Although a number of pioneering works have been reported on treatment of arsenic containing wastewater by various techniques, only a few studies on a microbial route for detoxification of arsenic has been reported so far.
For instance, there have been reports on decreased microbial diversity in general [2], [3], and depletion of beneficial bacteria such as bifidobacteria in particular [4], although these trends have not been universally reported [5], [6].
Many of the identified constituents of pyrolysis oil, however, have previously been reported to display adverse effects on microbial growth.
Beside of nCeO2, other engineered metal oxides-NPs such as nAg NPs (Das et al. 2012), nZnO NPS (Meli et al. 2016) and TiO2 NPs (Shah et al. 2014) have also been reported to have toxic effects on microbial community from several ecosystem.
The impact of nCeO2 NP on microbial community has also been reported by Antisari et al. (2013) who revealed that though microbial biomass was not statistically affected by nCeO2 NPs, the microbial stress or changes was noted.
Vancomycin has been reported to induce consistent changes on intestinal microbial structures of humans treated with that drug [ 32], but another study reported unpredictable changes caused by the same drug [ 33].
Microbial keratitis has been reported previously following this procedure [ 2- 5].
Extensive studies on microbial phytases especially from genus Aspergillus have been reported involving isolation, properties, fermentation, cloning, expression, structure, and so forth [ 6, 9, 26].
NPs have been reported to show an inhibitory effect on those metabolites suggesting a potential negative impact of NPs on intercellular interactions in microbial communities [59, 60].
Previous studies have shown an inconclusive effect of microbial diversity on bioreactor purification performance, as high performance has been reported in biofilters displaying both high (Ding et al. 2008) and low (Steele et al. 2005) microbial diversities.
