The engineering and microbiological aspects involved in the production of alginate-like exopolysaccharides (ALE) and tryptophan (TRY) in aerobic granular sludge systems were evaluated. The inclusion of short anoxic phase (A/O/A cycle–anaerobic, oxic, and anoxic phase) and the control of sludge retention time (SRT ≈ 10 days) proved to be an important strategy to increase the content of these bioproducts in granules. The substrate concentration also has a relevant impact on the production of ALE and TRY. The results of the microbiological analysis showed that slow-growing heterotrophic microbial groups (i.e., PAOs and GAOs) might be associated with the production of ALE, and the EPS-producing fermentative bacteria might be associated with the TRY production. The preliminary economic evaluation indicated the potential of ALE recovery in AGS systems in decreasing the OPEX (operational expenditure) of the treatment, especially for larger sewage treatment plants or industrial wastewaters with a high organic load.

评估了在好氧颗粒污泥系统中生产藻酸盐样胞外多糖 (ALE) 和色氨酸 (TRY) 所涉及的工程和微生物学方面。包含短缺氧阶段（A/O/A 循环-厌氧、好氧和缺氧阶段）和控制污泥停留时间（SRT ≈ 10 天）被证明是增加颗粒中这些生物产品含量的重要策略. 底物浓度也对 ALE 和 TRY 的产生有相关影响。微生物学分析结果表明，生长缓慢的异养微生物群（即PAOs和GAOs）可能与ALE的产生有关，产EPS发酵菌可能与TRY的产生有关。