Batch-mode stimulation of hydrocarbons biodegradation in freshwater sediments from historically contaminated Alūksne lake

Kristine Kalneniece; Dita Gudra; Ludvigs Lielauss; Turs Selga; Davids Fridmanis; Janis Terauds; Olga Muter

doi:10.1016/j.jconhyd.2022.104103

Batch-mode stimulation of hydrocarbons biodegradation in freshwater sediments from historically contaminated Alūksne lake

J Contam Hydrol. 2023 Feb:253:104103. doi: 10.1016/j.jconhyd.2022.104103. Epub 2022 Nov 17.

Authors

Kristine Kalneniece¹, Dita Gudra², Ludvigs Lielauss³, Turs Selga⁴, Davids Fridmanis², Janis Terauds³, Olga Muter⁵

Affiliations

¹ Department of Microbiology & Biotechnology, Faculty of Biology, University of Latvia, 1 Jelgavas Str., Riga LV-1004, Latvia.
² Latvian Biomedical Research and Study Center, 1 Ratsupites Str., Riga LV-1067, Latvia.
³ Baltijas Juras Geologijas Centrs Ltd., 67A Ieriku Str., LV-1084 Riga, Latvia.
⁴ Faculty of Medicine, University of Latvia, 1 Jelgavas Str., Riga LV-1004, Latvia.
⁵ Department of Microbiology & Biotechnology, Faculty of Biology, University of Latvia, 1 Jelgavas Str., Riga LV-1004, Latvia. Electronic address: olga.mutere@lu.lv.

PMID: 36435695
DOI: 10.1016/j.jconhyd.2022.104103

Abstract

Historical contamination of freshwater lakes with hydrocarbons (HC) due to anthropogenic activities represents a serious problem worldwide. This study was focused on hydrocarbons-contaminated sediments sampled in Lake Alūksne of glacial origin in Northeast Latvia. The batch experiments were aimed at evaluating the effect of bio-stimulation and bioaugmentation on the biodegradation of hydrocarbons in lake sediments (LS), as well as changes in microbial community structure and metabolic activity. The sediments were sampled from two points of the lake, 4-5 m and 8 m depth, respectively. These samples slightly differed by colour, count of diatoms, microbial respiration intensity and colour intensity of 2,6- dichlorophenolindophenol. Nevertheless, the trend in biodegradation activity was similar for both LS samples. The concentration of HC in LS during the 32-day incubation decreased in average from 465 mg/kg to 165 mg/kg and 117.5 mg/kg in the LS amended with nutrients and nutrients+microbial community, respectively. Different treatment types of LS resulted in differences in microbial respiration and HC-degrading activity. The Shotgun sequencing has revealed the main phyla present in the intact LS being Proteobacteria (48.8%), Actinobacteria (24.4%), Firmicutes (10.4%) and Bacteroidetes (5.0%). Incubation of LS for 32 days resulted in increasing abundance of Proteobacteria from 48.8% in the raw LS to 58-62%, mainly due to the increase of Betaproteobacteria. The functional annotation of gene families revealed that the most abundant gene families were associated with ATP binding, metal ion, magnesium ion, sulfur cluster, zinc ion binding, DNA binding and other essential components for cell functioning. The Shannon biodiversity index of culturable microorganisms in EcoPlates™ ranged from 2.28 to 2.85. The data obtained in this study indicated that the suggested approach is a potent remediation technology for further ex situ scaling up.

Keywords: Bioremediation; Functional gene families; Hydrocarbons; Respiration intensity; Shotgun sequencing.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bacteria / metabolism
Biodegradation, Environmental
Biodiversity
Geologic Sediments
Hydrocarbons
Lakes* / microbiology
Microbiota*

Substances

Hydrocarbons