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171.
Turci F Favero-Longo SE Tomatis M Martra G Castelli D Piervittori R Fubini B 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(14):4081-4093
Some lichens were recently reported to modify the surface state of asbestos. Here we report some new insight on the physico-chemical modifications induced by natural chelators (lichen metabolites) on two asbestos samples collected in two different locations. A biomimetic approach was followed by reproducing in the laboratory the weathering effect of lichen metabolites. Norstictic, pulvinic and oxalic acid (0.005, 0.5 and 50 mM) were put in contact with chrysotile fibres, either in pure form (A) or intergrown with balangeroite, an iron-rich asbestiform phase (B). Mg and Si removal, measured by inductively coupled plasma atomic emission spectrometry (ICP-AES) and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), reveals an incongruent dissolution for pure chrysotile (A), with Mg removal always exceeding that of Si, while chrysotile-balangeroite (B) follows a congruent dissolution pattern in all cases except in the presence of 50 mM oxalic acid. A much larger removal of Mg than Si in the solutions of 0.5 and 50 mM oxalic acid with chrysotile (A) suggests a structural collapse, which in the case of chrysotile-balangeroite (B) only occurs with 50 mM oxalic acid; in these cases both samples are converted into amorphous silica (as detected by X-ray diffraction (XRD)). Subsequent to incubation, some new phases (Fe(2)O(3), CaMg(CO(3))(2), Ca(C(2)O(4)) x H(2)O and Mg(C(2)O(4))2 x H(2)O), similar to those observed in the field, were detected by XRD and micro-Raman spectroscopy. The leaching effect of lichen metabolites also modifies the Fenton activity, a process widely correlated with asbestos pathogenicity: pure chrysotile (A) activity is reduced by 50 mM oxalic acid, while all lichen metabolites reduce the activity of chrysotile-balangeroite (B). The selective removal of poorly coordinated, highly reactive iron ions, evidenced by NO adsorption, accounts for the loss in Fenton activity. Such fibres were chemically close to the ones observed in the field. Chrysotile-rich rocks, colonised by lichens, could be exposed to a natural bioattenuation and considered as a transient environmental hazard. 相似文献
172.
The mutual responses of higher plants to environment: physiological and microbiological aspects 总被引:3,自引:0,他引:3
Gang W Zhen-Kuan W Yong-Xiang W Li-Ye C Hong-Bo S 《Colloids and surfaces. B, Biointerfaces》2007,59(2):113-119
Higher plants are different from animals in many aspects, but the important difference may be that plants are more easily influenced by environment. Plants have a series of fine mechanisms for responding to environmental changes, which has been established during their long-period evolution and artificial domestication. The relationship between higher plants and environment is influenced mutually. The component in environment provides higher plants with nutrients for shaping themselves and higher plants simultaneously bring photosynthetic products and metabolites to surroundings, which is the most important part of natural circle. Photosynthetic products are realized mainly by physiological mechanisms, and microbiological aspects in environment (for instance, soil environment) impact the above processes greatly. The complete understanding of the relationship will extremely promote the sustainable utilization of plant resources and make the best use of its current potential under different scales. 相似文献
173.
Julia Martín Carmen Mejías Juan Luis Santos Irene Aparicio Esteban Alonso 《Molecules (Basel, Switzerland)》2021,26(19)
This work evaluated the availability and sorption behaviour of four pharmaceuticals and eight of their metabolites in sewage sludge and sludge-amended soil. Digested sludge and compost were evaluated. The highest levels found in digested sludge corresponded to caffeine (up to 115 ng g−1 dm), ibuprofen (45 ng g−1 dm) and carbamazepine (9.3 ng g−1 dm). The concentrations measured in compost were even lower than in digested sludge. No compound was detected in sludge-amended soils. This fact could be due to the dilution effect after sludge application to soil. Different adsorption capacities in sludge–soil mixtures were measured for the studied compounds at the same spike concentration. In general, except for paraxanthine and 3-hydroxycarbamazepine, the metabolite concentrations measured in the mixtures were almost two-fold lower than those of their parent compounds, which can be explained by their mobility and lixiviation tendency. The log Kd ranged from −1.55 to 1.71 in sludge samples and from −0.29 to 1.18 in soil–sludge mixtures. The log Kd values calculated for compost were higher than those calculated for digested sludge. The obtained results implied that the higher organic carbon content of compost could influence soil contamination when it is applied to soil. 相似文献
174.
175.
An HPLC method is described for separation of TNT and its main reduction metabolites. Two columns(LC-C(18) and LC-CN)are connected in series and operated isocratically at 1.0mL/min with water-methanol-tetrahydrofuran(60+ 35+ 5 ). The baseline separation of 4-amino-2,6-dinitrotoluene(4A) and 2-amino-4,6-dinitrotoluene(2A) ,which are main metabolites of TNT,is obtained(Rs=2.1). 相似文献
176.
杀螨王及其代谢物残留总量的气相色谱分析法 总被引:4,自引:0,他引:4
报道了杀螨王(fenpyroximate)及其代谢物顺式体在HCl-H2SO4混合液中定量分解为可经气相色谱分析的1,3-二甲基-5-苯氧基吡唑-4-醛,建立了苹果、柑桔和土壤样品中残留总量的气相色谱分析法。添加浓度0.05~1.0mg/kg,苹果、桔皮、桔肉和土壤样品中杀螨王总量平均回收率分别为104.7~124.8%,90.9~93.8%,89.3~94.0%和104.3~113.0%,变异系数依次为3.3~11.8%,2.7~7.5%,1.4~2.7%和1.5~4.0%。 相似文献
177.
Shengsheng Lu Jianan Hu Xi Xie Runhong Zhou Fangfang Li Ruifeng Huang Jian He 《Molecules (Basel, Switzerland)》2021,26(24)
A new aliphatic acid, compound 1, together with six known metabolites, including nonactic acid (2), homononactic acid (3), ethyl homononactate (4), homononactylhomononactate (5), valinomycin (6), and cyclo-(Pro-Leu) (7), was isolated from the culture broth of Streptomyces sp. BM-8, an actinobacterial strain isolated from the feces of Equus quagga. The structures of these compounds were established by analyses of spectroscopic data, including 1D and 2D nuclear magnetic resonance spectra (NMR), as well as by HR-ESI-MS spectrometry and chemical derivative analyses. Additionally, a serial analogue of nonactic acid and homononacticacid (8–21) was synthesized. The cytotoxicity of 1–21 wastested against a panel of cancer cell lines, such as HT-29, MCF-7, A375 and K562, with MTT assay. In addition, the cytotoxicity tests revealed that 1 was less cytotoxic toward a panel of cancerous cells, as compared with valinomycin (6). 相似文献
178.
建立了同时检测人尿液中7种邻苯二甲酸酯代谢物的高效液相色谱-串联三重四极杆质谱法。尿液经酶水解后,采用萃取柱净化,以2%(v/v)甲酸甲醇溶液为洗脱剂,经苯基柱分离,以0.1%(v/v)乙酸水溶液和0.1%(v/v)乙酸乙腈溶液为流动相进行梯度洗脱,采用电喷雾离子源负离子模式和多反应监测模式采集信号,用同位素内标法进行定量分析。尿液中7种邻苯二甲酸酯代谢物在0.2~200.0 μg/L范围内定量离子的相对峰面积比值与质量浓度均呈良好线性关系(r≥0.99976);检出限(LOD)为13.43~80.21 ng/L,定量限为44.77~267.37 ng/L; 3个水平的加标回收率为88.8%~108.9%,日内和日间精密度均不大于17.05%。该方法可同时准确、灵敏、简便地测定人尿液中7种邻苯二甲酸酯代谢物的暴露水平。 相似文献
179.
180.
Bushra Asad Taimoor Khan Faiza Zareen Gul Muhammad Asad Ullah Samantha Drouet Sara Mikac Laurine Garros Manon Ferrier Shankhamala Bose Thibaut Munsch Duangjai Tungmunnithum Arnaud Lanoue Nathalie Giglioli-Guivarch Christophe Hano Bilal Haider Abbasi 《Molecules (Basel, Switzerland)》2021,26(15)
In vitro cultures of scarlet flax (Linum grandiflorum L.), an important ornamental flax, have been established as a new possible valuable resource of lignans and neolignans for antioxidant and anti-inflammatory applications. The callogenic potential at different concentrations of α-naphthalene acetic acid (NAA) and thidiazuron (TDZ), alone or in combinations, was evaluated using both L. grandiflorum hypocotyl and cotyledon explants. A higher callus induction frequency was observed on NAA than TDZ, especially for hypocotyl explants, with a maximum frequency (i.e., 95.2%) on 1.0 mg/L of NAA. The presence of NAA (1.0 mg/L) in conjunction with TDZ tended to increase the frequency of callogenesis relative to TDZ alone, but never reached the values observed with NAA alone, thereby indicating the lack of synergy between these two plant growth regulators (PGRs). Similarly, in terms of biomass, NAA was more effective than TDZ, with a maximum accumulation of biomass registered for medium supplemented with 1.0 mg/L of NAA using hypocotyls as initial explants (DW: 13.1 g). However, for biomass, a synergy between the two PGRs was observed, particularly for cotyledon-derived explants and for the lowest concentrations of TDZ. The influence of these two PGRs on callogenesis and biomass is discussed. The HPLC analysis confirmed the presence of lignans (secoisolariciresinol (SECO) and lariciresinol (LARI) and neolignan (dehydrodiconiferyl alcohol [DCA]) naturally accumulated in their glycoside forms. Furthermore, the antioxidant activities performed for both hypocotyl- and cotyledon-derived cultures were also found maximal (DPPH: 89.5%, FRAP 866: µM TEAC, ABTS: 456 µM TEAC) in hypocotyl-derived callus cultures as compared with callus obtained from cotyledon explants. Moreover, the anti-inflammatory activities revealed high inhibition (COX-1: 47.4% and COX-2: 51.1%) for extract of hypocotyl-derived callus cultures at 2.5 mg/L TDZ. The anti-inflammatory action against COX-1 and COX-2 was supported by the IC50 values. This report provides a viable approach for enhanced biomass accumulation and efficient production of (neo)lignans in L. grandiflorum callus cultures. 相似文献