Fast biodegradation of long-alkanes by enhancing bacteria performance rate by per-oxidation

Jinlan Xu; Yanjie Sun; Guiyong Tian; Xiumin Li; Zhengli Yang

doi:10.1016/j.jenvman.2021.113933

Fast biodegradation of long-alkanes by enhancing bacteria performance rate by per-oxidation

J Environ Manage. 2022 Jan 1:301:113933. doi: 10.1016/j.jenvman.2021.113933. Epub 2021 Oct 14.

Authors

Jinlan Xu¹, Yanjie Sun², Guiyong Tian², Xiumin Li², Zhengli Yang²

Affiliations

¹ School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, 710055, Shaanxi, Xi'an, China; Key Laboratory of Northwest Water Resources, Environment and Ecology, MOE, China; Key Laboratory of Environmental Engineering, Shaanxi Province, China. Electronic address: xujinlan@xauat.edu.cn.
² School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, 710055, Shaanxi, Xi'an, China; Key Laboratory of Northwest Water Resources, Environment and Ecology, MOE, China; Key Laboratory of Environmental Engineering, Shaanxi Province, China.

PMID: 34731951
DOI: 10.1016/j.jenvman.2021.113933

Abstract

The long-alkanes biodegradation rate was generally found slow during widely used pre-oxidation combined with biodegradation for oil contamination treatment, resulting in long and unsustainable removal. In this study, different chitosan content was used to produce iron catalysts for pre-oxidation, and nutrients were added for the long-alkanes biodegradation experiment. Mechanism of Fenton pre-oxidation and improvement in the biodegradation rate of long-alkanes were studied by analyzing the change in organic matter and bacterial community structure, the amount and activity of bacteria in the biological stage, and the degradation amount long-alkanes hydrocarbon before and after pre-oxidation. Results showed that the destruction of bacteria greatly reduced when hydroxyl radical intensity decreased to 4.40 a.u.. Also, the proportion of humic acid-like was high (40.88%), and the community structure was slightly changed with the pre-oxidation for the fast biodegradation (FB) group. In the subsequent biodegradation, it was found that the degradation rate of each long-alkanes in the FB group increased significantly (C₃₀: 4.18-8.32 mg/(kg·d)) with the increase of the degradation of long-alkanes (10-50%). Further studies showed that the high nutrient dynamics (6.05 mg/(kg·d)) of the FB group resulted in high bacteria performance rate (0.53 mol CO₂ × log CFU/(10⁴ g² d)), which further accelerated the substrate transformation(41%). Therefore, the biodegradation rate of long-alkanes was increased (43.8 mg/(kg·d)) with the removal rate of long-alkanes of 76%. The half-life of long-alkanes for the FB group (64 d) was 33 d shorter than the slow biodegradation group (99 d). These results exhibited that pre-oxidation regulation can shorten the bioremediation cycle by improving the biodegradation rate of long-alkanes. This research has good engineering application value.

Keywords: Bacteria performance rate; Fast biodegradation; Long-alkanes; Nutrient dynamics; Oil-contaminated soil; Substrate transformation.

MeSH terms

Alkanes*
Bacteria
Biodegradation, Environmental
Hydrocarbons
Petroleum*

Substances

Alkanes
Hydrocarbons
Petroleum