Enhanced Biodegradation of HMW- PAHs using Immobilized Microorganisms in an Estuarine Reed Wetlands Simulator

Abstract

Abstract. Biodegradation of pyrene and indeno(1,2,3-cd)pyrene in reed rhizosphere soil was carried out in a small-scale wetland simulator using reed as well as microorganisms immobilized on cinder beads under natural environmental conditions. The results show that the stability of the introduced strains was enhanced upon immobilization and that the depletion of pyrene and indeno(1,2,3-cd)pyrene after 40 days was 68.4%, and 87.9%, respectively, whereas reeds or immobilized cells alone exhibited relatively poor degradation of PAHs in the same time period. This showed that plant and microbes promoted the degradation of pyrene and indeno(1,2,3-cd)pyrene. The results of this study show that PAH-degrading bacteria associated with plants could enhance pollutant removal, and this offers opportunities to facilitate high molecular weight (HMW) PAHs plant-microbe remediation in wetlands.

Enhanced degradation of indeno(1,2,3-cd)pyrene using Candida tropicalis NN4 in presence of iron nanoparticles and produced biosurfactant: a statistical approach

“…after 25 days of incubation. Moreover, Huang et al (2015) showed 87.9% InP degradation using immobilized bacterial cells in the soil after 40 days of incubation. Therefore, in the present study, the presence of Fe nanoparticles and produced biosurfactant in the medium showed a remarkable increase in the InP degradation (61 ± 0.04-79 ± 0.05%) using C. tropicalis NN4 only after 15 days of incubation.…”

“…El-Sheshtawy and Ahmed (2017) reported crude oil degradation using Bacillus licheniformis in presence of produced biosurfactant in the medium and specific concentration of (Fe 2 O 3 and Zn 5 OH 8 C l2 ) nanoparticles. So far Huang et al (2015) reported 87.9% of indeno(1,2,3-cd) pyrene degradation in reed rhizosphere soil using microorganisms immobilized on cinder beads under natural environmental condition after 40 days of incubation; whereas, the present study had shown 90.68% of indeno(1,2,3-cd)pyrene degradation using C. tropicalis NN4 after 15 days of incubation in an aqueous medium in presence of Fe nanoparticles and produced biosurfactant under optimized conditions which shows the novelty of the present work.…”

“…86 Page 2 of 13 has been proposed as one of the effective means to remediate PAHs from contaminated environments. A large number of PAHs degrading bacteria have been isolated, but reports are scanty in case of microorganisms as degrader of indeno(1,2,3-cd)pyrene (Huang et al 2015;Du et al 2010). Though yeasts are tolerant to changes in adverse environmental conditions (Ooi et al 2003), reports are less on yeast as biodegrader of high molecular weight PAHs like InP (Bhattacharya et al 2014).…”

“…A large number of PAHs degrading microorganisms have been isolated, but reports are scanty in case of microorganisms as degrader of indeno(1,2,3-cd)pyrene (Huang et al 2015;Du et al 2010).…”