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1.
The purpose of this work is to investigate the effect of the genipin/hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex on the intestinal absorption of genipin and identify its mechanism of action. The phase solubility profile was classified as A(L) type, indicating the formulation of a 1:1 stoichiometry inclusion complex. Fourier transform infrared spectroscopy, Differential scanning calorimetry, X-ray powder diffractometry, and (1)H nuclear magnetic resonance (NMR) and two-dimensional (2D) (1)H rotating-frame Overhauser enhancement (ROESY) NMR spectroscopies further confirmed the formulation of the inclusion complex with superior dissolution properties than the drug alone. The results of single-pass intestinal perfusion showed that the intestinal absorption of genipin was affected by P-glycoprotein (Pgp). The absorption rate and permeability value of the inclusion complex were significantly higher than the free drug, suggesting that its enhancing effect was involved in its solubilizing effect and Pgp inhibitory effect. The mechanisms of HP-β-CD on Pgp inhibition were demonstrated by restraining the Pgp ATPase activity rather than changing the fluidity of the cell membrane. 相似文献
2.
Yufen Huang Zhongzhen Liu Yan He Fang Zeng Ronghui Wang 《Journal of Soils and Sediments》2013,13(1):82-93
Purpose
Adsorption and desorption are important processes that influence the transport, transformation, and bioavailability of atrazine in soils. Equilibrium batch experiments were carried out to investigate the adsorption–desorption characteristics of atrazine. The objectives of this study were to (1) determine and quantify the main soil parameters governing atrazine adsorption and desorption phenomena; (2) find the correlativity between the identified soil parameters; and (3) investigate the universal desorption hysteresis traits.Materials and methods
Fifteen soils with contrasting physico-chemical characteristics were collected from 11 provinces in eastern China. The equilibrium time was 24 h both for adsorption and desorption experiments. Atrazine was detected by Waters 2695/UV HPLC.Results and discussion
Adsorption isotherms of atrazine could be well described by the Freundlich equation (r?≥?0.994, p?<?0.01). The total organic carbon (TOC) was the first independent variable that described 53.0 % of the total variability of K f, followed by the pH (9.9 %), and the clay (4.0 %) and silt (1.2 %) contents, separately; while the primary soil properties that affect desorption parameters included the TOC, pH, free Fe2O3 (Fed) and the sand content, with the biggest contribution achieved by the TOC (ranged from 48.5–78.1 %). The results showed that when the content ratio of clay to TOC (RCO) was less than 40, the atrazine adsorption was largely influenced by the organic matrix, while when the RCO was greater than 40, they were vital affected by the clay content.Conclusions
Adsorption–desorption isotherms of atrazine in soils were nonlinear. The content of TOC, clay, and iron oxides, as well as the pH value were the key soil parameters affecting the adsorption–desorption of atrazine in soil, among which the RCO especially exhibited relevance. Additionally, the desorption hysteresis existed for atrazine retention in all 15 tested soils, and the hysteretic effect enhanced with the increasing time for desorption. This would be ascribed to the heterogeneity physical–chemical properties of these soils. 相似文献3.
《Communications in Soil Science and Plant Analysis》2012,43(7):661-668
Abstract Two contrasting soils were extracted with 0.05 M EDTA in 1 M CH3 COONH4 at pH 6, before and after incubation for 4 weeks at constant (10, 20 or 30°C) or fluctuating (10/30, mean 20°C) temperatures. Less copper was extracted from soils which were incubated at fluctuating temperature than from those maintained at a constant 20 C. Where incubation temperature was constant, extractable copper increased or decreased with increasing temperature depending on the soil and how it was treated. Recovery of added copper was low initially but increased during the incubation. Maximum recovery was associated with low incubation temperature in one soil, but high temperature in the other. The amounts of copper extracted were slightly increased by γ‐irradiation of the soils. Extractable copper was also increased by increasing the temperature at which the extraction was performed. 相似文献
4.
Purpose
Accumulated soil phosphorus (P) in agricultural lands due to long-term organic manure and mineral phosphate fertilizer input is considered one of the main non-point pollution sources to surrounding surface water bodies. A chronosequence of soils is a potent instrument for pedological investigation and allows assessment of the effect of duration of agricultural cultivation on the environmental risk to water bodies of P loss from soil. 相似文献5.
《Communications in Soil Science and Plant Analysis》2012,43(15-16):2547-2563
Abstract Time dependent zinc (Zn) desorption in eight benchmark soils of India was studied in relation to various pH values and ionic strengths. Soil samples were equilibrated in solutions containing 10 μg Zn g‐1 soil at pH 5.5,6.5, and 7.5 for 48 h at 25±2°C, and adsorbed Zn extracted with calcium chloride (CaCl2) for various periods of time. Desorption of Zn decreased with increasing pH, and the desorption rate decreased abruptly at pH 7.5. In contrast, an increase in the equilibration period and ionic strength of the background electrolyte increased Zn desorption. Four rival kinetic models were fitted and evaluated for their suitability for describing the Zn desorption process. Reaction rate constant (ß) calculated from the Elovich model for the different soils ranged from 9.99 to 25 (mg Zn kg‐1)‐1. The different kinetic models tested indicated that Zn desorption in soils was a diffusion controlled process. The desorption was rapid in the first 4 h, followed by slower phase in the rest of the time at all the pH values indicating a biphasic desorption, characteristic of a diffusion controlled process. The ß value for the Elovich equation showed a strong association with soil clay content and cation exchange capacity (CEC). Further, the best prediction of Zn desorption reaction rate constant could be made using multiple‐regression equation with soil clay content and CEC as variables. 相似文献
6.
Temesgen Wakweya Abebe Nigussie Gebeyanesh Worku Armaye Biresaw Abebayheu Aticho Obsu Hirko Gebermedihin Ambaw Melkamu Mamuye Bayu Dume Milkiyas Ahmed 《Soil Use and Management》2022,38(1):703-713
Although the addition of biochar has been shown to reduce the phosphorus (P) adsorption capacity of soil, quantitative evidence of this has mainly been provided by incubation experiments and it is therefore essential to conduct long-term field trials to draw general conclusions. It is largely unknown whether bone char has a greater effect than lignocellulosic biochar on P adsorption–desorption processes and crop yield. The aim of this study was to determine the long-term (8 years) effect of bone char and biochar on P adsorption–desorption and crop yield in low-input acidic soils. The results showed that bone char decreased the maximum P adsorption capacity (Qm) by 10% and increased the desorption capacity (Ds) by 150% compared with the control (i.e. without a soil amendment). The desorption ratio was highest for the bone char treatment (10.3%) and three times more than the control. Plant-available P was seven times greater under bone char than the control. There was no variation in adsorption–desorption characteristics, desorption ratio and plant-P available content between bone char and lignocellulosic biochar treatments. The average yield increment following the application of bone char and biochar was 1.7 and 1.4 Mg ha−1 for maize and 1.8 and 1.9 Mg ha−1 for soya bean, respectively. Despite the low application rate (4 t ha−1 year−1), these findings demonstrated that the long-term application of bone char and biochar-based amendments enhanced P availability in low-input cropping systems, mainly by altering the P adsorption and desorption capacity of soils. 相似文献
7.
《Communications in Soil Science and Plant Analysis》2012,43(5-6):671-680
Abstract The parameters obtained from the quantity‐intensity (Q/I) isotherms have been used by several authors as criteria to estimate the immediate availability of labile potassium (K) in a soil. The aim of this work was to study how these parameters have been modified in four agricultural soils in Argentina by the addition of K (0 to 936 kg K2O ha‐1) in an incubation trial simulating K fertilizers application. In two of the soils, the increase in the labile forms of K was proportional to the amount of added K and the recovery percentages were high. In the other soils, a contrasting behavior was found. This difference might be due to different fixing capacity of the soils, which was related to the clay content and mineralogical composition of this fraction. The slopes of the Q/I curves for each soil indicate that the potential buffer capacity (PBC) was similar for the different treatments over the range of K added. The addition of K produced proportional increases in ARe and ?Ko values. This could be attributed to the presence of non saturated planar sites at the highest rates of K applied. 相似文献
8.
《Communications in Soil Science and Plant Analysis》2012,43(3):193-202
Abstract The study reported herein was intended to determine the effect of (i) wet‐incubation and subsequent air‐drying, and (ii) oven‐drying on DTPA‐Fe, Zn, Mn, and Cu. Analysis of wet‐incubated soils showed significant decreases in DTPA‐Fe, Mn, and Cu at the 1% and Zn at the 10% level of probability. Air‐drying of these moist‐incubated soils increased the levels of Fe, Zn, and Cu to values close to their original levels. Levels of Mn sharply deviated from their original values after air‐drying of incubated soils. Correlation coefficients (r) between the amounts of extractable nutrients in original air‐dry soils and wet‐incubated soils were 0.54, 0.87, 0.91, and 0.13 for Fe, Zn, Cu, and Mn, respectively. Oven‐drying increased the levels of DTPA‐extractable micronutrients from 2 to 6 fold. 相似文献
9.
Mahdi Najafi Ghiri Mahrooz Rezaei Abdolmajid Sameni 《Archives of Agronomy and Soil Science》2013,59(9):945-957
Zinc sorption–desorption by sand, silt and clay fractions of six representative calcareous soils of Iran were measured. Sand, silt and clay particles were fractionated after dispersion of soils with an ultrasonic probe. Zinc sorption analysis was performed by adding eight rates of Zn from 6 to 120 μmol g?1. For the desorption experiment, samples retained after the measurement of Zn sorption were resuspended sequentially in 0.01 M NaNO3 solution and shaken for 24 h. Results indicated that Zn sorption by soil fractions increased in the order clay > silt > sand, and correlated negatively with CaCO3 content and positively with cation exchange capacity (CEC) and smectite content. Results indicated that for all fractions, the Langmuir equation described the sorption rates fairly well. In contrast to sorption, Zn desorption from soil fractions increased in the order sand > silt > clay, and correlated positively with CaCO3 content, CEC and smectite content. Results showed that parabolic diffusion and two constant equations adequately described the reaction rates of Zn desorption. In general, for all soils studied, the coarser the particle size, the less Zn sorption and more Zn desorption, and this reflects much higher risk of Zn leaching into groundwater or plant uptake in contaminated soils. 相似文献
10.
A. Yilmaz H. Ekiz I. Gültekin B. Torun H. Barut S. Karanlik 《Journal of plant nutrition》2013,36(10):2257-2264
Field experiments were carried out to study the effect of different seed‐zinc (Zn) content on grain yield and grain Zn concentration in a bread wheat cultivar Atay 85 grown in a severely Zn‐deficient soil under rainfed and irrigated conditions for two years. Three groups of seeds with Zn contents of 355, 800, and 1,465 ng Zn seed‐1 were obtained through different number of foliar applications of ZnSO4.7H2O in the previous crop year. Experiments were carried out with 23 kg Zn ha‐1 (as ZnSO4.7H2O) and without Zn fertilization to the soil. Grain yield from seeds with 800 and 1,465 ng Zn seed‐1 content was significantly higher than that from low seed‐Zn, especially under rainfed conditions. In the first year, under rainfed and Zn‐deficient conditions, yield of plants grown from the highest seed‐Zn content was 116% higher than the yield of plants grown from the low seed‐Zn content. However, in the first year soil‐Zn application combined with low‐Zn seed resulted in a yield increase of 466% compared to nill Zn treatment with low‐Zn seed, indicating that higher seed‐Zn contents could not compensate for the effects of soil Zn application. Soil Zn application significantly increased Zn concentrations in shoot and grain. However, the effect of different seed Zn contents on Zn concentrations of plants was not significant, probably due to the dilution of Zn in tissues resulting from enhanced dry matter production. The results presented show that wheat plants grown from seed with high Zn content can achieve higher grain yields than those grown from the low‐Zn seed when Zn was not applied to the soil. Therefore, sowing seeds with higher Zn contents can be considered a practical solution to alleviate Zn deficiency problem, especially under rainfed conditions in spite of it being insufficient to completely overcome the problem. 相似文献
11.
《Communications in Soil Science and Plant Analysis》2012,43(1-2):23-45
Abstract Effect of two moisture levels (22.5 and 13.5%, w/w) and wetting‐drying cycles on manganese solubility was studied in NaCl‐amended soil. During 6 d incubation, higher moisture level released 40‐fold more water‐soluble Mn and 60‐fold more NH4OAc‐exchangeable‐Mn in non‐salinized soil. In NaCl‐treated soil, 50 to over 200% greater soluble and exchangeable Mn was recovered from samples incubated at 22.5% compared to 13.5% water levels. Wetting‐drying cycles significantly (P≤0.05) decreased water‐soluble Mn, which accounted for 50 to 60% increases in the exchange‐able Mn. Since other non‐oxidizing/reducing cations (Ca, Mg, Na, K) also demonstrated similar behavior, it is proposed that in addition to oxidation upon drying and reduction upon wetting, the increases in exchangeable Mn and simultaneous decreases in soluble Mn concentration are due to sorption processes. These results suggest that under field conditions, the insolubility of Mn due to continued wetting‐drying cycles may eventually lead to Mn deficiency in soils low in Mn. 相似文献
12.
A. Yilmaz H. Ekiz B. Torun I. Gultekin S. Karanlik S. A. Bagci 《Journal of plant nutrition》2013,36(4-5):461-471
The effect of six different zinc (Zn) application methods on grain yield and concentrations of Zn in whole shoots and grain was studied in wheat cultivars (Triticum aestivum, L. cvs. Gerek‐79, Dagdas‐94 and Bezostaja‐1 and Triticum durum, Desf. cv. Kunduru‐1149) grown on severely Zn‐deficient calcareous soils (DTPA‐extractable Zn: 0.12 mg‐kg‐1 soil) of Central Anatolia which is the major wheat growing area of Turkey. Zinc application methods tested were: a) control (no Zn application), b) soil, c) seed, d) leaf, e) soil+leaf, and f) seed+leaf applications. Irrespective of the method, application of Zn significantly increased grain yield in all cultivars. Compared to the control, increases in grain yield were about 260% with soil, soil+leaf, and seed+leaf, 204% with seed and 124% with leaf application of Zn. In a similar manner, biomass production (dry weight of above‐ground parts) was increased by Zn treatments. The highest increase (109%) was obtained with the soil application and the lowest increase (40%) with the leaf application. Significant effects of Zn application methods were also found on the yield components, i.e., spike number.m‐2, grain number‐spike‐1, and thousand kernel weight. Spike number.m‐2 was affected most by Zn applications, particularly by soil and soil+leaf applications. Concentrations of Zn in whole shoots and grain were greatly affected by different Zn treatments. In plants without added Zn, concentrations of Zn were about 10 mg‐kg‐1 both in shoots and grain and increased to 18 mg‐kg‐1 dry weight (DW) by soil application of Zn, but not affected by seed application of Zn. Soil+leaf application of Zn had the highest increase in concentration of Zn in shoot (82 mg‐kg‐1 DW) and grain (38 mg‐kg‐1 DW). Soil application of Zn was economical and had long‐term effects for enhancing grain yield of wheat grown on Zn deficient soils. When high grain yield and high Zn concentration in grains are desired, soil+leaf application of Zn was most effective method of Zn application. 相似文献
13.
《Communications in Soil Science and Plant Analysis》2012,43(4):277-286
Abstract Few references explain the effects of dry‐heat sterilization on soil chemical properties. Yet dry heating at 121°C for 2 hours is the prescribed USDA Animal, Plant, and Health Inspection Service basic treatment for soils entering United States ports of entry. This study concerns the effects of air drying and dryheat sterilization on chemical properties of Puerto Rican soils, chiefly macronutrients and micronutrients, found after extracting with Mehlich‐1 and Olsen solutions. Results for dry heating are compared with reported results for other sterilization procedures. Dry heating did not significantly alter soil N, organic matter content, or soil bases. Depending on the extractant used, changes in P concentrations were significant. Results for micronutrient determinations were more variable and also depended on the extractant used after sterilization. Concentrations of Mn and Fe extracted from dry‐heated soils were significantly greater than concentrations extracted from air‐dried soils. Effects of dry‐heat sterilization on soil chemical properties generally followed results published elsewhere for steaming, exceptions depending on the extractant used. Published results from chemical sterilization established methylbromide as being closest to dry heat results. 相似文献
14.
《Communications in Soil Science and Plant Analysis》2012,43(3):613-622
Abstract To determine the effect of incubation on DTPA‐extractable Fe, Zn, and Cu in soils with a wide pH range (4.2 ‐ 9.4) and to determine the nature of this effect, soils were incubated at field moisture capacity for 1 week with and without a sterilant (toluene). After incubation these soils as well as their air‐dry counterparts were analyzed for DTPA‐extractable Fe, Zn, and Cu. Incubated soils were significantly lower in DTPA‐extractable Fe, Zn, and Cu than air‐dry soils over all soil pH values tested but there was no significant difference in mean values for incubated soils due to the addition of toluene. The results suggest that, upon incubation at field moisture capacity, the decrease in DTPA‐extractable Fe, Zn, and Cu observed was noa‐microbial in nature. 相似文献
15.
R. F. Brennan 《Journal of plant nutrition》2013,36(2):349-358
Five field experiments are described which measured the effect of three sources of nitrogen (N) fertilizer, applied at 45 kg N/ha, on the incidence of take‐all and grain yield of wheat. The N fertilizers were ammonium sulphate, ammonium chloride, and sodium nitrate. Compared with the Nil N treatment, ammonium‐nitrogen fertilizer, either as ammonium sulphate (ASdr) or ammonium chloride (ACdr) drilled with the seed, lowered the severity of take‐all. Sodium nitrate topdressed (SNtd) to the soil surface reduced the severity of take‐all in three of five experiments, while ammonium sulphate topdressed (Astd) reduced the severity in four of the five experiments. Ammonium sulphate and ammonium chloride drilled with the seed were equally effective in reducing the severity of take‐all in three of the five experiments. However, ACdr was more effective than ASdr in reducing the severity of take‐all in one experiment whereas ASdr was more effective than ACdr in another experiment. In these two experiments (1 and 5), the effects of the reduction in take‐all severity between the ASdr and ACdr treatments did not affect grain yield. The results suggest that grain yield losses from take‐all are most severe where wheat plants are deficient in N. Chloride containing fertilizers are unlikely to control take‐all disease of wheat on soils of southwestern Australia. 相似文献
16.
Braekevelt E Lau BP Tague B Popovic S Tittlemier SA 《Journal of agricultural and food chemistry》2011,59(3):915-920
Because beef food products are generally cooked prior to consumption, the behavior of chemicals in these cooked foods is important in estimating human exposure. The heat stability of the natural estrogen β-estradiol (β-E2) and its metabolites α-estradiol (α-E2), estrone (E1), and several catechol estrogens was examined in heated vegetable oil and aqueous solutions. The chemicals were also incorporated into regular and extra lean ground beef and subjected to cooking. E1 and E2 were stable in aqueous solutions at 100°C, whereas the catechol estrogens exhibited first-order decay curves with half-lives of 2-10 min. Their stability improved to the same level as the other test chemicals when an antioxidant was added to the solution, suggesting that their disappearance was due to oxidation rather than thermal degradation. E1 and E2 were also stable in heated vegetable oil (160-180°C), whereas catechol estrogen decreased 30-50% over the 2 h duration of the experiments. Chemical losses from cooked beef appear to be related to the fat content of the beef, with greater losses occurring in regular ground beef (25-30%), compared to extra lean ground beef (5-20%). This study shows that cooking reduces but does not eliminate the potential for dietary exposure to growth promoters in ground beef. 相似文献
17.
Purpose
Organic dyes have been turned into an important emerging type of chemical pollutants with the development of rural textiles, synthetic dye, printing, and dyeing industries and the continuous release from washing fabrics and clothes in recent decades. In order to assess ecological risk of reactive X-3B red dye as a typical dye, the adsorptive and desorptive traits of the dye in soils were investigated and the environmental factors influencing those processes were examined and discussed. 相似文献18.
Pinus radiata seedlings were inoculated with basidiospores of Rhizopogon roseolas and Suillus granulatus, and with chlamylospores of two unidentified but highly effective mycorrhizal fungi in undisturbed cores of natural soil fumigated with methyl bromide. Fumigation stimulated mycorrhizal infection rate and enhanced the response of seedlings to increasing concentrations of both inoculum types, but the effect of chlamydospore inoculum was more favoured by fumigation than that of basidio-spores. Chlamydospore inocula appear more sensitive to competitive and antagonistic soil microorganisms than basidiospores. Soil fumigation appears a necessary adjunct to the use of chlamydospores as inoculants in nurseries and is discussed in relation to nursery culture of pines. 相似文献
19.
Foliar nutrient concentrations vary during the day. Field research was conducted to quantify and better understand this variation in corn (Zea mays L.) and soybean (Glycine max L. Merr.) with foliar sampling during the vegetative and reproductive stages. Time of day effects occurred inconsistently across nutrients. Nitrogen (N), manganese (Mn), iron (Fe), and zinc (Zn) foliar concentrations were generally high early in the day. Phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S) foliar concentrations varied inconsistently with time of day, while concentrations of boron (B) in both crops and copper (Cu) in corn were not affected. Limiting foliar sampling to after 10:00 AM reduced the variation for soybean but not for corn. Interpretation by Diagnosis and Recommendation Integrated System (DRIS) did not reduce the time of day effect. The variation caused by time of day, along with other causes, affects confidence in interpretation of foliar results suggesting use of the information with either additional foliar sampling or soil testing in making nutrient management decisions. 相似文献
20.
《Communications in Soil Science and Plant Analysis》2012,43(13-14):2247-2259
Abstract Blackgram (Vigna mungo L.) plants were grown in glasshouse earthen pot experiment. Zinc (Zn) was applied to the soil at different concentrtions. Plant leaf samples were analysed at the age of 30, 45, and 65 days after sowing. The accumulation of Zn in the plant increased with the applied Zn concentration to the soil. Also a variation in the uptake of Zn by the plant with age has been observed. The excess accumulation of Zn in the plant induced a reduction in the content of some macro‐ [calcium (Ca), magnesium (Mg), potassium (K), and sodium (Na)] and micro‐elements [iron (Fe), manganese (Mn), and copper (Cu)] in the plant leaves. Furthermore, the Ca: Zn ratio decreased with increasing Zn concentration which clearly indicates a toxic Zn effect on blackgram plants. 相似文献