Background:The One Health concept considers the interconnectivity,interactions and interdependence of humans,animals and the environment.Humans,animals and other organisms are constantly exposed to a wide range of nat...Background:The One Health concept considers the interconnectivity,interactions and interdependence of humans,animals and the environment.Humans,animals and other organisms are constantly exposed to a wide range of natural toxins present in the environment.Thus,there is growing concern about the potential detrimental effects that natural toxins could pose to achieve One Health.Interestingly,alkaloids,steroids and bioactive peptides obtained from natural toxins could be used for the development of therapeutic agents.Methodology:Our literature search focused on the following keywords;toxins,One Health,microbial toxins,mycotoxins,phytotoxins,phycotoxins,insect toxins and toxin effects.Google Scholar,Science Direct,PubMed and Web of Science were the search engines used to obtain primary databases.We chose relevant full-text articles and review papers published in English language only.The research was done between July 2022 and January 2023.Results:Natural toxins are poisonous substances comprising bioactive compounds produced by microorganisms,invertebrates,plants and animals.These compounds possess diverse structures and differ in biological function and toxicity,posing risks to human and animal health through the contamination of the environment,causing disease or death in certain cases.Findings from the articles reviewed revealed that effects of natural toxins on animals and humans gained more attention than the impact of natural toxins on the environment and lower organisms,irrespective of the significant roles that lower organisms play to maintain ecosystem balance.Also,systematic approaches for toxin control in the environment and utilization for beneficial purposes are inadequate in many regions.Remarkably,bioactive compounds present in natural toxins have potential for the development of therapeutic agents.These findings suggest that global,comprehensive and coordinated efforts are required for improved management of natural toxins through an interdisciplinary,One Health approach.Conclusion:Adopting a One Health approach is critical to addressing the effects of natural toxins on the health of humans,animals and the environment.展开更多
Some Pseudomonas syringae pathovars secrete tabtoxin, a monocyclic β-lactam antibiotic, responsible for chlorosis, the principal halo blight symptom in susceptible plants as oats, rye, barley, wheat and sorghum, amon...Some Pseudomonas syringae pathovars secrete tabtoxin, a monocyclic β-lactam antibiotic, responsible for chlorosis, the principal halo blight symptom in susceptible plants as oats, rye, barley, wheat and sorghum, among other. Here, we demonstrated that the production of tabtoxin in a P. syringae strain increased at least 150%, when choline, betaine or dimethylglycine were used as nitrogen source, or when choline was added as osmoprotectant in hyperosmolar culture media. Besides, we investigated the induction of phosphorylcholine phosphatase (PchP) activity when choline or its metabolites were used as nitrogen sources. PchP is an enzyme involved in Pseudomonas aeruginosa pathogenesis through its contribution to the breakdown of choline-containing compounds of the host cells. Considering these results and that the success of a pathogenic microorganism depends on its ability to survive and proliferate in its target tissue, we propose that choline is one of the plant signals that contribute to establishment of the infection by tabtoxin-producing strains of P. syringae.展开更多
Microbes are good sources of biologically active compounds that can be used as pharmaceuticals and agrochemicals. As part of our continuous efforts in search for biopesticides from natural sources, a fungus is isolate...Microbes are good sources of biologically active compounds that can be used as pharmaceuticals and agrochemicals. As part of our continuous efforts in search for biopesticides from natural sources, a fungus is isolated from leaves of Pandanus amaryllifolius that shows severe necrosis. This fungus is cultured in potato dextrose agar and identified as Curvularia intermedia. The ethyl acetate extract of the liquid culture medium is phytotoxic. Identification and bioassay of αβ-dehydrocurvularin (1) and curvularin (2) from this fungus are described. Monoacetyldehydrocurvularin (3), and diacetyldehydrocurvularin (4) are synthesized from 1. Phytoxicity rankings in a variety of bioassays are 1 > 2 > 4 > 3.展开更多
Exserohilum monoceras （Drechsler） Leonard and Suggs is a potential biocontrol agent for the control of Echinochloa species. This fungus causes leaf blight in Echinochloa species, but does not damage rice. Phytotoxic...Exserohilum monoceras （Drechsler） Leonard and Suggs is a potential biocontrol agent for the control of Echinochloa species. This fungus causes leaf blight in Echinochloa species, but does not damage rice. Phytotoxicity of the fungal fermented broth was evaluated through the bioassay and the active ingredients were preliminarily isolated by using silica gel column chromatography （CC） in this study. The most active fraction 5-Ⅲ was obtained and analyzed by gas chromatography-mass spectrometry （GC-MS）. The results show that 5-Ⅲ consisted of many compounds, in which 36 compounds accounted for 94.24% of total peak area. Di-n-butyl phthalate （DBP） displayed the highest activity accounted for 9.24% of the total peak area, suggesting that DBP may be one of the main active compounds produced by E. monoceras.展开更多
A phytotoxin from Xanthomonas campestris pv. retroflexus was isolated using a chromatographer and HPLC, and the components were identified to be a mixture of minor molecular compounds including organic acids and cyclo...A phytotoxin from Xanthomonas campestris pv. retroflexus was isolated using a chromatographer and HPLC, and the components were identified to be a mixture of minor molecular compounds including organic acids and cyclo-（proline-phenylalanine）. The greenhouse cultivation test was used to determine the influence of the isolated fractions on the growth of target weed redroot pigweed （Amaranthus retroflexus L）. The experimental results demonstrated that the cyclo-（Pro-Phe） had the weed inhibit activity obviously on dicotyledonous weed and the mixture with six organic acids showed stronger bioactivity. Further, greenhouse and field test were processed, and the test showed that the use of the toxin appeared to have the potential to be developed further as a bioherbicide system to control weedy grasses.展开更多
Hairy vetch (Vicia villosa Roth.) has been recognized as a good candidate for weed suppressive mulch in organic no-till cropping systems. In our study, the allelopathic potential of hairy vetch, fall rye (Secale cerea...Hairy vetch (Vicia villosa Roth.) has been recognized as a good candidate for weed suppressive mulch in organic no-till cropping systems. In our study, the allelopathic potential of hairy vetch, fall rye (Secale cereale L.) and winter wheat (Triticum aestivum L.) (extracted species) were evaluated at both vegetative and reproductive developmental stages (extract stage) based on the germination and radicle elongation of five response species using aqueous extracts in soil microcosms. Our study found hairy vetch shoot extract to have little allelopathic potential compared to fall rye or winter wheat, both species for which the allelopathic potential is well documented. Interestingly, hairy vetch was the only extracted species to increase in allelopathic suppression of radicle elongation at the reproductive stage when plant biomass is near maximum. This result was conceivably due to the increased concentration of the putative allelochemical cyanamide in reproductive tissue. Chemical inhibition of radicle elongation in this extract, however, was only observed in the domesticated response species wheat (Triticum aestivum L.) and canola (Brassica napus L.). The allelopathic effect on germination varied and depended on extracted species, extract stage, and response species;whereas the effect on radicle elongation was similar among extracted species, yet unique within response species. This research demonstrated that allelopathy studies should include multiple allelopathic and response species to accurately quantify the magnitude of chemical effects among allelopathic species and to rule out potential phytotoxic chemical defense/detoxification mechanisms that exist in some response species.展开更多
The genus Phaeoacremonium is associated die-back of various woody hosts. In this study, Phaeoaeremonium specie was isolated from necrotic woody tissue of Platanus occidentalies L. （Platanus）. Morphological and cultu...The genus Phaeoacremonium is associated die-back of various woody hosts. In this study, Phaeoaeremonium specie was isolated from necrotic woody tissue of Platanus occidentalies L. （Platanus）. Morphological and cultural characteristics were used to identify the species, which known, and being described as Phaeoacremonium aleophillum. This is the first report on identifying Phaeoacremonium aleophillum from Platanus in Iraq, previously reports accommodate Cephalosporium acremonium from Platanus trees. This specie is able to produce toxic metabolites. Applications of P. aleophillum crude and cell-free filtrates induced severe chlorosis and necrosis on Platanus leaves after 24 hours of treatment with P. aleophillum culture filtrate. A novel phytotoxin was isolated from P. aleophillurn and culture filtrate was identified as galactouronic acid.展开更多
基金supported by The Africa Education Initiative(NEF),USA and the National Veterinary Research Institute Vom,Nigeria.
文摘Background:The One Health concept considers the interconnectivity,interactions and interdependence of humans,animals and the environment.Humans,animals and other organisms are constantly exposed to a wide range of natural toxins present in the environment.Thus,there is growing concern about the potential detrimental effects that natural toxins could pose to achieve One Health.Interestingly,alkaloids,steroids and bioactive peptides obtained from natural toxins could be used for the development of therapeutic agents.Methodology:Our literature search focused on the following keywords;toxins,One Health,microbial toxins,mycotoxins,phytotoxins,phycotoxins,insect toxins and toxin effects.Google Scholar,Science Direct,PubMed and Web of Science were the search engines used to obtain primary databases.We chose relevant full-text articles and review papers published in English language only.The research was done between July 2022 and January 2023.Results:Natural toxins are poisonous substances comprising bioactive compounds produced by microorganisms,invertebrates,plants and animals.These compounds possess diverse structures and differ in biological function and toxicity,posing risks to human and animal health through the contamination of the environment,causing disease or death in certain cases.Findings from the articles reviewed revealed that effects of natural toxins on animals and humans gained more attention than the impact of natural toxins on the environment and lower organisms,irrespective of the significant roles that lower organisms play to maintain ecosystem balance.Also,systematic approaches for toxin control in the environment and utilization for beneficial purposes are inadequate in many regions.Remarkably,bioactive compounds present in natural toxins have potential for the development of therapeutic agents.These findings suggest that global,comprehensive and coordinated efforts are required for improved management of natural toxins through an interdisciplinary,One Health approach.Conclusion:Adopting a One Health approach is critical to addressing the effects of natural toxins on the health of humans,animals and the environment.
文摘Some Pseudomonas syringae pathovars secrete tabtoxin, a monocyclic β-lactam antibiotic, responsible for chlorosis, the principal halo blight symptom in susceptible plants as oats, rye, barley, wheat and sorghum, among other. Here, we demonstrated that the production of tabtoxin in a P. syringae strain increased at least 150%, when choline, betaine or dimethylglycine were used as nitrogen source, or when choline was added as osmoprotectant in hyperosmolar culture media. Besides, we investigated the induction of phosphorylcholine phosphatase (PchP) activity when choline or its metabolites were used as nitrogen sources. PchP is an enzyme involved in Pseudomonas aeruginosa pathogenesis through its contribution to the breakdown of choline-containing compounds of the host cells. Considering these results and that the success of a pathogenic microorganism depends on its ability to survive and proliferate in its target tissue, we propose that choline is one of the plant signals that contribute to establishment of the infection by tabtoxin-producing strains of P. syringae.
文摘Microbes are good sources of biologically active compounds that can be used as pharmaceuticals and agrochemicals. As part of our continuous efforts in search for biopesticides from natural sources, a fungus is isolated from leaves of Pandanus amaryllifolius that shows severe necrosis. This fungus is cultured in potato dextrose agar and identified as Curvularia intermedia. The ethyl acetate extract of the liquid culture medium is phytotoxic. Identification and bioassay of αβ-dehydrocurvularin (1) and curvularin (2) from this fungus are described. Monoacetyldehydrocurvularin (3), and diacetyldehydrocurvularin (4) are synthesized from 1. Phytoxicity rankings in a variety of bioassays are 1 > 2 > 4 > 3.
基金the National Natural Science Foundation of China(30671381,30671381)Guangdong Provincial Natural Science Foundation of China(06300411)for the financial supports
文摘Exserohilum monoceras （Drechsler） Leonard and Suggs is a potential biocontrol agent for the control of Echinochloa species. This fungus causes leaf blight in Echinochloa species, but does not damage rice. Phytotoxicity of the fungal fermented broth was evaluated through the bioassay and the active ingredients were preliminarily isolated by using silica gel column chromatography （CC） in this study. The most active fraction 5-Ⅲ was obtained and analyzed by gas chromatography-mass spectrometry （GC-MS）. The results show that 5-Ⅲ consisted of many compounds, in which 36 compounds accounted for 94.24% of total peak area. Di-n-butyl phthalate （DBP） displayed the highest activity accounted for 9.24% of the total peak area, suggesting that DBP may be one of the main active compounds produced by E. monoceras.
基金Supported by the National Natural Science Fotmdation of China （No.30370939）, Natural Science Foundation of Zhejiang Province （No.300054） and Science Research Plan of Zhejiang Province （No.2004C22005）.
文摘A phytotoxin from Xanthomonas campestris pv. retroflexus was isolated using a chromatographer and HPLC, and the components were identified to be a mixture of minor molecular compounds including organic acids and cyclo-（proline-phenylalanine）. The greenhouse cultivation test was used to determine the influence of the isolated fractions on the growth of target weed redroot pigweed （Amaranthus retroflexus L）. The experimental results demonstrated that the cyclo-（Pro-Phe） had the weed inhibit activity obviously on dicotyledonous weed and the mixture with six organic acids showed stronger bioactivity. Further, greenhouse and field test were processed, and the test showed that the use of the toxin appeared to have the potential to be developed further as a bioherbicide system to control weedy grasses.
文摘Hairy vetch (Vicia villosa Roth.) has been recognized as a good candidate for weed suppressive mulch in organic no-till cropping systems. In our study, the allelopathic potential of hairy vetch, fall rye (Secale cereale L.) and winter wheat (Triticum aestivum L.) (extracted species) were evaluated at both vegetative and reproductive developmental stages (extract stage) based on the germination and radicle elongation of five response species using aqueous extracts in soil microcosms. Our study found hairy vetch shoot extract to have little allelopathic potential compared to fall rye or winter wheat, both species for which the allelopathic potential is well documented. Interestingly, hairy vetch was the only extracted species to increase in allelopathic suppression of radicle elongation at the reproductive stage when plant biomass is near maximum. This result was conceivably due to the increased concentration of the putative allelochemical cyanamide in reproductive tissue. Chemical inhibition of radicle elongation in this extract, however, was only observed in the domesticated response species wheat (Triticum aestivum L.) and canola (Brassica napus L.). The allelopathic effect on germination varied and depended on extracted species, extract stage, and response species;whereas the effect on radicle elongation was similar among extracted species, yet unique within response species. This research demonstrated that allelopathy studies should include multiple allelopathic and response species to accurately quantify the magnitude of chemical effects among allelopathic species and to rule out potential phytotoxic chemical defense/detoxification mechanisms that exist in some response species.
文摘The genus Phaeoacremonium is associated die-back of various woody hosts. In this study, Phaeoaeremonium specie was isolated from necrotic woody tissue of Platanus occidentalies L. （Platanus）. Morphological and cultural characteristics were used to identify the species, which known, and being described as Phaeoacremonium aleophillum. This is the first report on identifying Phaeoacremonium aleophillum from Platanus in Iraq, previously reports accommodate Cephalosporium acremonium from Platanus trees. This specie is able to produce toxic metabolites. Applications of P. aleophillum crude and cell-free filtrates induced severe chlorosis and necrosis on Platanus leaves after 24 hours of treatment with P. aleophillum culture filtrate. A novel phytotoxin was isolated from P. aleophillurn and culture filtrate was identified as galactouronic acid.
