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Tiamulin (TIA) is a widely used antibiotic in Thai swine farms and persists in swine manure storage. Significant amounts remain in swine manure after composting, posing risks related to the spread of the compound and the evolution of resistant genes when this compost is used as a fertilizer. Therefore, it is necessary to enhance TIA degradation. This study successfully purified TIA-degrading fungi, which have a high capacity for treating antibiotic-contaminated manure. Twelve strains were collected from swine farms and preliminarily examined for their ability to degrade recalcitrant compounds using brilliant green and crystal violet dyes at 0.05% (w/v). Three isolated fungi and three white-rot fungal strains–namely, Lasiodiplodia sp. F1, Fusarium sp. F5, Galactomyces sp. F8, Verticillium sp., Trametes versicolor , and Trametes hirsuta AK4–capable of developing considerable decolorized zones on both dyes exhibited their abilities to degrade 10 mg l −1 of TIA over a period of 12 days: 93.2 ± 0.0%, 82.4 ± 10.2%, 73.8 ± 5.6%, 89.3 ± 0.0%, 86.1 ± 0.0%, and 66.8 ± 4.8%, respectively. Lasiodiplodia sp. F1, Verticillium sp., and Trametes versicolor were able to remove TIA most efficiently (>85%) and have the potential to be applied to swine waste for the elimination of antibiotic substances. Manganese peroxidase (MnP) was predominantly produced; MnP expression was induced by tiamulin, suggesting its main role in TIA degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ulva rigida and Gracilaria fisheri improve gut health in vitro differently. • Seaweed polysaccharides are not digestible by small intestinal enzymes. • Seaweeds and polysaccharides stimulate beneficial microbes and SCFAs output in vitro. • The red seaweed Gracilaria fisheri has more potential as a source of prebiotics. This study explored the gut health potential of the green seaweed Ulva rigida (SW-U) and the red seaweed Gracilaria fisheri (SW-G), as well as polysaccharide-enriched extracts (PF-U and PF-G, respectively). The polysaccharide-enriched extracts were not digestible by small intestinal enzymes, but the morphology of samples was changed. After 24 h in vitro fermentation, seaweeds and polysaccharide-enriched extracts significantly increased (p < 0.05) production of total short-chain fatty acids (SCFAs) (29.4–35.4 µmoL/mL) compared to the control (17.9 µmoL/mL). The G. fisheri showed more potential for improving gut health than U. rigida. Particularly, PF-G induced butyric acid production comparable to that of inulin control (5.4 and 6.9 µmoL/mL) and the highest production when compared with other substrates (1.8–3.3 µmoL/mL). While SW-G stimulated the growth of beneficial bacteria, including Roseburia and Faecalibacterium. These findings further demonstrate that seaweeds and their derived polysaccharides have the potential to be used as dietary supplements with gut health benefits. [ABSTRACT FROM AUTHOR]

Abstract: Microbial regrowth introduces several problems to the use of reclaimed water, such as health concerns, aesthetic deterioration, and biofouling. This study evaluated assimilable organic carbon (AOC), which is a part of the biodegradable organic matter promoting microbial growth, in water reclamation systems in Japan. The AOC concentration in the reclaimed water from various treatment processes ranged between 36 and 446 μg C/L (median 316 μg C/L). The AOC concentration in the reclaimed water from the plants equipped with ozonation was significantly higher – more than two times – than that in the reclaimed water from plants equipped with other processes. UV and chlorine also changed the AOC concentration slightly. Moreover, reverse osmosis produced reclaimed water with the lowest AOC content. Processes equipped with membrane filtration were effective in removing seed microorganisms that enter the distribution system. Microbial growth in reclaimed water distribution systems occurred when the total and free residual chlorine was lower than 0.36 and 0.09 mg/L, respectively. The AOC reduction occurred simultaneously with regrowth, which suggests that AOC could support microbial growth in reclaimed-water-distribution systems. As the residual chlorine is often depleted during distribution and storage, it is essential to control the AOC to suppress microbial growth. [Copyright &y& Elsevier]

Abstract: Inefficient removal of estrone (E1) in wastewater treatment plants (WWTPs) causes feminizing effects in male aquatic creatures. As E1 is mainly removed by biodegradation, investigation of E1 degradation is important to determine better removal strategies. Using microautoradiography-fluorescence in situ hybridization (MAR-FISH), we demonstrated that the structures of [3H]E1-incorporating bacterial communities were different at different E1 concentrations applied to activated sludge. At 200 μg/L E1, almost all [3H]E1-incorporating cells were associated with either Betaproteobacteria or Gammaproteobacteria (60% and 40% of MAR (+) cells, respectively). The proportion of Betaproteobacteria and Gammaproteobacteria in the total number of [3H]E1-incorporating cells decreased as the concentration of E1 decreased. In contrast, the proportion of Alphaproteobacteria in the total number of [3H]E1-incorporating cells increased as the concentrations of E1 decreased. At the lowest applied concentration (540 ng/L), almost all the [3H]E1-incorporating cells were Alphaproteobacteria (96%). The results of MAR-FISH applied to sludge samples collected from various plant locations and activated sludge processes, and during different seasons also demonstrated the high contribution of Alphaproteobacteria to the entire E1-degrading bacterial community (50.4 ± 11% of the total number of [3H]E1-incorporating cells) at 1 μg/L E1. Since the E1 concentration in domestic wastewater is at sub-μg/L levels, the key E1 degraders in activated sludge of domestic WWTPs are probably be Alphaproteobacteria. All [3H]E1-incorporating Alphaproteobacteria were hybridized with probe ALF968. Few MAR (+) cells were Sphingomonadales. An E1-degrading bacterial community at low E1 concentration appeared to consist of diverse bacterial groups of Alphaproteobacteria. This study suggested that substrate concentration is an essential factor for revealing E1-degrading bacteria in complex communities. [Copyright &y& Elsevier]

• Acclimatization increased 2-MBT removal efficiency of bacterial consortia. • The most efficient consortium degraded up to 300 mg L−1 2-MBT in medium. • It had higher efficiency than the previously reported bacterial strains. • The dominant populations were Pseudomonas and Stenotrophomonas. • When applied to rubber wastewater, it removed 79 % 2-MBT and 93 % COD. Benzothiazoles especially 2-mercaptobenzothiazole (2-MBT) in rubber industrial wastewater can be released into the environment. They can cause adverse health impacts. This study aimed to obtain efficient 2-MBT-degrading bacteria for wastewater application. The bacterial consortia were enriched by incubating rubber wastewater sludge in a medium containing 2-MBT for 28 days. Stepwise acclimatization was conducted with increasing 2-MBT concentrations from 50 to 200 mg L−1 in nitrogen-containing medium for 76 days. The process significantly increased the bacterial number and changed the dominant populations. Among these consortia, the EN consortium from benzothiazole-containing sludge had the highest specific 2-MBT biodegradation rate of 5.2 ± 0.5 mg L−1 day−1 mg protein-1 and could degrade up to 300 mg L−1 2-MBT. From 16S rRNA gene analysis, Pseudomonas was the dominant genus at approximately 70 % of the total population. S tenotrophomonas was the second most abundant populations and have never been reported for 2-MBT biodegradation. The EN consortium removed 65–79 % and 90–93 % of 112 mg L−1 2-MBT and ∼4000 mg L−1 COD in rubber wastewater, respectively, which were significantly higher than the values of natural attenuation. Therefore, the EN consortium could be an ideal inoculum for the post-treatment of benzothiazoles in rubber industrial wastewater. [ABSTRACT FROM AUTHOR]

Peri-urban aquacultures produce nutritious food in proximity to markets, but poor surface water quality in rapidly expanding megacities threatens their success in emerging economies. Our study compared, for a wide range of parameters, water quality downstream of Bangkok with aquaculture regulations and standards. For parameters not meeting those requirements, we sought to establish whether aquaculture practice or external factors were responsible. We applied conventional and advanced methods, including micropollutant analysis, genetic markers, and 16S rRNA amplicon sequencing, to investigate three family-owned aquacultures spanning extensive, semi-intensive and intensive practices. Canals draining the city of Bangkok did not meet quality standards for water to be used in aquaculture, and were sources for faecal coliforms, Bacteriodes , Prevotella , Human E. coli , tetracycline resistance genes, and nitrogen into the aquaculture ponds. Because of these inputs, aquacultures suffered algae blooms, with and without fertilizer and feed addition to the ponds. The aquacultures were sources of salinity and the herbicide diuron into the canals. Diuron was detectable in shrimp, but not at a level of concern to human health. Given the extent and nature of pollution, peri-urban water policy should prioritize charging for urban wastewater treatment over water fees for small-scale agricultural users. The extensive aquaculture attenuated per year an estimated twenty population equivalents of nitrogen pollution and trillions of faecal coliform bacteria inputs from the canal. Extensive aquacultures could thus contribute to peri-urban blue-green infrastructures providing ecosystem services to the urban population such as flood risk management, food production and water pollution attenuation. Unlabelled Image • Extensive, semi-intensive and intensive aquacultures near Bangkok were investigated. • Aquaculture water quality was severely affected by urban pollution in the canals. • Aquacultures released herbicides/algaecides into canals. • Extensive aquacultures attenuated faecal pollution inputs from the canals. • Extensive aquaculture could be integrated in blue-green infrastructures. [ABSTRACT FROM AUTHOR]