1
|
Neilen AD, Carroll AR, Hawker DW, O'Brien KR, Burford MA. Identification of compounds from terrestrial dissolved organic matter toxic to cyanobacteria. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 749:141482. [PMID: 32827821 DOI: 10.1016/j.scitotenv.2020.141482] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/30/2020] [Accepted: 08/03/2020] [Indexed: 06/11/2023]
Abstract
There is emerging evidence for the phytotoxicity of terrestrial dissolved organic matter (DOM), however its sources, transformations and ecological effects in aquatic ecosystems are poorly understood. DOM characterization by Nuclear Magnetic Resonance (NMR) spectroscopy has typically involved solid-state techniques, but poor resolution has often precluded identification of individual components. This study is the first to directly identify individual phytotoxic components using a novel combined approach of preparative HPLC fractionation of DOM (obtained from leaves of two common riparian trees, Casuarina cunninghamiana and Eucalyptus tereticornis). This was followed by chemical characterization of fractions, using one-dimensional (1D) and two-dimensional (2D) solution-state 1H NMR analyses. Additionally, the phytotoxic effect of the fractions was determined using cultures of the cyanobacteria Raphidiopsis (Cylindrospermopsis) raciborskii. The amino acid, proline, from Casuarina leachate was identified as phytotoxic, while for Eucalyptus leachate, it was gallic acid and polyphenols. These phytotoxicants remained in the leachates when they were incubated in sunlight or the dark conditions over 5 days. Our study identifies phytotoxic compounds with the potential to affect algal species composition, and potentially control nuisance R. raciborskii blooms.
Collapse
Affiliation(s)
- Amanda D Neilen
- Australian Rivers Institute, Griffith University, Nathan, QLD 4111, Australia; Griffith School of Environment and Science, Griffith University, Nathan, QLD 4111, Australia.
| | - Anthony R Carroll
- Griffith School of Environment and Science, Griffith University, Nathan, QLD 4111, Australia; Environmental Futures Research Institute, Griffith University, Gold Coast, QLD 4111, Australia.
| | - Darryl W Hawker
- Griffith School of Environment and Science, Griffith University, Nathan, QLD 4111, Australia.
| | - Katherine R O'Brien
- School of Chemical Engineering, Faculty of Engineering, Architecture and Information Technology, University of Queensland, St Lucia, QLD 4072, Australia.
| | - Michele A Burford
- Australian Rivers Institute, Griffith University, Nathan, QLD 4111, Australia; Griffith School of Environment and Science, Griffith University, Nathan, QLD 4111, Australia.
| |
Collapse
|
2
|
Neilen AD, Carroll AR, Hawker DW, O'Brien KR, Burford MA. Effects of photochemical and microbiological changes in terrestrial dissolved organic matter on its chemical characteristics and phytotoxicity towards cyanobacteria. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 695:133901. [PMID: 31756858 DOI: 10.1016/j.scitotenv.2019.133901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 08/08/2019] [Accepted: 08/12/2019] [Indexed: 06/10/2023]
Abstract
Previous studies have shown that under laboratory conditions, dissolved organic matter (DOM) leached from plants can be differentially more phytotoxic to cyanobacteria, compared to green algae. This study examined how DOM source and transformation processes (microbial and photochemical) affect its chemical composition and phytotoxicity towards a cultured species of cyanobacteria (Raphidiopsis raciborskii) using a factorial experimental design. To complement cyanobacterial bioassays, the chemical composition and associated changes in DOM were determined using spectroscopic (nuclear magnetic resonance (NMR) and absorbance) and elemental analyses. Sunlight exposed DOM from leaves of the terrestrial plants, Casuarina cunninghamiana and Eucalyptus tereticornis had the most phytotoxic effect compared to DOM not exposed to sunlight. This phytotoxic DOM was characterised by relatively low nitrogen content, containing highly coloured and relatively high molecular mass constituents. Both mixed effect model and PCA approaches to predict inhibition of photosynthetic yield indicated phytotoxicity could be predicted (P < 0.001) based upon the following parameters: C: N ratio; gilvin, and lignin-derived phenol content of DOM. Parallel proton-detected 1D and 2D NMR techniques showed that glucose anomers were the major constituents of fresh leachate. With ageing, glucose anomers disappeared and products of microbial transformation appeared, but there was no indication of the appearance of additional phytotoxic compounds. This suggests that reactive oxygen species may be responsible, at least partially, for DOM phytotoxicity. This study provides important new information highlighting the characteristics of DOM that link with phytotoxic effects.
Collapse
Affiliation(s)
- Amanda D Neilen
- Australian Rivers Institute & Griffith School of Environment and Science, Griffith University, Nathan, QLD 4111, Australia.
| | - Anthony R Carroll
- Griffith School of Environment, Environmental Futures Research Institute, Griffith University, Gold Coast Campus, Parklands Drive, Southport, Queensland 4222, Australia.
| | - Darryl W Hawker
- Griffith School of Environment and Science, Griffith University, Nathan, QLD 4111, Australia.
| | - Katherine R O'Brien
- School of Chemical Engineering, Faculty of Engineering, Architecture and Information Technology, University of Queensland, St Lucia, QLD 4072, Australia.
| | - Michele A Burford
- Australian Rivers Institute & Griffith School of Environment and Science, Griffith University, Nathan, QLD 4111, Australia.
| |
Collapse
|
3
|
Gilbert M, Bährs H, Steinberg CEW, Wilhelm C. The artificial humic substance HS1500 does not inhibit photosynthesis of the green alga Desmodesmus armatus in vivo but interacts with the photosynthetic apparatus of isolated spinach thylakoids in vitro. PHOTOSYNTHESIS RESEARCH 2018; 137:403-420. [PMID: 29777430 DOI: 10.1007/s11120-018-0513-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 05/01/2018] [Indexed: 06/08/2023]
Abstract
Humic substances (HSs) can influence the growth and composition of freshwater phytoplankton assemblage. Since HSs contain many phenolic and quinonic moieties and cause growth reductions in eco-physiological field experiments, HSs are considered photosystem II herbicides. To test this specific mode of action in vivo and in vitro, respectively, we used intact cells of the green alga Desmodesmus armatus, as well as thylakoids isolated from spinach (Spinacia oleracea) as a model system for the green algal chloroplast. Photosynthetic electron transport was measured as oxygen evolution and variable chlorophyll fluorescence. The in vivo effect of the artificial humic substance HS1500 on algae consisted of no impact on photosynthesis-irradiance curves of intact green algae compared to untreated controls. In contrast, addition of HS1500 to isolated thylakoids resulted in light-induced oxygen consumption (Mehler reaction) as an in vitro effect. Fluorescence induction kinetics of HS-treated thylakoids revealed a large static quenching effect of HS1500, but no inhibitory effect on electron transport. For the case of intact algal cells, we conclude that the highly hydrophilic and rather large molecules of HS1500 are not taken up in effective quantities and, therefore, cannot interfere with photosynthesis. The in vitro tests show that HS1500 has no inhibitory effect on photosystem II but operates as a weak, oxygen-consuming Hill acceptor at photosystem I. Hence, the results indicate that eco-physiological field experiments should focus more strongly on effects of HSs on extracellular features, such as reducing and red-shifting the underwater light field or influencing nutrient availability by cation exchange within the plankton network.
Collapse
Affiliation(s)
- Matthias Gilbert
- Institute of Biology, Department of Plant Physiology, University of Leipzig, Johannisallee 21-23, 04103, Leipzig, Germany.
| | - Hanno Bährs
- Aquacopa GmbH, Koppelbergstr. 4, 17166, Teterow, Germany
| | - Christian E W Steinberg
- Department of Biology, Freshwater and Stress Ecology, Humboldt-University Berlin, Arboretum, Späthstraße 80/81, 12437, Berlin, Germany
| | - Christian Wilhelm
- Institute of Biology, Department of Plant Physiology, University of Leipzig, Johannisallee 21-23, 04103, Leipzig, Germany.
| |
Collapse
|
4
|
Inhibition of Cyanobacterial Growth on a Municipal Wastewater Sidestream Is Impacted by Temperature. mSphere 2018; 3:mSphere00538-17. [PMID: 29507895 PMCID: PMC5830474 DOI: 10.1128/msphere.00538-17] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 02/07/2018] [Indexed: 01/21/2023] Open
Abstract
Cyanobacteria are viewed as promising platforms to produce fuels and/or high-value chemicals as part of so-called “biorefineries.” Their integration into wastewater treatment systems is particularly interesting because removal of the nitrogen and phosphorus in many wastewater streams is an expensive but necessary part of wastewater treatment. In this study, we evaluated strategies for cultivating Synechococcus sp. strain PCC 7002 on media comprised of two wastewater streams, i.e., treated secondary effluent supplemented with the liquid fraction extracted from sludge following anaerobic digestion. This strain is commonly used for metabolic engineering to produce a variety of valuable chemical products and product precursors (e.g., lactate). However, initial attempts to grow PCC 7002 under otherwise-standard conditions of light and temperature failed. We thus systematically evaluated alternative cultivation conditions and then used multiple methods to dissect the apparent toxicity of the media under standard cultivation conditions. Sidestreams in wastewater treatment plants can serve as concentrated sources of nutrients (i.e., nitrogen and phosphorus) to support the growth of photosynthetic organisms that ultimately serve as feedstock for production of fuels and chemicals. However, other chemical characteristics of these streams may inhibit growth in unanticipated ways. Here, we evaluated the use of liquid recovered from municipal anaerobic digesters via gravity belt filtration as a nutrient source for growing the cyanobacterium Synechococcus sp. strain PCC 7002. The gravity belt filtrate (GBF) contained high levels of complex dissolved organic matter (DOM), which seemed to negatively influence cells. We investigated the impact of GBF on physiological parameters such as growth rate, membrane integrity, membrane composition, photosystem composition, and oxygen evolution from photosystem II. At 37°C, we observed an inverse correlation between GBF concentration and membrane integrity. Radical production was also detected upon exposure to GBF at 37°C. However, the dose-dependent relationship between the GBF concentration and the lack of membrane integrity was abolished at 27°C. Immediate resuspension of strains in high levels of GBF showed markedly reduced oxygen evolution rates relative to those seen with the control. Taken together, the data indicate that one mechanism responsible for GBF toxicity to Synechococcus is the interruption of photosynthetic electron flow and subsequent phenomena. We hypothesize that this is likely due to the presence of phenolic compounds within the DOM. IMPORTANCE Cyanobacteria are viewed as promising platforms to produce fuels and/or high-value chemicals as part of so-called “biorefineries.” Their integration into wastewater treatment systems is particularly interesting because removal of the nitrogen and phosphorus in many wastewater streams is an expensive but necessary part of wastewater treatment. In this study, we evaluated strategies for cultivating Synechococcus sp. strain PCC 7002 on media comprised of two wastewater streams, i.e., treated secondary effluent supplemented with the liquid fraction extracted from sludge following anaerobic digestion. This strain is commonly used for metabolic engineering to produce a variety of valuable chemical products and product precursors (e.g., lactate). However, initial attempts to grow PCC 7002 under otherwise-standard conditions of light and temperature failed. We thus systematically evaluated alternative cultivation conditions and then used multiple methods to dissect the apparent toxicity of the media under standard cultivation conditions.
Collapse
|
5
|
Neilen AD, Hawker DW, O'Brien KR, Burford MA. Phytotoxic effects of terrestrial dissolved organic matter on a freshwater cyanobacteria and green algae species is affected by plant source and DOM chemical composition. CHEMOSPHERE 2017; 184:969-980. [PMID: 28655116 DOI: 10.1016/j.chemosphere.2017.06.063] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 05/12/2017] [Accepted: 06/15/2017] [Indexed: 06/07/2023]
Abstract
Here we link plant source phylogeny to its chemical characteristics and determine parameters useful for predicting DOM phytotoxicity towards algal monocultures. We found that DOM characterised using UV-visible spectroscopic indices and elemental analysis is useful for distinguishing DOM plant sources. Specifically, combined values of absorbance at 440 nm and coefficients for the spectral slope ratio, were used to distinguish between gymnosperm-leached DOM and that from angiosperms. In our bioassays, DOM leached from 4 g leaf L-1 resulted in over 40% inhibition of photosynthetic yield for the cyanobacterium, Cylindrospermopsis raciborskii, for eight of the nine plants tested. Significant variables for predicting inhibition of yield were DOM exposure time and plant source, or using an alternate model, exposure time and spectroscopic and elemental measures. Our study proposes spectroscopic indices which can estimate a plant source's contribution to aquatic DOM, may provide insights into ecological outcomes, such as phytotoxicity to algae. The cyanobacterium (C. raciborskii) was more sensitive to DOM than a green algae (Monoraphidium spp.), as identified in a subsequent dose-response experiment with five different DOM plant sources. Low level additions of angiosperm derived-DOM (i.e. 0.5 g L-1) were slight phytotoxic to Monoraphidium spp. causing 30% inhibition of yield, while C. raciborskii was not affected. Higher DOM additions (i.e. 2 g L-1) caused 100% inhibition of yield for C. raciborskii, while Monoraphidium spp. inhibition remained under 30%. The divergence in algal sensitivity to DOM indicates that in aquatic systems, DOM derived from catchment vegetation has the potential to affect algal assemblages.
Collapse
Affiliation(s)
- Amanda D Neilen
- Australian Rivers Institute & Griffith School of Environment, Griffith University, Nathan, QLD, Australia.
| | - Darryl W Hawker
- Griffith School of Environment, Griffith University, Nathan, QLD, Australia
| | - Katherine R O'Brien
- School of Chemical Engineering, Faculty of Engineering, Architecture and Information Technology, University of Queensland, St Lucia, QLD, Australia
| | - Michele A Burford
- Australian Rivers Institute & Griffith School of Environment, Griffith University, Nathan, QLD, Australia
| |
Collapse
|
6
|
Zhao D, Cao X, Huang R, Zeng J, Shen F, Xu H, Wang S, He X, Yu Z. The heterogeneity of composition and assembly processes of the microbial community between different nutrient loading lake zones in Taihu Lake. Appl Microbiol Biotechnol 2017; 101:5913-5923. [PMID: 28523397 DOI: 10.1007/s00253-017-8327-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Revised: 05/02/2017] [Accepted: 05/05/2017] [Indexed: 11/29/2022]
Abstract
To investigate the differences in the microbial community composition and assembly process in two lake zones (Meiliang Bay (MLB) and Xukou Bay (XKB) in Taihu Lake, China) with different nutrient loadings, water samples were collected. Both the 16S ribosomal RNA (rRNA) gene for the bacterial community and the 18S rRNA gene for the microeukaryote community were investigated using the Illumina second-generation sequencing platform (2 × 250 paired-end). The results indicated that both the bacterioplankton and microeukaryote community composition derived from the two lake zones were significantly different. Significantly higher operational taxonomic unit (OTU) richness (P < 0.01) and phylogenetic diversity (P < 0.05) were found for the bacterioplankton community of MLB. However, a comparable alpha diversity was found between the microeukaryote communities of MLB and XKB (P > 0.05). Environmental factors significantly affected the community compositions in XKB for both the bacterioplankton and microeukaryotes. However, they did not significantly influence the microbial community composition in MLB, except for a weak correlation between dissolved organic carbon (DOC) and the microeukaryote community. The microbial communities tended to be more phylogenetically clustered than expected by chance in the two lake zones. Moreover, the results of the phylogenetic structure suggest that deterministic processes played overwhelming roles in driving the assembly of both the bacterioplankton and microeukaryote community in XKB.
Collapse
Affiliation(s)
- Dayong Zhao
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China. .,College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, China. .,Department of Microbiology and Plant Biology, University of Oklahoma, Norman, OK, USA.
| | - Xinyi Cao
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China.,College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, China.,State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Rui Huang
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China.,College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, China.,State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Jin Zeng
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Feng Shen
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China.,College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, China.,State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Huimin Xu
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China.,College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, China.,State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Sichen Wang
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China.,College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, China.,State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Xiaowei He
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China.,College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, China.,State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Zhongbo Yu
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing, 210098, China. .,College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, China.
| |
Collapse
|
7
|
Su JF, Ma M, Wei L, Ma F, Lu JS, Shao SC. Algicidal and denitrification characterization of Acinetobacter sp. J25 against Microcystis aeruginosa and microbial community in eutrophic landscape water. MARINE POLLUTION BULLETIN 2016; 107:233-239. [PMID: 27126181 DOI: 10.1016/j.marpolbul.2016.03.066] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 03/24/2016] [Accepted: 03/30/2016] [Indexed: 06/05/2023]
Abstract
Acinetobacter sp. J25 exhibited good denitrification and high algicidal activity against toxic Microcystis aeruginosa. Response surface methodology (RSM) experiments showed that the maximum algicidal ratio occurred under the following conditions: temperature, 30.46°C; M. aeruginosa density, 960,000cellsmL(-1); and inoculum, 23.75% (v/v). Of these, inoculum produced the maximum effect. In the eutrophic landscape water experiment, 10% bacterial culture was infected with M. aeruginosa cells in the landscape water. After 24days, the removal ratios of nitrate and chlorophyll-a were high, 100% and 87.86%, respectively. The denitrification rate was approximately 0.118mgNO3(-)-N·L(-1)·h(-1). Moreover, the high-throughput sequencing result showed that Acinetobacter sp. J25 was obviously beneficial for chlorophyll-a and nitrate removal performance in the eutrophic landscape water treatment. Therefore, strain J25 is promising for the simultaneous removal of chlorophyll-a and nitrate in the eutrophic landscape water treatment.
Collapse
Affiliation(s)
- Jun Feng Su
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China; State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, People's Republic of China.
| | - Min Ma
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Li Wei
- State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, People's Republic of China.
| | - Fang Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, People's Republic of China
| | - Jin Suo Lu
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| | - Si Cheng Shao
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, People's Republic of China
| |
Collapse
|
8
|
Nam SH, An YJ. Cell size and the blockage of electron transfer in photosynthesis: proposed endpoints for algal assays and its application to soil alga Chlorococcum infusionum. CHEMOSPHERE 2015; 128:85-95. [PMID: 25666176 DOI: 10.1016/j.chemosphere.2015.01.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 12/23/2014] [Accepted: 01/06/2015] [Indexed: 05/28/2023]
Abstract
This study evaluated multiple endpoints of algal assays to identify sensitive and easy to use endpoints that could be applied to evaluate algal toxicity in metal-polluted soil extracts. Soil algae play an important role in trophic levels; thus, Chlorococcum infusionum was selected as the test species. Soil extracts were used because they might help identify potential soil retention and ecological hazards caused by pollutants that are present in the soil aqueous phase. The multi-endpoints measured were growth yield, photosynthetic activities, and cell viabilities. Nine parameters were measured to evaluate photosynthetic activity; namely, specific energy fluxes per quinone A-reducing photosystem II reaction center (absorption flux, trapped energy flux, electron transport flux, and dissipated energy flux per reaction center), quantum yields (maximum quantum yield of primary photochemistry, quantum yield of electron transport, quantum yield of energy dissipation, and average quantum yield of primary photochemistry), and the blockage of electron transfer from the reaction center to the quinone pool. Cell viability was evaluated by measuring cell size, cell granularity, and the autofluorescence of chlorophyll using flow cytometry. The results showed that heavy metals reduced growth yield, cell viability, and the photosynthetic activity of C. infusionum in soil extracts. Out of the 13 tested endpoints, the blockage of electron transfer from the reaction center to the quinone pool and cell size represented the most sensitive endpoints. We propose that both endpoints should be measured, along with conventional growth yield, to determine the effect of soil pollutants and to lower pollutant concentrations in soils.
Collapse
Affiliation(s)
- Sun-Hwa Nam
- Department of Environmental Health Science, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701, Republic of Korea
| | - Youn-Joo An
- Department of Environmental Health Science, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701, Republic of Korea.
| |
Collapse
|
9
|
Laue P, Bährs H, Chakrabarti S, Steinberg CEW. Natural xenobiotics to prevent cyanobacterial and algal growth in freshwater: contrasting efficacy of tannic acid, gallic acid, and gramine. CHEMOSPHERE 2014; 104:212-220. [PMID: 24332729 DOI: 10.1016/j.chemosphere.2013.11.029] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2013] [Revised: 11/06/2013] [Accepted: 11/11/2013] [Indexed: 06/03/2023]
Abstract
Allelochemical action against planktonic phototrophs is one central issue in freshwater ecology and quality management. To determine some basic mechanisms of this toxic action, we exposed the coccal green alga, Desmodesmus armatus, and the coccal cyanobacterium, Microcystis aeruginosa, in a batch culture well-supplied with carbon dioxide to increasing concentrations of the polyphenols tannic acid and gallic acid and the alkaloid gramine. The phototrophs were checked after 2d and at the end of the culture for biomass-based growth rates, cell volume, maximum quantum yield of photosystem II (ΦPSIImax), chlorophyll a content (chla) after 2d and at the end of the culture, and lipid peroxidation only at the end of the culture. During the culture, the pH rose from 7.64 to 10.95, a pH characteristic of eutrophic freshwater bodies during nuisance algal blooms. All xenobiotics reduced the growth rate, ΦPSIImax, and chla during the first 2d with M. aeruginosa being more sensitive to the polyphenols than D. armatus. The efficacy of the polyphenols declined with increasing pH, indicating potential polymerization and corresponding reduced bioavailability of the polyphenols. In contrast to the polyphenols, gramine increased its toxic action over time, independent of the prevailing pH. All exposures caused slight to severe lipid peroxidation (LPO) in the phototrophs. Hence, one mechanism of growth inhibition may be oxidative stress-mediated reduction in photosynthesis. The presented results suggest that in successful field trials with leachate, the prevailing environmental conditions may inactivate polyphenols and xenobiotics other than polyphenols may be more effective.
Collapse
Affiliation(s)
- Pauline Laue
- Lausitz University of Applied Sciences, Großenhainer Straße 57, 01968 Senftenberg, Germany; Humboldt-Universität zu Berlin, Laboratory of Freshwater & Stress Ecology, Arboretum, Späthstr. 80/81, 12437 Berlin, Germany
| | - Hanno Bährs
- Humboldt-Universität zu Berlin, Laboratory of Freshwater & Stress Ecology, Arboretum, Späthstr. 80/81, 12437 Berlin, Germany
| | - Shumon Chakrabarti
- Humboldt-Universität zu Berlin, Laboratory of Freshwater & Stress Ecology, Arboretum, Späthstr. 80/81, 12437 Berlin, Germany; Leibniz Institute for Agricultural Engineering Potsdam-Bornim, Max-Eyth-Allee 100, 14469 Potsdam, Germany
| | - Christian E W Steinberg
- Humboldt-Universität zu Berlin, Laboratory of Freshwater & Stress Ecology, Arboretum, Späthstr. 80/81, 12437 Berlin, Germany.
| |
Collapse
|
10
|
Bährs H, Putschew A, Steinberg CEW. Toxicity of hydroquinone to different freshwater phototrophs is influenced by time of exposure and pH. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2013; 20:146-154. [PMID: 22956111 DOI: 10.1007/s11356-012-1132-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Accepted: 08/20/2012] [Indexed: 06/01/2023]
Abstract
The interaction of natural organic matter with phytoplankton communities in freshwater ecosystems is an intensively studied subject matter. Previous studies showed that apparently plant-derived phenols were able to inhibit algal and cyanobacterial growth. Furthermore, it was also assumed that humic substances (HS), which comprise the major part of dissolved organic carbon in freshwater ecosystems, directly interact with freshwater phototrophs. For example, quinoid building blocks of HS were thought to be algicidal. To identify key environmental variable for the toxic action of potential quinone algicides, we tested the toxicity of hydroquinone (HQ) to different eukaryotic and prokaryotic freshwater phototrophs in terms of growth performance and investigated also the effect of HQ oxidation at different pH values on its algicidal potential. It was shown that cyanobacterial species were much more susceptible to hydroquinone than coccal green algal species were, with Microcystis aeruginosa being the most sensitive species by far. In addition, it was obvious that the aging of hydroquinone-stock solution at pH 11 led to polymerization and, by this process, to a total loss of toxicity; whereas the algicidal potential sustained if the polyphenol was kept at pH 7. Since most lakes with heavy blooms of phototrophs possess pH values clearly above 7.0, it is questionable, if polyphenols in general and quinones in particular are the effective chemicals and if litter and straw leachates are applied as means to combat algal and cyanobacterial blooms.
Collapse
Affiliation(s)
- Hanno Bährs
- Department of Biology, Freshwater and Stress Ecology, Humboldt-Universität zu Berlin, Späthstr 80/81, 12437 Berlin, Germany.
| | | | | |
Collapse
|