Microbial fouling induced by typical extreme environment-resistant bacteria in oligotrophic solutions of simulated condensate of manned spacecrafts

Microbial fouling is an important challenge in water recovery system of manned spacecrafts for longer term missions. Microbial fouling of 5A06 aluminium alloy induced by typical extreme environment-resistant bacteria in oligotrophic solutions of simulated condensate of manned spacecraft was investigated. Bacillus cereus showed poor survival ability to oligotrophic environments, and a small amount of remaining live B. cereus cells mainly existed in the form of spores without forming biofilms. And when B. cereus was mixed cultured with Cupriavidus metallidurans, the system was mainly affected by C. metallidurans biofilms rather than B. cereus cells. C. metallidurans could promote the thickness of passive films of aluminum alloy, so C. metallidurans posed a minor threat to the corrosion of 5A06 aluminum alloy. However, C. metallidurans showed strong adaptability to oligotrophic environments and formed a large number of biofilms. And the contamination threat of C. metallidurans still dominated even cultured with B. cereus. Even when cultured with B. cereus, the threat of contamination from C. metallidurans still pre-dominates. Therefore, C. metallidurans would pose a threat of microbial fouling to the oligotrophic water recovery system of manned spacecrafts.