title: Denitrification performance and microbial diversity in a packed-bed bioreactor using biodegradable polymer as carbon source and biofilm support.
abstract: A novel kind of biodegradable polymer, i.e., starch/polycaprolactone (SPCL) was prepared and used as carbon source and biofilm support for biological denitrification in a packed-bed bioreactor. The denitrification performances and microbial diversity of biofilm under different operating conditions were investigated. The results showed that the average denitrification rate was 0.64 ± 0.06 kg N/(m(3)d), and NH3-N formation (below 1mg/L) was observed during denitrification. The nitrate removal efficiency at 15°C was only 55.06% of that at 25°C. An initial excess release of DOC could be caused by rapid biodegradation of starch in the surfaces of SPCL granules, then it decreased to 10.08 mg/L. The vast majority of species on SPCL biofilm sample (99.71%) belonged to six major phyla: Proteobacteria, Bacteroidetes, Chloroflexi, Firmicutes, Spirochaetes and Actinobacteria. Proteobacteria were the most abundant phylum (85.50%) and mainly consisted of β-proteobacteria (82.39%). Diaphorobacter and Acidovorax constituted 52.75% of the identified genera which were denitrifying bacteria.
authors.affiliation: Chinese Research Academy of Environmental Sciences, Beijing 100012, PR China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Shen
authors.forename: Yuexi
authors.initials: Y
authors.lastname: Zhou
authors.forename: Jun
authors.initials: J
authors.lastname: Hu
authors.forename: Jianlong
authors.initials: J
authors.lastname: Wang
mesh_terms: D001673:Biodegradation, Environmental; D044822:Biodiversity; D018441:Biofilms; D019149:Bioreactors; D002244:Carbon / Q000737:chemistry*; D004269:DNA, Bacterial / Q000235:genetics; D058440:Denitrification; D004867:Equipment Design; D006863:Hydrogen-Ion Concentration; D009566:Nitrates / Q000737:chemistry; D011091:Polyesters / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D020560:Proteobacteria / Q000378:metabolism; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D013213:Starch / Q000737:chemistry; D013696:Temperature
chemical_list: D004269:DNA, Bacterial; D009566:Nitrates; D011091:Polyesters; D011108:Polymers; D012336:RNA, Ribosomal, 16S; C016240:polycaprolactone; D002244:Carbon; D013213:Starch