Aims: The aim of this study is to evaluate the utility of aerobically grown microbial granules for the biological treatment of phenol‐containing wastewater. Methods and Results: A column‐type sequential aerobic sludge blanket reactor was inoculated with activated sludge and fed with phenol as the sole carbon source, at a rate of 1·5 g phenol l −1  d −1 . Aerobically grown microbial granules first appeared on day 9 of reactor operation and quickly grew to displace the seed flocs as the dominant form of biomass in the reactor. These granules were compact and regular in appearance, and consisted of bacterial rods and cocci and fungi embedded in an extracellular polymeric matrix. The granules had a mean size of 0·52 mm, a sludge volume index of 40 ml g −1 and a specific oxygen utilization rate of 110 mg oxygen g VSS −1  h −1 (VSS stands for volatile suspended solids). Specific phenol degradation rates increased with phenol concentration from 0 to 500 mg phenol l −1 , peaked at 1·4 g phenol g VSS −1  d −1 , and declined with further increases in phenol concentration as substrate inhibition effects became important. Conclusions: Aerobically grown microbial granules were successfully cultivated in a reactor maintained at a loading rate of 1·5 g phenol l −1  d −1 . The granules exhibited a high tolerance towards phenol. Significant rates of phenol degradation were attained at phenol concentrations as high as 2 g l −1 . Significance and Impact of the Study: This is the first study to demonstrate the ability of aerobically grown microbial granules to degrade phenol. These granules appear to represent an excellent immobilization strategy for microorganisms to biologically remove phenol and other toxic chemicals in high‐strength industrial wastewaters.

Nanostructured ZnO with its unique properties could provide a suitable microenvironment for immobilization of enzymes while retaining their biological activity, and thus lead to an expanded use of this nanomaterial for the construction of electrochemical biosensors with enhanced analytical performance. ZnO-based enzyme electrochemical biosensors are summarized in several tables for an easy overview according to the target biosensing analyte (glucose, hydrogen peroxide, phenol and cholesterol), respectively. Moreover, recent developments in enzyme electrochemical biosensors based on ZnO nanomaterials are reviewed with an emphasis on the fabrications and features of ZnO, approaches for biosensor construction (e.g., modified electrodes and enzyme immobilization) and biosensor performances.

Bacteria play key roles in the function and diversity of aquatic systems, but aside from study of specific bloom systems, little is known about the diversity or biogeography of bacteria associated with harmful cyanobacterial blooms (cyanoHABs). CyanoHAB species are known to shape bacterial community composition and to rely on functions provided by the associated bacteria, leading to the hypothesized cyanoHAB interactome, a coevolved community of synergistic and interacting bacteria species, each necessary for the success of the others. Here, we surveyed the microbiome associated with Microcystis aeruginosa during blooms in 12 lakes spanning four continents as an initial test of the hypothesized Microcystis interactome. We predicted that microbiome composition and functional potential would be similar across blooms globally. Our results, as revealed by 16S rRNA sequence similarity, indicate that M. aeruginosa is cosmopolitan in lakes across a 280 longitudinal and 90 latitudinal gradient. The microbiome communities were represented by a wide range of operational taxonomic units and relative abundances. Highly abundant taxa were more related and shared across most sites and did not vary with geographic distance, thus, like Microcystis, revealing no evidence for dispersal limitation. High phylogenetic relatedness, both within and across lakes, indicates that microbiome bacteria with similar functional potential were associated with all blooms. While Microcystis and the microbiome bacteria shared many genes, whole-community metagenomic analysis revealed a suite of biochemical pathways that could be considered complementary. Our results demonstrate a high degree of similarity across global Microcystis blooms, thereby providing initial support for the hypothesized Microcystis interactome.