Enhanced reduction of an azo dye using henna plant biomass as a solid-phase electron donor, carbon source, and redox mediator.
The multiple effects of henna plant biomass as a source of carbon, electron donor, and redox mediator (RM) on the enhanced bio-reduction of Orange II (AO7) were investigated. The results indicated that the maximum AO7 reduction rate in the culture with henna powder was ∼6-fold that in the sludge control culture lacking henna. On the one hand, AO7 reduction can be advantageously enhanced by the release of available electron donors; on the other hand, the associated lawsone can act as a fixed RM and play a potential role in shuttling electrons from the released electron donors to the final electron acceptor, AO7. The soluble chemical oxygen demand (SCOD) during each experiment and the FTIR spectra suggested that the weakened AO7 reduction along with the retention of henna powder might not be attributed to the lack of fixed lawsone but rather to the insufficiency of electron donors.
Institute of Environmental Science and Engineering, Hangzhou Dianzi University, Hangzhou 310018, PR China. Electronic address: hjg@hdu.edu.cn.
Jingang
J
Huang
Institute of Environmental Science and Engineering, Hangzhou Dianzi University, Hangzhou 310018, PR China.
Shushan
S
Chu
Institute of Environmental Science and Engineering, Hangzhou Dianzi University, Hangzhou 310018, PR China.
Jianjun
J
Chen
Department of Applied Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, 16521 Prague 6, Czech Republic.
Yi
Y
Chen
Institute of Environmental Science and Engineering, Hangzhou Dianzi University, Hangzhou 310018, PR China.
Zhengmiao
Z
Xie
D001391:Azo Compounds / Q000737:chemistry*; D001557:Benzenesulfonates / Q000737:chemistry*; D018533:Biomass; D031564:Lawsonia Plant / Q000737:chemistry*; D010084:Oxidation-Reduction; D013425:Sulfanilic Acids / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D001391:Azo Compounds; D001557:Benzenesulfonates; D013425:Sulfanilic Acids; D014874:Water Pollutants, Chemical; C014722:2-naphthol orange
Electron donor; Henna plant biomass; Lawsone; Orange II; Redox mediator