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h i g h l i g h t sAzo dye toxicity could shock the bioanode electrochemical activity. Anode biofilm was acclimated to azo dye toxicity by gradient increase of azo dye concentration. Enhanced azo dye removal in single-chamber biocatalyzed electrolysis system after bioanode acclimation. Removing IEM reduced the Rin 3 times than in the presence of IEM by EIS. a r t i c l e i n f o t r a c tAzo dye is widely used in printing and dyeing process as one of refractory wastewaters for its high chroma, stable chemical property and toxicity for aquatic organism. Biocatalyzed electrolysis system (BES) is a new developed technology to degrade organic waste in bioanode and recover recalcitrant contaminants in cathode with effective decoloration. The ion exchange membrane (IEM) separate anode and cathode for biofilm formation protection. Azo removal efficiency was up to 60.8%, but decreased to 20.5% when IEM was removed. However, expensive ion exchange membrane (IEM) not suitable for further practical application, bioelectrochemical activity of bioanode is sensitive to the toxicity of azo dye. A gradient increase of azo dye concentration was used to acclimate anode biofilm to pollutant toxicity. The azo removal efficiency can be enhanced to 73.3% in 10 h reaction period after acclimation. The highest removal efficiency reached 83.7% and removal rates were increased to 8.37 from 3.04 g/h/L of dualchamber. That indicated the feasibility for azo dye removal by single-chamber BES. The IEM cancellation not only decreased the internal resistance, but increased the current density and azo dye removal.

h i g h l i g h t sBiocathode could form in single-chamber BES by absorbing the electrochemical activity microbes from anode biofilm naturally. From abiocathode to biocathode, both the polarization current and charge transfer resistance were improved in 2 weeks. Azo dye removal was accelerated in biocatalyzed electrolysis system with biocathode comparing with abiocathode. a r t i c l e i n f o t r a c tBiocatalyzed electrolysis systems (BES) have been the topic of a great deal of research. However, the biocathodes formed in single-chamber BES without extra inocula have not previously been researched. Along with the formation of biocathodes, the polarization current increased to 1.76 mA from 0.35 mA of abio-cathodes at À1.2 V (vs. SCE). Electrochemical impedance spectroscopy (EIS) results also indicated that the charge transfer resistance (R ct ) was decreased to 148.9 X, less than 1978 X of the abio-cathodes cleared. The performance of the biocathodes was tested for azo dye decolorization, and the dye removal efficiency was 13.3 ± 3.2% higher than abio-cathodes with a 0.5 V direct current (DC) power supply. These aspects demonstrate that biocathode accelerates the rate of electrode reaction in BES and comparing with noble metal catalysts, biocathodes have low toxicity or non-toxic and reproducible properties, which can be widely applied in bioelectrochemical field in the future.

h i g h l i g h t sFeeding with glucose obtained higher AYR decolorization efficiency than acetate. Diverse cathodic bacterial communities were observed with different co-substrates. Glucose-fed condition was dominated with Citrobacter, Enterococcus and Alkaliflexus. Acetate-fed condition was dominated with Acinetobacter and Achromobacter. Co-substrate types impacted performance and the cathodic bacterial communities. a r t i c l e i n f o t r a c tSelective enrichment of cathodic bacterial community was investigated during reductive decolorization of AYR fedding with glucose or acetate as co-substrates in biocathode. A clear distinction of phylotype structures were observed between glucose-fed and acetate-fed biocathodes. In glucose-fed biocathode, Citrobacter (29.2%), Enterococcus (14.7%) and Alkaliflexus (9.2%) were predominant, and while, in acetate-fed biocathode, Acinetobacter (17.8%) and Achromobacter (6.4%) were dominant. Some electroactive or reductive decolorization genera, like Pseudomonas, Delftia and Dechloromonas were commonly enriched. Both of the higher AYR decolorization rate (k AYR = 0.46) and p-phenylenediamine (PPD) generation rate (k PPD = 0.38) were obtained fed with glucose than acetate (k AYR = 0.18; k PPD = 0.16). The electrochemical behavior analysis represented a total resistance in glucose-fed condition was about 73.2% lower than acetate-fed condition. The different co-substrate types, resulted in alteration of structure, richness and composition of bacterial communities, which significantly impacted the performances and electrochemical behaviors during reductive decolorization of azo dyes in biocathode.

Glycosylation has been reported to affect the epitopes of food allergens, however, there are few reports on its role in crab allergen. In the present study, the effect of glycosylation on the IgE-binding activity of tropomyosin (TM), a major allergen in Scylla paramamosain, was investigated. The results showed that TM was a glycoprotein with a 0.2% carbohydrate moiety and contained O-glycan. Moreover, enzymatic deglycosylation of TM by glycosidase had no effect on the IgE-binding activity of TM. In contrast, treatment with periodate resulted in a significant reduction in its IgE-binding activity.

Electrochemical active biofilms (EABs) have attracted considerable attractions in bioelectrochemical systems (BESs) field for pollutants degradation from waste water. However, few studies have looked at EABs formation influenced by anode and cathode conditions. Therefore, EABs feature was investigated under different electrode conditions using a single-chamber BES. After EABs formation, the BES was effective in decolorizing the targeted pollutant azo dye, comparing to abio-electrode BESs. By analyzing the EABs microbial community compositions, anode EAB was dominated by a model electro-active Geobacter (29%), whereas the cathode EAB microbial structure was relatively closer to the inoculum with low abundance Geobacter (2.5%). This study suggested that changing the inoculum composition would be conducive to improving the cathode EAB capability for recalcitrant pollutant degradation in actual engineering applications.