TY - JOUR

T1 - Impacts of n-alkane concentration on soil bacterial community structure and alkane monooxygenase genes abundance during bioremediation processes

AU - Liu, Y.

AU - Ding, A.

AU - Sun, Y.

AU - Xia, X.

AU - Zhang, Dayi

PY - 2018/10

Y1 - 2018/10

N2 - Petroleum hydrocarbons, mainly consisting of n-alkanes and polycyclic aromatic hydrocarbons (PAHs), are considered as priority pollutants and biohazards in the environment, eventually affecting the ecosystem and human health. Though many previous studies have investigated the change of bacterial community and alkane degraders during the degradation of petroleum hydrocarbons, there is still lack of understanding on the impacts of soil alkane contamination level. In the present study, microcosms with different n-alkane contamination (1%, 3% and 5%) were set up and our results indicated a complete alkane degradation after 30 and 50 days in 1%- and 3%-alkane treatments, respectively. In all the treatments, alkanes with medium-chain length (C11-C14) were preferentially degraded by soil microbes, followed by C27-alkane in 3% and 5% treatments. Alkane contamination level slightly altered soil bacterial community, and the main change was the presence and abundance of dominant alkane degraders. Thermogemmatisporaceae, Gemmataceae and Thermodesulfovibrionaceae were highly related to the degradation of C14- and C27-alkanes in 5% treatment, but linked to alkanes with medium-chain (C11-C18) in 1% treatment and C21-alkane in 3% treatment, respectively. Additionally, we compared the abundance of three alkane-monooxygenase genes, e.g., alk_A, alk_P and alk_R. The abundance of alk_R gene was highest in soils, and alk_P gene was more correlated with alkane degradation efficiency, especially in 5% treatment. Our results suggested that alkane contamination level showed non-negligible effects on soil bacterial communities to some extents, and particularly shaped alkane degraders and degrading genes significantly. This study provides a better understanding on the response of alkane degraders and bacterial communities to soil alkane concentrations, which affects their biodegradation process. [Figure not available: see fulltext.]. © 2018, Higher Education Press and Springer-Verlag GmbH Germany, part of Springer Nature.

AB - Petroleum hydrocarbons, mainly consisting of n-alkanes and polycyclic aromatic hydrocarbons (PAHs), are considered as priority pollutants and biohazards in the environment, eventually affecting the ecosystem and human health. Though many previous studies have investigated the change of bacterial community and alkane degraders during the degradation of petroleum hydrocarbons, there is still lack of understanding on the impacts of soil alkane contamination level. In the present study, microcosms with different n-alkane contamination (1%, 3% and 5%) were set up and our results indicated a complete alkane degradation after 30 and 50 days in 1%- and 3%-alkane treatments, respectively. In all the treatments, alkanes with medium-chain length (C11-C14) were preferentially degraded by soil microbes, followed by C27-alkane in 3% and 5% treatments. Alkane contamination level slightly altered soil bacterial community, and the main change was the presence and abundance of dominant alkane degraders. Thermogemmatisporaceae, Gemmataceae and Thermodesulfovibrionaceae were highly related to the degradation of C14- and C27-alkanes in 5% treatment, but linked to alkanes with medium-chain (C11-C18) in 1% treatment and C21-alkane in 3% treatment, respectively. Additionally, we compared the abundance of three alkane-monooxygenase genes, e.g., alk_A, alk_P and alk_R. The abundance of alk_R gene was highest in soils, and alk_P gene was more correlated with alkane degradation efficiency, especially in 5% treatment. Our results suggested that alkane contamination level showed non-negligible effects on soil bacterial communities to some extents, and particularly shaped alkane degraders and degrading genes significantly. This study provides a better understanding on the response of alkane degraders and bacterial communities to soil alkane concentrations, which affects their biodegradation process. [Figure not available: see fulltext.]. © 2018, Higher Education Press and Springer-Verlag GmbH Germany, part of Springer Nature.

KW - Alkane degraders

KW - Alkane-monooxygenase genes

KW - n-alkane biodegradation

KW - n-alkane contamination level

KW - Petroleum hydrocarbon contaminated site

KW - Soil bacterial community

KW - Bacteria

KW - Biodegradation

KW - Bioremediation

KW - Chains

KW - Contamination

KW - Degradation

KW - Gasoline

KW - Genes

KW - Polycyclic aromatic hydrocarbons

KW - Soil pollution

KW - Soils

KW - Contaminated sites

KW - Contamination levels

KW - Monooxygenases

KW - n-Alkanes

KW - Paraffins

U2 - 10.1007/s11783-018-1064-5

DO - 10.1007/s11783-018-1064-5

M3 - Journal article

VL - 12

JO - Frontiers of Environmental Science and Engineering

JF - Frontiers of Environmental Science and Engineering

SN - 2095-2201

IS - 5

M1 - 3

ER -