Toxic harmful algal blooms(HABs)can cause deleterious effects in marine organisms,threatening the stability of marine ecosystems.It is well known that different strains,natural populations and growth conditions of the...Toxic harmful algal blooms(HABs)can cause deleterious effects in marine organisms,threatening the stability of marine ecosystems.It is well known that different strains,natural populations and growth conditions of the same toxic algal species may lead to different amount of phycotoxin production and the ensuing toxicity.To fully assess the ecological risk of toxic HABs,it is of great importance to investigate the toxic effects of phycotoxins in marine organisms.In this study,the short-term toxicity of 14 common phycotoxins(alone and in combination)in the marine zooplankton Artemia salina was investigated.The 48 h LC_(50)of the 14 phycotoxins varied from 0.0193µg/mL to 2.415µg/mL.The most potent phycotoxin was azaspiracids-3(AZA3;with a LC_(50)of 0.0193µg/mL),followed by azaspiracids-2(AZA2;0.0226µg/mL),pectenotoxin-2(PTX2;0.0460µg/mL)and dinophysistoxin-1(DTX1;0.0818µg/mL).For the binary exposure,okadaic acid(OA)induced potential additive effects with DTX1,probably due to their similar structure(polyether fatty acid)and mode of action(attacking the serine/threonine phosphoprotein phosphatases).On the other hand,OA showed potential antagonistic effects with PTX2,which might be accounted for by their activation on the detoxification activity of cytochrome P450 activity.In addition,DTX1 induced potential synergetic effects with saxitoxin(STX),yessotoxin(YTX)or PTX2,suggesting the hazard potency of the mixtures of DTX1 and other phycotoxins(like STX,YTX and PTX2)with regard to the ecological risk.These results provide valuable toxicological data for assessing the impact of phycotoxins on marine planktonic species and highlight the potential ecological risk of toxic HABs in marine ecosystems.展开更多
Adventitious root(AR)formation is a unique feature of plant reproduction and plays a vital role in crop production as many horticultural and forestry plants are propagated through cuttings.A growing number of reports ...Adventitious root(AR)formation is a unique feature of plant reproduction and plays a vital role in crop production as many horticultural and forestry plants are propagated through cuttings.A growing number of reports have shown that microbes,particularly mycorrhizal fungi are able to promote AR formation,but the underlying mechanisms remain largely unclear.This study established an in vitro culture system and investigated AR formation in microcuttings of Rhododendron fortunei Lindl.inoculated with Oidiodendron maius Barron Om19,an ericoid mycorrhizal fungus strain.Hormones and precursors involved in the biosynthesis of indole-3-acetic acid(IAA)in Om19 mycelium were analyzed.Om19 was able to produce a large quantity of tryptophan(Trp)and also indole-3-pyruvate(IPA)and IAA,indicating that IAA biosynthesis in Om19 could be through a Trp-dependent pathway.After inoculation of Om19,ARs were quickly formed in microcuttings.Symbiosis related genes were activated in ARs,and Om19 effectively colonized the roots.YUC3,a key gene in plant biosynthesis of IAA and genes involved in nitrogen(N)uptake and metabolism,phosphorus(P)uptake were highly upregulated.Plants absorbed significantly greater quantity of mineral nutrients,and their growth was substantially enhanced compared to the control plants without Om19 inoculation.A working model for Om19 enhanced AR formation was proposed.The rapid formation of ARs in cuttings could be due in part to the induction of IAA biosynthesized by Om19 and also attributed to Trp catalyzed biosynthesis of IAA in plants.AR formation,in turn,provided Om19 preferred sites for colonization.Our study suggested that in addition to promoting AR formation,Om19 could potentially be used as a new biofertilizer for enhancing production of ericaceous plants,such as blueberry,cranberry,and rhododendron.展开更多
Parent and alkylated polycyclic aromatic hydrocarbons(alkyl-PAHs),which are a class of important toxic components of crude oil especially in the marine environment,exhibit adverse effects on aquatic life and potential...Parent and alkylated polycyclic aromatic hydrocarbons(alkyl-PAHs),which are a class of important toxic components of crude oil especially in the marine environment,exhibit adverse effects on aquatic life and potentially pose a human health risk.However,the lack of chronic toxicity data is one of the hindrances for alkylPAHs when assessing their ecological risks.In this study,predicted no-effect concentrations(PNECs)in seawater and marine sediment for ten parent-and alkyl-PAHs were derived by applying species sensitivity distributions(SSDs)and quantitative structure-activity relationships(QSARs).The local area,Dalian Bay,where an oil-spilled accident happened in 2010,was chosen as a case site to assess ecological risks for ten PAHs in surface seawaters and marine sediments.Their PNECs in seawater and sediment for protecting aquatic organisms in marine ecosystems were calculated and recommended in the range of 0.012-2.79μg/L and 48.2-1337 ng/g(dry weight),respectively.Overall,the derived PNECs for the studied PAHs in seawater and marine sediment were comparable to those obtained by classical methods.Risk quotient results indicate low ecological risks to ecosystems for ten parent-and alkyl-PAHs in surface seawaters and surface sediments from the Dalian Bay.These findings provide a first insight into the PNECs and ecological risks of alkyl-PAHs,emphasizing the role of the computational toxicology in ecological risk assessments.The use of QSARs has been identified as a valuable tool for preliminarily assessing ecological risks of emerging pollutants,being more predictable of real exposure scenarios for risk assessment purposes.展开更多
In recent years,pollution caused by the discharge of industrial wastewater into Bohai Bay has posed a potential threat to the health of surrounding residents.Sludge was collected from the outlet of a factory that disc...In recent years,pollution caused by the discharge of industrial wastewater into Bohai Bay has posed a potential threat to the health of surrounding residents.Sludge was collected from the outlet of a factory that discharges effluent into Bohai Bay,and alcohol extracts of sludge(SE)were prepared.We confirmed by UPLC-MS/MS analysis that the SE contained PAHs,including fluorene,pyrene,and phenanthrene.Zebrafish embryos as animal models were exposed to 0.1,0.3,0.5,1 and 5 mg/mL SE from 2 to 4 h post-fertilization(hpf)until 120 hpf.The results showed that SE caused a concentration-dependent increase in mortality and a decrease in hatchability.We found that SE significantly reduced eye pigmentation and decreased the movement of embryos and larvae.In addition,SE decreased triiodothyronine(T3)content and down-regulated the mRNA expression of some thyroid hormone-related genes including TPO and Thrβ,and caused the up-regulation of Dio2 and Dio3 at 120 hpf.Exposure to three individual PAHs found in SE,namely fluorene,pyrene,and phenanthrene,caused morphological and transcriptional changes that were similar to those caused by SE exposure.These findings indicate that PAHs in SE can reduce the pigmentation of zebrafish,which may be related to the genetic changes associated with thyroid hormones,and that zebrafish eye pigmentation can be used as an indicator of PAHs exposure.展开更多
基金The National Natural Science Foundation of China under contract No.41576120the Special Fund Project for Marine and Fishery Protection and Development in Fujian Province,China under contract No.FZJZ-2021-1the National Key R&D Program of China under contract No.2017YFC1404803.
文摘Toxic harmful algal blooms(HABs)can cause deleterious effects in marine organisms,threatening the stability of marine ecosystems.It is well known that different strains,natural populations and growth conditions of the same toxic algal species may lead to different amount of phycotoxin production and the ensuing toxicity.To fully assess the ecological risk of toxic HABs,it is of great importance to investigate the toxic effects of phycotoxins in marine organisms.In this study,the short-term toxicity of 14 common phycotoxins(alone and in combination)in the marine zooplankton Artemia salina was investigated.The 48 h LC_(50)of the 14 phycotoxins varied from 0.0193µg/mL to 2.415µg/mL.The most potent phycotoxin was azaspiracids-3(AZA3;with a LC_(50)of 0.0193µg/mL),followed by azaspiracids-2(AZA2;0.0226µg/mL),pectenotoxin-2(PTX2;0.0460µg/mL)and dinophysistoxin-1(DTX1;0.0818µg/mL).For the binary exposure,okadaic acid(OA)induced potential additive effects with DTX1,probably due to their similar structure(polyether fatty acid)and mode of action(attacking the serine/threonine phosphoprotein phosphatases).On the other hand,OA showed potential antagonistic effects with PTX2,which might be accounted for by their activation on the detoxification activity of cytochrome P450 activity.In addition,DTX1 induced potential synergetic effects with saxitoxin(STX),yessotoxin(YTX)or PTX2,suggesting the hazard potency of the mixtures of DTX1 and other phycotoxins(like STX,YTX and PTX2)with regard to the ecological risk.These results provide valuable toxicological data for assessing the impact of phycotoxins on marine planktonic species and highlight the potential ecological risk of toxic HABs in marine ecosystems.
基金supported by National Nature Science Foundation of China(Grant No.31801897)to X.W.Scientific Research Foundation of Graduate School at the Fujian Agriculture and Forestry University(324-1122YB026)to X.W.Science and Technology Commission of Shanghai Municipality(Grant No.18DZ2283500)to C.Z.
文摘Adventitious root(AR)formation is a unique feature of plant reproduction and plays a vital role in crop production as many horticultural and forestry plants are propagated through cuttings.A growing number of reports have shown that microbes,particularly mycorrhizal fungi are able to promote AR formation,but the underlying mechanisms remain largely unclear.This study established an in vitro culture system and investigated AR formation in microcuttings of Rhododendron fortunei Lindl.inoculated with Oidiodendron maius Barron Om19,an ericoid mycorrhizal fungus strain.Hormones and precursors involved in the biosynthesis of indole-3-acetic acid(IAA)in Om19 mycelium were analyzed.Om19 was able to produce a large quantity of tryptophan(Trp)and also indole-3-pyruvate(IPA)and IAA,indicating that IAA biosynthesis in Om19 could be through a Trp-dependent pathway.After inoculation of Om19,ARs were quickly formed in microcuttings.Symbiosis related genes were activated in ARs,and Om19 effectively colonized the roots.YUC3,a key gene in plant biosynthesis of IAA and genes involved in nitrogen(N)uptake and metabolism,phosphorus(P)uptake were highly upregulated.Plants absorbed significantly greater quantity of mineral nutrients,and their growth was substantially enhanced compared to the control plants without Om19 inoculation.A working model for Om19 enhanced AR formation was proposed.The rapid formation of ARs in cuttings could be due in part to the induction of IAA biosynthesized by Om19 and also attributed to Trp catalyzed biosynthesis of IAA in plants.AR formation,in turn,provided Om19 preferred sites for colonization.Our study suggested that in addition to promoting AR formation,Om19 could potentially be used as a new biofertilizer for enhancing production of ericaceous plants,such as blueberry,cranberry,and rhododendron.
基金The National Key Research and Development Program of China under contract No.2016YFC1402305the Postdoctoral Research Foundation of China under contract No.2016M601148the Scientific Research Special Fund of Marine Public Welfare Industry under contract No.201305002
文摘Parent and alkylated polycyclic aromatic hydrocarbons(alkyl-PAHs),which are a class of important toxic components of crude oil especially in the marine environment,exhibit adverse effects on aquatic life and potentially pose a human health risk.However,the lack of chronic toxicity data is one of the hindrances for alkylPAHs when assessing their ecological risks.In this study,predicted no-effect concentrations(PNECs)in seawater and marine sediment for ten parent-and alkyl-PAHs were derived by applying species sensitivity distributions(SSDs)and quantitative structure-activity relationships(QSARs).The local area,Dalian Bay,where an oil-spilled accident happened in 2010,was chosen as a case site to assess ecological risks for ten PAHs in surface seawaters and marine sediments.Their PNECs in seawater and sediment for protecting aquatic organisms in marine ecosystems were calculated and recommended in the range of 0.012-2.79μg/L and 48.2-1337 ng/g(dry weight),respectively.Overall,the derived PNECs for the studied PAHs in seawater and marine sediment were comparable to those obtained by classical methods.Risk quotient results indicate low ecological risks to ecosystems for ten parent-and alkyl-PAHs in surface seawaters and surface sediments from the Dalian Bay.These findings provide a first insight into the PNECs and ecological risks of alkyl-PAHs,emphasizing the role of the computational toxicology in ecological risk assessments.The use of QSARs has been identified as a valuable tool for preliminarily assessing ecological risks of emerging pollutants,being more predictable of real exposure scenarios for risk assessment purposes.
基金funded by the National Natural Science Foundation of China(82060672)the Program for Interdisciplinary Innovation team in Inner Mongolia Minzu University,China(Dongwu-2023)the Natural Science Foundation of Inner Mongolia Autonomous Region of China(2020MS08103).
文摘In recent years,pollution caused by the discharge of industrial wastewater into Bohai Bay has posed a potential threat to the health of surrounding residents.Sludge was collected from the outlet of a factory that discharges effluent into Bohai Bay,and alcohol extracts of sludge(SE)were prepared.We confirmed by UPLC-MS/MS analysis that the SE contained PAHs,including fluorene,pyrene,and phenanthrene.Zebrafish embryos as animal models were exposed to 0.1,0.3,0.5,1 and 5 mg/mL SE from 2 to 4 h post-fertilization(hpf)until 120 hpf.The results showed that SE caused a concentration-dependent increase in mortality and a decrease in hatchability.We found that SE significantly reduced eye pigmentation and decreased the movement of embryos and larvae.In addition,SE decreased triiodothyronine(T3)content and down-regulated the mRNA expression of some thyroid hormone-related genes including TPO and Thrβ,and caused the up-regulation of Dio2 and Dio3 at 120 hpf.Exposure to three individual PAHs found in SE,namely fluorene,pyrene,and phenanthrene,caused morphological and transcriptional changes that were similar to those caused by SE exposure.These findings indicate that PAHs in SE can reduce the pigmentation of zebrafish,which may be related to the genetic changes associated with thyroid hormones,and that zebrafish eye pigmentation can be used as an indicator of PAHs exposure.
