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1.
J Equine Vet Sci ; 132: 104975, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38040068

RESUMEN

Foals require maternal colostrum in the first hours of life to prevent failure of transfer of passive immunity (FTIP). Innovative storage methods such as lyophilization may enable conservation of colostrum immunoglobulins by a differentiated process of dehydration. The current study aimed to compare the quality of equine colostrum after freezing and after the lyophilization process. Thirty-one pregnant Quarter Horse mares were used. The IgG concentration of frozen and lyophilized colostrum was determined by simple radial immunodiffusion (SRID) and Brix refractometry. The physical-chemical composition (pH, total protein (TP), fat, lactose, salts, total solids (TS), and density) of the samples was evaluated and the lyophilized colostrum reconstitution test was performed. There were no significant differences (P > 0.05) in the variables IgG, fat, lactose, salts, TS, density, and pH between samples measured before and after lyophilization. There was a significant difference (P < 0.05) between the Brix average and the TP of the frozen and lyophilized colostrum samples. Lyophilization resulted in a small reduction (6.55%) in the IgG concentration measured by SRID. A strong positive correlation was observed between colostrum density and IgG concentration by SRID (r = 0.76) and between Brix and IgG concentration by SRID (r = 0.77). In the reconstitution test, the lyophilized colostrum was easily rehydrated in water, with full dilution, and remained stable. Lyophilization could be an alternative for the conservation of mare colostrum, since it is a very efficient process for retaining the physicochemical characteristics of the product, with minimal loss, particularly of IgG.


Asunto(s)
Calostro , Lactosa , Embarazo , Animales , Caballos , Femenino , Lactosa/análisis , Sales (Química)/análisis , Inmunoglobulina G/análisis , Refractometría/veterinaria
2.
Molecules ; 27(24)2022 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-36558134

RESUMEN

Pinus radiata bark is a rich source of polyphenols, which are mainly composed of proanthocyanidins. This study aimed to utilize P. radiata bark as a polyol source for bio-foam production in the future. Polyphenol-rich alkaline extracts (AEs) from P. radiata bark were prepared by mild alkaline treatment and then derivatized with propylene oxide (PO). Hydroxypropylated alkaline extracts (HAEs) with varying molar substitutions (MS 0.4-8.0) were characterized by FT-IR, NMR, GPC, TGA, and DSC. The hydroxyl value and solubility in commercial polyols were also determined. The molecular weights of the acetylated HAEs (Ac-HAEs) were found to be 4000 to 4900 Da. Analyses of FT-IR of HAEs and 1H NMR of Ac-HAEs indicated that the aromatic hydroxyl groups were hydroxypropylated and showed an increase in aliphatic hydroxyl group content. The glass transition temperature (Tg) of AE and HAEs were 58 to 60 °C, showing little difference. The hydroxyl value increased as the hydroxypropylation proceeded. Although salts were produced upon neutralization after hydroxypropylation, HAEs still showed suitable solubility in polyether and polyester polyols; HAEs dissolved well in polyether polyol, PEG#400, and solubility reached about 50% (w/w). This indicated that neutralized HAEs could be directly applied to bio-foam production even without removing salts.


Asunto(s)
Pinus , Polifenoles , Polifenoles/análisis , Pinus/química , Corteza de la Planta/química , Espectroscopía Infrarroja por Transformada de Fourier , Sales (Química)/análisis , Extractos Vegetales/química
3.
J Food Biochem ; 46(10): e14266, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35652286

RESUMEN

Hot water treatment (HT) induces chilling injury (CI) tolerance in mango, but prolonged exposure to HT causes softening. In this sense, calcium salts stabilize the cell wall. Nevertheless, there is little information on the effect of HT combined with calcium salts (HT-Ca) on calcium absorption and cell wall stability during storage of mango at CI temperature. We evaluated the effect of quarantine HT in combination with calcium chloride (CaCl2 ), calcium citrate (CaCit), or calcium lactate (CaLac) on calcium absorption, CI tolerance, and cell wall stabilization. HT and HT-CaCl2 had the lowest CI development. HT increased firmness loss and electrolyte leakage, and HT-Ca counteracted this effect. Overall, HT-Ca treatments had a similar effect on the cell wall degrading enzymes. HT-CaCl2 was the best treatment and did not present alterations on the epicuticular wax as observed on HT. HT-CaCl2 is a useful technology to stabilize cell wall and preserve mango during chilling storage. PRACTICAL APPLICATIONS: The addition of calcium salts in an established hot water quarantine procedure for mango exportation represents a viable alternative to counteract the negative effects of this thermal treatment upon cell microstructure, maintaining its positive effect of tolerance to chilling injury. In this sense, mango producers and packers can use a HT-CaCl2 treatment to reduce the presence of chilling injury and extent the fruit shelf life and improve its commercialization. Furthermore, technical and infrastructure changes are not necessary for the packaging chain.


Asunto(s)
Mangifera , Purificación del Agua , Calcio , Cloruro de Calcio/análisis , Cloruro de Calcio/farmacología , Citrato de Calcio/análisis , Citrato de Calcio/farmacología , Pared Celular , Frío , Frutas/química , Mangifera/química , Cuarentena , Sales (Química)/análisis , Sales (Química)/farmacología , Temperatura
4.
Molecules ; 27(4)2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35209114

RESUMEN

In this work, a flow-based spectrofluorimetric method for iodine determination was developed. The system consisted of a miniaturized chip-based flow manifold for solutions handling and with integrated spectrofluorimetric detection. A multi-syringe module was used as a liquid driver. Iodide was quantified from its catalytic effect on the redox reaction between Ce(IV) and As(III), based on the Sandell-Kolthoff reaction. The method was applied for the determination of iodine in salt, pharmaceuticals, supplement pills, and seaweed samples without off-line pre-treatment. An in-line oxidation process, aided by UV radiation, was implemented to analyse some samples (supplement pills and seaweed samples) to eliminate interferences and release iodine from organo-iodine compounds. This feature, combined with the fluorometric reaction, makes this method simpler, faster, and more sensitive than the classic approach of the Sandell-Kolthoff reaction. The method allowed iodine to be determined within a range of 0.20-4.0 µmol L-1, with or without the in-line UV digestion, with a limit of detection of 0.028 µmol L-1 and 0.025 µmol L-1, respectively.


Asunto(s)
Yodo/análisis , Preparaciones Farmacéuticas/análisis , Sales (Química)/análisis , Espectrometría de Fluorescencia/instrumentación , Espectrometría de Fluorescencia/métodos , Digestión , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Fluorescencia/normas , Jeringas
5.
Food Res Int ; 136: 109608, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32846628

RESUMEN

Spices, herbs, and seasoning blends containing both crystalline and amorphous ingredients are common throughout the food industry but may exhibit unwanted clumping or caking during storage. Crystalline and amorphous ingredients are known to respond differently to increases in relative humidity (RH) and temperature. The aim of this study was to better characterize what happens to moisture sorption behaviors, water-solid interactions, and physical stability when crystalline and amorphous ingredients are co-formulated in seasoning blends. Spices, herbs, and seasoning blends, 25 in total, were studied individually and in blends of increasing complexity (binary, ternary, and quaternary) with sucrose, salt, and maltodextrin. The effects of increasing temperature and RH on moisture content, moisture sorption profiles, water activity (aw), glass transition temperature (Tg), including Gordon-Taylor modeling, physical appearance, and degree of clumping were measured. Crossover points, the temperature at which the aw of the amorphous ingredient(s) and the deliquescence RH of the crystalline ingredient(s) in a blend intersect, were also calculated. Caking was observed when storage conditions (RH and/or temperature) exceeded the Tg of a blend or the deliquescence RH of a crystalline ingredient in the blend. When amorphous and crystalline ingredients were blended, synergistic moisture sorption and increased caking was observed. When multiple crystalline ingredients were present, mutual deliquescence further increased the sensitivity of the blend to moisture. When environmental conditions exceeded the crossover temperature, degree of caking increased, and physical appearance was altered due to the induced deliquescence of the crystalline ingredient(s) by the aw of the amorphous ingredient(s). In general, as complexity of blends increased, sensitivity to moisture also increased, and physical stability of the blends decreased. The results of this study provide valuable information for increasing the physical stability of complex seasoning blends based on moisture sorption behaviors.


Asunto(s)
Especias/análisis , Temperatura , Agua/análisis , Almacenamiento de Alimentos , Cebollas/química , Polisacáridos/análisis , Polvos/química , Sales (Química)/análisis , Sacarosa/análisis , Temperatura de Transición , Compuestos Orgánicos Volátiles/análisis
6.
J Food Sci ; 82(12): 2987-2996, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29125622

RESUMEN

Reformulation of calcium chloride (CaCl2 ) cover brine for cucumber fermentation was explored as a mean to minimize the incidence of bloater defect. This study particularly focused on cover brine supplementation with calcium hydroxide (Ca[OH]2 ), sodium chloride (NaCl), and acids to enhance buffer capacity, inhibit the indigenous carbon dioxide (CO2 )- producing microbiota, and decrease the solubility of the gas. The influence of the cover brine formulations tested, on the cucumber fermentation microbiota, biochemistry, CO2 production, and bloating defect was studied using metagenetics, HPLC analysis, a portable gas analyzer and bloater index, respectively. Cover brine supplementation with Ca(OH)2 and acetic acid resulted in complete fermentations with final pH values 0.5 units higher than the un-supplemented control. Lactic acid production increased by approximately 22%, possibly inducing the observed reduction in the relative abundance of Enterobacteriaceae by 92%. Ca(OH)2 supplementation also resulted in an increased relative abundance of Leuconostocaceae by 7%, which likely contributed to the observed increment in CO2 levels by 25%. A 50% reduction on acetic acid formation was detected when cover brines were supplemented with Ca(OH)2 and 690 mM (4%) NaCl. No significant difference was observed in bloater index as the result of Ca(OH)2 or NaCl supplementation in cover brines, given that the CO2 levels remained at above the 20 mg/100 mL needed to induce the defect. It is concluded that the modified cover brine formulation containing Ca(OH)2 and NaCl enables the complete conversion of sugars, decreases production of CO2 and levels of Enterobacteriaceae, but insignificantly reduces bloater index. PRACTICAL APPLICATION: A cucumber fermentation cover brine containing Ca(OH)2 , 0.26% CaCl2 , 345 mM (2%) NaCl, and acetic acid to pH 4.7 has a functional combination of ingredients enabling a complete conversion of sugars to lactic acid with reduced production of acetic acid and CO2 . It represents a process ready cover brine formulation with the potential to allow the manufacture of cucumber pickles with low salt, enhanced food safety, and reduce environmental impact and water usage. Pilot commercial scale cucumber fermentations brined with such ingredients are to reveal the efficacy of this process ready formulation in the presence of oxygen from air in tanks, as opposed to 3.8 L (1-US gal) closed jars in the laboratory.


Asunto(s)
Cucumis sativus/química , Conservación de Alimentos/métodos , Ácido Acético/análisis , Cloruro de Calcio/análisis , Fermentación , Concentración de Iones de Hidrógeno , Ácido Láctico/análisis , Sales (Química)/análisis , Cloruro de Sodio/análisis
7.
Chemosphere ; 165: 202-210, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27654223

RESUMEN

Phosphorus (P) recovery from waste streams has recently been recognized as a key step in the sustainable supply of this indispensable and non-renewable resource. The feasibility of using brine from a reverse osmosis (RO) membrane unit treating cooling water as a precipitant for P recovery from source separated urine was evaluated in the present study. P removal efficiency, process parameters and precipitate properties were investigated in batch and continuous flow experiments. More than 90% of P removal was obtained from both undiluted fresh and hydrolyzed urines by mixing with RO brine (1:1, v/v) at a pH over 9.0. Around 2.58 and 1.24 Kg of precipitates could be recovered from 1 m3 hydrolyzed and fresh urine, respectively, and the precipitated solids contain 8.1-19.0% of P, 10.3-15.2% of Ca, 3.7-5.0% of Mg and 0.1-3.5% of ammonium nitrogen. Satisfactory P removal performance was also achieved in a continuous flow precipitation reactor with a hydraulic retention time of 3-6 h. RO brine could be considered as urinal and toilet flush water despite of a marginally higher precipitation tendency than tap water. This study provides a widely available, low - cost and efficient precipitant for P recovery in urban areas, which will make P recovery from urine more economically attractive.


Asunto(s)
Fósforo/química , Fósforo/aislamiento & purificación , Sales (Química)/química , Orina/química , Aguas Residuales/química , Filtración , Humanos , Masculino , Nitrógeno/análisis , Ósmosis , Fósforo/análisis , Sales (Química)/análisis , Agua/química , Purificación del Agua
8.
J Dairy Sci ; 99(9): 6927-6936, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27344382

RESUMEN

A disregarded nutritional feature of cheeses is their high acid-forming potential when ingested, which is associated with deleterious effects on consumers' health. This work aimed to characterize the acid-forming potential of a blue-veined cheese during manufacturing to identify the main steps of the process involved in this phenomenon. Sampling was performed on 3 batches at 10 steps of the cheese-making process: reception of raw milk, pasteurization, maturation of milk, coagulation, stirring, draining of the curds, and 4 ripening stages: 21, 28, 42, and 56d. The acid-forming potential of each sample was evaluated by (1) the calculation of the potential renal acid load (PRAL) index (considering protein, Cl, P, Na, K, Mg, and Ca contents), and (2) its organic anion content (lactate and citrate), considered as alkalinizing elements. Draining and salting were identified as the main steps responsible for generation of the acid-forming potential of cheese. The draining process induced an increase in the PRAL index from 1.2mEq/100g in milk to 10.4mEq/100g in drained curds due to the increase in dry matter and the loss of alkaline minerals into the whey. The increase in PRAL value (20.3mEq/100g at d 56) following salting resulted from an imbalance between the strong acidogenic elements (Cl, P, and proteins) and the main alkalinizing ones (Na and Ca). Particularly, Cl had a major effect on the PRAL value. Regarding organic anions, draining induced a loss of 93% of the citrate content in initial milk. The lactate content increased as fermentation occurred (1,297.9mg/100g in drained curds), and then decreased during ripening (519.3mg/100g at d 56). This lactate level probably helps moderate the acidifying potential of end products. Technological strategies aimed at limiting the acid-forming potential of cheeses are proposed and deserve further research to evaluate their nutritional relevance.


Asunto(s)
Queso/análisis , Manipulación de Alimentos/métodos , Sales (Química)/análisis , Animales , Calcio/análisis , Cloro/análisis , Ácido Cítrico/análisis , Análisis de los Alimentos , Concentración de Iones de Hidrógeno , Ácido Láctico/análisis , Magnesio/análisis , Leche/química , Proteínas de la Leche/análisis , Pasteurización , Fósforo/análisis , Potasio/análisis , Sodio/análisis
9.
Nat Prod Res ; 30(9): 1009-16, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26469871

RESUMEN

Ethanol production by fermentation is strongly dependent on media composition. Specific nutrients, such as trace elements, vitamins and nitrogen will affect the physiological state and, consequently, the fermentation performance of the micro-organism employed. The purpose of this study has been to assess the highest ethanol production by a minimal medium, instead of the more complex nutrients supplementation used during alcoholic fermentation. All fermentation tests were carried out using a microwell plate reader to monitor the processes. Two Saccharomyces cerevisiae strains (NCYC 2826 and NCYC 3445) were tested using three nitrogen sources, supplied with different vitamin and salts. The results show that solutions made of urea phosphate, KCl, MgSO4·7H2O, Ca-panthothenate, biotin allowed an ethanol yield of 22.9 and 23.4 g/L for strain NCYC 2826 and NCYC 3445, respectively, representing 90 and 92% of the theoretical yield. All tests were carried out using glucose as common reference carbon source.


Asunto(s)
Medios de Cultivo , Etanol/metabolismo , Fermentación , Saccharomyces cerevisiae/metabolismo , Sulfato de Amonio/metabolismo , Glucosa/metabolismo , Nitrógeno/metabolismo , Sales (Química)/análisis , Sales (Química)/metabolismo , Urea/metabolismo , Vitaminas/análisis , Vitaminas/metabolismo
11.
Dent Mater J ; 34(2): 270-9, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25753080

RESUMEN

Enamel and dentin particles were added to an experimental 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-based one-step adhesive to react for 30 s. After enamel and dentin reactants were analyzed using X-ray diffraction (XRD) and phosphorus-31 nuclear magnetic resonance ((31)P NMR) techniques, curve-fitting analysis was performed on the (31)P NMR spectra of enamel and dentin reactants. By varying the molar ratio of calcium chloride to MDP, a series of three types of MDP-Ca salts were synthesized. The molecular species of calcium salts of MDP (MDP-Ca salts) produced by decalcification of enamel or dentin were determined based on the XRD and (31)P NMR analysis results of these three types of synthesized MDP-Ca salts. Curve-fitting analysis showed that enamel and dentin developed several types of MDP-Ca salts and amorphous dicalcium phosphate dihydrate (DCPD) during decalcification. The molecular species of MDP-Ca salts produced by enamel and dentin were mono-calcium salts of MDP monomer and MDP dimer. In addition, dentin produced a di-calcium of MDP dimer.


Asunto(s)
Calcio/análisis , Metacrilatos/química , Dentina/química , Imagen por Resonancia Magnética , Fósforo , Sales (Química)/análisis , Desmineralización Dental/diagnóstico , Difracción de Rayos X/métodos
12.
Water Res ; 63: 135-46, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-25000196

RESUMEN

A new composite material based on alumina (Al2O3) modified by two surface nanocoatings - titanium dioxide (TiO2) and silver (Ag) - was studied for spa water disinfection. Regarding the most common microorganisms in bathing waters, two non-pathogenic bacteria Escherichia coli (Gram-negative) and Staphylococcus epidermidis (Gram positive) were selected as surrogates for bacterial contamination. The bactericidal properties of the Al2O3-TiO2-Ag material were demonstrated under various operating conditions encountered in spa water (temperature: 22-37 °C, presence of salt: CaCO3 or CaCl2, high oxygen content, etc.). Total removal of 10(8) CFU mL(-1) of bacteria was obtained in less than 10 min with 16 g L(-1) of material. Best results were observed for both conditions: a temperature of 37 °C and under aerobic condition; this latest favouring Reactive Oxygen Species (ROS) generation. The CaCO3 salt had no impact on the bactericidal activity of the composite material and CaCl2 considerably stabilized the silver desorption from the material surface thanks to the formation of AgCl precipitate. Preliminary tests of the Al2O3-TiO2-Ag bactericidal behaviour in a continuous water flow confirmed that 2 g L(-1) of material eliminated more than 90% of a 2.0 × 10(8) CFU mL(-1) bacterial mixture after one water treatment recycle and reached the disinfection standard recommended by EPA (coliform removal = 6 log) within 22 h.


Asunto(s)
Desinfectantes/farmacología , Desinfección/métodos , Escherichia coli/efectos de los fármacos , Nanopartículas del Metal/análisis , Nanocompuestos/análisis , Staphylococcus epidermidis/efectos de los fármacos , Óxido de Aluminio/farmacología , Balneología , Calor , Oxígeno/análisis , Sales (Química)/análisis , Plata/farmacología , Titanio/farmacología
13.
J Ethnopharmacol ; 148(1): 329-31, 2013 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-23567036

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Traditional medicines in the form of plants, animals and/or minerals are used by millions of South Africans. There is currently no data regarding the commonly used mineral elements thus the potential benefits or hazards of such products remain unclear. MATERIALS AND METHODS: Metal and crystalline salts were purchased from a rural market (Nongoma, Zululand, South Africa). Information regarding the colloquial name, price and weight was recorded. Energy dispersive X-ray spectroscopy (EDX) was used to quantatively determine the unknown salts. RESULTS: Six widely available salts were analyzed. Ndonya, as it is colloquially known, refers to two products which look identical to the untrained eye-one is dyed table salt and the other is hexavalent chromium. A further product used medicinally, although not widely available, was identified as iron chromite ore. CONCLUSIONS: The array of substances documented, ranging from benign to carcinogenic, stresses the importance of documenting components used in traditional medicine and confirms the necessity to regulate South Africa traditional medicine. Healthcare workers should be aware of the complexities of using such metal salt.


Asunto(s)
Medicinas Tradicionales Africanas , Sales (Química)/análisis , Cloruro de Amonio/análisis , Sulfato de Calcio/análisis , Sulfato de Cobre/análisis , Dicromato de Potasio/análisis , Permanganato de Potasio/análisis , Cloruro de Sodio/análisis , Sudáfrica , Azufre/análisis
14.
J Hazard Mater ; 178(1-3): 341-8, 2010 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-20149527

RESUMEN

More demanding legal regulations for the wastewater disposal and water scarcity make necessary wastewater reuse in the industry. In particular, textile industry generates large amounts of wastewater with a high concentration of pollutants. Even though present biological or physical-chemical treatments are broadly in place, the quality of the final effluent is not good enough to allow its direct reuse. Consequently, a complementary membrane process is required in order to improve wastewater characteristics. In this work, six NF membranes were tested at different volume concentration factors in order to select the most appropriate one. The main studied criteria were the permeate quality for its reuse in the textile processes and the minimum membrane fouling effect. The different results obtained for the tested membranes were explained by membrane characterization parameters as contact angle, roughness and size exclusion. Taking these factors into consideration, TFC-SR2 has shown the overall best results because of the high permeate flux and the minimum fouling (in terms of the normalised flux reduction).


Asunto(s)
Residuos Industriales/análisis , Membranas Artificiales , Textiles , Ultrafiltración , Eliminación de Residuos Líquidos/métodos , Algoritmos , Calcio/análisis , Color , Magnesio/análisis , Oxígeno/análisis , Permeabilidad , Proyectos Piloto , Sales (Química)/análisis
15.
J Environ Qual ; 38(3): 1320-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19398530

RESUMEN

The nutrient content of sludge produced by municipal water treatment works often far exceeds the requirements of nearby crops. Transporting sludge further afield is not always economically viable. This study reports on the potential to export large volumes of anaerobically digested municipal sewage sludge through turfgrass sod production. Hypotheses examined are that sludge loading rates far above recommendations based on crop nutrient removal (i) are possible without reducing turf growth and quality, (ii) do not cause an accumulation of N and P below the active root zone, (iii) can minimize soil loss through sod harvesting, and (iv) do not cause unacceptably high nitrate and salt leaching. An 8 Mg ha(-1) sludge control (the recommended limit) was compared with sludge rates of 0, 33, 67, and 100 Mg ha(-1) on a loamy, kaolinitic, mesic, Typic Eutrustox soil near Johannesburg, South Africa. Sludge application rates up to 67 Mg ha(-1) significantly improved turfgrass establishment rate and color. The ability of sods to remain intact during handling and transport improved as the sludge application rate increased to 33 Mg ha(-1) but deteriorated at higher rates. A sludge application rate of 100 Mg ha(-1) was needed to eliminate soil loss, but this rate was associated with unacceptably high N leaching losses. All our hypotheses were accepted for application rates not exceeding 33 Mg ha(-1) on the proviso that some soil loss was acceptable and that the leaching fraction was carefully managed during the first 2 mo after sludge application.


Asunto(s)
Nitrógeno/análisis , Pennisetum/crecimiento & desarrollo , Fósforo/análisis , Aguas del Alcantarillado , Suelo , Administración de Residuos/métodos , Nitratos/análisis , Sales (Química)/análisis , Suelo/análisis , Sudáfrica , Agua/análisis , Contaminantes Químicos del Agua/análisis
16.
Huan Jing Ke Xue ; 30(1): 231-6, 2009 Jan.
Artículo en Chino | MEDLINE | ID: mdl-19353886

RESUMEN

A new remediation method for petroleum-salt contaminated soil was proposed, in which wheat straw was applied to enhance salt leaching and meanwhile block salt upmovement along the soil capillary. It was shown that the existence of petroleum increased the surface hydrophobicity of soil and thus hindered the leaching process once the oil content was above 1.5% (mass fraction). The application of 5% (mass fraction) wheat straw into the soil increased the efficiency of salt leaching from 3% to 25%. The effectiveness of wheat straw layer in inhibiting the salt upmovement along the soil capillary was also proven. Field test of this method was carried out in an area of 6400 m2, in which wheat straw layer of 5 cm was distributed in the depth of 25 cm. After 50 days, 80% of the testing area showed a normal soil electronic conductivity (soil EC <5 mS x cm(-1)) in contrast to 17% before leaching process. The concentrations of Na+ and Cl- were decreased from 1642.5 mg x kg(-1) and 1 301.2 mg x kg(-1) to 499.3 mg x kg(-1) and 433.8 mg x kg(-1), respectively. The remediated land upon the implementation of wheat straw gave a 72% of the regular wheat production obtained from the normal farmland, while the control land without wheat straw gave 12%. These results demonstrated the effectiveness and the high potential of using wheat straw for the salt leaching in remediation of petroleum-salt contaminated soil.


Asunto(s)
Productos Agrícolas/crecimiento & desarrollo , Petróleo/metabolismo , Contaminantes del Suelo/metabolismo , Suelo/análisis , Triticum , Biodegradación Ambiental , Contaminación Ambiental/prevención & control , Tallos de la Planta , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/metabolismo , Sales (Química)/análisis , Sales (Química)/metabolismo
17.
Huan Jing Ke Xue ; 30(1): 237-41, 2009 Jan.
Artículo en Chino | MEDLINE | ID: mdl-19353887

RESUMEN

A new bioaugmentation method utilizing wheat straw to enhance salt leaching and the subsequent petroleum biodegradation by consortia of bacteria and fungi was proposed. The present study aimed at the effects of wheat straw on the growth and the degradation behavior of E. cloacae and Cun. echinulata, the two species of the consortia. In the laboratory experiments, it was shown that the addition of 5% (mass fraction) straw led to an increase of biomass by 25- and 3-fold to the bacteria and fungi, respectively. The biodegradation ratio of total petroleum hydrocarbon (TPH) was elevated from 29.2% to 48.0% after 468 h treatment. The biodegradation ratio of alkane and aromatic hydrocarbons in petroleum were increased from 31.5% and 39.1%, to 55.7% and 55.9%, respectively. The field demonstration was carried in an area of 6400 m2, in which the bacteria and fungi were inoculated after salt leaching in the presence of wheat straw. The addition of wheat straw in the contaminated soil led to an increase by 158- and 9-fold to the bacteria and fungi, as compared to their counterpart in the controlland without wheat straw, at 25 days after the inoculation. The content of TPH was down to below 0.3% while the maximum biodegradation ratio of TPH reached 75% after 45 days treatment. These results demonstrated the effectiveness and high potential of the wheat straw enhanced bioaugmentation of petroleum-salt contaminated soil.


Asunto(s)
Petróleo/metabolismo , Microbiología del Suelo , Contaminantes del Suelo/metabolismo , Suelo/análisis , Triticum , Biodegradación Ambiental , Productos Agrícolas/crecimiento & desarrollo , Cunninghamella/crecimiento & desarrollo , Cunninghamella/metabolismo , Enterobacter cloacae/crecimiento & desarrollo , Enterobacter cloacae/metabolismo , Contaminación Ambiental/prevención & control , Tallos de la Planta , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/metabolismo , Sales (Química)/análisis , Sales (Química)/metabolismo
18.
Waste Manag ; 28(11): 2097-121, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18037284

RESUMEN

This work reviews strategies for the management of municipal solid waste incineration (MSWI) residues, particularly solid particles collected from flue gases. These tiny particles may be retained by different equipment, with or without additives (lime, activated carbon, etc.), and depending on the different possible combinations, their properties may vary. In industrial plants, the most commonly used equipment for heat recovery and the cleaning of gas emissions are: heat recovery devices (boiler, superheater and economiser); dry, semidry or wet scrubbers; electrostatic precipitators; bag filters; fabric filters, and cyclones. In accordance with the stringent regulations in force in developed countries, these residues are considered hazardous, and therefore must be treated before being disposed of in landfills. Nowadays, research is being conducted into specific applications for these residues in order to prevent landfill practices. There are basically two possible ways of handling these residues: landfill after adequate treatment or recycling as a secondary material. The different types of treatment may be grouped into three categories: separation processes, solidification/stabilization, and thermal methods. These residues generally have limited applications, mainly due to the fact that they tend to contain large quantities of soluble salts (NaCl, KCl, calcium compounds), significant amounts of toxic heavy metals (Pb, Zn, Cr, Cu, Ni, Cd) in forms that may easily leach out, and trace quantities of very toxic organic compounds (dioxin, furans). The most promising materials for recycling this residue are ceramics and glass-ceramic materials. The main purpose of the present paper is to review the published literature in this field. A range of studies have been summarized in a series of tables focusing upon management strategies used in various countries, waste composition, treatment processes and possible applications.


Asunto(s)
Contaminación del Aire/análisis , Contaminación del Aire/prevención & control , Incineración/métodos , Metales Pesados/análisis , Eliminación de Residuos/métodos , Eliminación de Residuos/normas , Administración de Residuos/métodos , Países Desarrollados , Dioxinas/análisis , Residuos de Medicamentos/análisis , Furanos/análisis , Gases/análisis , Residuos Peligrosos/efectos adversos , Sales (Química)/análisis , Administración de Residuos/normas
19.
Waste Manag ; 28(10): 1977-82, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-17881210

RESUMEN

This study evaluated the feasibility of using municipal solid waste incinerator (MSWI) fly ash as acid soil amendment. In particular, changes in soil physicochemical properties and the potential environmental problems caused by the application of MSWI fly ash were investigated. The results showed that application of MSWI fly ash to the acid soil could raise the soil pH. The contents of rapidly available P and K, and slowly available K in the amended soil had a linear relationship with the addition ratio of MSWI fly ash. An addition of less than 20% of MSWI could raise the soil respiratory intensity after incubation for 3-5 days. Application of MSWI fly ash to the soil increased its content of water soluble salts and heavy metals, which could cause phytotoxicity in the plants. Therefore, the addition of MSWI fly ash to the soil should not be excessive, and less than 5-10% is an advisable addition level depending on the acidity of the soil and the plants growing on it.


Asunto(s)
Carbono/química , Fertilizantes , Material Particulado/química , Fósforo/análisis , Potasio/análisis , Suelo/análisis , Ceniza del Carbón , Ecosistema , Concentración de Iones de Hidrógeno , Incineración , Metales Pesados/análisis , Sales (Química)/análisis
20.
J Dairy Sci ; 90(4): 1625-34, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17369202

RESUMEN

Natural cheese is the major ingredient utilized to manufacture process cheese. The objective of the present study was to evaluate the effect of natural cheese characteristics on the chemical and functional properties of process cheese. Three replicates of 8 natural (Cheddar) cheeses with 2 levels of calcium and phosphorus, residual lactose, and salt-to-moisture ratio (S/M) were manufactured. After 2 mo of ripening, each of the 8 natural cheeses was converted to 8 process cheese foods that were balanced for their composition, including moisture, fat, salt, and total protein. In addition to the standard compositional analysis (moisture, fat, salt, and total protein), the chemical properties (pH, total Ca, total P, and intact casein) and the functional properties [texture profile analysis (TPA), modified Schreiber melt test, dynamic stress rheometry, and rapid visco analysis] of the process cheese foods were determined. Natural cheese Ca and P, as well as S/M, significantly increased total Ca and P, pH, and intact casein in the process cheese food. Natural cheese Ca and P and S/M also significantly affected the final functional properties of the process cheese food. With the increase in natural cheese Ca and P and S/M, there was a significant increase in the TPA-hardness and the viscous properties of process cheese food, whereas the meltability of the process cheese food significantly decreased. Consequently, natural cheese characteristics such as Ca and P and S/M have a significant influence on the chemical and the final functional properties of process cheese.


Asunto(s)
Queso/análisis , Queso/normas , Tecnología de Alimentos , Calcio/análisis , Industria Lechera/métodos , Manipulación de Alimentos/métodos , Lactosa/análisis , Fósforo/análisis , Sales (Química)/análisis , Agua/análisis
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