A metabolic-activity-detecting approach to life detection: Restoring a chemostat from stop-feeding using a rapid bioactivity assay

作者：Li Shiue Lin; Bai Ming Der; Hsiao Chia Jung; Cheng Sheng Shung; Nealson Kenneth H

来源：Bioelectrochemistry, 2017, 118: 147-153.

DOI：10.1016/j.bioelechem.2017.08.001

• Amperometric measurement
• Bioactivity assay
• Clostridium sp.
• Hexacyanoferrate
• Life detection
• Polyviologen

A mediated glassy carbon electrode covered by a thin-film polyviologen was used in the present study to rapidly detect bioactivity in a mixed-culture chemostat (dominated by Clostridium sp.). With the addition of 1 mM hexacyanoferrate and 9 mM glucose, the current increasing rate (dl/dt) measured under a poised potential of 500 mV (vs. Ag/AgCI) can be defined as the quantity of metabolic activity. In the experiment of restoring the chemostat from stop-feeding, it is suggested that when the dI/dt was >2 mu A min(-1), the influent pump could be directly turned on to maintain the high dilution rate of 0.5 h(-1); when the dI/dt was lower than 2 A min(-1), reducing the dilution rate would be needed to avoid cell wash out. Since the soluble mediators and polyviologen film will enhance performances by favorable electron transfer and positively charged surfaces, respectively, we suggest that the method can also be employed to detect the bioactivities in environmental samples.

• 出版日期2017-12