title: Inoculation and alkali coeffect in volatile fatty acids production and microbial community shift in the anaerobic fermentation of waste activated sludge.
abstract: Batch fermentations of waste activated sludge (WAS) at alkaline pH with different inocula were performed. Paper mill anaerobic granular sludge (PAS) and dyeing mill anaerobic sludge (DAS) were used as inocula. At pH 10 the inoculation did not increase the volatile fatty acids (VFAs) production compared to the non-inoculated samples fermented in the same conditions, and the maximal VFAs yield of non-inoculated WAS was higher than inoculated WAS. However, at pH 9 the inoculation with PAS increased the sludge hydrolysis and VFAs production was 1.7-fold higher than that in non-inoculated WAS (yield 52.40mg/g of volatile solid). Denaturing gradient gel electrophoresis analysis revealed that 3 bacterial species, identified as Proteocatella, Tepidibacter, and Clostridium, disappeared when inoculated with PAS at pH 9 or at pH⩾10. The results showed that the inoculation with PAS can be helpful to achieve a relatively high VFAs production from WAS in a moderate alkaline environment.
authors.affiliation: School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006, PR China.
authors.forename: Long
authors.initials: L
authors.lastname: Huang
authors.affiliation: School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006, PR China.
authors.forename: Ben
authors.initials: B
authors.lastname: Chen
authors.affiliation: School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006, PR China.
authors.forename: Marco
authors.initials: M
authors.lastname: Pistolozzi
authors.affiliation: School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006, PR China. Electronic address: btzhqwu@scut.edu.cn.
authors.forename: Zhenqiang
authors.initials: Z
authors.lastname: Wu
authors.affiliation: School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006, PR China.
authors.forename: Jufang
authors.initials: J
authors.lastname: Wang
mesh_terms: D000468:Alkalies / Q000494:pharmacology*; D000693:Anaerobiosis / Q000187:drug effects; D001419:Bacteria / Q000187:drug effects / Q000378:metabolism*; D056804:Biofuels; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology; D058645:Denaturing Gradient Gel Electrophoresis; D005232:Fatty Acids, Volatile / Q000096:biosynthesis*; D005285:Fermentation / Q000187:drug effects*; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D006868:Hydrolysis / Q000187:drug effects; D064307:Microbiota / Q000187:drug effects*; D010802:Phylogeny; D011134:Polysaccharides / Q000032:analysis; D011506:Proteins / Q000032:analysis; D012722:Sewage / Q000382:microbiology*; D012995:Solubility; D014835:Volatilization / Q000187:drug effects; D062065:Wastewater / Q000382:microbiology*
chemical_list: D000468:Alkalies; D056804:Biofuels; D005232:Fatty Acids, Volatile; D011134:Polysaccharides; D011506:Proteins; D012722:Sewage; D062065:Wastewater
keywords: Alkaline; Inoculum; Microbial community; Volatile fatty acid; Waste activated sludge