title: Enhanced ethanol production from Kinnow mandarin (Citrus reticulata) waste via a statistically optimized simultaneous saccharification and fermentation process.
abstract: Dried, ground, and hydrothermally pretreated Kinnow mandarin (Citrus reticulata) waste was used to produce ethanol via simultaneous saccharification and fermentation (SSF). Central composite design was used to optimize cellulase and pectinase concentrations, temperature, and time for SSF. The D-limonene concentration determined with high-performance liquid chromatography (HPLC) for fresh, dried, and pretreated biomass was 0.76%, 0.32%, and 0.09% (v/w), respectively. Design Expert software suggested that the first-order effect of all four factors and the second-order effect of cellulase and pectinase concentrations were significant for ethanol production. The validation experiment using 6 FPU gds(-1) cellulase and 60 IU gds(-1) pectinase at 37 °C for 12 h in a laboratory batch fermenter resulted in ethanol concentration and productivity of 42 g L(-1) and 3.50 g L(-1) h(-1), respectively. Experiments using optimized parameters resulted in an ethanol concentration similar to that predicted by the model equation and also helped reduce fermentation time.
authors.affiliation: Department of Grain Science and Industry, Kansas State University, Manhattan, KS 66506, USA. hari_manu@yahoo.com
authors.forename: Harinder Singh
authors.initials: HS
authors.lastname: Oberoi
authors.forename: Praveen V
authors.initials: PV
authors.lastname: Vadlani
authors.forename: Ananda
authors.initials: A
authors.lastname: Nanjundaswamy
authors.forename: Sunil
authors.initials: S
authors.lastname: Bansal
authors.forename: Sandeep
authors.initials: S
authors.lastname: Singh
authors.forename: Simranjeet
authors.initials: S
authors.lastname: Kaur
authors.forename: Neha
authors.initials: N
authors.lastname: Babbar
mesh_terms: D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D050260:Carbohydrate Metabolism; D002480:Cellulase / Q000378:metabolism; D002957:Citrus / Q000737:chemistry*; D053138:Cyclohexenes / Q000032:analysis; D000431:Ethanol / Q000138:chemical synthesis*; D005285:Fermentation; D005947:Glucose / Q000032:analysis; D006603:Hexuronic Acids / Q000032:analysis; D000077222:Limonene; D015233:Models, Statistical; D011096:Polygalacturonase / Q000378:metabolism; D015203:Reproducibility of Results; D013729:Terpenes / Q000032:analysis; D014866:Waste Products / Q000032:analysis*
chemical_list: D053138:Cyclohexenes; D006603:Hexuronic Acids; D013729:Terpenes; D014866:Waste Products; D000431:Ethanol; C007819:galacturonic acid; D000077222:Limonene; D011096:Polygalacturonase; D002480:Cellulase; D005947:Glucose