title: UV photolysis for relieved inhibition of sulfadiazine (SD) to biomass growth.
abstract: UV photolysis was used to relieve inhibition of biomass growth by sulfadiazine (SD), a broad-spectrum anti-microbial. To investigate the effects of SD on biomass growth, three substrates-glucose alone (G), glucose plus sulfadiazine (G+SD), and glucose plus photolyzed SD (G+PSD)-were used to culture the bacteria acclimated to glucose. The biomass was strongly inhibited when SD was added into the glucose solution, but inhibition was relieved to a significant degree when the SD was treated with UV irradiation as a pretreatment. The biomass growth kinetics were described well by the Monod model when glucose was used as a substrate alone, but the kinetics followed a hybrid Aiba model for non-competitive inhibition when SD was added to the solution. When photolyzed SD was added to glucose solution to replace original SD, the growth still followed Aiba inhibition, but inhibition was significantly relieved: the maximum specific growth rate (μ max) increased by 17 %, and the Aiba inhibition concentration increased by 60 %. Aniline, a major product of UV photolysis, supported the growth of the glucose-biodegrading bacteria. Thus, UV photolysis of SD significantly relieved inhibition by lowering the SD concentration and by generating a biodegradable product.
authors.affiliation: Department of Environmental Science and Engineering, School of Life and Environmental Science, Shanghai Normal University, Shanghai, 200234, China.
authors.forename: Shihui
authors.initials: S
authors.lastname: Pan
authors.forename: Ning
authors.initials: N
authors.lastname: Yan
authors.forename: Yongming
authors.initials: Y
authors.lastname: Zhang
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Rittmann
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry; D000890:Anti-Infective Agents / Q000737:chemistry; D001419:Bacteria / Q000254:growth & development; D001673:Biodegradation, Environmental; D018533:Biomass; D005947:Glucose / Q000737:chemistry; D007700:Kinetics; D010782:Photolysis; D012722:Sewage; D013411:Sulfadiazine / Q000737:chemistry*; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000737:chemistry; D018508:Water Purification
chemical_list: D000814:Aniline Compounds; D000890:Anti-Infective Agents; D012722:Sewage; D014874:Water Pollutants, Chemical; D013411:Sulfadiazine; D005947:Glucose; C023650:aniline