Dissolved organic matter(DOM) plays an essential role in many geochemical processes,however its complexity, chemical diversity, and molecular composition are poorly understood. Soil samples were collected from 500 veg...Dissolved organic matter(DOM) plays an essential role in many geochemical processes,however its complexity, chemical diversity, and molecular composition are poorly understood. Soil samples were collected from 500 vegetable fields in administrative regions of China' Mainland, of which 122 were selected for further investigation. DOM properties were characterized by three-dimensional excitation-emission matrix(3D-EEM) fuorescence spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry(FTICRMS)(field intensity is 15 Tesla). Our results indicated that the main constituents were UVA humic-like substances, humic-like substances, fulvic acid-like substances, and tyrosine-like substances. A total of 10,989 molecular formulae with a mass range of 100.04 to 799.59 Da were detected, covering the mass spectrometric information of the soil samples from 27 different regions. CHO and CHON molecules were dominant in DOM, whereas lignin, tannins,and aromatic substances served as the main components. The results of cluster analysis revealed that the soil properties in Jiangxi Province were considerably different from those in other regions. The key backgrounds of the DOM molecular characteristics in the vegetablefield soil samples across China' Mainland were provided at the molecular level, with large abundance and great variability.展开更多
The dissemination of antibiotic resistance genes(ARGs)in soil has become a global environmental issue.Vermicomposting is gaining prominence in agricultural practices as a soil amendment to improve soil quality.However...The dissemination of antibiotic resistance genes(ARGs)in soil has become a global environmental issue.Vermicomposting is gaining prominence in agricultural practices as a soil amendment to improve soil quality.However,its impact on soil ARGs remains unclear when it occurs in farmland.We comprehensively explored the evolution and fate of ARGs and their hosts in the field soil profiles under vermicompost application for more than 3years.Vermicompost application increased several ARG loads in soil environment but decreased the high-risk bla-ARGs(bla_(ampC),bla_(NDM),and bla_(GES-1))by log(0.04-0.43).ARGs in soil amended with vermicompost primarily occurred in topsoil(approximately 1.04-fold of unfertilized soil),but it is worth noting that their levels in the 40-60 cm soil layer were the same or even less than in the unfertilized soil.The microbial community structure changed in soil profiles after vermicompost application.Vermicompost application altered the microbial community structure in soil profiles,showing that the dominant bacteria(i.e.,Proteobacteria,Actinobacteriota,Firmicutes)were decreased 2.62%-5.48%with the increase of soil depth.A network analysis further revealed that most of ARG dominant host bacteria did not migrate from surface soil to deep soil.In particular,those host bacteria harboring high-risk bla-ARGs were primarily concentrated in the surface soil.This study highlights a lower risk of the propagation of ARGs caused by vermicompost application and provides a novel approach to reduce and relieve the dissemination of ARGs derived from animals in agricultural production.展开更多
In the present study, we described a novel, simple, and scalable method for isolating and purifying natural mangiferin from fresh mango leaves. An ultrasonic-assisted method was used to extract mangiferin from mango l...In the present study, we described a novel, simple, and scalable method for isolating and purifying natural mangiferin from fresh mango leaves. An ultrasonic-assisted method was used to extract mangiferin from mango leaves using methanol as the solvent. The yields of the mangiferin crude extract and purified mangiferin recrystallized from a mixture of methanol and trichloromethane(10:1, v/v) were 1.41%(purity 86.5%) and 0.75%(purity > 99.6%), respectively. The purity of mangiferin was assessed by UV spectroscopy and HPLC. The structure of the purified compound was confirmed spectroscopically by UV, IR, Q-TOF/MS,;H NMR, and;C NMR. The method described herein to isolate mangiferin was simple, inexpensive, rapid, and efficient. Moreover, we, for the first time, obtained mangiferin with a purity of more than 99.6% using this method.展开更多
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program (STEP,No.2019QZKK0304)the Fundamental Research Funds for the Central Universities (No.E2EG0502×2)the Natural Science Foundation Committee of China (No.41991310)。
文摘Dissolved organic matter(DOM) plays an essential role in many geochemical processes,however its complexity, chemical diversity, and molecular composition are poorly understood. Soil samples were collected from 500 vegetable fields in administrative regions of China' Mainland, of which 122 were selected for further investigation. DOM properties were characterized by three-dimensional excitation-emission matrix(3D-EEM) fuorescence spectroscopy and Fourier transform ion cyclotron resonance mass spectrometry(FTICRMS)(field intensity is 15 Tesla). Our results indicated that the main constituents were UVA humic-like substances, humic-like substances, fulvic acid-like substances, and tyrosine-like substances. A total of 10,989 molecular formulae with a mass range of 100.04 to 799.59 Da were detected, covering the mass spectrometric information of the soil samples from 27 different regions. CHO and CHON molecules were dominant in DOM, whereas lignin, tannins,and aromatic substances served as the main components. The results of cluster analysis revealed that the soil properties in Jiangxi Province were considerably different from those in other regions. The key backgrounds of the DOM molecular characteristics in the vegetablefield soil samples across China' Mainland were provided at the molecular level, with large abundance and great variability.
基金supported by the National Natural Science Foundation of China(Nos.42077355,42277033)the Government Purchasing Project of the Ministry of Agriculture and Rural Affairs(No.15228002)the Major Science and Technology Project of Yunnan Province(No.202102AE090011)。
文摘The dissemination of antibiotic resistance genes(ARGs)in soil has become a global environmental issue.Vermicomposting is gaining prominence in agricultural practices as a soil amendment to improve soil quality.However,its impact on soil ARGs remains unclear when it occurs in farmland.We comprehensively explored the evolution and fate of ARGs and their hosts in the field soil profiles under vermicompost application for more than 3years.Vermicompost application increased several ARG loads in soil environment but decreased the high-risk bla-ARGs(bla_(ampC),bla_(NDM),and bla_(GES-1))by log(0.04-0.43).ARGs in soil amended with vermicompost primarily occurred in topsoil(approximately 1.04-fold of unfertilized soil),but it is worth noting that their levels in the 40-60 cm soil layer were the same or even less than in the unfertilized soil.The microbial community structure changed in soil profiles after vermicompost application.Vermicompost application altered the microbial community structure in soil profiles,showing that the dominant bacteria(i.e.,Proteobacteria,Actinobacteriota,Firmicutes)were decreased 2.62%-5.48%with the increase of soil depth.A network analysis further revealed that most of ARG dominant host bacteria did not migrate from surface soil to deep soil.In particular,those host bacteria harboring high-risk bla-ARGs were primarily concentrated in the surface soil.This study highlights a lower risk of the propagation of ARGs caused by vermicompost application and provides a novel approach to reduce and relieve the dissemination of ARGs derived from animals in agricultural production.
基金The Key R&D projects in Hainan Province (Grant No. ZDYF2020160)the National Key Research and Development Project of China (Grant No. 2017YFF0207800)Central Public-interest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences (Grant No. 1630082017001)。
文摘In the present study, we described a novel, simple, and scalable method for isolating and purifying natural mangiferin from fresh mango leaves. An ultrasonic-assisted method was used to extract mangiferin from mango leaves using methanol as the solvent. The yields of the mangiferin crude extract and purified mangiferin recrystallized from a mixture of methanol and trichloromethane(10:1, v/v) were 1.41%(purity 86.5%) and 0.75%(purity > 99.6%), respectively. The purity of mangiferin was assessed by UV spectroscopy and HPLC. The structure of the purified compound was confirmed spectroscopically by UV, IR, Q-TOF/MS,;H NMR, and;C NMR. The method described herein to isolate mangiferin was simple, inexpensive, rapid, and efficient. Moreover, we, for the first time, obtained mangiferin with a purity of more than 99.6% using this method.
