Evaluation of Different Methods for the Determination of Maximum Heterotrophic Growth Rates
Abstract:This work evaluated the most commonly used methods for determining maximum heterotrophic specific growth rates (μ m ) in batch reactors. Parallel batch experiments were conducted under various initial substrate-to-biomass (S 0/X 0) ratios and values of the solids retention time (c). The maximum specific growth rate, μ m , was determined simultaneously according to measurements of oxygen consumption (i.e., oxygen uptake rate, OUR) and volatile suspended solids (VSS) increase. The S 0/X 0 ratio was found to significantly influence μ m values. Under high S 0/X 0 ratios (= 20), fast-growing bacteria seemed to gain a competitive advantage resulting in higher μ m values than those obtained under low S 0/X 0 ratios (= 1.5). The OUR-based estimate of μ m (μ m (OUR)), under certain circumstances, is differentiated from μ m that is based on exponential bacterial growth (μ m(VSS)), and seems to be more a measure of substrate oxidation than a measure of bacterial growth. At high S 0/X 0 ratio and low c, μ m(OUR) was significantly higher than the μ m(VSS), indicating that considerable uncoupling between anabolism and catabolism was occurring under these conditions. Batch experiments conducted at high S 0/X 0 ratios seemed to be a more sensitive method for determining μ m values in the presence of an inhibitor than tests conducted at low S 0/X 0 ratios.
Document Type: Research Article
Publication date: 2003-11-01
More about this publication?
- Water Environment Research (WER) is published monthly, including an annual Literature Review. A subscription to WER includes access to the latest content back to 1992, as well as access to fast track articles. An individual subscription is valid for 12 months from month of purchase.
Water Environment Research (WER) publishes peer-reviewed research papers, research notes, state-of-the-art and critical reviews on original, fundamental and applied research in all scientific and technical areas related to water quality, pollution control, and management. An annual Literature Review provides a review of published books and articles on water quality topics from the previous year. Published as: Sewage Works Journal, 1928 - 1949; Sewage and Industrial Wastes, 1950 - 1959; Journal Water Pollution Control Federation, 1959 - Oct 1989; Research Journal Water Pollution Control Federation, Nov 1989 - 1991; Water Environment Research, 1992 - present.
- Editorial Board
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Membership Information
- Information for Advertisers
- WEF Bookstore
- Ingenta Connect is not responsible for the content or availability of external websites