Biodegradation of alkylphenols by rhizosphere microorganisms isolated from the roots of Hosta undulata

Abstract

The present study was conducted for the bioremediation of alkylphenols using rhizosphere microorganisms isolated from the roots of land plant. Three land plants (Hosta undulata, Anemone flaccida, and Aquilegia flabellate var. pumila) were used to analyze the tolerance against petroleum hydrocarbons and alkylphenols. The plant Hosta undulata showed the tolerance against petroleum hydrocarbons (500 mg kg−1) and one of the alkylphenol, i.e., 4-tert-butylphenol (4-t-BP). Hence, thirty bacterial and thirteen fungal strains were isolated from the 4-t-BP contaminated soil collected from the roots of this plant. Biodegradation of alkylphenols was investigated using the isolated bacteria and fungi. Decrement in the alkylphenols concentration was analyzed using high pressure liquid chromatography (HPLC). Fungi showed higher 4-t-BP degradation than bacteria. Strain SB-4 (Penicillium pinophilum) showed 76.8 %, and strain SB-7 (Trichoderma asperellum) showed 49.2 % degradation of 4-t-BP. Apart from 4-t-BP, strain SB-7 degraded other alkylphenols such as 4-sec-butylphenol, 4-tert-octylphenol, and 4-nonylphenol. The major metabolites produced during alkylphenols degradation with strain SB-7 were determined using Gas chromatography linked with mass spectrometry (GC–MS). The results showed that the plant Hosta undulata had tolerance against the toxic compounds, and the rhizosphere microorganisms isolated from the roots of this plant might be applied for the bioremediation of alkylphenols contaminated soils.