Complex sentence: MFCs that do not use a membrane can deploy anaerobic bacteria in aerobic environments however, membrane-less MFCs will experience cathode contamination by the indigenous bacteria and the power-supplying microbe.
Split into simpler sentences: MFCs that do not use a membrane can deploy anaerobic bacteria in aerobic environments. However, membrane-less MFCs experience cathode contamination by the indigenous bacteria and the power-supplying microbe.