Phyto-mycoremediation of benzo[a]pyrene in soil by combining the role of yeast consortium and sunflower plant

Abstract

Aim: The present work aims to demonstrate the influence of plant-microbe interaction towards removal of benzo[a]pyrene (BaP) in a microcosm through a phyto-mycoremediation approach using sunflower plant (Helianthus annuus) and yeast consortium. o Methodology: Sunflower plants were planted in pots containing BaP spiked soil. The rhizosphere of sunflower plant was amended with yeast consortium, YC01 consisting of Rhodotorula sp. NS01, Hanseniaspora opuntiae NS02 and Debaryomyces hansenii NS03 by root inoculation. The soil containing BaP (50 mg kg-1) were exposed to various treatments, monitored for a period of 45 d and residual BaP concentration was checked by GC-MS analysis. Results: The removal of BaP was noted in the order of treatments as follows: rice husk immobilised phyto/myco remediation (93%) > phyto/ mycoremediation (82%) > phytoremediation (76%) > mycoremediation (69%). The BaP removal rates from soil for the above treatments were expressed in terms of half-life period recorded as 11.31 d, 17.07 d, 21.66 d and 25.38 d, respectively. Dehydrogenase activity was increased greatly with time for the immobilised phyto-mycoremediation. Interpretation: Bio-stimulation of soil with yeast consortium immobilized on rice husk enhanced the total activity of yeasts in the soil. Combined treatment using yeast consortium immobilized on rice husk and sunflower plant showed faster and maximum BaP degradation. Therefore it Online C can be concluded that the use of sunflower plant along with yeast consortium as a dual approach can serve as an effective tool for remediation of BaP contaminated soil.