title: The stability of textile azo dyes in soil and their impact on microbial phospholipid fatty acid profiles.
abstract: The aim of this study was to examine the stability of structurally different azo dyes in soil and their impact on the microbial community composition by analyzing phospholipid fatty acid (PLFA) profiles. Sterile and non-sterile soils were amended with three azo dyes, including: Direct Red 81, Reactive Black 5 and Acid Yellow 19 at 160mgkg(-1) soil. The results showed that the azo dyes were quite stable and that large amounts of these dyes ranging from 17.3% to 87.5% were recoverable from the sterile and non-sterile soils after 14 days. The maximum amount of dye was recovered in the case of Direct Red 81. PLFA analysis showed that the azo dyes had a significant effect on microbial community structure. PLFA concentrations representing Gram-negative bacteria in dye-amended soil were substantially less as compared to the PLFA concentration of Gram-positive bacteria. Acid Yellow 19 dye had almost similar effects on the PLFA concentrations representing bacteria and fungi. In contrast, Reactive Black 5 had a greater negative effect on fungal PLFA than that on bacterial PLFA, while the opposite was observed in the case of Direct Red 81. To our knowledge, this is the first study reporting the stability of textile azo dyes in soil and their effects on soil microbial community composition.
authors.affiliation: Department of Environmental Sciences, University of California, Riverside 92507, USA. Electronic address: imran1631@gmail.com.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Imran
authors.affiliation: Department of Soil, Water and Agricultural Engineering College of Agricultural and Marine Sciences, Sultan Qaboos University, 123, Oman.
authors.forename: Baby
authors.initials: B
authors.lastname: Shaharoona
authors.affiliation: Department of Environmental Sciences, University of California, Riverside 92507, USA.
authors.forename: David E
authors.initials: DE
authors.lastname: Crowley
authors.affiliation: Department of Environmental Sciences, PMAS Arid Agriculture University, Rawalpindi 46300, Pakistan.
authors.forename: Azeem
authors.initials: A
authors.lastname: Khalid
authors.affiliation: Department of Environmental Sciences & Engineering, Government College University, Faisalabad 38040, Pakistan.
authors.forename: Sabir
authors.initials: S
authors.lastname: Hussain
authors.affiliation: Institute of Soil & Environmental Sciences, University of Agriculture, Faisalabad 38040, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Arshad
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D001419:Bacteria / Q000737:chemistry / Q000187:drug effects; D005227:Fatty Acids / Q000737:chemistry*; D005658:Fungi / Q000737:chemistry / Q000187:drug effects; D010743:Phospholipids / Q000737:chemistry*; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000737:chemistry*; D013784:Textiles
chemical_list: D001391:Azo Compounds; D005227:Fatty Acids; D010743:Phospholipids; D012987:Soil; D012989:Soil Pollutants
keywords: Azo dyes; Microbial community structure; PLFA; Soil contamination; Textile wastewater