title: A novel steam explosion sterilization improving solid-state fermentation performance.
abstract: Traditional sterilization of solid medium (SM) requires lengthy time, degrades nutrients, and even sterilizes inadequately compared with that of liquid medium due to its low thermal conductivity. A novel sterilization strategy, high-temperature and short-time steam explosion (SE), was exploited for SM sterilization in this study. Results showed that SE conditions for complete sterilization were 172 °C for 2 min and 128 °C for 5 min. Glucose and xylose contents in medium after SE sterilization increased by 157% and 93% respectively compared with those after conventional sterilization (121 °C, 20 min) while fermentation inhibitors were not detected. FTIR spectra revealed that the mild SE conditions helped to release monosaccharides from the polysaccharides. Bacillus subtilis fermentation productivity on medium after SE sterilization was 3.83 times of that after conventional sterilization. Therefore, SE shortened sterilization time and improved SM nutrition, which facilitated fermentability of SM and should promote economy of solid-state fermentation.
authors.affiliation: State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Zhi-Min
authors.initials: ZM
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China. Electronic address: wanglan@ipe.ac.cn.
authors.forename: Lan
authors.initials: L
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, PR China.
authors.forename: Hong-Zhang
authors.initials: HZ
authors.lastname: Chen
mesh_terms: D001407:Bacillus / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology*; D049109:Cell Proliferation / Q000502:physiology; D002470:Cell Survival / Q000502:physiology; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005285:Fermentation / Q000502:physiology; D005947:Glucose / Q000737:chemistry* / Q000378:metabolism*; D013227:Steam; D013242:Sterilization / Q000295:instrumentation*; D014994:Xylose
chemical_list: D013227:Steam; D014994:Xylose; D005947:Glucose
keywords: Image processing; Nutrition; Solid medium; Steam explosion; Sterilization