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Abnormal Proteoglycans Secreted by Chondrocytes in Actions of fulvic Acid and Reactive Oxygen Species

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Chinese Science Bulletin 1994年第13期39卷 1139-1142页

作者：李宏强许善锦常淑云王夔

Articular cartilage is an avascular and non-nervous tissue. The transport of metabolites to and from the chondrocytes has to take place through the matrix and hence depends on its composition and structure. A major pa... 详细信息

关键词： reactive oxygen species fulvic acid proteoglycan chondrocyte.

Study on Generation of Oxygen Free Radicals in Hepatocytes Induced by fulvic Acid

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Chinese Science Bulletin 1993年第23期38卷 2005-2008页

作者：张法浩李蓉许善锦王夔 School of Pharmaceutical Science Beijing Medical University Beijing 100083 PRC

fulvic acid (FA), a soluble fraction of the humic adds, is a group of polymers with a number of quinone moieties. It induces oxidative damage to cell, resulting in reduction of GSH-Px activity and increase of SOD activity in rat blood and liver or muscle tissues. This is possibly due to an interruption of the oxidation-antioxidation mechanism in cells.

关键词： fulvic acid hepatocyte free radical.

Interaction between fulvic acids of different origins and active oxygen radicals

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Science China(Life Sciences) 1996年第3期39卷 267-275页

作者：王春霞王子健彭安侯京武忻文娟 State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China) Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

Using the spin trapping technique, the interaction between fulvic acids (FAs) of different origins and the active oxygen radicals was studied. The active oxygen radicals under study included superoxide anion (O2 · -) produced by xanthine oxidase (XOD) and stimulated polymorphonuclear leukocytes (PMN) of human being and hydroxyl radical ( ·OH) produced from Fenton’s reaction. It has been found that the FAs from both Kaschin-Beck disease (KBD) region and non-KBD region can accelerate the production of ·OH and scavenge O2 ·- . FA from peat can scavenge both O2·- and ·OH. The results show that the behavior of KBD and non-KBD FAs differs clearly from peat FA. It has been concluded that the superoxidation damage of KBD induced by FA is mainly due to hydroxyl radical reaction initiated in biological system.

关键词： fulvic acids active oxygen radicals spin trapping Kaschin-Beck disease.

Redox-active humics support interspecies syntrophy and shift microbial community

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Science China(Technological Sciences) 2019年第10期62卷 1695-1702页

作者： ZHENG Yue KAPPLER Andreas XIAO Yong YANG Fan MAHADEVA Gurumurthy Dummi ZHAO Feng CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen361021China University of Chinese Academy of Sciences Beijing100049China Geomicrobiology Center for Applied GeosciencesUniversity of TuebingenTuebingen72076Germany

The network of microbial electron transfer can establish a syntrophic association of microbes by connecting interspecies metabolisms, and a variety of redox-active shuttles in environment have been proved to accelerate the electron flow in a microbial community. Using humic substances as models, we investigated how different redox-active shuttles with different electrochemical properties influence interspecies electron transfer, and affect the shift of microbial communities. The co-culture of two species was constructed with supplements of humics, and the electron transfer between these two strains was found to be linked by humic acid with a wider window of redox potential and multi-peaks of redox reactions. Based on the shift of microbial composition, the humic substances with a wide potential window and multi-peaks of redox reactions for accepting and donating electrons could increase the biodiversity(Chao 1 and phylogenetic diversity) with a large extent. The mechanism by which redox-active shuttles mediate the microbial electron transfer network could facilitate our understanding of syntrophic interactions between microbes.

关键词： humic acid fulvic acid redox-active shuttle microbial diversity interspecies electron transfer

Effects of pH value and coagulant dosage on contact filtration of humic substances

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Journal of Central South University 2009年第S1期16卷 384-390页

作者：蒋绍阶刘宗源梁建军 Key Laboratory of Three Gorges Reservoir Region's Eco-Environment Ministry of Education Shenzhen Institute of Building Research Co. Ltd.

Humic substances (especially fulvic acid (FA)) are the major components of natural organic matter (NOM) that widely exist in drinking water source. Due to their potential effects on public health,the removal of FA was one of the main concerns during the water treatment. Therefore,the contact filtration of FA by using aluminum sulfate as coagulant on the basis of jar tests was carried out. The effects of pH and coagulant dosage on the FA removal and the development of head loss were investigated. The results show that the range of pH value during the FA contact filtration can be effectively influenced by the dosage of aluminum sulfate,and the high aluminum sulfate dosage is an important factor that can result in early filter breakthrough. The FA filtration by deep-bed filtration or by membrane filtration is sometimes disparate under the same coagulation conditions. The choice of aluminum sulfate dosage by the method of membrane filtration,i.e. the "true color measurement",may result in inappropriate filter run,whereas it can be determined with simple jar tests by observing the formation of micro flocs. Considering the effects of pH on aluminum sulfate dosage and FA removal,the optimal pH range of 5.5?6.0 is suggested.

关键词： humic substances fulvic acid filtration coagulation

Quantitative and qualitative changes of humus in whole soils and their particle size fractions as influenced by different levels of compost application

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Agricultural Sciences 2011年第1期2卷 1-8页

作者： Thu Ha Nguyen Haruo Shindo 不详

Effect of long-term application (ca. 30 years) of compost at different levels on humus composi-tion of whole soils and their particle size frac-tions in a field subjected mainly to double cropping (barley and paddy rice) was investi-gated. Soil samples were collected from three plots of different types of management: (a) F plot, only chemical fertilizers containing N, P and K were applied;(b) F+LC plot, both chemi-cal fertilizers and a low level of compost were applied;(c) F+HC plot, both chemical fertilizers and a high level of compost were applied (the amount of compost applied in the F+HC plot was three times larger than that applied in the F+LC plot). Each soil sample was divided into coarse sand- (CSA), medium sand-(MSA) and fine sand-(FSA) sized aggregate, silt-sized ag-gregate (SIA) and clay-sized aggregate (CLA) fractions by wet-sieving and sedimentation. In addition, the CSA and MSA fractions were sub-divided into “mineral particles” (MP) and “de-cayed plants” (DP) by a density fractionation. Humus composition was influenced depending upon the level of compost applied. The applica-tion induced an increase in the amounts of total humus (TH), humic acid (HA) and fulvic acid (FA) in the whole soil and many size fractions, par-ticularly, SIA fraction. The increase was re-markable in the F+HC plot. In the CSA and MSA fractions, the amounts of TH, HA and FA were much larger in the CSA- and MSA-DP fractions than in the CSA- and MSA-MP fractions. The amounts of TH, HA and FA in the SIA fraction were larger than those in the CLA fraction for the F+HC and F+LC plots, and the reverse was true for the F plot. On the other hand, the de-grees of humification of humic acids in whole soils and many size fractions, particularly SIA fraction, decreased by compost application. The decrease was markedly in the F+HC plot. These findings suggest that the SIA fraction play an important role in the quantitative and qualitative changes of humus, including HA and FA, as in-fluenced

关键词： Paddy and Upland Fields Straw-Cow Dung Compost Humic and fulvic Acids Humification