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Xylitol production from corncob hemicellulose is a popular process in China. Microbial conversion of xylose to xylitol, as a biological process with many advantages, has drawn increasing attention. As a by-product from the manufacturing of xylitol, corncob cellulosic residues are produced in very large amounts and represent an environmental problem. As a result, considering the large amount of xylitol production in China, the conversion of corncob cellulosic residues has become a widespread issue having to be tackled. After the hemicellulose in corncob has been hydrolyzed for xylitol production, the corncob cellulosic residue is porous and can easily be hydrolyzed by cellulases into glucose and further converted to ethanol, another high-added-value chemical. Based on the latest technology advancements in xylitol, cellulase, and ethanol production, the integrated production of ethanol from corncob cellulosic residues appears as a promising way to improve the profit of the whole xylitol production process. [ABSTRACT FROM AUTHOR]

Background and aims: Avicennia marina is a pioneer mangrove species widely distributed along the southeast coast of China. It suffers, especially in the seedling stage, from the tidal flooding and anaerobic surroundings as it closes to the seaward side. The aim of this study is to assess the ability of A. marina seedlings to withstand different tidal inundations by physiological and proteomic approaches. Methods: To accomplish this, the artificial tidal inundations were mimicked as 0, 4, and 8 h per tidal cycle about 1 week. The physiological approaches and two-dimensional electrophoresis coupled with MALDI-TOF/TOF-MS technology were used to reveal the adaptive alterations of A. marina seedlings to tidal inundation. Results: There were profound changes in photosynthesis and chlorophyll fluorescence characteristics of A. marina seedling leaves under inundation treatment. Particularly, photosynthetic rate increased at 4 h inundation, while decreasing at 8 h inundation treatment compared with control (0 h). The results highlighted that A. marina seedlings could greatly upregulate the abundances of photosynthesis-related proteins, activate antioxidant and defense systems to efficiently suppress the reactive oxygen species (ROS) burst and cell damages, mobilize carbohydrate metabolism associated proteins, and then maintain cellular homeostasis, resulting in well adaptation to short-term tidal inundation. Conclusion: Overall, our results demonstrated that short-term inundation is beneficial, while long-term inundation is detrimental to A. marina. The results allow us to recognize the roles of specific proteins in molecular tolerance to tidal inundation in mangrove plants. [ABSTRACT FROM AUTHOR]

Production of chitinase from bacteria has distinct advantages over fungi, due to the formation of mycelia of fungi in the later phase of fermentation. A novel chitinase-producing bacterial strain XJ-01 was isolated from the Yulu fishing field of Changsha, Hunan province, China, by enrichment and spread-plate technique, sequentially. Physicochemical characterization and 16S rRNA sequencing revealed that strain XJ-01 belongs to Serratia marcescens. By optimizing the fermentation condition based on L(3) orthogonal experimental design, a maximal chitinase activity up to 15.36 U/ml was attained by that stain under the condition: 0.5% (NH)SO as the nitrogen source, 0.75% colloidal chitin as the carbon source, temperature of 32°C, time of 32 h and pH 8.0. [ABSTRACT FROM AUTHOR]