoculated with fungal inocula. The contents in the flask were mixed thoroughly to ensure uniform distribution of the inoculum and flasks were incubated in slanting position at 28±1°C for 21 days. The samples were withdrawn after 7 th , 14 th , 21 st day of incubation and assayed for enzymatic activity. The enzyme was extracted with the phosphate buffer (pH 5) applying substrate: buffer (1:10) employing a simple contact method 11 . The enzyme extract was filtered through whatman filter paper no. 1 and centrifuged at 9500 rpm for 20 min at 4°C. The clear supernatant obtained was used in enzyme assay. Endoglucanase and exoglucanase activity was measured 12 in IU. __________ *Author for correspondence Tel: +91-7582-264869; Fax: +91-7582-265067 E-mail: vyas_unisagar@yahoo.co.in