Copper oxide nanoparticle-resistant ciliate Paramecium jenningsi can detoxify industrial wastewater

Pollution of aquatic systems with industrial effluents that include metal nanoparticles, including copper oxide nanoparticles (CuO NPs), poses a high risk to the environment and human health. These nanoparticles are usually present in industrial wastewater such as pharmaceutical, plastics, and printing. The aim of the study was to consider the potential of the ciliate, Paramecium jenningsi, as a bioremediation agent, which would be able to withstand the toxic impact of CuO NPs. The lowest concentration of inhibition was found to be 1 µL in P. jenningsi. Optimal pH was 7.1 to 7.4 and ideal temperature range was 25°C to 30°C. P. jenningsi showed an impressive response to resistance when exposed to CuO NPs gaining glucose content by 353.8% and glycogen content by 31.54%. Moreover, enzyme activities also increased significantly, where the invertase activity increased by 62.3%, and amylase by 379.93%. These results show that besides being resistant, P. jenningsi has a detoxifying effect on CuO NPs, as well, and supports its use as a bioindicator and bioremediation of metal nanoparticles-contaminated industrial effluents. This study is a promising solution to the reduction of the pollution in water bodies as ciliates can help in improving the sustainability of the environment.