1
|
Medina-Armijo C, Yousef I, Berná A, Puerta A, Esteve-Núñez A, Viñas M, Prenafeta-Boldú FX. Characterization of melanin from Exophiala mesophila with the prospect of potential biotechnological applications. FRONTIERS IN FUNGAL BIOLOGY 2024; 5:1390724. [PMID: 38812984 PMCID: PMC11134573 DOI: 10.3389/ffunb.2024.1390724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 04/25/2024] [Indexed: 05/31/2024]
Abstract
Introducion Fungal melanin is an underexplored natural biomaterial of great biotechnological interest in different areas. This study investigated the physical, chemical, electrochemical, and metal-binding properties of melanin extracted from the metallotolerant black fungus Exophiala mesophila strain IRTA-M2-F10. Materials and methods Specific inhibitory studies with tricyclazole and biochemical profiling of whole cells by synchrotron radiation-based Fourier-transform infrared spectral microscopy (SR-FTIRM) were performed. An optimized extraction protocol was implemented, and purified fungal melanin was characterized using an array of spectrophotometric techniques (UV-Vis, FTIR, and EPR) and by cyclic voltammetry (CV) experiments. The metal-binding capacity of melanin extracts was also assessed by using Cr(VI) as a model heavy metal. Results Inhibitory studies indicated that 1,8-dihydroxynaphthalene may be the main precursor molecule of E. mesophila melanin (DHN-melanin). The biochemical characterization of fungal melanin extracts were benchmarked against those from two melanins comprising the precursor molecule L-3,4-dihydroxiphenylalanine (DOPA-melanin): extracts from the ink of the cephalopod Sepia officinalis and DOPA-melanin synthesized in the laboratory. The CV results of melanin extracts incubated with and without cell suspensions of the electroconductive bacterium Geobacter sulfurreducens were indicative of novel semiquinone/hydroquinone redox transformations specific for each melanin type. These interactions may play an important role in cation exchange for the adsorption of metals and in microbial interspecies electron transfer processes. Discussion The obtained results provided further evidence for the DHN-nature of E. mesophila melanin. The FTIR profiling of melanin extracts exposed to Cr(VI), compared to unexposed melanin, resulted in useful information on the distinct surface-binding properties of fungal melanin. The parameters of the Langmuir and Freundlicht isotherms for the adsorption of Cr(VI) were determined and compared to bibliographic data. Altogether, the inherent properties of fungal melanin suggest its promising potential as a biomaterial for environmental applications.
Collapse
Affiliation(s)
- Cristy Medina-Armijo
- Program of Sustainability in Biosystems, Institute of Agrifood Research and Technology (IRTA), Caldes de Montbui, Catalonia, Spain
- Faculty of Pharmacy and Food Sciences, University of Barcelona, Catalonia, Spain
| | - Ibraheem Yousef
- MIRAS Beamline, ALBA Synchrotron Light Source, Cerdanyola del Vallés, Catalonia, Spain
| | | | - Anna Puerta
- Program of Sustainability in Biosystems, Institute of Agrifood Research and Technology (IRTA), Caldes de Montbui, Catalonia, Spain
| | - Abraham Esteve-Núñez
- Department of Chemical Engineering, Universidad de Alcalá, Alcalá de Henares, Madrid, Spain
| | - Marc Viñas
- Program of Sustainability in Biosystems, Institute of Agrifood Research and Technology (IRTA), Caldes de Montbui, Catalonia, Spain
| | - Francesc X. Prenafeta-Boldú
- Program of Sustainability in Biosystems, Institute of Agrifood Research and Technology (IRTA), Caldes de Montbui, Catalonia, Spain
| |
Collapse
|
2
|
Huertas V, Jiménez A, Diánez F, Chelhaoui R, Santos M. Importance of Dark Septate Endophytes in Agriculture in the Face of Climate Change. J Fungi (Basel) 2024; 10:329. [PMID: 38786684 PMCID: PMC11122602 DOI: 10.3390/jof10050329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/22/2024] [Accepted: 04/30/2024] [Indexed: 05/25/2024] Open
Abstract
Climate change is a notable challenge for agriculture as it affects crop productivity and yield. Increases in droughts, salinity, and soil degradation are some of the major consequences of climate change. The use of microorganisms has emerged as an alternative to mitigate the effects of climate change. Among these microorganisms, dark septate endophytes (DSEs) have garnered increasing attention in recent years. Dark septate endophytes have shown a capacity for mitigating and reducing the harmful effects of climate change in agriculture, such as salinity, drought, and the reduced nutrient availability in the soil. Various studies show that their association with plants helps to reduce the harmful effects of abiotic stresses and increases the nutrient availability, enabling the plants to thrive under adverse conditions. In this study, the effect of DSEs and the underlying mechanisms that help plants to develop a higher tolerance to climate change were reviewed.
Collapse
Affiliation(s)
| | | | | | | | - Mila Santos
- Departamento de Agronomía, Escuela Superior de Ingeniería, Universidad de Almería, 04120 Almería, Spain; (V.H.); (A.J.); (F.D.); (R.C.)
| |
Collapse
|
3
|
Medina-Armijo C, Isola D, Illa J, Puerta A, Viñas M, Prenafeta-Boldú FX. The Metallotolerance and Biosorption of As(V) and Cr(VI) by Black Fungi. J Fungi (Basel) 2024; 10:47. [PMID: 38248956 PMCID: PMC10817489 DOI: 10.3390/jof10010047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 12/28/2023] [Accepted: 01/03/2024] [Indexed: 01/23/2024] Open
Abstract
A collection of 34 melanized fungi isolated previously from anthropogenic contaminated sites were assessed for their tolerance to toxic concentrations of As(V) and Cr(VI) anions. Three strains of the species Cyphellophora olivacea, Rhinocladiella similis, and Exophiala mesophila (Chaetothyriales) were identified as hyper-metallotolerant, with estimated IC50 values that ranged from 11.2 to 16.9 g L-1 for As(V) and from 2.0 to 3.4 g L-1 for Cr(VI). E. mesophila and R. similis were selected for subsequent assays on their biosorption capacity and kinetics under different pH values (4.0 and 6.5) and types of biomass (active and dead cells and melanin extracts). The fungal biosorption of As(V) was relatively ineffective, but significant removal of Cr(VI) was observed from liquid cultures. The Langmuir model with second-order kinetics showed maximum sorption capacities of 39.81 mg Cr6+ g-1 for R. similis and 95.26 mg Cr6+ g-1 for E. mesophila on a dry matter basis, respectively, while the kinetic constant for these two fungi was 1.32 × 10-6 and 1.39 × 10-7 g (mg Cr6+ min)-1. Similar experiments with melanin extracts of E. mesophila showed maximum sorption capacities of 544.84 mg Cr6+ g-1 and a kinetic constant of 1.67 × 10-6 g (mg Cr6+ min)-1. These results were compared to bibliographic data, suggesting that metallotolerance in black fungi might be the result of an outer cell-wall barrier to reduce the diffusion of toxic metals into the cytoplasm, as well as the inner cell wall biosorption of leaked metals by melanin.
Collapse
Affiliation(s)
- Cristy Medina-Armijo
- Program of Sustainability in Biosystems, Institute of Agrifood Research and Technology (IRTA), 08140 Caldes de Montbui, Spain
- Faculty of Pharmacy and Food Sciences, University of Barcelona, 08028 Barcelona, Spain
| | - Daniela Isola
- Department of Economics, Engineering, Society and Business Organization (DEIM), University of Tuscia, 01100 Viterbo, Italy
| | - Josep Illa
- Department of Computing and Industrial Engineering, University of Lleida, 25001 Lleida, Spain
| | - Anna Puerta
- Program of Sustainability in Biosystems, Institute of Agrifood Research and Technology (IRTA), 08140 Caldes de Montbui, Spain
| | - Marc Viñas
- Program of Sustainability in Biosystems, Institute of Agrifood Research and Technology (IRTA), 08140 Caldes de Montbui, Spain
| | - Francesc X. Prenafeta-Boldú
- Program of Sustainability in Biosystems, Institute of Agrifood Research and Technology (IRTA), 08140 Caldes de Montbui, Spain
| |
Collapse
|
4
|
Cao G, Li X, Zhang C, Xiong Y, Li X, Li T, He S, Cui Z, Yu J. Physiological response mechanism of heavy metal-resistant endophytic fungi isolated from the roots of Polygonatum kingianum. ENVIRONMENTAL MICROBIOLOGY REPORTS 2023; 15:568-581. [PMID: 37604512 PMCID: PMC10667662 DOI: 10.1111/1758-2229.13194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 08/09/2023] [Indexed: 08/23/2023]
Abstract
This study aims to evaluate the tolerance of endophytic fungi isolated from the fibrous roots of Polygonatum kingianum to arsenic (As) and cadmium (Cd) and their physiological response mechanisms. Five isolated strains were obtained with EC50 values for As(V) ranging from 421 to 1281 mg/L, while the other three strains tolerated Cd(II) with an EC50 range of 407-1112 mg/L. Morphological and molecular identification indicated that these eight strains were Cladosporium spp. belonging to dark septate endophytes (DSEs). The contents of metal ions in mycelium sharply increased, reaching 38.87 mg/kg for strain MZ-11 under As(V) stress and 0.33 mg/kg for fungus PR-2 under Cd(II). The physiological response revealed that the biomass decreased with increasing concentrations of As(V) or Cd(II), and the activity of superoxide dismutase significantly improved under the corresponding EC50 -concentration As/Cd of the strains, as well as the contents of antioxidant substances, including metallothionein, glutathione, malondialdehyde, melanin, and proline. Taken together, the filamentous fungi of Cladosporium spp. accounted for a high proportion of fungi isolated from the fibrous roots of P. kingianum and had a strong capacity to tolerate As(V) or Cd(II) stress by improving antioxidase activities and the content of antioxidant substances, and immobilization of metal ions in hyphae.
Collapse
Affiliation(s)
- Guan‐Hua Cao
- School of Chinese Materia MedicaYunnan University of Chinese MedicineKunmingChina
| | - Xiao‐Gang Li
- School of Chinese Materia MedicaYunnan University of Chinese MedicineKunmingChina
| | - Chen‐Rui Zhang
- School of Chinese Materia MedicaYunnan University of Chinese MedicineKunmingChina
| | - Yi‐Ran Xiong
- School of Chinese Materia MedicaYunnan University of Chinese MedicineKunmingChina
| | - Xue Li
- School of Chinese Materia MedicaYunnan University of Chinese MedicineKunmingChina
| | - Tong Li
- School of Chinese Materia MedicaYunnan University of Chinese MedicineKunmingChina
| | - Sen He
- School of Chinese Materia MedicaYunnan University of Chinese MedicineKunmingChina
- Department of Environmental HealthUniversity of Fukui School of Medical SciencesFukuiJapan
| | - Zheng‐Guo Cui
- Department of Environmental HealthUniversity of Fukui School of Medical SciencesFukuiJapan
| | - Jie Yu
- School of Chinese Materia MedicaYunnan University of Chinese MedicineKunmingChina
| |
Collapse
|
5
|
Ban Y, Tan J, Xiong Y, Mo X, Li W, Jia C, Ding Y, Xu Z. The responses and detoxification mechanisms of dark septate endophytes (DSE), Exophiala salmonis, to CuO nanoparticles. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:13773-13787. [PMID: 36149553 DOI: 10.1007/s11356-022-23099-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Accepted: 09/14/2022] [Indexed: 06/16/2023]
Abstract
To understand the tolerance mechanisms of dark septate endophytes (DSE), Exophiala salmonis, to CuO nanoparticles (CuO-NPs) with different sizes (40 and 150 nm), we investigated the morphology, antioxidant response, Cu subcellular distribution, and the melanin gene expression in the mycelia of E. salmonis. E. salmonis was cultured in liquid and solid media under the stress of increasing CuO-NP concentrations (0, 50, 100, 150, and 250 mg/L). Results showed that (1) E. salmonis showed good CuO-NP tolerance, and the tolerance to CuO-NPs at 150 nm was stronger than that at 40 nm. A large number of agglomeration structures were observed on the mycelia surface with the exception of 50 mg/L CuO-NPs with a diameter of 150 nm. (2) CuO-NP stress significantly stimulated the production of antioxidant enzymes, particularly the CuO-NPs with small particle size (40 nm). (3) Cu uptaken by E. salmonis increased proportionally with the increase of CuO-NP concentration in the medium. More than 80% Cu was absorbed in cell wall of mycelia treated with a small particle size (40 nm). (4) FTIR analysis revealed that hydroxyl, amine, carboxyl, and phosphate groups were associated with CuO-NP binding regardless of particle size. (5) Fungal melanin content increased with the addition of CuO-NPs; the increase of melanin induced by CuO-NPs with small particle size (40 nm) was more significant. (6) The expression of 1,3,6,8-tetrahydroxynaphthalene reductase (Arp2) in the melanin synthesis pathway increased under the stress of CuO-NPs, and CuO-NPs with a small particle size (40 nm) caused a significant change in the expression level of Arp2 gene than those with a large particle size (150 nm). In conclusion, E. salmonis had a strong tolerance to CuO-NPs and mitigated the toxic effects of CuO-NPs through the antioxidant system, the expression of genes related to melanin synthesis, and the synthesis of melanin.
Collapse
Affiliation(s)
- Yihui Ban
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, Hubei, China
| | - Jiayuan Tan
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, Hubei, China
| | - Yang Xiong
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, Hubei, China
| | - Xiantong Mo
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, Hubei, China
| | - Wenxuan Li
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, Hubei, China
| | - Chenyue Jia
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, Hubei, China
| | - Yiwen Ding
- School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan, 430070, Hubei, China
| | - Zhouying Xu
- School of Civil Engineering and Architecture, Wuhan University of Technology, Wuhan, 430070, Hubei, China.
| |
Collapse
|
6
|
Potisek M, Likar M, Vogel-Mikuš K, Arčon I, Grdadolnik J, Regvar M. 1,8-dihydroxy naphthalene (DHN) - melanin confers tolerance to cadmium in isolates of melanised dark septate endophytes. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 222:112493. [PMID: 34265529 DOI: 10.1016/j.ecoenv.2021.112493] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 06/10/2021] [Accepted: 07/03/2021] [Indexed: 05/25/2023]
Abstract
The contribution of 1,8-dihydroxy naphthalene (DHN) melanin to cadmium (Cd) tolerance in two dark septate endophytes (DSE) of the genus Cadophora with different melanin content was investigated in vitro. The DSE isolate Cad#148 with higher melanin content showed higher tolerance to Cd than the less melanised Cad#149. Melanin synthesis was significantly reduced by Cd in both isolates with uninhibited melanin synthesis, in a dose-dependent manner. Inhibition of melanin synthesis by tricyclazole reduced the relative growth of Cad#148 exposed to Cd and did not affect Cad#149. Cd accumulation was not altered by tricyclazole in the two isolates, but it increased catalase and reduced glutathione reductase activity in more melanised Cad#148, indicating higher stress levels. In contrast, in Cad#149 the enzyme activity was less affected by tricyclazole, indicating a more pronounced role of melanin-independent Cd tolerance mechanisms. Cd ligand environment in fungal mycelia was analysed by extended EXAFS (X-ray absorption fine structure). It revealed that Cd was mainly bound to O- and S-ligands, including hydroxyl, carboxyl, phosphate and thiol groups. A similar proportion of S- and O- ligands (~35% and ~65%) were found in both isolates with uninhibited melanin synthesis. Among O-ligands two types with Cd-O-C- and Cd-O-P- coordination were identified. Tricyclazole altered Cd-O- ligand environment in both fungal isolates by reducing the proportion of Cd-O-C- and increasing the proportion of Cd-O-P coordination. DHN-melanin, among other tolerance mechanisms, significantly contributes to Cd tolerance in more melanised DSE fungi by immobilising Cd to hydroxyl groups and maintaining the integrity of the fungal cell wall.
Collapse
Affiliation(s)
- Mateja Potisek
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia.
| | - Matevž Likar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia
| | - Katarina Vogel-Mikuš
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia; Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
| | - Iztok Arčon
- Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia; University of Nova Gorica, Vipavska 13, POB 301, SI-5001 Nova Gorica, Slovenia
| | - Jože Grdadolnik
- National Institute of Chemistry, Hajdrihova 19, SI-1000 Ljubljana, Slovenia
| | - Marjana Regvar
- Department of Biology, Biotechnical Faculty, University of Ljubljana, Večna pot 111, SI-1000 Ljubljana, Slovenia
| |
Collapse
|
7
|
Colonization by dark septate endophytes improves the growth of Hedysarum scoparium under multiple inoculum levels. Symbiosis 2020. [DOI: 10.1007/s13199-020-00713-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
8
|
Berthelot C, Zegeye A, Gaber DA, Chalot M, Franken P, Kovács GM, Leyval C, Blaudez D. Unravelling the Role of Melanin in Cd and Zn Tolerance and Accumulation of Three Dark Septate Endophytic Species. Microorganisms 2020; 8:E537. [PMID: 32276491 PMCID: PMC7232325 DOI: 10.3390/microorganisms8040537] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 03/30/2020] [Accepted: 04/01/2020] [Indexed: 02/06/2023] Open
Abstract
Dark septate endophytes (DSEs) are often trace element (TE)-tolerant fungi and are abundant in TE-polluted environments. The production of melanin, a black polymer found in cell walls, was hypothesized by several authors to play a role in the TE tolerance of DSEs. To test this hypothesis, we established a series of experiments using albino strains and melanin inhibitors and examined the responses to Cd and Zn. Six DSEs belonging to genera Cadophora sp., Leptodontidium sp. and Phialophora mustea, were evaluated. The strains mainly produced 1,8-dihydroxynaphthalene (DHN) melanin whereas 3,4-dihydroxyphenylalanin melanin was also synthetized. Cd and Zn decreased melanin synthesis in most of the strains. A reduction in melanin concentration in hyphae through the use of tricyclazole, an inhibitor of DHN-melanin synthesis, did not reduce the tolerance of the strains to Cd and Zn. Similarly, albino mutants of Leptodontidium sp. were not more sensitive to Cd and Zn than the WT strain. Moreover, tricyclazole-treated colonies accumulated less Cd but more Zn compared to untreated colonies. The Cd and Zn contents of Leptodontidium albino strains were variable and similar to that of the WT. The results suggest that melanin production is not an important functional trait that contributes to Cd and Zn tolerance, but might contribute to Cd accumulation.
Collapse
Affiliation(s)
- Charlotte Berthelot
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France
- CTIFL, Centre de Carquefou, F-44483 Carquefou, France
| | - Asfaw Zegeye
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France
| | - Dalia A. Gaber
- Botany and Microbiology Department, Faculty of Sciences, Assiut University, Assiut 71515, Egypt
- Leibniz Institute for Vegetable and Ornamental Crops, 14979 Groβbeeren, Germany
| | - Michel Chalot
- Université de Bourgogne-Franche-Comté, CNRS, Laboratoire Chrono-Environnement, F-25211 Montbéliard, France
- Université de Lorraine, F-54000 Nancy, France
| | - Philipp Franken
- Leibniz Institute for Vegetable and Ornamental Crops, 14979 Groβbeeren, Germany
- Erfurt Research Centre for Horticultural Crops, University of Applied Sciences Erfurt, 99090 Erfurt, Germany
| | - Gábor M. Kovács
- Department of Plant Anatomy, Institute of Biology, Eötvös Loránd University, 1117 Budapest, Hungary
- Plant Protection Institute, Centre for Agricultural Research, 1022 Budapest, Hungary
| | - Corinne Leyval
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France
| | - Damien Blaudez
- Université de Lorraine, CNRS, LIEC, F-54000 Nancy, France
| |
Collapse
|
9
|
Species composition and colonization of dark septate endophytes are affected by host plant species and soil depth in the Mu Us sandland, northwest China. FUNGAL ECOL 2019. [DOI: 10.1016/j.funeco.2019.01.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
|
10
|
Screening of Rice Endophytic Biofertilizers with Fungicide Tolerance and Plant Growth-Promoting Characteristics. SUSTAINABILITY 2019. [DOI: 10.3390/su11041133] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The application of pesticides is unavoidable in conventional agricultural practice. To develop effective biofertilizers, bacterial strains with both pesticide tolerance and plant growth-promoting (PGP) traits were isolated for further testing. Seedlings of rice (Oryza sativa) were planted in soil with 1, 5, or 10 times the recommended rates of the fungicides etridiazole, metalaxyl, and tricyclazole. Endophytic bacteria were isolated from roots of rice seedlings. The bacterial 16S rDNA sequences and related PGP characteristics including potential nitrogen fixation, phosphorus-solubilizing and indole acetic acid (IAA) production ability were further examined. In all, 17 different strains were obtained from rice seedling roots; five strains with both nitrogen fixation potential and IAA production ability included Rhizobium larrymoorei E2, Bacillus aryabhattai E7, Bacillus aryabhattai MN1, Pseudomonas granadensis T6, and Bacillus fortis T9. Except for T9, all strains could tolerate two or more fungicides. We inoculated rice roots with the endophytic bacteria and all conferred rice growth-promoting ability. Bacillus aryabhattai MN1 was further tested and showed high tryptophan dose-dependent IAA production ability, tolerance towards etridiazole and metalaxyl application and should be considered a potential bacterial biofertilizer.
Collapse
|
11
|
Wu H, Shen J, Jiang X, Liu X, Sun X, Li J, Han W, Mu Y, Wang L. Bioaugmentation potential of a newly isolated strain Sphingomonas sp. NJUST37 for the treatment of wastewater containing highly toxic and recalcitrant tricyclazole. BIORESOURCE TECHNOLOGY 2018; 264:98-105. [PMID: 29793119 DOI: 10.1016/j.biortech.2018.05.071] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 05/17/2018] [Accepted: 05/18/2018] [Indexed: 06/08/2023]
Abstract
In order to develop an effective bioaugmentation strategy for the removal of highly toxic and recalcitrant tricyclazole from wastewater, a tricyclazole degrading strain was firstly successfully isolated and identified as Sphingomonas sp. NJUST37. In batch reactors, 100 mg L-1 tricyclazole could be completely removed within 102 h, which was accompanied by significant biomass increase, TOC and COD removal, as well as toxicity reduction. Chromatography analysis and density functional theory simulation indicated that monooxygenation occurred firstly, followed by triazole ring cleavage, decyanation reaction, hydration reaction, deamination, dihydroxylation and final mineralization reaction. Tricyclazole biodegradation condition by NJUST37 was optimized in terms of temperature, pH, tricyclazole concentration and additional carbon and nitrogen sources. After the inoculation of NJUST37 into a pilot-scale powdered activated carbon treatment tank treating real fungicide wastewater, tricyclazole removal efficiency increased to higher than 90%, demonstrating the great potential of NJUST37 for bioaugmentation particularly on tricyclazole biodegradation in practice.
Collapse
Affiliation(s)
- Haobo Wu
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Jinyou Shen
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
| | - Xinbai Jiang
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Xiaodong Liu
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Xiuyun Sun
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Jiansheng Li
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Weiqing Han
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Yang Mu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Lianjun Wang
- Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| |
Collapse
|
12
|
Berthelot C, Blaudez D, Leyval C. Differential growth promotion of poplar and birch inoculated with three dark septate endophytes in two trace element-contaminated soils. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2017; 19:1118-1125. [PMID: 28521510 DOI: 10.1080/15226514.2017.1328392] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Dark septate endophytes (DSEs) are abundant in stressful environments, including trace element (TE)-enriched soils. However, knowledge about the effects of DSEs on plant growth in such soils is poor compared to the well-known mycorrhizal fungi. The aim of this work was to evaluate the effects of three DSE strains isolated from TE-contaminated soils on the growth and mineral nutrition of Betula pendula and Populus tremula x alba grown on two contrasting TE-polluted soils. The three DSEs evenly colonized the two plant species in both soils. Nevertheless, plant responses to DSE inoculation varied from neutral to beneficial depending on soil properties. Depending on fungal strain and plant species, different factors seemed to contribute to plant growth promotion. Phialophora mustea Pr27 and Leptodontidium Pr30 decreased lipid peroxidation in birch shoots. Chlorophyll, K, and P concentrations increased in the shoots of Leptodontidium Pr30-inoculated trees, whereas Cd concentration decreased in Cadophora Fe06-inoculated birch. The absence of a general DSE-mediated plant growth-promoting behavior could represent a limiting factor for a generic use of DSEs in the tree-based phytomanagement of TE-contaminated soils. Our results suggest that the selection of strains adapted to particular edaphic conditions should not be overlooked within the framework of phytomanagement.
Collapse
Affiliation(s)
- Charlotte Berthelot
- a Université de Lorraine , CNRS, LIEC UMR 7360 , Vandoeuvre-les-Nancy , France
- b CNRS, Université de Lorraine, LIEC UMR7360 , Vandoeuvre-les-Nancy , France
| | - Damien Blaudez
- a Université de Lorraine , CNRS, LIEC UMR 7360 , Vandoeuvre-les-Nancy , France
- b CNRS, Université de Lorraine, LIEC UMR7360 , Vandoeuvre-les-Nancy , France
| | - Corinne Leyval
- a Université de Lorraine , CNRS, LIEC UMR 7360 , Vandoeuvre-les-Nancy , France
- b CNRS, Université de Lorraine, LIEC UMR7360 , Vandoeuvre-les-Nancy , France
| |
Collapse
|