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To improve biohydrogen production, the performance of dark fermentation by cocultures and the immobilization system with activated carbon (AC) were investigated. Results of batch tests illustrated that lower yield was obtained by monoculture Enterobacter cancerogeous HG6 2A (A) and Enterobacter homaechei 83 (B). The defects of monocultures could be overcome by cocultures in dark fermentation. The optimum A:B number ratio of 0.9:1 was recommended. The optimum loading rate of AC was 200 g/L in the immobilization system, corresponding to the biohydrogen yield of 1.203 mol/mol-glucose. The biohydrogen production of the immobilization system increased 259% in comparison to that of the suspension cell system, indicating that immobilization was an effective method of improving biohydrogen production. The surface attachment and the synergistic effect explained the higher performance of the cell immobilization system.

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A simple fluorescence and electrochemical dualchannel biosensor based on bifunctional Zr(IV)-based metal− organic framework (Zr-MOF) was proposed to detect Ochratoxin A (OTA). The bifunctional Zr-MOF, with photoluminescence properties and enormous electroactive ligands, was exploited to load OTA-specific aptamers for designing signal probes, greatly simplifying the probe-fabrication process and improving sensing reliability. Upon specific recognition of aptamer toward OTA, the anchored probe was released from the sensing interface into the reaction solution. In this circumstance, the increased amount of the signal probe in reaction solution led to an enhanced fluorescence response, while the decreased amount of the signal probe on the sensing interface resulted in a diminished electrochemical response. According to the dual-channel signal change with increasing OTA concentration, the visual fluorescence strategy was established for intuitive OTA detection, and meanwhile, sensitive electrochemical assay with a detection limit of 0.024 pg/mL was also achieved with the help of one-step electrodeposition as a sensing platform. Moreover, the proposed dual-channel assay has been successfully applied to determine OTA levels in corn samples with rapid response, superior accuracy, and high antiinterference capability, providing a promising method for food safety monitoring.