title: Pretreatment of rice straw by proton beam irradiation for efficient enzyme digestibility.
abstract: Biomass was pretreated with proton beam irradiation (PBI) in order to enhance enzyme digestibility. Rice straw and soaking in aqueous ammonia (SAA)-treated rice straw were treated with 1-25 kGy doses of PBI at a beam energy of 45 MeV. The optimal doses of PBI for efficient sugar recovery were 15 and 3 kGy for rice straw and SAA-treated rice straw, respectively. When PBI was applied to rice straw at 15 kGy, the glucose conversion reached 68% of the theoretical maximum at 72 h. When 3 kGy of PBI was applied to SAA-treated rice straw, approximately 90% of the theoretical glucose conversion was obtained at 12 h compared to a 89% conversion at 48 h. After 2 h of enzymatic saccharification, the initial reaction rates of raw rice straw pretreated with 15 kGy of PBI and SAA-treated rice straw pretreated with 3 kGy of PBI were 1.4 × 10⁻⁴ and 9.7 × 10⁻⁴ g L⁻¹ s⁻¹, respectively. Further, the results of X-ray diffractometry support the effect of PBI on sugar recovery, whereas scanning electron microscopy images revealed a more rugged rice straw surface.
authors.affiliation: Department of Chemical and Biological Engineering, Korea University, 1 Anam-dong, Sungbuk-ku, Seoul 136-701, Korea.
authors.forename: Sung Bong
authors.initials: SB
authors.lastname: Kim
authors.forename: Jun Seok
authors.initials: JS
authors.lastname: Kim
authors.forename: Jong Ho
authors.initials: JH
authors.lastname: Lee
authors.forename: Seong Woo
authors.initials: SW
authors.lastname: Kang
authors.forename: Chulhwan
authors.initials: C
authors.lastname: Park
authors.forename: Seung Wook
authors.initials: SW
authors.lastname: Kim
mesh_terms: D000641:Ammonia / Q000737:chemistry; D056804:Biofuels; D018533:Biomass; D001709:Biotechnology / Q000379:methods*; D044602:Cellulases / Q000378:metabolism*; D004307:Dose-Response Relationship, Radiation; D005285:Fermentation; D005656:Fungal Proteins / Q000378:metabolism*; D005947:Glucose / Q000096:biosynthesis*; D006868:Hydrolysis; D012275:Oryza / Q000378:metabolism*; D011522:Protons
chemical_list: D056804:Biofuels; D005656:Fungal Proteins; D011522:Protons; D000641:Ammonia; D044602:Cellulases; D005947:Glucose