The dissolved organic matter(DOM)with high mobility and reactivity plays a crucial role in soil.In this study,the characteristics and phytotoxicity ofDOMreleased fromthe hydrochars prepared from different feedstocks(c...The dissolved organic matter(DOM)with high mobility and reactivity plays a crucial role in soil.In this study,the characteristics and phytotoxicity ofDOMreleased fromthe hydrochars prepared from different feedstocks(cowmanure,corn stalk and Myriophyllum aquaticum)under three hydrothermal carbonization(HTC)temperatures(180,200 and 220°C)were evaluated.The results showed that the hydrochars had high dissolved organic carbon content(20.15 to 37.65 mg/g)and its content showed a gradual reduction as HTC temperature increased.Three fluorescent components including mixed substance of fulvic acid-like and humic acid-like substances(C1,30.92%-58.32%),UVA humic acid-like substance(C2,25.27%-29.94%)and protein-like substance(C3,11.74%-41.92%)were identified in hydrochar DOM by excitation emission matrix spectra coupled with parallel factor analysis.High HTC temperature increased the relative proportion of aromatic substances(C1+C2)and humification degree of hydrochar DOM from cow manure,while it presented adverse effects on the hydrochar DOM from corn stalk and Myriophyllum.aquaticum.The principal component analysis suggested that feedstock type and HTC temperature posed significant effects on the characteristics of hydrochar DOM.Additionally,seed germination test of all hydrochar DOM demonstrated that the root length was reduced by 8.88%-26.43%in contrast with control,and the germination index values were 73.57%-91.12%.These findings provided new insights into the potential environmental effects for hydrochar application in soil.展开更多
Zeolite imidazole frameworks(ZIFs),a class of the metal organic framework,have been extensively studied in environmental applications.However,their environmental fate and potential ecological impact on plants remain u...Zeolite imidazole frameworks(ZIFs),a class of the metal organic framework,have been extensively studied in environmental applications.However,their environmental fate and potential ecological impact on plants remain unknown.Here,we investigated the phytotoxicity,transformation,and bioaccumulation processes of two typical ZIFs(ZIF-8 and ZIF-67)in rice(Oryza sativa L.)under hydroponic conditions.ZIF-8 and ZIF-67 in the concentration of 50 mg/L decreased root and shoot dry weight maximally by 55.2%and 27.5%,53.5%and 37.5%,respectively.The scanning electron microscopy(SEM)imaging combined with X-ray diffraction(XRD)patterns revealed that ZIFs on the root surface gradually collapsed and transformed into nanosheets with increasing cultivation time.The fluorescein isothiocyanate(FITC)labeled ZIFs were applied to trace the uptake and translocation of ZIFs in rice.The results demonstrated that the transformed ZIFs were mainly distributed in the intercellular spaces of rice root,while they cannot be transported to culms and leaves.Even so,the Co and Zn contents of rice roots and shoots in the ZIFs treated groups were increased by 1145%and 1259%,145%and 259%,respectively,compared with the control groups.These findings suggested that the phytotoxicity of ZIFs are primarily attributed to the transformed ZIFs and to a less extent,the metal ions and their ligands,and they were internalized by rice root and increased the Co and Zn contents of shoots.This study reported the transformation of ZIFs and their biological effectiveness in rice,highlighting the potential environmental hazards and risks of ZIFs to crop plants.展开更多
Three main phytotoxic compounds including lunatoic acid A (1), 5Z-7-oxozeaenol (2) and zeaenol (3) were isolated from the fermentation broth of Cladosporium oxysporum DH14, a fungus residing in the locust (Oxya...Three main phytotoxic compounds including lunatoic acid A (1), 5Z-7-oxozeaenol (2) and zeaenol (3) were isolated from the fermentation broth of Cladosporium oxysporum DH14, a fungus residing in the locust (Oxya chinensis ) gut. Two additional derivative compounds, compound la and lb, were synthesized by methylation and chlorination of compound 1, respectively. The structures of such compounds were identified on the basis of spectroscopic analysis and by comparison of the corresponding data to those previously reported in the literature. Compounds 1-3 exhibited significantly phytotoxic activities against the radicle growth of Amaranthus retroflexus L. with the 50% inhibitory concentrations (ICso values) of 4.51, 4.80 and 8.16 μg· mL^-1, respectively, which is comparable to that positive control 2,4-dichlorophenoxyacetic acid (IC50=1.95 μg· mL^-1). Furthermore, the compound 1 showed selective phytotoxic activity with the inhibition rate of less than 22% against the crops of Brassica rapa L., Sorghum durra, Brassica campestris L,, Capsicum annucm and Raphanus safivus L. under the concentration of 100 μg· mL^-1 Both derivatives of compound 1 had moderate phytotoxic activity against the radicle growth of A. retroflexus L. The findings of our present study suggest that these compounds provide new promising candidates for the potential management strategies of weeds.展开更多
At the global scale,foliar metal transfer occurs for consumed vegetables cultivated in numerous urban or industrial areas with a polluted atmosphere.However,the kinetics of metal uptake,translocation and involved phyt...At the global scale,foliar metal transfer occurs for consumed vegetables cultivated in numerous urban or industrial areas with a polluted atmosphere.However,the kinetics of metal uptake,translocation and involved phytotoxicity was never jointly studied with vegetables exposed to micronic and sub-micronic particles(PM).Different leafy vegetables(lettuces and cabbages)cultivated in RHIZOtest?devices were,therefore,exposed in a greenhouse for 5,10 and 15 days to various Pb O PM doses.The kinetics of transfer and phytotoxicity was assessed in relation to lead concentration and exposure duration.A significant Pb accumulation in leaves(up to 7392 mg/kg dry weight(DW)in lettuce)with translocation to roots was observed.Lead foliar exposure resulted in significant phytotoxicity,lipid composition change,a decrease of plant shoot growth(up to 68.2%in lettuce)and net photosynthesis(up to 58%in lettuce).The phytotoxicity results indicated plant adaptation to Pb and a higher sensitivity of lettuce in comparison with cabbage.Air quality needs,therefore,to be considered for the health and quality of vegetables grown in polluted areas,such as certain megacities(in China,Pakistan,Europe,etc.)and furthermore,to assess the health risks associated with their consumption.展开更多
Seedling emergence tests were conducted in a meadow brown soil using five plant species(i.e., Chinese cabbage, green onion, tomato, turnip and wheat) to determine the phytotoxicity of phenanthrene, pyrene and their mi...Seedling emergence tests were conducted in a meadow brown soil using five plant species(i.e., Chinese cabbage, green onion, tomato, turnip and wheat) to determine the phytotoxicity of phenanthrene, pyrene and their mixtures. The soil was amended with up to 1000 mg/kg soil of phenanthrene or 600 mg/kg soil of pyrene. Seedling emergence and root growth were measured. The results indicated that root elongation was more sensitive than seedling emergence. Root length decreased with increasing phenanthrene or pyrene concentrations(p≤0 05). Phenanthrene was more phytotoxic than pyrene. The lowest observable adverse effect concentration(LOAEC) was 10 mg/kg for phenanthrene when tested with green onion, and 50 mg/kg for pyrene when tested with wheat. Among the five species, wheat was found to be the most sensitive. When amended jointly at or below their respective LOAEC, phenanthrene and pyrene produced a synergistic toxic effect.展开更多
The bioavailability of bound residue(BR) derived from 14 C-labeled chlorsulfuron in soil and effect of the main components of the BR on growth of rape(brassica napus) and rice(Oryza sativa L.) were investigat...The bioavailability of bound residue(BR) derived from 14 C-labeled chlorsulfuron in soil and effect of the main components of the BR on growth of rape(brassica napus) and rice(Oryza sativa L.) were investigated. The results showed that the BR with the concentration of 0 28 and 0 56 nmol/g air-dried soil, which was calculated by special radioactivity of 14 C-labeled chlorsulfuron parent compound, resulted in significant depression effect on growth of rape seedling. It was assured that the main components(2-amino-4-methoxyl-6-methyl-1,3,5-triazine, 2-amino-4-hydroxyl-6-methyl-1,3,5-triazine, and 2-chloro-benzenesul-f onamide) of the BR did not inhibit the growth of rape and rice. LC-MS analysis demonstrated that the parent compound previously bound to the soil matrix could be again released and transformed into methanol-extractable residue during the course of rape growth. It was concluded that the molecular leading to the phytotoxicity to rape and rice in the BR is still the parent compound.展开更多
A pot experiment was catried out to study alleviation of soil acidity and Al toxicity by applying analkaline-stabilised sewage sludge product (biosolids) to an acid clay sandy loam (pH 5.7) and a strongly acidsandy lo...A pot experiment was catried out to study alleviation of soil acidity and Al toxicity by applying analkaline-stabilised sewage sludge product (biosolids) to an acid clay sandy loam (pH 5.7) and a strongly acidsandy loam (pH 4.5). Barley (Hondeum vulgare L. cv. Forrester) was used as a test crop and was grownin the sewage sludge-amended (33.5 t sludge DM ha-1) and unamended soils. The results showed that thealka1ine biosloids increased soil pH from 5.7 to 6.9 for the clay sandy loam and from 4.5 to 6.0 for the sandyloam. The sludge product decreased KCl-extractable Al from 0.1 to 0.0 cmol kg-1 for the former soil andfrom 4.0 to 0.1 cmol kg-1 for the latter soil. As a result, barley plants grew much better and grain yieldincreased greatly in the amended treatments compared with the unamended controls. These observationsindicate that alkaline-stabilised biosolids can be used as a liming material for remedying Al phytotoxicity instrongly acid soils by increasing soil pH and lowering Al bioavailability.展开更多
The physiological effects of 4 herbicides (butachlor, quinclorac, bensulfuron-methyl and atrazine) on 3 submerged macrophytes (Ceratophyllum demersum, Vallisneria natans and Elodea nuttallii) were tested in labora...The physiological effects of 4 herbicides (butachlor, quinclorac, bensulfuron-methyl and atrazine) on 3 submerged macrophytes (Ceratophyllum demersum, Vallisneria natans and Elodea nuttallii) were tested in laboratory. The variables of the relative growth rate and the photosynthetic pigment content showed that all of the tested herbicides affected the growth of the plants obviously, even at the lowest concentration (0.0001 mg/L). Except for the C. demersum treated with quinclorac at 0.005 and 0.01 mg/L, the relative growth rates of the plants were inhibited significantly (p 〈 0.01). Statistical analysis of chlorophyll a (Chl-a) contents was carded out with both the t-test and one-way ANOVA to determine the difference between the treatment and control. The results showed that Chl-a contents of the plants in all treatment groups were affected by herbicides significantly, except for the C. demersum treated with bensulfuron-methyl at 0.0005 mg/L. The decrease in Chl-a content was positively correlated to the dosage of the herbicides in most treatment groups. It was suggested that herbicides in water bodies might potentially affect the growth of aquatic macrophytes. Since the Chl-a content of submerged macrophytes responded to the stress of herbicides sensitively and directly, it could be used as a biomaker in environmental monitoring or in the ecological risk assessment of herbicide contamination.展开更多
Aerial parts of Xanthium italicum in an air tight container greatly inhibited root elongation of radish, implying that this invasive plant could release biologically active volatile organic compounds (VOCs) into the...Aerial parts of Xanthium italicum in an air tight container greatly inhibited root elongation of radish, implying that this invasive plant could release biologically active volatile organic compounds (VOCs) into the environment to affect other plants' growth. This phenomenon was further studied by evaluating the phytotoxic effects of X. italicum essential oil against two dicot plants, amaranth (Amaranthus mangostanus L.) and lettuce (Lectuca sativa L.), and two monocot plants, wheat (Triticum aestivum Linn) and ryegrass (Lolium multiforum), and analyzing the chemical composition of the oil. Among the 4 test species, amaranth was the most sensitive plant, 0.5μl/mL essential oil application resulted in a 50% reduction on root elongation, and 2.5 μl/mL essential oil almost completely inhibited its seedling growth. Wheat was the least sensitive species, whose root growth was reduced to 36% of control by 5 μl/mL essential oil. The essential oil exerted moderate inhibitory effect on both lettuce and ryegrass. Compared to a commercial herbicide-Harness, X. italicum oil exhibited stronger phytotoxicity on amaranth, lettuce and wheat, but weaker activity on ryegrass. The chemical composition of the essential oil isolated by hydrodistillation from the aerial parts of X. italicum Moretti was analyzed by GC/MS. Thirty two compounds were identified, representing 94.89% of total oil, which was found to be rich in monoterpene hydrocarbons (60.71%). The main constituents of the oil were limonene (51.61%), germacrene B (6.98%), 6-cadinol (5.94%), β-pinene (5.23%), α-caryophyllene (5.1%) and bornyl acetate (3.15%). Bioassay revealed the dominant constituent-limonene, was unlikely the responsible phytotoxic compound due to its low biological activity; rather, there might be other oil constituent(s) that either act alone, or work together, and possibly assisted by synergistic effect, to display the phytotoxic activity. Our results suggested that X. italicum might produce allelopathic VOCs to facilitate its invasion success. This is the first report on the phytotoxic activity and the chemical composition of the essential oil of X. itaficum Moretti from China.展开更多
The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and...The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of the both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic matter (OM) became predominance for Zn and organic bound Cu occupied the largest portion. There was more available amount for Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to AEXCH and ACAR forms but also in AOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by AEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.展开更多
Essential oils of the resins of Pinus brutia and Pinus pinea were evaluated for their biological potential. Essential oils were characterized using GC-MS and GC/FID. In vitro antimicrobial, phytotoxic, antioxidant, an...Essential oils of the resins of Pinus brutia and Pinus pinea were evaluated for their biological potential. Essential oils were characterized using GC-MS and GC/FID. In vitro antimicrobial, phytotoxic, antioxidant, and insecticidal activities were carried out using the direct contact and the fumigant assays, respectively. The chemical profile of the essential oils of the resins of P. pinea and P. brutia included mainly α-pinene(21.39% and 25.40%), β-pinene(9.68% and 9.69%), and caryophyllene(9.12% and 4.81%). The essential oils of P. pinea and P. brutia exerted notable antimicrobial activities on Micrococcus luteus and Bacillus subtilis, insecticidal activities on Ephestia kuehniella eggs, phytotoxic activities on Lactuca sativa, Lepidium sativum, and Portulaca oleracea, as well as antioxidant potential. Indications of the biological activities of the essential oils suggest their use in the formulation of ecofriendly and biocompatible pharmaceuticals.展开更多
Decomposition of plant litter is a fundamental process in ecosystem function, carbon and nutrient cycling and, by extension, climate change. This study aimed to investigate the role of temperature on the decomposition...Decomposition of plant litter is a fundamental process in ecosystem function, carbon and nutrient cycling and, by extension, climate change. This study aimed to investigate the role of temperature on the decomposition of water soluble phenolics(WSP), carbon and soil nutrients in conjunction with the phytotoxicity dynamics of Chrysanthemoides monilifera subsp. monilifera(boneseed) litter. Treatments consisted of three factors including decomposition materials(litter alone, litter with soil and soil alone), decomposition periods and temperatures(5-15, 15-25and 25-35°C(night/day)). Leachates were collected on 0, 5, 10, 20, 40 and 60 th days to analyse physico-chemical parameters and phytotoxicity. Water soluble phenolics and dissolved organic carbon(DOC) increased with increasing temperature while nutrients like SO-24 and NO-13 decreased. Speed of germination, hypocotyl and radical length and weight of Lactuca sativa exposed to leachates were decreased with increasing decomposition temperature. All treatment components had significant effects on these parameters. There had a strong correlation between DOC and WSP, and WSP content of the leachates with radical length of test species. This study identified complex interactivity among temperature, WSP, DOC and soil nutrient dynamics of litter occupied soil and that these factors work together to influence phytotoxicity.展开更多
OBJECTIVE: Plants produce a variety of useful bio- active materials that have been used to cure differ- ent ailments of human beings. With the same idea in mind, the crude methanolic extract and various fractions of ...OBJECTIVE: Plants produce a variety of useful bio- active materials that have been used to cure differ- ent ailments of human beings. With the same idea in mind, the crude methanolic extract and various fractions of Solanum surrattense were screened for antibacterial, antifungal, phytotoxic and heamag- glutination activities. METHODS: Standardized assays were followed for the determination of antibacterial, antifungal phy- totoxic and heamagglutination activity. RESULTS: The results of the antibacterial showed that crude methanolic extract was significantly ac- tive against Staphylococcus aureus (86%) The n- hexane fraction showed good activity against Pseu- domonas aerogenosa (66.6%) and Bacillus subtilus (66.6%). The crude methanolic extract and various fractions were inactive against all test fungi. The crude methanolic extract, n-hexane, CHCI3 and aqueous fractions showed moderate phytotoxic ac- tivities of 46.67%, 40.00%, 33.34% and 33.34% re- spectively at 1000 pg/mL. The crude methanolic ex- tract and various fractions S. surrattense were un- able to aqqlutinate RBCs of the human blood indi-cating that this species lack phytolectins. CONCLUSION: The test sample showed significant antibacterial activity, no antifungal and heamagglu- tination activity while moderate phytotoxic was ob- served against Lemna minor L.展开更多
Photooxidative removal of pharmaceuticals and organic dyes is an effective way to eliminate growing micropollutants. However, photooxidation often results in byproducts as secondary hazardous substances such as phytot...Photooxidative removal of pharmaceuticals and organic dyes is an effective way to eliminate growing micropollutants. However, photooxidation often results in byproducts as secondary hazardous substances such as phytotoxins. Herein, we found that photooxidation of common antibiotic tetracycline hydrochloride(TCH) over a metal-free 8-hydroxyquinoline(8-HQ) functionalized carbon nitride(CN) photocatalyst significantly reduces the TCH phytotoxic effect. The phytotoxicity test of photocatalytic treated TCH-solution evaluated towards seed growth of Cicer arietinum plant model endowed natural root and shoot growth.This study highlights the conceptual insights in designing of metal-free photocatalyst for environmental remediation.展开更多
Chromium is found in all phases of the environment, including air, water and soil. The contamination of environment by chromium has become a major area of concern. Chromium effluent is highly toxic to plant and is har...Chromium is found in all phases of the environment, including air, water and soil. The contamination of environment by chromium has become a major area of concern. Chromium effluent is highly toxic to plant and is harmful to their growth and development. In present study, a pot experiment was carried out to assess the phytotoxicity of chromium in Hibiscus esculentus at different concentration (0.5, 2.5, 5, 10, 25, 50 and 100 mg·kg-1) of chromium metal. The phytotoxic effect of chromium was observed on seed germination, seedling growth, seedling vigor index, chlorophyll content and tolerance indices of Hibiscus esculentus. All results when compared with control show that chromium metal adversely affects the growth of Hibiscus esculentus by reducing seed germination and decreasing seedling growth. The toxic effects of chromium metal to seed germination and young seedling are arranged in order of inhibition as: 0.5 > 2.5 > 5 > 10 > 25 > 50 > 100 mg·kg-1 respectively. The toxicity of chromium metal to young seedling and their effects on chlorophyll content were increased with higher concentration of chromium in the soil system. The major inhibitory effect of chromium in Hibiscus esculentus seedling was determined as stress tolerance index (%). The present study represents that the seed and seedling of Hibiscus esculentus has potential to counteract the deleterious effects of chromium metal in soil.展开更多
Soil contaminated with pesticides may reduce plant development due to their toxicity. The aim of this study was to evaluate the influence on the germination of </span><i><span style="font-family:Ve...Soil contaminated with pesticides may reduce plant development due to their toxicity. The aim of this study was to evaluate the influence on the germination of </span><i><span style="font-family:Verdana;">Zea mayz</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Phaseolus vulgaris </span></i><span style="font-family:Verdana;">of the two main intermediates of the 2,4-D degradation, which are 4-chlorophenol (4-CP) and 2,4-dichlorophenol (2,4-DCP). Maize and bean seeds were treated with distilled water (control treatment) and increased concentrations of 4-CP and 2,4-DCP (0.006, 0.1, 1.0, 1.5 g·L</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">). It was assessed seed germination and calculated various parameters. The parameter most affected by chlorophenols was the index of germination rate, being the </span><i><span style="font-family:Verdana;">P. vulgaris</span></i><span style="font-family:Verdana;"> seeds most affected. 2,4-DCP was the compound most toxic for both plants. The germination index was dependent </span><span style="font-family:Verdana;">doses for both plant models tested. The results indicate that 4-CP and</span><span style="font-family:Verdana;"> 2,4-DCP affected the index of germination rate but not influenced in other parameters of germination of </span><i><span style="font-family:Verdana;">Zea mayz</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Phaseolus vulgaris.</span></i><span style="font-family:Verdana;"> Maize was </span><span style="font-family:Verdana;">most tolerance to both chlorophenols in the assessed concentrations. 2,4-DCP </span><span style="font-family:Verdana;">was the most toxic of chlorophenols tested.展开更多
OBJECTIVE: To investigate the antimicrobial activity, hemagglutination and phytotoxic activity of crude ethanolic and aqueous extracts of Seriphidium kurramense.METHODS: The extracts were analyzed by agar well diffusi...OBJECTIVE: To investigate the antimicrobial activity, hemagglutination and phytotoxic activity of crude ethanolic and aqueous extracts of Seriphidium kurramense.METHODS: The extracts were analyzed by agar well diffusion assays against five bacterial species:Staphylococcus aureus(S. aureus), methicillin-resistant S. aureus, Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, and Salmonella typhi. The extracts were also screened against six fungal species — Aspergillus niger, Aspergillus flavus, Alternaria solani, Rhizoctonia solani, Fusarium solani and Pleurotus florida — using the agar tube diffusion method. Additionally, hemagglutination and phytotoxic activities of the crude ethanolic and aqueous extracts were assessed.RESULTS: The crude ethanolic and aqueous extracts showed dose-dependent inhibition of the various tested fungal and bacterial strains. No hemagglutination activity was observed. Both the ethanolic and aqueous extracts showed dose-dependent phytotoxic activity toward Lemna minor.CONCLUSION: The crude ethanolic and aqueous extracts of Seriphidium kurramense possess good antimicrobial and phytotoxic activities, but no hemagglutination activity.展开更多
OBJECTIVE:To evaluate Sterculia diversifolia stem bark and leaves for phytotoxic,genotoxic and enzymes inhibition potential.METHODS:Phytotoxic activity of both stem bark and leaves were screened using Lemna minor.The ...OBJECTIVE:To evaluate Sterculia diversifolia stem bark and leaves for phytotoxic,genotoxic and enzymes inhibition potential.METHODS:Phytotoxic activity of both stem bark and leaves were screened using Lemna minor.The genotoxic activity of Sterculia diversifolia stem bark and leaves extracts were tested using comet assay protocol while enzyme inhibition activity of crude extract and various fractions of both stem bark and leaves were evaluated using acetyl cholinesterase,lipoxygenase,β-glucuronidase,urease,xanthine oxidase and carbonic anhydrase.RESULTS:Phytotoxic activity showed significant results in dose dependant manner in both stem bark(ethyl acetate and n-butanol)and leaves(ethyl acetate,nbutanol and n-hexane)fractions.In genotoxic activity,dichloromethane fraction showed significant activity followed by ethyl acetate fraction.Acetyl cholinesterease inhibitory activity showed significant results in both stem bark and leaves fractions,while significant lipoxygenase inhibition was shown by ethyl acetate,dichloromethane,crude extract and n-hexane fractions of both stem bark and leaves.β-glucuronidase,urease and carbonic anhydrase inhibitory activity showed highly significant results in ethyl acetate fraction of both stem bark and leaves,while xanthine oxidase inhibition was shown by dichloromethane fraction of stem bark and leaves extracts.CONCLUSIONS:This study emphasizes the important phytotoxic,genotoxic and enzyme inhibition effects of Sterculia diversifolia stem bark and leaves.Hence,it is clear that Sterculia diversifolia stem bark and leaves possess phytotoxic,genotoxic and enzyme inhibitory agents.展开更多
Hydrothermal technology (HT) has received much attention in recent years as a process to convert wet organic waste into hydrochar.The aqueous phase (HTAP) produced by this process is still a burden and has become a bo...Hydrothermal technology (HT) has received much attention in recent years as a process to convert wet organic waste into hydrochar.The aqueous phase (HTAP) produced by this process is still a burden and has become a bottleneck issue for HT process development.In this study,we provide the?rst investigation of the HTAP characteristics,phytotoxicity,and their correlation with persulfate (PS)(PS,2.0 mmol/g TS)-assisted municipal sludge HT.The results showed that PS accelerated the hydrolysis of protein substances and increased the concentration of NH_(4)^(+)by 13.4%to 190.5%and that of PO_(4)^(3-)by 24.2%to 1103.7%in HTAP at hydrothermal temperatures of 120 to 240℃.PS can reduce the phytotoxicity of HTAP by reducing aldehydes,ketones,N heterocyclic compounds,and particle size and by increasing its humi?cation index.The maximum values of the root length and biomass of pakchoi(Brassica chinensis L.) seedlings occurred when electrical conductivity was 0.2 mS/cm of HTAP.This work provided a new strategy for the selection and design of HTAP management strategies.展开更多
A pot experiment was carried out to study the effect of trace elements on the biuret toxicity of maize, with the aim to provide theoretical basis for improving the urea-based compound fertilizer production and reducin...A pot experiment was carried out to study the effect of trace elements on the biuret toxicity of maize, with the aim to provide theoretical basis for improving the urea-based compound fertilizer production and reducing the biuret toxicity. The results showed that the compound fertilizer with 2% and 4% biuret caused obvious toxicity on the maize. The plant became short, and the biomass decreased, and the toxicity phenomenon of maize would become more obvious when the biuret leve increased. Application of 5% EDTA-Zn and 0.4% B could reduce the toxicity of bi uret in fertilizers. The toxicity would be eliminated completely when the level of biuret was 2% in compound fertilizers, while the toxicity effects of 4% biuret was just alleviated to a certain extent. In addition, application of 2% amino acids with ureabased compound fertilizer could promote root absorption of biuret, and increase the biuret toxicity. In conclusion, the urea compound fertilizers with high biuret concentrations should be applied with appropriate trace elements to reduce the biuret dam age. It was suggested that the biuret content in the complex fertilizers for maize should be controlled below 2%, and appropriate trace elements should be applied at the same time.展开更多
基金supported by the Director Fund Project provided by the Institute of Plant Nutrition,Resources and Environment,Beijing Academy of Agriculture and Forestry Sciences(No.YZS202101)the Youth Fund Project provided by Beijing Academy of Agriculture and Forestry Sciences(No.QNJJ202125)China Agriculture Research System of MOF and MARA.
文摘The dissolved organic matter(DOM)with high mobility and reactivity plays a crucial role in soil.In this study,the characteristics and phytotoxicity ofDOMreleased fromthe hydrochars prepared from different feedstocks(cowmanure,corn stalk and Myriophyllum aquaticum)under three hydrothermal carbonization(HTC)temperatures(180,200 and 220°C)were evaluated.The results showed that the hydrochars had high dissolved organic carbon content(20.15 to 37.65 mg/g)and its content showed a gradual reduction as HTC temperature increased.Three fluorescent components including mixed substance of fulvic acid-like and humic acid-like substances(C1,30.92%-58.32%),UVA humic acid-like substance(C2,25.27%-29.94%)and protein-like substance(C3,11.74%-41.92%)were identified in hydrochar DOM by excitation emission matrix spectra coupled with parallel factor analysis.High HTC temperature increased the relative proportion of aromatic substances(C1+C2)and humification degree of hydrochar DOM from cow manure,while it presented adverse effects on the hydrochar DOM from corn stalk and Myriophyllum.aquaticum.The principal component analysis suggested that feedstock type and HTC temperature posed significant effects on the characteristics of hydrochar DOM.Additionally,seed germination test of all hydrochar DOM demonstrated that the root length was reduced by 8.88%-26.43%in contrast with control,and the germination index values were 73.57%-91.12%.These findings provided new insights into the potential environmental effects for hydrochar application in soil.
基金This work was supported by the National Natural Science Foundation of China(Nos.30800705 and 31101599)the Provincial Natural Science Foundation of Zhejiang(Nos.LY15C150004 and LY18C150007)the Key Research and Devel opment Projects of Social Development of Jinhua Science and Technology Program(No.2021C22750).
文摘Zeolite imidazole frameworks(ZIFs),a class of the metal organic framework,have been extensively studied in environmental applications.However,their environmental fate and potential ecological impact on plants remain unknown.Here,we investigated the phytotoxicity,transformation,and bioaccumulation processes of two typical ZIFs(ZIF-8 and ZIF-67)in rice(Oryza sativa L.)under hydroponic conditions.ZIF-8 and ZIF-67 in the concentration of 50 mg/L decreased root and shoot dry weight maximally by 55.2%and 27.5%,53.5%and 37.5%,respectively.The scanning electron microscopy(SEM)imaging combined with X-ray diffraction(XRD)patterns revealed that ZIFs on the root surface gradually collapsed and transformed into nanosheets with increasing cultivation time.The fluorescein isothiocyanate(FITC)labeled ZIFs were applied to trace the uptake and translocation of ZIFs in rice.The results demonstrated that the transformed ZIFs were mainly distributed in the intercellular spaces of rice root,while they cannot be transported to culms and leaves.Even so,the Co and Zn contents of rice roots and shoots in the ZIFs treated groups were increased by 1145%and 1259%,145%and 259%,respectively,compared with the control groups.These findings suggested that the phytotoxicity of ZIFs are primarily attributed to the transformed ZIFs and to a less extent,the metal ions and their ligands,and they were internalized by rice root and increased the Co and Zn contents of shoots.This study reported the transformation of ZIFs and their biological effectiveness in rice,highlighting the potential environmental hazards and risks of ZIFs to crop plants.
基金the National Natural Science Foundation of China (NSFC) (21002092 and 21272215)the Open Project of State Key Laboratory of Pharmaceutical Biotechnology in Nanjing University, China (KF-GN-201411)
文摘Three main phytotoxic compounds including lunatoic acid A (1), 5Z-7-oxozeaenol (2) and zeaenol (3) were isolated from the fermentation broth of Cladosporium oxysporum DH14, a fungus residing in the locust (Oxya chinensis ) gut. Two additional derivative compounds, compound la and lb, were synthesized by methylation and chlorination of compound 1, respectively. The structures of such compounds were identified on the basis of spectroscopic analysis and by comparison of the corresponding data to those previously reported in the literature. Compounds 1-3 exhibited significantly phytotoxic activities against the radicle growth of Amaranthus retroflexus L. with the 50% inhibitory concentrations (ICso values) of 4.51, 4.80 and 8.16 μg· mL^-1, respectively, which is comparable to that positive control 2,4-dichlorophenoxyacetic acid (IC50=1.95 μg· mL^-1). Furthermore, the compound 1 showed selective phytotoxic activity with the inhibition rate of less than 22% against the crops of Brassica rapa L., Sorghum durra, Brassica campestris L,, Capsicum annucm and Raphanus safivus L. under the concentration of 100 μg· mL^-1 Both derivatives of compound 1 had moderate phytotoxic activity against the radicle growth of A. retroflexus L. The findings of our present study suggest that these compounds provide new promising candidates for the potential management strategies of weeds.
基金financial support from Ademe(the French Agency of Sustainable Development and Energy)through the"DIMENSION"projectthe National Research Agency under reference ANR-12-0011-VBDUthe National Polytechnic Institute in Toulouse(INPT)
文摘At the global scale,foliar metal transfer occurs for consumed vegetables cultivated in numerous urban or industrial areas with a polluted atmosphere.However,the kinetics of metal uptake,translocation and involved phytotoxicity was never jointly studied with vegetables exposed to micronic and sub-micronic particles(PM).Different leafy vegetables(lettuces and cabbages)cultivated in RHIZOtest?devices were,therefore,exposed in a greenhouse for 5,10 and 15 days to various Pb O PM doses.The kinetics of transfer and phytotoxicity was assessed in relation to lead concentration and exposure duration.A significant Pb accumulation in leaves(up to 7392 mg/kg dry weight(DW)in lettuce)with translocation to roots was observed.Lead foliar exposure resulted in significant phytotoxicity,lipid composition change,a decrease of plant shoot growth(up to 68.2%in lettuce)and net photosynthesis(up to 58%in lettuce).The phytotoxicity results indicated plant adaptation to Pb and a higher sensitivity of lettuce in comparison with cabbage.Air quality needs,therefore,to be considered for the health and quality of vegetables grown in polluted areas,such as certain megacities(in China,Pakistan,Europe,etc.)and furthermore,to assess the health risks associated with their consumption.
文摘Seedling emergence tests were conducted in a meadow brown soil using five plant species(i.e., Chinese cabbage, green onion, tomato, turnip and wheat) to determine the phytotoxicity of phenanthrene, pyrene and their mixtures. The soil was amended with up to 1000 mg/kg soil of phenanthrene or 600 mg/kg soil of pyrene. Seedling emergence and root growth were measured. The results indicated that root elongation was more sensitive than seedling emergence. Root length decreased with increasing phenanthrene or pyrene concentrations(p≤0 05). Phenanthrene was more phytotoxic than pyrene. The lowest observable adverse effect concentration(LOAEC) was 10 mg/kg for phenanthrene when tested with green onion, and 50 mg/kg for pyrene when tested with wheat. Among the five species, wheat was found to be the most sensitive. When amended jointly at or below their respective LOAEC, phenanthrene and pyrene produced a synergistic toxic effect.
文摘The bioavailability of bound residue(BR) derived from 14 C-labeled chlorsulfuron in soil and effect of the main components of the BR on growth of rape(brassica napus) and rice(Oryza sativa L.) were investigated. The results showed that the BR with the concentration of 0 28 and 0 56 nmol/g air-dried soil, which was calculated by special radioactivity of 14 C-labeled chlorsulfuron parent compound, resulted in significant depression effect on growth of rape seedling. It was assured that the main components(2-amino-4-methoxyl-6-methyl-1,3,5-triazine, 2-amino-4-hydroxyl-6-methyl-1,3,5-triazine, and 2-chloro-benzenesul-f onamide) of the BR did not inhibit the growth of rape and rice. LC-MS analysis demonstrated that the parent compound previously bound to the soil matrix could be again released and transformed into methanol-extractable residue during the course of rape growth. It was concluded that the molecular leading to the phytotoxicity to rape and rice in the BR is still the parent compound.
基金National Natural Science Foundation of China(Nos.49831070 and 40125005)theNational Key Basic Research Support Foundation of China(No.G1999011807) the Jiangsu Provincial Foundation for Young Scientists(No.BQ98050).
文摘A pot experiment was catried out to study alleviation of soil acidity and Al toxicity by applying analkaline-stabilised sewage sludge product (biosolids) to an acid clay sandy loam (pH 5.7) and a strongly acidsandy loam (pH 4.5). Barley (Hondeum vulgare L. cv. Forrester) was used as a test crop and was grownin the sewage sludge-amended (33.5 t sludge DM ha-1) and unamended soils. The results showed that thealka1ine biosloids increased soil pH from 5.7 to 6.9 for the clay sandy loam and from 4.5 to 6.0 for the sandyloam. The sludge product decreased KCl-extractable Al from 0.1 to 0.0 cmol kg-1 for the former soil andfrom 4.0 to 0.1 cmol kg-1 for the latter soil. As a result, barley plants grew much better and grain yieldincreased greatly in the amended treatments compared with the unamended controls. These observationsindicate that alkaline-stabilised biosolids can be used as a liming material for remedying Al phytotoxicity instrongly acid soils by increasing soil pH and lowering Al bioavailability.
基金supported by the Hi-Tech Re-search and Development Program (863) of China (No.2007AA06A405)the National Basic Research Pro-gram (973) Project of China (No. 2002CB412307)
文摘The physiological effects of 4 herbicides (butachlor, quinclorac, bensulfuron-methyl and atrazine) on 3 submerged macrophytes (Ceratophyllum demersum, Vallisneria natans and Elodea nuttallii) were tested in laboratory. The variables of the relative growth rate and the photosynthetic pigment content showed that all of the tested herbicides affected the growth of the plants obviously, even at the lowest concentration (0.0001 mg/L). Except for the C. demersum treated with quinclorac at 0.005 and 0.01 mg/L, the relative growth rates of the plants were inhibited significantly (p 〈 0.01). Statistical analysis of chlorophyll a (Chl-a) contents was carded out with both the t-test and one-way ANOVA to determine the difference between the treatment and control. The results showed that Chl-a contents of the plants in all treatment groups were affected by herbicides significantly, except for the C. demersum treated with bensulfuron-methyl at 0.0005 mg/L. The decrease in Chl-a content was positively correlated to the dosage of the herbicides in most treatment groups. It was suggested that herbicides in water bodies might potentially affect the growth of aquatic macrophytes. Since the Chl-a content of submerged macrophytes responded to the stress of herbicides sensitively and directly, it could be used as a biomaker in environmental monitoring or in the ecological risk assessment of herbicide contamination.
基金financially supported by the International Science and Technology Cooperation Program of China (2010 DFA 92720-06)the One Hundred Person Project of the Chinese Academy of Sciences granted to Chi ZHANGthe West Light Foundation of the Chinese Academy of Sciences granted to Hua SHAO (LHXZ201202)
文摘Aerial parts of Xanthium italicum in an air tight container greatly inhibited root elongation of radish, implying that this invasive plant could release biologically active volatile organic compounds (VOCs) into the environment to affect other plants' growth. This phenomenon was further studied by evaluating the phytotoxic effects of X. italicum essential oil against two dicot plants, amaranth (Amaranthus mangostanus L.) and lettuce (Lectuca sativa L.), and two monocot plants, wheat (Triticum aestivum Linn) and ryegrass (Lolium multiforum), and analyzing the chemical composition of the oil. Among the 4 test species, amaranth was the most sensitive plant, 0.5μl/mL essential oil application resulted in a 50% reduction on root elongation, and 2.5 μl/mL essential oil almost completely inhibited its seedling growth. Wheat was the least sensitive species, whose root growth was reduced to 36% of control by 5 μl/mL essential oil. The essential oil exerted moderate inhibitory effect on both lettuce and ryegrass. Compared to a commercial herbicide-Harness, X. italicum oil exhibited stronger phytotoxicity on amaranth, lettuce and wheat, but weaker activity on ryegrass. The chemical composition of the essential oil isolated by hydrodistillation from the aerial parts of X. italicum Moretti was analyzed by GC/MS. Thirty two compounds were identified, representing 94.89% of total oil, which was found to be rich in monoterpene hydrocarbons (60.71%). The main constituents of the oil were limonene (51.61%), germacrene B (6.98%), 6-cadinol (5.94%), β-pinene (5.23%), α-caryophyllene (5.1%) and bornyl acetate (3.15%). Bioassay revealed the dominant constituent-limonene, was unlikely the responsible phytotoxic compound due to its low biological activity; rather, there might be other oil constituent(s) that either act alone, or work together, and possibly assisted by synergistic effect, to display the phytotoxic activity. Our results suggested that X. italicum might produce allelopathic VOCs to facilitate its invasion success. This is the first report on the phytotoxic activity and the chemical composition of the essential oil of X. itaficum Moretti from China.
基金Project supported by the Provincial Technique Program of Zhejiang Province(No.2004c23024)the Key Science and Technology Program of Hangzhou City(No.2005113A07).
文摘The potential harm of heavy metals is a primary concern in application of sludge to the agricultural land. A pot experiment was conducted to evaluate the effect of two sludges on fractionation of Zn and Cu in soil and their phytotoxicity to pakchoi. The loamy soil was mixed with 0%, 20%, 40%, 60% and 80% (by weight) of digested sewage sludge (SS) and composted sludge (SC). The additions of the both sludges caused a significant raise in all fractions, resulting in that exchangeable (EXCH) and organic matter (OM) became predominance for Zn and organic bound Cu occupied the largest portion. There was more available amount for Zn and Cu in SS treatments than SC treatments. During the pot experiment, the concentration of Zn in EXCH, carbonate (CAR) and OM and Cu in EXCH and OM fractions decreased in all treatments, so their bioavailability reduced. Germination rate and plant biomass decreased when the addition rate was high and the best yield appeared in 20% mixtures at the harvest of pakchoi. The two sludges increased tissue contents of Zn and Cu especially in the SS treatments. Zn in pakchoi was not only in relationship to AEXCH and ACAR forms but also in AOM forms in the sludge-soil mixtures. Tissue content of Cu in pakchoi grown on SC-soils could not be predicted by AEXCH. These correlation rates between Zn and Cu accumulation in pakchoi and variation of different fractions increased with time, which might indicate that sludges represented stronger impacts on the plant in long-term land application.
基金supported by the Scientific Research Fund(OKU-BAP)of Osmaniye Korkut Ata University,Osmaniye,Turkey
文摘Essential oils of the resins of Pinus brutia and Pinus pinea were evaluated for their biological potential. Essential oils were characterized using GC-MS and GC/FID. In vitro antimicrobial, phytotoxic, antioxidant, and insecticidal activities were carried out using the direct contact and the fumigant assays, respectively. The chemical profile of the essential oils of the resins of P. pinea and P. brutia included mainly α-pinene(21.39% and 25.40%), β-pinene(9.68% and 9.69%), and caryophyllene(9.12% and 4.81%). The essential oils of P. pinea and P. brutia exerted notable antimicrobial activities on Micrococcus luteus and Bacillus subtilis, insecticidal activities on Ephestia kuehniella eggs, phytotoxic activities on Lactuca sativa, Lepidium sativum, and Portulaca oleracea, as well as antioxidant potential. Indications of the biological activities of the essential oils suggest their use in the formulation of ecofriendly and biocompatible pharmaceuticals.
文摘Decomposition of plant litter is a fundamental process in ecosystem function, carbon and nutrient cycling and, by extension, climate change. This study aimed to investigate the role of temperature on the decomposition of water soluble phenolics(WSP), carbon and soil nutrients in conjunction with the phytotoxicity dynamics of Chrysanthemoides monilifera subsp. monilifera(boneseed) litter. Treatments consisted of three factors including decomposition materials(litter alone, litter with soil and soil alone), decomposition periods and temperatures(5-15, 15-25and 25-35°C(night/day)). Leachates were collected on 0, 5, 10, 20, 40 and 60 th days to analyse physico-chemical parameters and phytotoxicity. Water soluble phenolics and dissolved organic carbon(DOC) increased with increasing temperature while nutrients like SO-24 and NO-13 decreased. Speed of germination, hypocotyl and radical length and weight of Lactuca sativa exposed to leachates were decreased with increasing decomposition temperature. All treatment components had significant effects on these parameters. There had a strong correlation between DOC and WSP, and WSP content of the leachates with radical length of test species. This study identified complex interactivity among temperature, WSP, DOC and soil nutrient dynamics of litter occupied soil and that these factors work together to influence phytotoxicity.
文摘OBJECTIVE: Plants produce a variety of useful bio- active materials that have been used to cure differ- ent ailments of human beings. With the same idea in mind, the crude methanolic extract and various fractions of Solanum surrattense were screened for antibacterial, antifungal, phytotoxic and heamag- glutination activities. METHODS: Standardized assays were followed for the determination of antibacterial, antifungal phy- totoxic and heamagglutination activity. RESULTS: The results of the antibacterial showed that crude methanolic extract was significantly ac- tive against Staphylococcus aureus (86%) The n- hexane fraction showed good activity against Pseu- domonas aerogenosa (66.6%) and Bacillus subtilus (66.6%). The crude methanolic extract and various fractions were inactive against all test fungi. The crude methanolic extract, n-hexane, CHCI3 and aqueous fractions showed moderate phytotoxic ac- tivities of 46.67%, 40.00%, 33.34% and 33.34% re- spectively at 1000 pg/mL. The crude methanolic ex- tract and various fractions S. surrattense were un- able to aqqlutinate RBCs of the human blood indi-cating that this species lack phytolectins. CONCLUSION: The test sample showed significant antibacterial activity, no antifungal and heamagglu- tination activity while moderate phytotoxic was ob- served against Lemna minor L.
基金the department of science and technology fund for improvement of science and technology infrastructure (DST FIST) (No. SR/FST/CSI-279/2016(C)) for providing XRD and UV-DRS facilitiesthe department of science and technology science and engineering research board (DST-SERB) through the project (No. SB/EMEQ-052/2014 SERB) for financial assistancethe Director, Visvesvaraya National Institute of Technology (VNIT) Nagpur for financial support。
文摘Photooxidative removal of pharmaceuticals and organic dyes is an effective way to eliminate growing micropollutants. However, photooxidation often results in byproducts as secondary hazardous substances such as phytotoxins. Herein, we found that photooxidation of common antibiotic tetracycline hydrochloride(TCH) over a metal-free 8-hydroxyquinoline(8-HQ) functionalized carbon nitride(CN) photocatalyst significantly reduces the TCH phytotoxic effect. The phytotoxicity test of photocatalytic treated TCH-solution evaluated towards seed growth of Cicer arietinum plant model endowed natural root and shoot growth.This study highlights the conceptual insights in designing of metal-free photocatalyst for environmental remediation.
文摘Chromium is found in all phases of the environment, including air, water and soil. The contamination of environment by chromium has become a major area of concern. Chromium effluent is highly toxic to plant and is harmful to their growth and development. In present study, a pot experiment was carried out to assess the phytotoxicity of chromium in Hibiscus esculentus at different concentration (0.5, 2.5, 5, 10, 25, 50 and 100 mg·kg-1) of chromium metal. The phytotoxic effect of chromium was observed on seed germination, seedling growth, seedling vigor index, chlorophyll content and tolerance indices of Hibiscus esculentus. All results when compared with control show that chromium metal adversely affects the growth of Hibiscus esculentus by reducing seed germination and decreasing seedling growth. The toxic effects of chromium metal to seed germination and young seedling are arranged in order of inhibition as: 0.5 > 2.5 > 5 > 10 > 25 > 50 > 100 mg·kg-1 respectively. The toxicity of chromium metal to young seedling and their effects on chlorophyll content were increased with higher concentration of chromium in the soil system. The major inhibitory effect of chromium in Hibiscus esculentus seedling was determined as stress tolerance index (%). The present study represents that the seed and seedling of Hibiscus esculentus has potential to counteract the deleterious effects of chromium metal in soil.
文摘Soil contaminated with pesticides may reduce plant development due to their toxicity. The aim of this study was to evaluate the influence on the germination of </span><i><span style="font-family:Verdana;">Zea mayz</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Phaseolus vulgaris </span></i><span style="font-family:Verdana;">of the two main intermediates of the 2,4-D degradation, which are 4-chlorophenol (4-CP) and 2,4-dichlorophenol (2,4-DCP). Maize and bean seeds were treated with distilled water (control treatment) and increased concentrations of 4-CP and 2,4-DCP (0.006, 0.1, 1.0, 1.5 g·L</span><sup><span style="font-family:Verdana;">-1</span></sup><span style="font-family:Verdana;">). It was assessed seed germination and calculated various parameters. The parameter most affected by chlorophenols was the index of germination rate, being the </span><i><span style="font-family:Verdana;">P. vulgaris</span></i><span style="font-family:Verdana;"> seeds most affected. 2,4-DCP was the compound most toxic for both plants. The germination index was dependent </span><span style="font-family:Verdana;">doses for both plant models tested. The results indicate that 4-CP and</span><span style="font-family:Verdana;"> 2,4-DCP affected the index of germination rate but not influenced in other parameters of germination of </span><i><span style="font-family:Verdana;">Zea mayz</span></i><span style="font-family:Verdana;"> and </span><i><span style="font-family:Verdana;">Phaseolus vulgaris.</span></i><span style="font-family:Verdana;"> Maize was </span><span style="font-family:Verdana;">most tolerance to both chlorophenols in the assessed concentrations. 2,4-DCP </span><span style="font-family:Verdana;">was the most toxic of chlorophenols tested.
文摘OBJECTIVE: To investigate the antimicrobial activity, hemagglutination and phytotoxic activity of crude ethanolic and aqueous extracts of Seriphidium kurramense.METHODS: The extracts were analyzed by agar well diffusion assays against five bacterial species:Staphylococcus aureus(S. aureus), methicillin-resistant S. aureus, Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, and Salmonella typhi. The extracts were also screened against six fungal species — Aspergillus niger, Aspergillus flavus, Alternaria solani, Rhizoctonia solani, Fusarium solani and Pleurotus florida — using the agar tube diffusion method. Additionally, hemagglutination and phytotoxic activities of the crude ethanolic and aqueous extracts were assessed.RESULTS: The crude ethanolic and aqueous extracts showed dose-dependent inhibition of the various tested fungal and bacterial strains. No hemagglutination activity was observed. Both the ethanolic and aqueous extracts showed dose-dependent phytotoxic activity toward Lemna minor.CONCLUSION: The crude ethanolic and aqueous extracts of Seriphidium kurramense possess good antimicrobial and phytotoxic activities, but no hemagglutination activity.
文摘OBJECTIVE:To evaluate Sterculia diversifolia stem bark and leaves for phytotoxic,genotoxic and enzymes inhibition potential.METHODS:Phytotoxic activity of both stem bark and leaves were screened using Lemna minor.The genotoxic activity of Sterculia diversifolia stem bark and leaves extracts were tested using comet assay protocol while enzyme inhibition activity of crude extract and various fractions of both stem bark and leaves were evaluated using acetyl cholinesterase,lipoxygenase,β-glucuronidase,urease,xanthine oxidase and carbonic anhydrase.RESULTS:Phytotoxic activity showed significant results in dose dependant manner in both stem bark(ethyl acetate and n-butanol)and leaves(ethyl acetate,nbutanol and n-hexane)fractions.In genotoxic activity,dichloromethane fraction showed significant activity followed by ethyl acetate fraction.Acetyl cholinesterease inhibitory activity showed significant results in both stem bark and leaves fractions,while significant lipoxygenase inhibition was shown by ethyl acetate,dichloromethane,crude extract and n-hexane fractions of both stem bark and leaves.β-glucuronidase,urease and carbonic anhydrase inhibitory activity showed highly significant results in ethyl acetate fraction of both stem bark and leaves,while xanthine oxidase inhibition was shown by dichloromethane fraction of stem bark and leaves extracts.CONCLUSIONS:This study emphasizes the important phytotoxic,genotoxic and enzyme inhibition effects of Sterculia diversifolia stem bark and leaves.Hence,it is clear that Sterculia diversifolia stem bark and leaves possess phytotoxic,genotoxic and enzyme inhibitory agents.
基金supported by the National Natural Science Foundation of China (No. 42030704)。
文摘Hydrothermal technology (HT) has received much attention in recent years as a process to convert wet organic waste into hydrochar.The aqueous phase (HTAP) produced by this process is still a burden and has become a bottleneck issue for HT process development.In this study,we provide the?rst investigation of the HTAP characteristics,phytotoxicity,and their correlation with persulfate (PS)(PS,2.0 mmol/g TS)-assisted municipal sludge HT.The results showed that PS accelerated the hydrolysis of protein substances and increased the concentration of NH_(4)^(+)by 13.4%to 190.5%and that of PO_(4)^(3-)by 24.2%to 1103.7%in HTAP at hydrothermal temperatures of 120 to 240℃.PS can reduce the phytotoxicity of HTAP by reducing aldehydes,ketones,N heterocyclic compounds,and particle size and by increasing its humi?cation index.The maximum values of the root length and biomass of pakchoi(Brassica chinensis L.) seedlings occurred when electrical conductivity was 0.2 mS/cm of HTAP.This work provided a new strategy for the selection and design of HTAP management strategies.
基金Supported by the National Science&Technology Pillar Program during the Twelfth Fiveyear Plan Period(2011BAD11B02)the Special Fund for the Independent Innovation in Shandong Province(2012CX90202)~~
文摘A pot experiment was carried out to study the effect of trace elements on the biuret toxicity of maize, with the aim to provide theoretical basis for improving the urea-based compound fertilizer production and reducing the biuret toxicity. The results showed that the compound fertilizer with 2% and 4% biuret caused obvious toxicity on the maize. The plant became short, and the biomass decreased, and the toxicity phenomenon of maize would become more obvious when the biuret leve increased. Application of 5% EDTA-Zn and 0.4% B could reduce the toxicity of bi uret in fertilizers. The toxicity would be eliminated completely when the level of biuret was 2% in compound fertilizers, while the toxicity effects of 4% biuret was just alleviated to a certain extent. In addition, application of 2% amino acids with ureabased compound fertilizer could promote root absorption of biuret, and increase the biuret toxicity. In conclusion, the urea compound fertilizers with high biuret concentrations should be applied with appropriate trace elements to reduce the biuret dam age. It was suggested that the biuret content in the complex fertilizers for maize should be controlled below 2%, and appropriate trace elements should be applied at the same time.