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Algae and mercury (Hg) are ubiquitous in marine environments. In this study, we investigated the effects of a typical marine algae of diatom Skeletonema costatum on Hg methylation by an iron-reducing bacterium of Geobacter sulfurreducens (G. sulfurreducens) PCA. In the absence of Skeletonema costatum, the bacterial MeHg production rate maximized at 104.06 ± 11.7 ng L -1 h -1 with a high Hg level, while the highest methylation efficiency was achieved at a low Hg concentration. The existence of Skeletonema costatum greatly inhibited the capability of G. sulfurreducens PCA to methylate Hg. With the increase in algal biomass, there was a significant mitigation of MeHg formation and Hg 0 release, leaving a considerable proportion of immobilized Hg 2+ species (up to 47%) associated with algal cell materials. These results suggest that marine algae are crucial in determining the bioavailability of Hg contaminants and the methylating potential of G. sulfurreducens PCA., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Academics researchers and "citizen scientists" from 22 countries confirmed that yellow mealworms, the larvae of Tenebrio molitor Linnaeus, can survive by eating polystyrene (PS) foam. More detailed assessments of this capability for mealworms were carried out by12 sources: five from the USA, six from China, and one from Northern Ireland. All of these mealworms digested PS foam. PS mass decreased and depolymerization was observed, with appearance of lower molecular weight residuals and functional groups indicative of oxidative transformations in extracts from the frass (insect excrement). An addition of gentamycin (30 mg g -1 ), a bactericidal antibiotic, inhibited depolymerization, implicating the gut microbiome in the biodegradation process. Microbial community analyses demonstrated significant taxonomic shifts for mealworms fed diets of PS plus bran and PS alone. The results indicate that mealworms from diverse locations eat and metabolize PS and support the hypothesis that this capacity is independent of the geographic origin of the mealworms, and is likely ubiquitous to members of this species., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The cathodic reduction of complex-state copper(II) was investigated in a dual chamber microbial fuel cell (MFC). The inner resistance of MFC system could be reduced in the presence of ionizing NH(4)(+), however, mass transfer was hindered at higher ammonia concentration. Thermodynamic and electrochemical analyses indicated that the processes of complex dissociation and copper reduction were governed by the ratio of T[Cu]:T[NH(3)] and the pH of solution. The reduction of Cu(NH(3))(4)(2+) could be achieved via two possible pathways: (1) releasing Cu(2+) from Cu(NH(3))(4)(2+), then reducing Cu(2+) to Cu or Cu(2)O and (2) Cu(NH(3))(4)(2+) accepting an electron and forming Cu(NH(3))(2)(+), and depositing as Cu or Cu(2)O consequently. At initial concentration of 350 mg T[Cu] L(-1), copper removal efficiency of 96% was obtained at pH=9.0 within 12 h (with △Cu/△COD=1.24), 84% was obtained at pH=3.0 within 8 h (with △Cu/△COD=1.72). Cu(NH(3))(4)(2+) was reduced as polyhedral deposits on the cathode., (Copyright © 2012 Elsevier Ltd. All rights reserved.)