A rapid method for the determination of chlorine, phosphorus, and sulfur in flours of grains and legumes using wavelength dispersive x-ray flourescence spectrometry     

T Pérez Ruiz  M Hernández Córdoba  R González 《Journal of the Association of Official Analytical Chemists》1991,74(4):625-626

A rapid method for the determination of chlorine, phosphorus, and sulfur in commercial flours of wheat, barley, maize, rice, field bean, and soybean by wavelength dispersive x-ray fluorescence spectrometry has been developed. The flours are strained through a 425 microns sieve, then pelletized and measured. The total analysis time for the quantitation of chlorine, phosphorus, and sulfur is less than 20 min per sample. Calibration is carried out using a standard additions method with mixed standards. The method is accurate and precise, and appears to be adequate for routine analyses.  相似文献   

Molecular tracing of <Emphasis Type="Italic">Bradyrhizobium </Emphasis>strains helps to correctly interpret <Emphasis Type="Italic">Acacia mangium </Emphasis>response to inoculation in a reforestation experiment in Madagascar     

Y.?PrinEmail author  A.?Galiana  C.?Le Roux  B.?Méléard  V.?Razafimaharo  M.?Ducousso  G.?Chaix 《Biology and Fertility of Soils》2003,37(1):64-69

A field inoculation experiment using two Bradyrhizobium sp. strains was set up in Madagascar to test the growth response of Acacia mangium and to follow up the survival of inoculant strains using molecular tools. Three months after inoculation, one of the inoculant strains, AUST13c, exhibited a marked growth-promoting effect with a shoot height about 40% higher than that of the uninoculated control plants or TEL8-inoculated plants. The positive effect on tree growth initially observed with AUST13c was no more significant 6 months after transfer to the field and disappeared completely at 13 and 19 months. Analyses of nodule bacterial rRNA by PCR/RFLP displayed an early contamination of the different inoculation treatments by AUST13c 3 months after inoculation, spreading to almost all nodules of the trial 6 months later. This work clearly demonstrated that the progressive reduction of the positive effect of AUST13c inoculation on tree growth after field transplanting was not due to a progressive disappearance of this introduced strain but, on the contrary, was related to the widening spreading of AUST13c in all the plots. This was attributed to a higher competitiveness and effectiveness of AUST13c over the local strains and TEL8.  相似文献   

Removal of Copper and Cadmium Ions from Diluted Aqueous Solutions by Low Cost and Waste Material Adsorbents   总被引：2，自引：0，他引：2  

Ulmanu  Mihaela  Marañón  Elena  Fernández  Yolanda  Castrillón  Leonor  Anger  Ildiko  Dumitriu  Daniela 《Water, air, and soil pollution》2003,142(1-4):357-373

The sorption of copper and cadmium ions using activated carbon,kaolin, bentonite, diatomite and waste materials such as compost,cellulose pulp waste and anaerobic sludge as sorbents is reported. Equilibrium isotherms were obtained for the adsorption of these metals in single and binary solutions. Bentonite presented the highest adsorption capacities for both copper and cadmium. A competitive uptake was observed when both metals are present; copper being preferentially adsorbed by all materials with theexception of anaerobic sludge. Equilibrium data were fitted toLangmuir and Freundlich models, with satisfactory results for most of the adsorbent-metal systems studied.Of all the adsorbents studied, bentonite and compost presentedthe highest removal efficiencies, reaching 99% for copper whencadmium is also present, for initial solution concentrations ofup to 100 mg L^-1. Anaerobic sludge has a greater preferencefor cadmium, even in the presence of copper, with removal efficiencies of 98% for similar concentrations to those mentioned above.  相似文献   

Effect of cooking temperatures on chemical changes in species of organic arsenic in seafood   总被引：2，自引：0，他引：2  

Devesa V  Martínez A  Súñer MA  Vélez D  Almela C  Montoro R 《Journal of agricultural and food chemistry》2001,49(5):2272-2276

The concentrations of arsenobetaine (AB), tetramethylarsonium ion (TMA(+)), and trimethylarsine oxide (TMAO) were determined in samples of sole, dory, hake, and sardine, raw and after being subjected to cooking processes--baking, frying, and grilling--at various temperatures. In all cases, the temperature attained inside the product during the cooking process was measured. The arsenic species extracted from the samples with methanol/water were separated by means of a column switching technique between a PRP-X100 column and a PRP-X200 column. AB was detected by hydride generation atomic absorption spectrometry, whereas TMA(+) and TMAO were detected by hydride generation atomic fluorescence spectrometry. The results obtained showed that, in all of the types of seafood studied, TMA(+) appeared after cooking, possibly because heating facilitates decarboxylation of AB to TMA(+).  相似文献   

Taste active compounds in a goat cheese water-soluble extract. 1. Development and sensory validation of a model water-soluble extract     

Engel E  Nicklaus S  Garem A  Septier C  Salles C  Le Quéré JL 《Journal of agricultural and food chemistry》2000,48(9):4252-4259

The aim of this study was to evaluate the impact of the components of a goat cheese water-soluble extract (WSE) on its flavor by both physicochemical and sensory techniques with special emphasis on taste. After characterization of the organoleptic properties of the cheese, the WSE was extracted with pure water and submitted to successive tangential ultrafiltrations and nanofiltration. The physicochemical assessment of these fractions led to the constitution of a model mixture (MWSE) compared by sensory evaluation to the crude WSE, using a panel of 16 trained members. The results of both sensory profile and triangular tests indicate no significant difference, therefore proving that the reconstitution of the WSE was correct, thereby showing the sensory neutrality of lipids and peptides smaller than 500 Da, which had not been included in the MWSE. Moreover, the cheese gustatory characteristics are comparable to those of the WSE despite weaker levels of sharpness and astringency in the extract, the respective origins of which are discussed.  相似文献   

Total and inorganic arsenic in fresh and processed fish products     

Muñoz O  Devesa V  Suñer MA  Vélez D  Montoro R  Urieta I  Macho ML  Jalón M 《Journal of agricultural and food chemistry》2000,48(9):4369-4376

Total arsenic and inorganic arsenic contents were determined in 153 samples of seafood products consumed in the Basque Country (Spain): fish (white fish and blue fish), mollusks, crustaceans, and preserved fish. White fish presented higher levels of total arsenic and lower levels of inorganic arsenic than the blue fish, indicating possible differences in the metabolization of inorganic arsenic. For total arsenic, 66% of the samples exceeded the maximum permitted level by the strictest international legislation in seafood products [1 microg g(-)(1), wet weight (ww)]. The levels of inorganic arsenic were considerably lower than the maximum authorized in New Zealand (2 microg g(-)(1), ww), the only country with legislation for inorganic arsenic in fish and fish products. It is recommended that legislation based on levels of inorganic arsenic should be established.  相似文献   

Element distribution of some soils of continental Chile and the Antarctic peninsula. Projection to atmospheric pollution     

Adriana Carrasco  M.  Préndez  Margarita 《Water, air, and soil pollution》1991,57(1):713-722

Water, Air, & Soil Pollution - The elemental content of some soils of continental Chile and the Antarctic Peninsula are reported. The elements: Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb were...  相似文献   

Management of human health risk in the context of kitchen gardens polluted by lead and cadmium near a lead recycling company     

Stéphane Mombo  Yann Foucault  Frédéric Deola  Irène Gaillard  Sylvaine Goix  Muhammad Shahid  Eva Schreck  Antoine Pierart  Camille Dumat 《Journal of Soils and Sediments》2016,16(4):1214-1224

  相似文献   

Effect of the addition of sewage sludge as a fertilizer on a sandy vineyard soil     

Bravo-Martín-Consuegra  Sandra  García-Navarro  Francisco Jesús  Amorós-Ortíz-Villajos  José Ángel  Pérez-de-los-Reyes  Caridad  Higueras  Pablo L. 《Journal of Soils and Sediments》2016,16(4):1360-1365

Purpose

The application of sludge from wastewater in agriculture has increased in recent years, and it is therefore important to assess the effect that such treatment has on both the soil and the plant. The aim of the study described here was to ascertain whether there is a variation in the properties of the soil and to determine if this addition has an impact on the plant.

Materials and methods

The area of investigation was close to the municipality of Villarrubia de los Ojos (Ciudad Real). In this work, six samples were taken from the surface horizon in the studied plot at a depth of 35 cm. A further three samples were taken: (i) a surface horizon of a soil close to the area under investigation but without treatment (control sample), (ii) a sample of sludge from the wastewater treatment plant and (iii) a sample of the mixture used by farmers as fertilizer. Laboratory tests were conducted in accordance with the SCS-USDA (1972) guidelines. Trace element samples were analysed by X-ray fluorescence spectrophotometry (Philips PW 2404).

Results and discussion

The parcel of land studied is dominated by a sandy texture (88.3 % sand), and a decrease in pH was observed in areas in which the mixture (manure + sludge) was added (pH?=?8.0) compared to areas in which fertilizer was not applied (pH?=?8.5). It was observed that the addition of the compound led to an increase in the electrical conductivity of the soil. The trace elements can be organized into two groups based on the results obtained in this study. One group contains the trace elements that were only present in the rows that were treated with the fertilizer. The other group of trace elements was mobilized throughout the whole plot.

Conclusions

The application of sewage sludge on agricultural soils can be very useful as an organic amendment because it produces an increase in soil organic matter. However, sewage sludge must be applied with caution due to the changes in soil chemical properties (for example, pH and E.C.). The use of this type of waste for prolonged periods of time can cause problems of contamination in the soil.

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Fresh Israeli Jaffa blond (Shamouti) orange and Israeli Jaffa red Star Ruby (Sunrise) grapefruit juices affect plasma lipid metabolism and antioxidant capacity in rats fed added cholesterol   总被引：2，自引：0，他引：2  

Gorinstein S  Leontowicz H  Leontowicz M  Krzeminski R  Gralak M  Martin-Belloso O  Delgado-Licon E  Haruenkit R  Katrich E  Park YS  Jung ST  Trakhtenberg S 《Journal of agricultural and food chemistry》2004,52(15):4853-4859

The bioactivity of Israeli Jaffa blond (Shamouti) fresh orange and Israeli Jaffa red Star Ruby (Sunrise) grapefruit juices was investigated in vitro and in vivo. The contents of bioactive compounds of these juices were determined. The influence of bioactive compounds on plasma lipids and plasma antioxidant activity in rats fed cholesterol-containing and cholesterol-free diets was assessed. Significant differences in the contents of dietary fibers were not found. The contents of total polyphenols, flavonoids, and anthocyanins in fresh orange and grapefruit juices were 962.1 +/- 27.2 and 906.9 +/- 27.1; 50.1 +/- 3.3 and 44.8 +/- 3.2; and 69.9 +/- 5.6 and 68.7 +/- 5.5 microg/mL, respectively. The antioxidant potential measured by the scavenging activity against nitric oxide, the beta-carotene-linoleate model system (beta-carotene), and the 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis(3-ethyl-benzothiazoline-6-sulfonic acid) diamonium salt assays was higher in orange juice but not significantly. A high level of correlation between contents of total polyphenols and flavonoids and antioxidant potential values of both juices was found. Diets supplemented with orange and to a lesser degree with grapefruit juices improved plasma lipid metabolism only in rats fed added cholesterol. However, an increase in the plasma antioxidant activity was observed in both groups. In conclusion, fresh orange and grapefruit juices contain high quantities of bioactive compounds, which guarantee their high antioxidant potential, and the positive influence on plasma lipid metabolism and plasma antioxidant activity could make fresh orange and grapefruit juices a valuable supplement for disease-preventing diets.  相似文献