title: Colorimetric measurement of carbohydrates in biological wastewater treatment systems: A critical evaluation.
abstract: Four laboratory preparations and three commercially available assay kits were tested on the same carbohydrate samples with the addition of 14 different interfering solutes typically found in wastewater treatment plants. This work shows that a wide variety of solutes can interfere with these assays. In addition, a comparative study on the use of these assays with different carbohydrate samples was also carried out, and the metachromatic response was clearly influenced by variation in sample composition. The carbohydrate content in the supernatant of a submerged anaerobic membrane bioreactor (SAMBR) was also measured using these assays, and the amount in the different supernatant samples, with and without a standard addition of glucose to the samples, showed substantial differences. We concluded that the carbohydrates present in wastewater measured using these colorimetric methods could be seriously under- or over-estimated. A new analytical method needs to be developed in order to better understand the biological transformations occurring in anaerobic digestion that leads to the production of soluble microbial products (SMPs) and extracellular polymeric substance (EPS).
authors.affiliation: Advanced Environmental Biotechnology Center, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore, 637141, Singapore; Division of Environmental and Water Resources Engineering, School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
authors.forename: Chencheng
authors.initials: C
authors.lastname: Le
authors.affiliation: Advanced Environmental Biotechnology Center, Nanyang Environment & Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, CleanTech One, Singapore, 637141, Singapore; Department of Chemical Engineering, Imperial College London, SW7 2AZ, UK. Electronic address: d.stuckey@imperial.ac.uk.
authors.forename: David C
authors.initials: DC
authors.lastname: Stuckey
mesh_terms: D019149:Bioreactors; D002241:Carbohydrates / Q000032:analysis*; D003124:Colorimetry / Q000379:methods* / Q000592:standards; D005947:Glucose / Q000032:analysis; D007202:Indicators and Reagents / Q000592:standards; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000032:analysis*
chemical_list: D002241:Carbohydrates; D005947:Glucose; D007202:Indicators and Reagents; D062065:Wastewater
keywords: Biological wastewater treatment; Carbohydrate quantitation; Colorimetric carbohydrate assay; Extracellular polymeric substance (EPS); Soluble microbial products (SMPs)