title: Fermentation of rice hull by Aspergillus japonicus under ultrasonic pretreatment.
abstract: The application of ultrasound for treating rice hull used as the fermentation substrate for xylooligosaccharides production was investigated. Aspergillus japonicus CY6-1 was selected to produce cellulolytic and xylanolytic enzymes from untreated rice hull (RH) and rice hull treated with ultrasound (USRH-M). The hemicellulose yield was increased to 1.4-fold with ultrasound, and treatment time was greatly shortened from 24h to 1.5h at 80 °C and 300 W/28 kHz. The morphology of RH from various pretreatments was observed with field emission scanning electron microscope (FESEM), revealing the surface structure of USRH-M smoother than that of RH. USRH-M was much easier to be utilized by fungi, to extend the stability of enzyme activity and to increase activities of CMCase, β-glucosidase, and xylanase compared with those of untreated RH. The final fermentative products were xylotetraose, xylohexaose, and higher molecular weight xylooligosaccharides, achieving xylohexaose yield for USRH-M 80% higher than that for RH group.
authors.affiliation: Department of Food Science and Biotechnology, National Chung Hsing University, 250 Kuokuang Road, Taichung 40227, Taiwan, ROC.
authors.forename: Chun-Yao
authors.initials: CY
authors.lastname: Yang
authors.forename: I-Chuan
authors.initials: IC
authors.lastname: Sheih
authors.forename: Tony J
authors.initials: TJ
authors.lastname: Fang
mesh_terms: D001230:Aspergillus / Q000378:metabolism* / Q000528:radiation effects* / Q000648:ultrastructure*; D005965:Glucuronates / Q000096:biosynthesis*; D019220:High-Energy Shock Waves; D009844:Oligosaccharides / Q000096:biosynthesis*; D012275:Oryza / Q000382:microbiology* / Q000528:radiation effects*; D035261:Plant Components, Aerial / Q000382:microbiology / Q000528:radiation effects; D011829:Radiation Dosage; D013010:Sonication / Q000379:methods*
chemical_list: D005965:Glucuronates; D009844:Oligosaccharides; C570991:xylooligosaccharide