Inhibitory mechanisms of Acacia mearnsii extracts on the growth of Microcystis aeruginosa

2015 ◽  
Vol 71 (6) ◽  
pp. 856-861 ◽  
Author(s):  
Zhibin Liu ◽  
Lirong Zhou ◽  
Dandan Liu ◽  
Qiyu Zhu ◽  
Wenqing Chen
Keyword(s):  
Cell Membrane ◽  
Microcystis Aeruginosa ◽  
Plant Extract ◽  
Algal Cell ◽  
Common Species ◽  
Cyanobacterial Blooms ◽  
Cell Membrane Permeability ◽  
Acacia Mearnsii ◽  
Inhibitory Mechanisms

Our previous work revealed that Acacia mearnsii extract can inhibit the growth of Microcystis aeruginosa, the common species forming toxic cyanobacterial blooms in eutrophic freshwater. In the present study, we demonstrated that this plant extract can significantly increase cell membrane permeability and Ca2+/Mg2+-ATPase activity on the membrane. Long-term exposure to concentrations of 20 ppm A. mearnsii extract led to algal cell membrane leakage or even lysis. Comparison of expression of three photosynthesis-related genes (rbcL, psaB and psbD) in M. aeruginosa with and without plant extract treatment revealed that their expression was remarkably reduced in the presence of the extract. Down-regulation of photosynthesis-related genes could indicate the inhibition of the photosynthetic process. Thus, our results suggested that both photosynthetic systems and membranes of M. aeruginosa are potentially damaged by A. mearnsii extract.

THE INFLUENCE OF pH ON ALGAL CELL MEMBRANE PERMEABILITY AND ITS IMPLICATIONS FOR THE UPTAKE OF LIPOPHILIC METAL COMPLEXES1

2012 ◽  
Vol 48 (2) ◽  
pp. 293-302 ◽  
Author(s):  
Michel Lavoie ◽  
Séverine Le Faucheur ◽  
Amiel Boullemant ◽  
Claude Fortin ◽  
Peter G. C. Campbell
Keyword(s):  
Cell Membrane ◽  
Membrane Permeability ◽  
Algal Cell ◽  
Cell Membrane Permeability ◽  
Influence Of Ph

scholarly journals Determination of the Role of Microcystis aeruginosa in Toxin Generation Based on Phosphoproteomic Profiles

Toxins ◽  
2018 ◽  
Vol 10 (7) ◽  
pp. 304 ◽  
Author(s):  
Jiangqi Qu ◽  
Liping Shen ◽  
Meng Zhao ◽  
Wentong Li ◽  
Chengxia Jia ◽  
...  
Keyword(s):  
Microcystis Aeruginosa ◽  
Physiological Activity ◽  
Redox Homeostasis ◽  
Common Species ◽  
Cyanobacterial Blooms ◽  
Phosphorylation Sites ◽  
Protein Protein Interaction ◽  
Toxin Protein

Microcystis aeruginosa is the most common species responsible for toxic cyanobacterial blooms and is considered a significant contributor to the production of cyanotoxins, particularly the potent liver toxins called microcystins. Numerous studies investigating Microcystis spp. blooms have revealed their deleterious effects in freshwater environments. However, the available knowledge regarding the global phosphoproteomics of M. aeruginosa and their regulatory roles in toxin generation is limited. In this study, we conducted comparative phosphoproteomic profiling of non-toxic and toxin-producing strains of M. aeruginosa. We identified 59 phosphorylation sites in 37 proteins in a non-toxic strain and 26 phosphorylation sites in 18 proteins in a toxin-producing strain. The analysis of protein phosphorylation abundances and functions in redox homeostasis, energy metabolism, light absorption and photosynthesis showed marked differences between the non-toxic and toxin-producing strains of M. aeruginosa, indicating that these processes are strongly related to toxin generation. Moreover, the protein-protein interaction results indicated that BJ0JVG8 can directly interact with the PemK-like toxin protein B0JQN8. Thus, the phosphorylation of B0JQN8 appears to be associated with the regulatory roles of toxins in physiological activity.

scholarly journals 2-Phenylethyl Isothiocyanate Exerts Antifungal Activity against Alternaria alternata by Affecting Membrane Integrity and Mycotoxin Production

Toxins ◽  
2020 ◽  
Vol 12 (2) ◽  
pp. 124
Author(s):  
Miao Zhang ◽  
Yongcai Li ◽  
Yang Bi ◽  
Tiaolan Wang ◽  
Yupeng Dong ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Alternaria Alternata ◽  
Membrane Integrity ◽  
Black Spot ◽  
Cell Membrane Permeability ◽  
Pear Fruit ◽  
Cell Membrane Integrity ◽  
Inhibitory Mechanisms ◽  
Phenylethyl Isothiocyanate

Black spot caused by Alternaria alternata is one of the important diseases of pear fruit during storage. Isothiocyanates are known as being strong antifungal compounds in vitro against different fungi. The aim of this study was to assess the antifungal effects of the volatile compound 2-phenylethyl isothiocyanate (2-PEITC) against A. alternata in vitro and in pear fruit, and to explore the underlying inhibitory mechanisms. The in vitro results showed that 2-PEITC significantly inhibited spore germination and mycelial growth of A. alternata—the inhibitory effects showed a dose-dependent pattern and the minimum inhibitory concentration (MIC) was 1.22 mM. The development of black spot rot on the pear fruit inoculated with A. alternata was also significantly decreased by 2-PEITC fumigation. At 1.22 mM concentration, the lesion diameter was only 39% of that in the control fruit at 7 days after inoculation. Further results of the leakage of electrolyte, increase of intracellular OD260, and propidium iodide (PI) staining proved that 2-PEITC broke cell membrane permeability of A. alternata. Moreover, 2-PEITC treatment significantly decreased alternariol (AOH), alternariolmonomethyl ether (AME), altenuene (ALT), and tentoxin (TEN) contents of A. alternata. Taken together, these data suggest that the mechanisms underlying the antifungal effect of 2-PEITC against A. alternata might be via reduction in toxin content and breakdown of cell membrane integrity.

scholarly journals Algicidal Molecular Mechanism and Toxicological Degradation of Microcystis aeruginosa by White-Rot Fungi

Toxins ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 406
Author(s):  
Guoming Zeng ◽  
Pei Gao ◽  
Jiale Wang ◽  
Jinxi Zhang ◽  
Maolan Zhang ◽  
...  
Keyword(s):  
Molecular Mechanism ◽  
Phanerochaete Chrysosporium ◽  
Microcystis Aeruginosa ◽  
Algal Cell ◽  
White Rot Fungi ◽  
White Rot ◽  
Toxin Gene ◽  
Metabolic System ◽  
Inhibitory Mechanisms ◽  
Cell Inhibition

Current research on the inhibition of Microcystis aeruginosa growth is primarily focused on algae-lysing bacteria, and few studies have investigated the inhibitory mechanisms by which fungi affect it at the molecular level. A comparative analysis of the effects of Phanerochaete chrysosporium on the expression of the algal cell antioxidant protease synthesis gene prx, the biological macromolecule damage and repair genes recA, grpE, and fabZ, and the photosynthesis system-related genes psaB, psbD1 and rbcL, as well as genes for algal toxin synthesis mcyB, were performed to elucidate the molecular mechanism of Phanerochaete chrysosporium against Microcystis aeruginosa cells. RT-qPCR technology was used to study the molecular mechanism of algal cell inhibition by Phanerochaete chrysosporium liquid containing metabolites of Phanerochaete chrysosporium, Phanerochaete chrysosporium supernatant and Phanerochaete chrysosporium inactivated via high temperature sterilization at the gene expression level. Compared with the control, the chlorophyll-a contents dropped, and the recA, grpE, fabZ, and prx increased, but the psaB, psbD1, rbcL and mcyB showed that they were significantly reduced, which indicated that Phanerochaete chrysosporium can not only effectively destroy algal cells, but they may also reduce the expression of the Microcystis aeruginosa toxin gene and significantly block the metabolic system underlying the growth of algal cells and the synthesis of microcystins.

Growth inhibition of Microcystis aeruginosa by white-rot fungus Lopharia spadicea

2010 ◽  
Vol 62 (2) ◽  
pp. 317-323 ◽  
Author(s):  
Q. Wang ◽  
M. Su ◽  
W. Zhu ◽  
X. Li ◽  
Y. Jia ◽  
...  
Keyword(s):  
Chlorophyll A ◽  
Microcystis Aeruginosa ◽  
Algal Cell ◽  
Influence Factors ◽  
Cyanobacterial Blooms ◽  
White Rot ◽  
White Rot Fungus ◽  
Algal Strain ◽  
Initial Ph ◽  
Chlorophyll A Content

Harmful cyanobacterial blooms cause water deterioration and threaten human health. It is necessary to remove harmful cyanobacteria with useful methods. A bio-treatment may be one of the best ways to do this. A strain of specific white-rot fungus, Lopharia spadicea, with algicidal ability was isolated. Its algicidal ability on algae under various conditions was determined using three main influence factors: initial chlorophyll-a content, initial pH, and algal cell mixture. The  result showed that the chlorophyll-a content of Microcystis aeruginosa FACHB-912, Oocystis borgei FACHB-1108, and Microcystis flos-aquae FACHB-1028 decreased from 798 ± 13, 756 ± 40, and 773 ± 24 μg/L to 0 within 39 h. L. spadicea could also remove more than 95% chlorophyll-a when initial chlorophyll-a content increased from 397 ± 13 to 2,132 ± 4 μg/L. Moreover, the strain has great removal ability under a broad initial pH range of 5.5 to 9.5. The chlorophyll-a content of the three algal strain mixtures decreased from about 672 ± 23 μg/L to 0 within 45 h. After superoxide dismutase (SOD) and malondialdehyde (MAD) were assessed in a co-culture of L. spadicea, it was observed that an increase in MAD content was correlated with the decrease in chlorophyll-a content of M. aeruginosa FACHB-912. This result suggested that the algae was not only greatly inhibited but also severely damaged by the fungus.

scholarly journals The Mechanism Insight Into the Inhibitory Effect of Artemisinin Sustained-release Inhibitors With Different Particle Sizes on Microcystis aeruginosa

2021 ◽  
Author(s):  
Zhiyun Jiang ◽  
lixiao Ni ◽  
Xianglan Li ◽  
Chu Xu ◽  
Xuqing Chen ◽  
...  
Keyword(s):  
Cell Membrane ◽  
Sustained Release ◽  
Chlorophyll A ◽  
Microcystis Aeruginosa ◽  
Harmful Algal Blooms ◽  
Algal Blooms ◽  
Algal Cell ◽  
Inhibitory Effect ◽  
Inhibitory Mechanism ◽  
Irreversible Damage

Abstract Environment-friendly algaecides based on allelopathy have been widely used to control harmful algal blooms. In this research, micro nano scale artemisinin sustained-release algal inhibitor was prepared, the optimal preparation conditions were explored and the inhibitory mechanism of artemisinin algaecides was perfected. The results showed that when the particle size of artemisinin sustained-release microspheres (ASMs) was 2/10000 of artemisinin sustained-release granules (ASGs), the inhibitory effect was more remarkable. The optimal concentration of ASMs was 0.2 g L-1, and the inhibitory effect reached 99% on the 10th day; The algae density and chlorophyll-a both showed a downward trend, indicating that ASGs and ASMs could promote the degradation of chlorophyll-a; The inhibition rate of ASGs was faster than that of ASMs on the 4th day, and the inhibitory effect of ASMs was more significant after the 5th day. The activities of superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) increased rapidly at first and then decreased, which indicated that ASGs and ASMs caused oxidative damage to Microcystis aeruginosa (M. aeruginosa) and inhibited the activity of antioxidant enzymes. Furthermore, the content of the oxygen free radical (O2-) and malondialdehyde (MDA) continued to rise after the 5th day, the protein, nucleic acid and conductivity in the culture medium increased. These results showed that lipid peroxidation occurred in the algal cell membrane, and the permeability of the membrane increased. In summary, the ASMs had significant continuous inhibitory effect while the ASGs had better short-term effect. The main inhibitory mechanism of artemisinin algaecides is the irreversible damage of cell membrane.

scholarly journals Antifungal Activity of Essential Oil Compounds (Geraniol and Citral) and Inhibitory Mechanisms on Grain Pathogens (Aspergillus flavus and Aspergillus ochraceus)

Molecules ◽  
2018 ◽  
Vol 23 (9) ◽  
pp. 2108 ◽  
Author(s):  
Xi Tang ◽  
Ye-Lin Shao ◽  
Ya-Jie Tang ◽  
Wen-Wen Zhou
Keyword(s):  
Antifungal Activity ◽  
Essential Oil ◽  
Cell Membrane ◽  
Membrane Permeability ◽  
Cell Membrane Permeability ◽  
Aspergillus Ochraceus ◽  
Ros Generation ◽  
Inhibitory Mechanisms ◽  
Preservation Method ◽  
Essential Oil Compounds

The grain contamination by Aspergillus spp. has been a serious issue. This study exhibited the excellent antifungal effects of the essential oil compounds (EOCs) geraniol and citral against common grain pathogens (A. flavus and A. ochraceus) in vitro and in situ. The inhibitory mechanisms were also evaluated from the perspective of cell membrane permeability, reactive oxygen species (ROS) generation, and Aspergillus spp. growth-related gene expression. Meanwhile, the combined effects of EOCs in the vapor phase and modified atmosphere packaging (MAP) were examined to find an alternative preservation method for controlling Aspergillus spp. The results indicated that citral exhibited the antifungal activity mainly by downregulating the sporulation- and growth-related genes for both pathogens. Geraniol displayed inhibitory effectiveness against A. flavus predominantly by inducing the intracellular ROS accumulation and showed toxicity against A. ochraceus principally by changing cell membrane permeability. Furthermore, the synthetic effects of EOCs and MAP (75% CO2 and 25% N2) induced better grain quality than the current commercial fumigant AlP. These findings reveal that EOCs have potential to be a novel grain preservative for further application.

Sarcolemmal permeability changes during early myocardial anoxia

1978 ◽  
Vol 36 (2) ◽  
pp. 642-643
Author(s):  
M. Ashraf ◽  
L. Landa ◽  
L. Nimmo ◽  
C. M. Bloor
Keyword(s):  
Cell Membrane ◽  
Membrane Permeability ◽  
Coronary Artery Occlusion ◽  
Artery Occlusion ◽  
Cell Membrane Permeability ◽  
Enzyme Release ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Sarcolemmal Permeability ◽  
Membrane Changes

Following coronary artery occlusion, the myocardial cells lose intracellular enzymes that appear in the serum 3 hrs later. By this time the cells in the ischemic zone have already undergone irreversible changes, and the cell membrane permeability is variably altered in the ischemic cells. At certain stages or intervals the cell membrane changes, allowing release of cytoplasmic enzymes. To correlate the changes in cell membrane permeability with the enzyme release, we used colloidal lanthanum (La+++) as a histological permeability marker in the isolated perfused hearts. The hearts removed from sprague-Dawley rats were perfused with standard Krebs-Henseleit medium gassed with 95% O2 + 5% CO2. The hypoxic medium contained mannitol instead of dextrose and was bubbled with 95% N2 + 5% CO2. The final osmolarity of the medium was 295 M osmol, pH 7. 4.

scholarly journals Chemical Characterization of Microcystis aeruginosa for Feed and Energy Uses

Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3013
Author(s):  
Larissa Souza Passos ◽  
Éryka Costa Almeida ◽  
Claudio Martin Pereira de Pereira ◽  
Alessandro Alberto Casazza ◽  
Attilio Converti ◽  
...  
Keyword(s):  
Microcystis Aeruginosa ◽  
Animal Feed ◽  
Renewable Energy Sources ◽  
Chemical Characterization ◽  
Cyanobacterial Blooms ◽  
Energy Sources ◽  
Carbohydrate Source ◽  
Heating Value ◽  
Adverse Health Effects ◽  
Degradation Reactions

Cyanobacterial blooms and strains absorb carbon dioxide, drawing attention to its use as feed for animals and renewable energy sources. However, cyanobacteria can produce toxins and have a low heating value. Herein, we studied a cyanobacterial strain harvested during a bloom event and analyzed it to use as animal feed and a source of energy supply. The thermal properties and the contents of total nitrogen, protein, carbohydrate, fatty acids, lipid, and the presence of cyanotoxins were investigated in the Microcystis aeruginosa LTPNA 01 strain and in a bloom material. Microcystins (hepatotoxins) were not detected in this strain nor in the bloom material by liquid chromatography coupled to mass spectrometry. Thermogravimetric analysis showed that degradation reactions (devolatilization) initiated at around 180 °C, dropping from approximately 90% to 20% of the samples’ mass. Our work showed that despite presenting a low heating value, both biomass and non-toxic M. aeruginosa LTPNA 01 could be used as energy sources either by burning or producing biofuels. Both can be considered a protein and carbohydrate source similar to some microalgae species as well as biomass fuel. It could also be used as additive for animal feed; however, its safety and potential adverse health effects should be further investigated.

scholarly journals Evidence of Quorum Sensing in Cyanobacteria by Homoserine Lactones: The Origin of Blooms

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1831
Author(s):  
Natalia Herrera ◽  
Fernando Echeverri
Keyword(s):  
Cell Proliferation ◽  
Quorum Sensing ◽  
Microcystis Aeruginosa ◽  
Industrial Effluents ◽  
Cyanobacterial Blooms ◽  
Cylindrospermopsis Raciborskii ◽  
Bacterial Communication ◽  
Homoserine Lactones ◽  
Exogenous Compounds ◽  
Almost All

Although several theories have been postulated to explain cyanobacterial blooms, their biochemical origin has not yet been found. In this work, we explore the existence of bacterial communication, called quorum sensing, in Microcystis aeruginosa and Cylindrospermopsis raciborskii. Thus, the application of several known acylhomoserine lactones to cultures of both cyanobacteria causes profound metabolic. At 72 h post-application, some of them produced substantial increases in cell proliferation, while others were inhibitors. There was a correlation with colony-forming activity for most of them. According to ELISA analysis, the microcystin levels were increased with some lactones. However, there was a clear difference between M. aeruginosa and C. raciborskii culture since, in the first one, there was an inducing effect on cell proliferation, while in C. raciborskii, the effects were minor. Besides, there were compound inhibitors and inducers of microcystins production in M. aeruginosa, but almost all compounds were only inducers of saxitoxin production in C. raciborskii. Moreover, each lactone appears to be involved in a specific quorum sensing process. From these results, the formation of cyanobacterial blooms in dams and reservoirs could be explained since lactones may come from cyanobacteria and other sources as bacterial microflora-associated or exogenous compounds structurally unrelated to lactones, such as drugs, industrial effluents, and agrochemicals.

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