A novel green approach for fabricating visible, light sensitive nano-broccoli-like antimony trisulfide by marine Sb(v)-reducing bacteria: Revealing potential self-purification in coastal zones

Abstract

Antimony trisulfide (Sb 2 S 3) is industrially important for processes ranging from a semiconductor dopant through batteries to a flame retardant. Approaches for fabricating Sb 2 S 3 nanostructures or thin films are by chemical or physicochemical methods, while there have been no report focused on the biological synthesis of nano Sb 2 S 3. In the present study, we fabricated nano-broccoli-like Sb 2 S 3 using Sb(V) reducing bacteria. Thirty four marine and terrestrial strains are capable of fabricating Sb 2 S 3 after 1-5 days of incubation in different selective media. The nano-broccoli-like bio-Sb 2 S 3 was light sensitive between 400-550 nm, acting as a photo-catalyst with the bandgap energy of 1.84 eV. Moreover, kinetic and mechanism studies demonstrated that a k value of ∼0.27 h −1 with an R 2 = 0.99. The bio-Sb 2 S 3 supplemented system exhibited approximately 18.4 times higher photocatalytic activity for degrading methyl orange (MO) to SO 4 2-, CO 2 and H 2 O compared with that of control system, which had a k value of ∼0.015 h −1 (R 2 = 0.99) under visible light. Bacterial community shift analyses showed that the addition of S or Fe species to the media significantly changed the bacterial communities driven by antimony stress. From this work it appears Clostridia, Bacilli and Gammaproteobacteria from marine sediment are potentially ideal candidates for fabricating bio-Sb 2 S 3 due to their excellent electron transfer capability. Based on the above results, we propose a potential visible light bacterially catalyzed self-purification of both heavy metal and persistent organic contamination polluted coastal waters.

Age‐associated variation in the gut microbiota of chinstrap penguins (Pygoscelis antarctica) reveals differences in food metabolism

“…Variations in the gut microbiota compositions of P. antarctica at different ages were assessed by PERMANOVA test and principal coordinate analysis (PCoA) using the "vegan" package in R v4.0.2, based on both unweighted and weighted UniFrac distances (Lozupone et al, 2011). Weighted Unifrac distance considers not only the species composition but also their relative abundance (Zhao et al, 2017), while unweighted Unifrac distance only considers the composition of the species, without their relative abundance (Zhang et al, 2020). Barplots based on the "ggplot2" package in R v4.0.2 software were used to visualize the relative abundances of dominant bacteria phyla and genera.…”