full issue - Association of Biotechnology and Pharmacy

Current Trends in Biotechnology and PharmacyVol. 5 (1) 982-992 January 2011. ISSN 0973-8916 (Print), 2230-7303 (Online)Fermentation of Enzymatically Saccharified Groundnut shell forFuel Ethanol Production by Pichia stipitis NCIM 3498Chandra Sekhar Gajula 1 , Radhika Konakalla 1 , Chandel Anuj Kumar 1 , RavinderRudravaram 2 and Lakshmi Narasu Mangamoori 1 *1Centre for Biotechnology, JNT University, Hyderabad – 500 085, AP, India.2Celestial Labs Limited, Banjara Hills, Hyderabad – 500 034, AP, India.*For Correspondence - mangamoori@gmail.com982AbstractEthanol production was evaluated fromGroundnut shell (GS), a readily available potentialfeedstock, for production of fermentable sugars.Sodium hydroxide pretreated GS wasenzymatically saccharified (50 °C, pH 5.0, 50 h)using cellulolytic enzyme cocktail (cellulase,xylanase, β–glucosidase etc.) from a novel isolate,Aspergillus sp. RCAL-5. It showed cellulolyticenzyme production (Filter paperase (FPase) 0.86U ml -1 , Carboxy methyl cellulase (CMCase) 1.25U ml -1 , β-glucosidase 1.68 U ml -1 and xylanase4.57 U ml -1 ) after 4 days of incubation at 28 o Cusing delignified wheat bran as a carbon source.The maximum yield of monomeric sugars fromdelignified substrate was 0.64 g g -1 with asaccharification efficiency of 63.12 %. Thefermentation performance of Pichia stipitisNCIM3498 was assessed using GS enzymatichydrolysate (49 g l -1 sugars) for ethanol productionin 10 l fermenter. A maximum of ethanolproduction (19.4 g l -1 ) was obtained with a yield(0.46 g g -1 sugar utilized) and productivity (0.23 gl -1 h -1 ).Key words: Groundnut shell: Ethanol: Aspergillussp. RCAL-5: Pichia stipitis: Cellulase: EnzymaticsaccharificationIntroductionEthanol made from biomass can be anattractive, safer and clean energy option (1, 2).Among various forms of biomass, agro cropresidues are particularly well suited for energyapplications because of its large – scaleavailability, low cost and environmentally benignproduction (3, 4). An important issue regardingthe bioethanol production is whether the processis economical or not. The cost of raw materialfor ethanol production is an important parameterin establishing a cost effective technology.After recovery of groundnut pods,groundnut shell (GS) is a readily available materialworldwide for ethanol production. The alkalinemethod of pretreatment disrupts the cell wall andthus improves the amenability of enzymes topolysaccharides in the pant cell wall. Enzymatichydrolysis is an attractive approach to render themonosaccharides from lignocellulosics accessiblefor fermentation (5, 6). However, the cost ofcellulolytic enzymes accounts for about 60 % ofthe total cost of a bioconversion process (7). Inhouseenzyme production is always preferablechoice to bring down the overall cost of cellulosicethanol. Aspergillus sp. is widely known for itscapability to produce cellulolytic enzymes utilizingcheap carbon sources. Among the variousFermentation of Enzymatically Saccharified Groundnut