title: Effect of mild alkali pretreatment on structural changes of reed (Phragmites communis Trinius) straw.
abstract: The effect of dilute sodium hydroxide (NaOH) on reed straw structural change at 105 degreeC temperature was evaluated in this study. Various concentrations of NaOH (1% to 2.5%) were used for pretreatment of reed straw at 105 degreeC for 10min. Scanning electron microscopy, atomic force microscopy and Fourier transform infrared spectroscopy studies showed that 2% and 2.5% NaOH pretreated sample exposed more cellulose fibers compared with other treatments. The cellulose crystalline index was increased by the 1% to 2.0% NaOH treatments and slightly lowered by the 2.5% NaOH treatment due to destructing cellulose fibres. Two per cent NaOH pretreatment caused 69.9% lignin removal, whereas 2.5% NaOH pretreatment removed 72.4% lignin. Besides, reed straw, when pretreated at 2% and 2.5% NaOH, resulted 56.4% and 60.5% hemicellulose removal, respectively. However, the difference in removal of lignin and hemicellulose between 2% and 2.5% NaOH treated reed straw was very marginal. In addition, very negligible increase of cellulose level was estimated, amounting 78.8% and 76.6% in 2.5% and 2% NaOH-treated sample, respectively. Moreover, after 72 h, reducing sugar yield was 81.2% and 83.3% using enzyme loading of 15 FPU (g dry biomass)-' and 30 IU (g dry biomass)- and xylanase 4 FXU (g dry biomass)-1 from 2% and 2.5% NaOH pretreated reed straw, respectively. Reducing sugar yield was increased very marginally when NaOH concentration increased from 2% to 2.5% for reed straw pretreatment. Therefore, 2% NaOH is supposed to be effective for reed straw pretreatment at this mentioned condition.
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Chinju, Republic of Korea.
authors.forename: Dhirendra Nath
authors.initials: DN
authors.lastname: Barmana
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Chinju, Republic of Korea.
authors.forename: Md Azizul
authors.initials: MA
authors.lastname: Haquea
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Chinju, Republic of Korea.
authors.forename: Tae Ho
authors.initials: TH
authors.lastname: Kang
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Chinju, Republic of Korea.
authors.forename: Gi Hwan
authors.initials: GH
authors.lastname: Kim
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Chinju, Republic of Korea.
authors.forename: Tae Yang
authors.initials: TY
authors.lastname: Kim
authors.affiliation: Gyeongsangnam-do Agricultural Research and Extension Service, Chinju, Republic of Korea.
authors.forename: Min Keun
authors.initials: MK
authors.lastname: Kim
authors.affiliation: Division of Applied Life Science (BK21 Program), Gyeongsang National University, Chinju, Republic of Korea.
authors.forename: Han Dae
authors.initials: HD
authors.lastname: Yun
mesh_terms: D000468:Alkalies / Q000737:chemistry; D002482:Cellulose / Q000737:chemistry* / Q000648:ultrastructure*; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D035261:Plant Components, Aerial / Q000737:chemistry* / Q000648:ultrastructure*; D006109:Poaceae / Q000737:chemistry* / Q000648:ultrastructure*; D012972:Sodium Hydroxide / Q000737:chemistry*
chemical_list: D000468:Alkalies; D012972:Sodium Hydroxide; D002482:Cellulose