Next Article in Journal
Occupational Exposure to Solar Radiation at Different Latitudes and Pterygium: A Systematic Review of the Last 10 Years of Scientific Literature
Next Article in Special Issue
Biocapture of CO2 by Different Microalgal-Based Technologies for Biogas Upgrading and Simultaneous Biogas Slurry Purification under Various Light Intensities and Photoperiods
Previous Article in Journal
A Survey of Naturally-Occurring Steroid Hormones in Raw Milk and the Associated Health Risks in Tangshan City, Hebei Province, China
Previous Article in Special Issue
Spatiotemporal Variations and Driving Factors of Air Pollution in China
Article Menu
Issue 1 (January) cover image

Export Article

Open AccessArticle

Aerobic Biodegradation Characteristic of Different Water-Soluble Azo Dyes

State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210046, China
Author to whom correspondence should be addressed.
Int. J. Environ. Res. Public Health 2018, 15(1), 35;
Received: 10 November 2017 / Revised: 17 December 2017 / Accepted: 20 December 2017 / Published: 26 December 2017
(This article belongs to the Special Issue Remediation and Analysis of Soil, Air, and Water Pollution)
PDF [1611 KB, uploaded 26 December 2017]


This study investigated the biodegradation performance and characteristics of Sudan I and Acid Orange 7 (AO7) to improve the biological dye removal efficiency in wastewater and optimize the treatment process. The dyes with different water-solubility and similar molecular structure were biologically treated under aerobic condition in parallel continuous-flow mixed stirred reactors. The biophase analysis using microscopic examination suggested that the removal process of the two azo dyes is different. Removal of Sudan I was through biosorption, since it easily assembled and adsorbed on the surface of zoogloea due to its insolubility, while AO7 was biodegraded incompletely and bioconverted, the AO7 molecule was decomposed to benzene series and inorganic ions, since it could reach the interior area of zoogloea due to the low oxidation-reduction potential conditions and corresponding anaerobic microorganisms. The transformation of NH3-N, SO42− together with the presence of tryptophan-like components confirm that AO7 can be decomposed to non-toxic products in an aerobic bioreactor. This study provides a theoretical basis for the use of biosorption or biodegradation mechanisms for the treatment of different azo dyes in wastewater. View Full-Text
Keywords: azo dye; aerobic biodegradation; Acid Orange 7; Sudan I; solubility azo dye; aerobic biodegradation; Acid Orange 7; Sudan I; solubility

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).

Supplementary material


Share & Cite This Article

MDPI and ACS Style

Sheng, S.; Liu, B.; Hou, X.; Wu, B.; Yao, F.; Ding, X.; Huang, L. Aerobic Biodegradation Characteristic of Different Water-Soluble Azo Dyes. Int. J. Environ. Res. Public Health 2018, 15, 35.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Int. J. Environ. Res. Public Health EISSN 1660-4601 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top