توليد اتانول و كيتوزان توسط مورفولوژي هاي مختلف قارچ موكورهيماليس از كاه برنج

چكيده انگليسي :

Ethanol and Chitosan Production by Different Morphologies of Mucor hiemalis from Rice Straw Hamid Reza Beheshti hr beheshti@ce iut ac ir 2014 01 15 Department of Chemical Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisors K Karimi karimi@cc iut ac ir A Zamani zamani akram@cc iut ac irAbstractBioethanol as a clean and renewable fuel is considered as good alternative to replace fossil fuels Bioethanolcan be produced from a variety of feedstocks including sugar starch and lignocellulosic based materials Ricestraw is one of the most abundant agricultural wastes in the world In the present work bioethanol productionfrom rice straw by different morphologies of Mucor hiemalis was studied The rice straw was treated withsodium hydroxide and phosphoric acid with or without ultrasonication prior to enzymatic hydrolysis Thealkali pretreatment was performed with 12 sodium hydroxide solution at 0 C for 3 hours while phosphoricacid pretreatment was carried out at 50 C for 30 minutes The pretreatments resulted in improvement of theenzymatic hydrolysis and the glucose theoretical yield of 76 93 was obtained The best hydrolysisperformance was achieved by ultrasonic assisted sodium hydroxide pretreatment 93 glucose theoreticalyield The dimorphic fungus M hiemalis is a dimorphic fungi which belongs to the class of Zygomycetes Based on the results of current study M hiemalis showed appropriate ability to produce ethanol from rice strawhydrolysate The biomass of the M hiemalis contains appreciable amounts of chitosan and is cosidered as goodresource to produce this useful biodegradable polymer In the present study induction of differentmorphological growth of M hiemalis was firstly investegated The results showed that inoculation of low sporeconcentrations 1 4 105 spores mL and availability of oxygen induced the fungus to grow in the purelyfilamentous form while inoculation of higher spore concentrations 10 20 105 and 8 106 spores mL underaerobic conditions caused the fungus to grow in the mostly filamentous and mostly yeast like forms respectively In addition with high spore concentrations 8 106 spores mL and application of anaerobicconditions the morphology was purely yeast like More researches revealed the ability of all morophologicaltypes of M hiemalis to produce ethanol from different hydrolysates of rice straw Maximum ethanol productionyield of 0 44 g ethanol g glucose by purely yeast like morphology of M hiemalis was obtained from thehydrolyzate of ultra assisted sodium hydroxide pretreated rice straw Furthermore only negligible increase inethanol and glycerol yield for purely yeast like cells than the other morphologies was observed 0 35 0 44 gethanol g glucose depending on the pretreatment method Beside the yield of production of ethanol andglycerol from rice straw hydrolysate by different morphologies of M hiemalis biomass yield protein phosphate and chitosan content of the cell wall were also examined The yield of biomass of yeast like cellsunder aerobic conditions was more than filamentous cells and biomass of this morpholgy had higher proteincontent while it s phosphate 0 063 0 071 g phosphate g AIM and chitosan 0 184 0 242 g GlcN g AIM contents were less than filamentous type 0 089 0 107 g phosphate g AIM 0 297 0 341 g GlcN g AIM respectively Keywords Chitosan Ethanol Morphology Mucor hiemalis Phosphoric acid Pretreatment Rice straw Sodium hydroxide

بهشتي، حميدرضا

توليد اتانول و كيتوزان توسط مورفولوژي هاي مختلف قارچ موكورهيماليس از كاه برنج

پيش فرآوري , هيدروكسيد سديم , اسيد فسفريك