The possible application of magnesium(Mg)in glaucoma surgical treatment has been investigated in our previous work.In this paper,the degradation behavior and biocompatibility of Mg coated with hydroxyapatite(HA)and di...The possible application of magnesium(Mg)in glaucoma surgical treatment has been investigated in our previous work.In this paper,the degradation behavior and biocompatibility of Mg coated with hydroxyapatite(HA)and dicalcium phosphate dihydrate(DCPD)in eye environment were evaluated,and uncoated Mg was used for comparison.It was found that uniform corrosion occurred macroscopically to the coated Mg samples in sodium lactate ringer’s injection(SLRI)as well as in the rabbit eyes.In micro-scale,the corrosion was characterized by local cracking and pitting primarily.Mg and calcium(Ca)were incorporated into the surface corrosion products and a multi-layer structure was formed.Compared to other samples,HA-coated Mg slowed down dramatically the alkalinity of the solution and the ion release of the sample,and exhibited the lowest corrosion rate in SLRI,which was about 0.22 mm/a.In terms of biocompatibility,fibroblasts demonstrated high viability in the HA-coated and DCPD-coated Mg groups(p<0.05)in vitro.In vivo,HA-coated Mg was found to show lower inflammatory response and fibrosis than the other groups did,as indicated by hematoxylin-eosin and immunofluorescence staining.During the degrading process of HA-coated Mg in the rabbits’eyes,no inflammation was found in the anterior chamber,lens,and vitreous body.HA-coated Mg was fully biodegraded fifteen weeks post-operation,and the scleral drainage channel(SDC)was formed without obvious scarring.It is concluded that HA-coated Mg implantation is a promising adjunctive procedure to improve the success rate of trabeculectomy.Statement of significance:Magnesium(Mg)has shown to be a potential biomaterial for ophthalmic implants in our previous work.However,inflammatory response resulted from the low corrosion resistance of Mg is a major concern.It is shown here that Mg coated with different calcium phosphates can improve these properties in varying degrees and keep the scleral drainage channel unobstructed and unscarred.Based on our in vitro and in vivo studies,HA-coated Mg exhibited a better degradation behavior and excellent biocompatibility.The scleral drainage channel still exists and aqueous humor flows out smoothly after the full degradation of the implant.It is concluded that HA-coated Mg is a promising biomaterial to increase the therapeutic efficiency of trabeculectomy for glaucoma.展开更多
Insects have become an efficient and eco-friendly bioreactor for plastics and even micro/nano-plastics biodegradation.However,the optimal conditions for rearing insects to maximize plastic biodegradation and the under...Insects have become an efficient and eco-friendly bioreactor for plastics and even micro/nano-plastics biodegradation.However,the optimal conditions for rearing insects to maximize plastic biodegradation and the underlying mechanisms remain unclear,hindering its practical applications.We investigated the effects of multiple rearing factors on plastics degradation efficiency of Tenebrio molitor larvae,including larval instar,water addition frequency,plastic specific surface area and plastic types.The functional gut microbes and enzymes associated with the improved efficiency were further explored.Our findings revealed that adult larvae achieved the highest plastics degradation efficiency when receiving regular water additions without causing drowning of insects on hydrophobic plastics.Additionally,they effectively ingested foam plastics of polystyrene,polyethylene and polyurethane without prior comminution and densification.The biodegradation processes involving oxidation,cleavage and depolymerization of plastics were all demonstrated.Furthermore,foam plastic type-dependent functional microbes and enzymes that contributed to the efficient plastic degradationwere identified.Thiswork provides valuable insights into the practical applications of insects for sustainable plastics biodegradation.展开更多
Cresyl diphenyl phosphate(CDP),an emerging aryl organophosphate ester(OPE),exhibits potential toxic effects and is frequently found in diverse environmental media,thereby raising concerns about environmental pollution...Cresyl diphenyl phosphate(CDP),an emerging aryl organophosphate ester(OPE),exhibits potential toxic effects and is frequently found in diverse environmental media,thereby raising concerns about environmental pollution.Biodegradation demonstrates substantial potential for CDP removal from the environment.This study investigated the biodegradation mechanisms of CDP using anaerobic activated sludge(AnAS).The biodegradation of 1-mg/L CDP followed a first-order kinetic model with a degradation kinetic constant of 0.943 d^(-1),and the addition of different electron acceptors affected the degradation rate.High-resolution mass spectrometry identified seven transformation products(TPs)of CDP.The pathways of CDP degradation in anaerobic conditions were proposed,with carboxylation products being the most dominant intermediate products.The structure of the anaerobic microbial community at different degradation time points in CDP-amended microcosms was examined.The linear discriminant analysis(LDA)of effect size(LEfSe)potentially underscored the pivotal role of Methyloversatilis in CDP biodegradation.Zebrafish embryotoxicity experiments revealed both lethal and morphogenetic impacts of CDP on zebrafish embryos.The survival rate,hatching rate,and body length indicators of zebrafish embryos underscored the detoxification of CDP and its resultant intermediates by AnAS.This study offers new insights into the fate and biodegradation mechanisms of CDP in wastewater treatment plants.展开更多
Bioremediation has gained significant attention due to its potential to remove azo dyes.However,the challenges microor-ganisms face in surviving when azo dyes are the sole carbon source limit its widespread applicatio...Bioremediation has gained significant attention due to its potential to remove azo dyes.However,the challenges microor-ganisms face in surviving when azo dyes are the sole carbon source limit its widespread application.This study aimed to improve the biodegradation of azo dyes by utilizing Baijiu distiller’s grains leachate(BDGL)as a co-substrate.The experimental results demon-strated that BDGL significantly enhanced Providencia rettgeri’s ability to degrade the model pollutant Acid Black 210(AB210),achieving a decolorization efficiency of 94.5%.This may be attributed to the nutrient-rich composition of BDGL,which includes ethanol and protein,providing a favorable substrate for bacterial growth and activity.The higher biomass and increased activities of azoreductase and quinone oxidoreductase in the BDGL group further supported these findings.Additionally,this method demonstra-ted broad-spectrum degradation of azo dyes(Direct Red 5B,Acid Red 73,and Congo Red)with different structures,highlighting its potential applicability.Metabolite assays combined with transcriptomics analyses revealed that the expression of functional genes re-lated to redox reactions,azo bond cleavage,and hydrolysis increased under the co-metabolic conditions of BDGL,resulting in stronger reducing power that further mineralized the dye into smaller metabolites.Our study offers a practical strategy for the simulta-neous treatment of dye-containing wastewater and Baijiu distiller’s grains,with significant environmental and industrial applications.展开更多
The selection of carbon sources and the biosynthesis of polyhydroxybutyrate(PHB)by the Azotobacter vinelandii N-15 strain using renewable raw materials were investigated.Among the tested substrates(starch,sucrose,mola...The selection of carbon sources and the biosynthesis of polyhydroxybutyrate(PHB)by the Azotobacter vinelandii N-15 strain using renewable raw materials were investigated.Among the tested substrates(starch,sucrose,molasses,bran),molasses as the carbon source yielded the highest PHB production.The maximum polymer yield(26%of dry biomass)was achieved at a molasses concentration of 40 g/L.PHB formation was confirmed via thinlayer chromatography,gas chromatography and Fourier transform infrared spectroscopy.Composite films based on PHB,polylactic acid(PLA),and their blends were fabricated using the solvent casting.The biodegradation of these films was studied with bacteria isolated from plastic-contaminated soil.These bacteria utilized the biopolymers as their sole carbon source,with the biodegradation process lasting three months.Structural and chemical changes in the films were analyzed using FTIR spectroscopy,differential scanning calorimetry,and thermogravimetry.Among the microorganisms used to study the biodegradation of PHB,PLA,and their blends,Streptomyces sp.K2 and Streptomyces sp.K4 exhibited the highest biodegradation efficiency.PHB-containing films demonstrated significant advantages over other biodegradable polymers,as they degrade under aerobic conditions via enzymatic hydrolysis using microbial depolymerases.展开更多
Bioremediation of organophosphorus pesticides in contaminated foodstuffs using probiotics has been increasingly under the spotlight in recent years,though the biodegradation mechanism and derived intermediate products...Bioremediation of organophosphorus pesticides in contaminated foodstuffs using probiotics has been increasingly under the spotlight in recent years,though the biodegradation mechanism and derived intermediate products remain unclear.This study aimed to help fill this knowledge gap and examined the degradation mechanism of organophosphorus pesticide,chlorpyrifos,in milk by Lactobacillus delbrueckii ssp.bulgaricus using gas chromatography-tandem mass spectrometry(GC-MS/MS)combined with transcriptome analysis.After the strain was cultured for 20 h in the presence of chlorpyrifos,differential expressions of 383 genes were detected,including genes probably implicated during chlorpyrifos degradation such as those related to hydrolase,phosphoesterase,diphosphatase,oxidoreductase,dehydratase,as well as membrane transporters.GC-MS/MS analysis revealed the changes of secondary metabolites in L.bulgaricus during milk fermentation due to chlorpyrifos stress.6-Methylhexahydro-2H-azepin-2-one,2,6-dihydroxypyridine and methyl 2-aminooxy-4-methylpentanoate as intermediates,along with the proposed pathways,might be involved in chlorpyrifos biodegradation by L.bulgaricus.展开更多
The Arctic,an essential ecosystem on Earth,is subject to pronounced anthropogenic pressures,most notable being the climate change and risks of crude oil pollution.As crucial elements of Arctic environments,benthic mic...The Arctic,an essential ecosystem on Earth,is subject to pronounced anthropogenic pressures,most notable being the climate change and risks of crude oil pollution.As crucial elements of Arctic environments,benthic microbiomes are involved in climate-relevant biogeochemical cycles and hold the potential to remediate upcoming contamination.Yet,the Arctic benthic microbiomes are among the least explored biomes on the planet.Here we combined geochemical analyses,incubation experiments,and microbial community profiling to detail the biogeography and biodegradation potential of Arctic sedimentary microbiomes in the northern Barents Sea.The results revealed a predominance of bacterial and archaea phyla typically found in the deep marine biosphere,such as Chloroflexi,Atribacteria,and Bathyarcheaota.The topmost benthic communities were spatially structured by sedimentary organic carbon,lacking a clear distinction among geographic regions.With increasing sediment depth,the community structure exhibited stratigraphic variability that could be correlated to redox geochemistry of sediments.The benthic microbiomes harbored multiple taxa capable of oxidizing hydrocarbons using aerobic and anaerobic pathways.Incubation of surface sediments with crude oil led to proliferation of several genera from the so-called rare biosphere.These include Alkalimarinus and Halioglobus,previously unrecognized as hydrocarbon-degrading genera,both harboring the full genetic potential for aerobic alkane oxidation.These findings increase our understanding of the taxonomic inventory and functional potential of unstudied benthic microbiomes in the Arctic.展开更多
The degradation of tilmicosin(TLM),a semi-synthetic 16-membered macrolide antibiotic,has been receiving increasing attention.Conventionally,there are three tilmicosin degradation methods,and among them microbial degra...The degradation of tilmicosin(TLM),a semi-synthetic 16-membered macrolide antibiotic,has been receiving increasing attention.Conventionally,there are three tilmicosin degradation methods,and among them microbial degradation is considered the best due to its high efficiency,eco-friendliness,and low cost.Coincidently,we found a new strain,Glutamicibacter nicotianae sp.AT6,capable of degrading high-concentration TLM at 100 mg/L with a 97%removal efficiency.The role of tryptone was as well investigated,and the results revealed that the loading of tryptone had a significant influence on TLM removals.The toxicity assessment indicated that strain AT6 could efficiently convert TLM into less-toxic substances.Based on the identified intermediates,the degradation of TLM by AT6 processing through two distinct pathways was then proposed.展开更多
The sensitivity of biodegradation on diamondoids was investigated using a series of biodegraded oil samples from the Ronier tectonic unit of Bongor Basin,Chad.The results suggest that diamondoids,including adamantanes...The sensitivity of biodegradation on diamondoids was investigated using a series of biodegraded oil samples from the Ronier tectonic unit of Bongor Basin,Chad.The results suggest that diamondoids,including adamantanes(As)and diamantanes(Ds),are relatively resistant to biodegradation and obvious biodegradation was observed in oils with a Peters-Moldowan(PM)biodegradation rank of 6 or more.Overall,the sensibility of biodegradation on diamondoids is generally similar to hopanes and regular steranes.As biodegradation evolves,the changes in concentration and components of diamondoids show that the biodegradation process is selective and stepwise.The significant increase of MD/MA and DMD/DMA for oils with a PM ranking 6^(+) indicates that diamantanes are generally more resistant to biodegradation than adamantanes.The similar trends of DMA/MA,EA/MA,MD/D,DMD/MD and other relevant indexes,show that higher alkylation homologs are more resistant to biodegradation.The commonly used diamondoid ratios,such as MAI,EAI,MDI and DMID-1,are obviously affected by biodegradation at the stage of high-level biodegradation,which may indicate that these ratios should be used with caution in case of severely degraded oils.展开更多
Global industrialization over the past centuries has resulted in widespread contamination of the environment with organic and inorganic wastes and their pattern of disposal.The study aimed at isolating fungi from spen...Global industrialization over the past centuries has resulted in widespread contamination of the environment with organic and inorganic wastes and their pattern of disposal.The study aimed at isolating fungi from spent diesel contaminated soil around Ministry of Works in Aba,Abia State for biodegradation potentials on the soil properties.About four(4)fungal species were isolated from the five(5)sites using cultural and biochemical characteristics.The isolate was screened,and optical density measured using spectrophotometer.A total of 5 soil samples from each location(0-15 cm and 15-30 cm)were collected and homogenized to have composite sample.Samples were taken to the laboratory for analysis of soil physiochemical parameters,fungi count and biodegradable potential of the fungi using standard methods.Data obtained revealed that,physical property of the soil such as sand(85.20%±0.01%),silk(6.4%±0.01%)were lower than the control location except clay(17.39%±0.01%).Chemical properties revealed highest concentration of element such as pH(4.76±0.01),total nitrogen(0.18%±0.011%),total organic carbon(3.41±0.01),sodium(0.21±0.01),potassium(0.24±0.001),magnesium(4.41±0.015),calcium(5.21±0.015),organic matter(6.18±0.011),and available phosphorus(30.99±0.01).All elements in the study site were higher than the control site with an exception to sodium(Na),which was lower.Fungi isolate identified were Aspergillus niger,Trichoderma virdae,Aspergillus flavus,and Pencillum corylophlum.The degradation potential of fungi identified shows that consortium degraded 29%of diesel oil from the soil followed by A.flavus,T.virdae,A.niger and the least was T.corylophlum.The study concludes that despite indiscriminate disposal of spent diesel oil,the nutrient content was still higher than control and consortium performed well in degradation.展开更多
The widespread use of polymers has made our lives increasingly convenient by offering a more convenient and dependable material.However,the challenge of efficiently decomposing these materials has resulted in a surge ...The widespread use of polymers has made our lives increasingly convenient by offering a more convenient and dependable material.However,the challenge of efficiently decomposing these materials has resulted in a surge of polymer waste,posing environment and health risk.Currently,landfill and incineration treatment approaches have notable shortcomings,prompting a shift towards more eco-friendly and sustainable biodegradation approaches.Biodegradation primarily relies on microorganisms,with research focusing on both solitary bacterial strain and multi-strain communities for polymer biodegradation.Furthermore,directed evolution and rational design of enzyme have significantly contributed to the polymer biodegradation process.However,previous reviews often undervaluing the role of multi-strain communities.In this review,we assess the current state of these three significant fields of research,provide practical solutions to issues with polymer biodegradation,and outline potential future directions for the subject.Ultimately,biodegradation,whether facilitated by single bacteria,multi-strain communities,or engineered enzymes,now represents the most effective method for managing waste polymers.展开更多
聚羟基脂肪酸酯(PHA)具有良好的生物降解性、生物相容性和可持续性,在包装、食品和医疗等领域具有广泛的应用前景。因此,亟待对国内外近二十余年来的有关PHA的研究进行总结和梳理,为PHA领域的协同发展提供理论依据。本研究以Web of Scie...聚羟基脂肪酸酯(PHA)具有良好的生物降解性、生物相容性和可持续性,在包装、食品和医疗等领域具有广泛的应用前景。因此,亟待对国内外近二十余年来的有关PHA的研究进行总结和梳理,为PHA领域的协同发展提供理论依据。本研究以Web of Science(WOS)核心合集数据库和中国知网(CNKI)全文数据库为数据检索源,借助CiteSpace和VOSviewer文献计量工具,对2000-2023年PHA领域的相关文献进行知识图谱的可视化分析。结果表明,在2000-2023年间,国内外对PHA领域的研究目前处于快速增长阶段,且英文文献的发文量和年增长率均显著高于中文文献。国际对该领域的关注度和研究要早于国内,并且我国在PHA领域的研究对全球贡献较大,但有影响力的研究较为缺乏,亟待进一步提高。关键词聚类和时空突现分析表明,未来的研究热点主要集中在以下3个方面:1)降低PHA生产成本以实现工业化生产;2)关注PHA降解酶的筛选与鉴定,以及PHA降解过程中的微生物群落结构和功能研究;3)PHA的共聚改性、复合改性以及与其他生物材料的功能化改性。展开更多
基金supported by the Natural Science Foundation of Chongqing(Grant No.csts2018jcyjAX0016)Funded by the Senior Medical Talents Program of Chongqing for Young and Middle-aged.
文摘The possible application of magnesium(Mg)in glaucoma surgical treatment has been investigated in our previous work.In this paper,the degradation behavior and biocompatibility of Mg coated with hydroxyapatite(HA)and dicalcium phosphate dihydrate(DCPD)in eye environment were evaluated,and uncoated Mg was used for comparison.It was found that uniform corrosion occurred macroscopically to the coated Mg samples in sodium lactate ringer’s injection(SLRI)as well as in the rabbit eyes.In micro-scale,the corrosion was characterized by local cracking and pitting primarily.Mg and calcium(Ca)were incorporated into the surface corrosion products and a multi-layer structure was formed.Compared to other samples,HA-coated Mg slowed down dramatically the alkalinity of the solution and the ion release of the sample,and exhibited the lowest corrosion rate in SLRI,which was about 0.22 mm/a.In terms of biocompatibility,fibroblasts demonstrated high viability in the HA-coated and DCPD-coated Mg groups(p<0.05)in vitro.In vivo,HA-coated Mg was found to show lower inflammatory response and fibrosis than the other groups did,as indicated by hematoxylin-eosin and immunofluorescence staining.During the degrading process of HA-coated Mg in the rabbits’eyes,no inflammation was found in the anterior chamber,lens,and vitreous body.HA-coated Mg was fully biodegraded fifteen weeks post-operation,and the scleral drainage channel(SDC)was formed without obvious scarring.It is concluded that HA-coated Mg implantation is a promising adjunctive procedure to improve the success rate of trabeculectomy.Statement of significance:Magnesium(Mg)has shown to be a potential biomaterial for ophthalmic implants in our previous work.However,inflammatory response resulted from the low corrosion resistance of Mg is a major concern.It is shown here that Mg coated with different calcium phosphates can improve these properties in varying degrees and keep the scleral drainage channel unobstructed and unscarred.Based on our in vitro and in vivo studies,HA-coated Mg exhibited a better degradation behavior and excellent biocompatibility.The scleral drainage channel still exists and aqueous humor flows out smoothly after the full degradation of the implant.It is concluded that HA-coated Mg is a promising biomaterial to increase the therapeutic efficiency of trabeculectomy for glaucoma.
基金supported by the National Natural Science Foundation of China(No.22241603).
文摘Insects have become an efficient and eco-friendly bioreactor for plastics and even micro/nano-plastics biodegradation.However,the optimal conditions for rearing insects to maximize plastic biodegradation and the underlying mechanisms remain unclear,hindering its practical applications.We investigated the effects of multiple rearing factors on plastics degradation efficiency of Tenebrio molitor larvae,including larval instar,water addition frequency,plastic specific surface area and plastic types.The functional gut microbes and enzymes associated with the improved efficiency were further explored.Our findings revealed that adult larvae achieved the highest plastics degradation efficiency when receiving regular water additions without causing drowning of insects on hydrophobic plastics.Additionally,they effectively ingested foam plastics of polystyrene,polyethylene and polyurethane without prior comminution and densification.The biodegradation processes involving oxidation,cleavage and depolymerization of plastics were all demonstrated.Furthermore,foam plastic type-dependent functional microbes and enzymes that contributed to the efficient plastic degradationwere identified.Thiswork provides valuable insights into the practical applications of insects for sustainable plastics biodegradation.
基金supported by the National Natural Science Foundation of China(Grants No.52270155 and 92047201).
文摘Cresyl diphenyl phosphate(CDP),an emerging aryl organophosphate ester(OPE),exhibits potential toxic effects and is frequently found in diverse environmental media,thereby raising concerns about environmental pollution.Biodegradation demonstrates substantial potential for CDP removal from the environment.This study investigated the biodegradation mechanisms of CDP using anaerobic activated sludge(AnAS).The biodegradation of 1-mg/L CDP followed a first-order kinetic model with a degradation kinetic constant of 0.943 d^(-1),and the addition of different electron acceptors affected the degradation rate.High-resolution mass spectrometry identified seven transformation products(TPs)of CDP.The pathways of CDP degradation in anaerobic conditions were proposed,with carboxylation products being the most dominant intermediate products.The structure of the anaerobic microbial community at different degradation time points in CDP-amended microcosms was examined.The linear discriminant analysis(LDA)of effect size(LEfSe)potentially underscored the pivotal role of Methyloversatilis in CDP biodegradation.Zebrafish embryotoxicity experiments revealed both lethal and morphogenetic impacts of CDP on zebrafish embryos.The survival rate,hatching rate,and body length indicators of zebrafish embryos underscored the detoxification of CDP and its resultant intermediates by AnAS.This study offers new insights into the fate and biodegradation mechanisms of CDP in wastewater treatment plants.
基金supported by the National Key Re-search and Development Project of China(No.2023YFC3108400).
文摘Bioremediation has gained significant attention due to its potential to remove azo dyes.However,the challenges microor-ganisms face in surviving when azo dyes are the sole carbon source limit its widespread application.This study aimed to improve the biodegradation of azo dyes by utilizing Baijiu distiller’s grains leachate(BDGL)as a co-substrate.The experimental results demon-strated that BDGL significantly enhanced Providencia rettgeri’s ability to degrade the model pollutant Acid Black 210(AB210),achieving a decolorization efficiency of 94.5%.This may be attributed to the nutrient-rich composition of BDGL,which includes ethanol and protein,providing a favorable substrate for bacterial growth and activity.The higher biomass and increased activities of azoreductase and quinone oxidoreductase in the BDGL group further supported these findings.Additionally,this method demonstra-ted broad-spectrum degradation of azo dyes(Direct Red 5B,Acid Red 73,and Congo Red)with different structures,highlighting its potential applicability.Metabolite assays combined with transcriptomics analyses revealed that the expression of functional genes re-lated to redox reactions,azo bond cleavage,and hydrolysis increased under the co-metabolic conditions of BDGL,resulting in stronger reducing power that further mineralized the dye into smaller metabolites.Our study offers a practical strategy for the simulta-neous treatment of dye-containing wastewater and Baijiu distiller’s grains,with significant environmental and industrial applications.
基金financial support of this paper by the Ministry of Education and Science of Ukraine under grant(Biotherm/0124U000789).
文摘The selection of carbon sources and the biosynthesis of polyhydroxybutyrate(PHB)by the Azotobacter vinelandii N-15 strain using renewable raw materials were investigated.Among the tested substrates(starch,sucrose,molasses,bran),molasses as the carbon source yielded the highest PHB production.The maximum polymer yield(26%of dry biomass)was achieved at a molasses concentration of 40 g/L.PHB formation was confirmed via thinlayer chromatography,gas chromatography and Fourier transform infrared spectroscopy.Composite films based on PHB,polylactic acid(PLA),and their blends were fabricated using the solvent casting.The biodegradation of these films was studied with bacteria isolated from plastic-contaminated soil.These bacteria utilized the biopolymers as their sole carbon source,with the biodegradation process lasting three months.Structural and chemical changes in the films were analyzed using FTIR spectroscopy,differential scanning calorimetry,and thermogravimetry.Among the microorganisms used to study the biodegradation of PHB,PLA,and their blends,Streptomyces sp.K2 and Streptomyces sp.K4 exhibited the highest biodegradation efficiency.PHB-containing films demonstrated significant advantages over other biodegradable polymers,as they degrade under aerobic conditions via enzymatic hydrolysis using microbial depolymerases.
基金supported by Natural Science Foundation of China(41907357)Natural Science Foundation of Shandong(ZR2019PC048)the Key R&D project of Shandong Province(2021TZXD007).
文摘Bioremediation of organophosphorus pesticides in contaminated foodstuffs using probiotics has been increasingly under the spotlight in recent years,though the biodegradation mechanism and derived intermediate products remain unclear.This study aimed to help fill this knowledge gap and examined the degradation mechanism of organophosphorus pesticide,chlorpyrifos,in milk by Lactobacillus delbrueckii ssp.bulgaricus using gas chromatography-tandem mass spectrometry(GC-MS/MS)combined with transcriptome analysis.After the strain was cultured for 20 h in the presence of chlorpyrifos,differential expressions of 383 genes were detected,including genes probably implicated during chlorpyrifos degradation such as those related to hydrolase,phosphoesterase,diphosphatase,oxidoreductase,dehydratase,as well as membrane transporters.GC-MS/MS analysis revealed the changes of secondary metabolites in L.bulgaricus during milk fermentation due to chlorpyrifos stress.6-Methylhexahydro-2H-azepin-2-one,2,6-dihydroxypyridine and methyl 2-aminooxy-4-methylpentanoate as intermediates,along with the proposed pathways,might be involved in chlorpyrifos biodegradation by L.bulgaricus.
基金the Bundesministerium für Bildung und Forschung(BMBF)-funded deNBI cloud within German Network for Bioinformatics Infrastructure(de.NBI)(Nos.031A532B,031A533A,031A533B,031A534A,031A535A,031A537A,031A537B,031A537C,031A537D,031A538A)for providing computational resources.Florin Musat was funded by the Helmholtz Association of German Research Centres Grant ERC-RA-0020+2 种基金the Novo Nordisk Foundation through an NNF Young Investigator Award,Grant NNF22OC0071609 ReFuel(grants to F.M.).Song-Can Chen is supported by Marie Skłodowska-Curie Actions 2021(postdoctoral fellowship 101059607 to S.C.C.).All sequencing data generated in this study have been deposited in the Sequence Read Archive under BioProject PRJNA1017987(SAMN37419328-SAMN374193).
文摘The Arctic,an essential ecosystem on Earth,is subject to pronounced anthropogenic pressures,most notable being the climate change and risks of crude oil pollution.As crucial elements of Arctic environments,benthic microbiomes are involved in climate-relevant biogeochemical cycles and hold the potential to remediate upcoming contamination.Yet,the Arctic benthic microbiomes are among the least explored biomes on the planet.Here we combined geochemical analyses,incubation experiments,and microbial community profiling to detail the biogeography and biodegradation potential of Arctic sedimentary microbiomes in the northern Barents Sea.The results revealed a predominance of bacterial and archaea phyla typically found in the deep marine biosphere,such as Chloroflexi,Atribacteria,and Bathyarcheaota.The topmost benthic communities were spatially structured by sedimentary organic carbon,lacking a clear distinction among geographic regions.With increasing sediment depth,the community structure exhibited stratigraphic variability that could be correlated to redox geochemistry of sediments.The benthic microbiomes harbored multiple taxa capable of oxidizing hydrocarbons using aerobic and anaerobic pathways.Incubation of surface sediments with crude oil led to proliferation of several genera from the so-called rare biosphere.These include Alkalimarinus and Halioglobus,previously unrecognized as hydrocarbon-degrading genera,both harboring the full genetic potential for aerobic alkane oxidation.These findings increase our understanding of the taxonomic inventory and functional potential of unstudied benthic microbiomes in the Arctic.
基金supported by the National Natural Science Foundation of China(Nos.21868011,42106144,42077444)the National Key R&D Program of China(No.2017YFC1103800)the financial support from Shandong University of Science and Technology(No.SKR19-1-012)。
文摘The degradation of tilmicosin(TLM),a semi-synthetic 16-membered macrolide antibiotic,has been receiving increasing attention.Conventionally,there are three tilmicosin degradation methods,and among them microbial degradation is considered the best due to its high efficiency,eco-friendliness,and low cost.Coincidently,we found a new strain,Glutamicibacter nicotianae sp.AT6,capable of degrading high-concentration TLM at 100 mg/L with a 97%removal efficiency.The role of tryptone was as well investigated,and the results revealed that the loading of tryptone had a significant influence on TLM removals.The toxicity assessment indicated that strain AT6 could efficiently convert TLM into less-toxic substances.Based on the identified intermediates,the degradation of TLM by AT6 processing through two distinct pathways was then proposed.
基金funded by the National Natural Science Foundation of China(No.42272160,No.41502133).
文摘The sensitivity of biodegradation on diamondoids was investigated using a series of biodegraded oil samples from the Ronier tectonic unit of Bongor Basin,Chad.The results suggest that diamondoids,including adamantanes(As)and diamantanes(Ds),are relatively resistant to biodegradation and obvious biodegradation was observed in oils with a Peters-Moldowan(PM)biodegradation rank of 6 or more.Overall,the sensibility of biodegradation on diamondoids is generally similar to hopanes and regular steranes.As biodegradation evolves,the changes in concentration and components of diamondoids show that the biodegradation process is selective and stepwise.The significant increase of MD/MA and DMD/DMA for oils with a PM ranking 6^(+) indicates that diamantanes are generally more resistant to biodegradation than adamantanes.The similar trends of DMA/MA,EA/MA,MD/D,DMD/MD and other relevant indexes,show that higher alkylation homologs are more resistant to biodegradation.The commonly used diamondoid ratios,such as MAI,EAI,MDI and DMID-1,are obviously affected by biodegradation at the stage of high-level biodegradation,which may indicate that these ratios should be used with caution in case of severely degraded oils.
文摘Global industrialization over the past centuries has resulted in widespread contamination of the environment with organic and inorganic wastes and their pattern of disposal.The study aimed at isolating fungi from spent diesel contaminated soil around Ministry of Works in Aba,Abia State for biodegradation potentials on the soil properties.About four(4)fungal species were isolated from the five(5)sites using cultural and biochemical characteristics.The isolate was screened,and optical density measured using spectrophotometer.A total of 5 soil samples from each location(0-15 cm and 15-30 cm)were collected and homogenized to have composite sample.Samples were taken to the laboratory for analysis of soil physiochemical parameters,fungi count and biodegradable potential of the fungi using standard methods.Data obtained revealed that,physical property of the soil such as sand(85.20%±0.01%),silk(6.4%±0.01%)were lower than the control location except clay(17.39%±0.01%).Chemical properties revealed highest concentration of element such as pH(4.76±0.01),total nitrogen(0.18%±0.011%),total organic carbon(3.41±0.01),sodium(0.21±0.01),potassium(0.24±0.001),magnesium(4.41±0.015),calcium(5.21±0.015),organic matter(6.18±0.011),and available phosphorus(30.99±0.01).All elements in the study site were higher than the control site with an exception to sodium(Na),which was lower.Fungi isolate identified were Aspergillus niger,Trichoderma virdae,Aspergillus flavus,and Pencillum corylophlum.The degradation potential of fungi identified shows that consortium degraded 29%of diesel oil from the soil followed by A.flavus,T.virdae,A.niger and the least was T.corylophlum.The study concludes that despite indiscriminate disposal of spent diesel oil,the nutrient content was still higher than control and consortium performed well in degradation.
基金supported by the National Natural Science Foundation of China(22078011,21908003,and 32022002)the National Key Research and Development Program of China(2021YFC2100600)+1 种基金the seed funding of China Petrochemical Corporation(Sinopec Group)(223260)the Fundamental Research Funds for the Central Universities(QNTD2023-01).
文摘The widespread use of polymers has made our lives increasingly convenient by offering a more convenient and dependable material.However,the challenge of efficiently decomposing these materials has resulted in a surge of polymer waste,posing environment and health risk.Currently,landfill and incineration treatment approaches have notable shortcomings,prompting a shift towards more eco-friendly and sustainable biodegradation approaches.Biodegradation primarily relies on microorganisms,with research focusing on both solitary bacterial strain and multi-strain communities for polymer biodegradation.Furthermore,directed evolution and rational design of enzyme have significantly contributed to the polymer biodegradation process.However,previous reviews often undervaluing the role of multi-strain communities.In this review,we assess the current state of these three significant fields of research,provide practical solutions to issues with polymer biodegradation,and outline potential future directions for the subject.Ultimately,biodegradation,whether facilitated by single bacteria,multi-strain communities,or engineered enzymes,now represents the most effective method for managing waste polymers.
文摘聚羟基脂肪酸酯(PHA)具有良好的生物降解性、生物相容性和可持续性,在包装、食品和医疗等领域具有广泛的应用前景。因此,亟待对国内外近二十余年来的有关PHA的研究进行总结和梳理,为PHA领域的协同发展提供理论依据。本研究以Web of Science(WOS)核心合集数据库和中国知网(CNKI)全文数据库为数据检索源,借助CiteSpace和VOSviewer文献计量工具,对2000-2023年PHA领域的相关文献进行知识图谱的可视化分析。结果表明,在2000-2023年间,国内外对PHA领域的研究目前处于快速增长阶段,且英文文献的发文量和年增长率均显著高于中文文献。国际对该领域的关注度和研究要早于国内,并且我国在PHA领域的研究对全球贡献较大,但有影响力的研究较为缺乏,亟待进一步提高。关键词聚类和时空突现分析表明,未来的研究热点主要集中在以下3个方面:1)降低PHA生产成本以实现工业化生产;2)关注PHA降解酶的筛选与鉴定,以及PHA降解过程中的微生物群落结构和功能研究;3)PHA的共聚改性、复合改性以及与其他生物材料的功能化改性。
