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81.
An incubation experiment was conducted to evaluate the ameliorating role of two organic amendments—olive-mill solid wastes and compost from olive-mill solid wastes- in the ecological reclamation of a lead/Zn-mine tailing collected in southern Spain. Four enzymatic activities (dehydrogenase, β-glucosidase, urease and phosphatase) and soluble and AB-DTPA extractable Pb and Zn and were periodically determined. High concentrations of Pb (5394 mg kg?1) and Zn (9607 mg kg?1), mainly in insoluble forms, were recorded in the lead/zinc-mine tailing, as well as very low biochemical activity. Application of the compost from olive-mill solid waste stimulated microbial activity and the biogeochemical cycles into the mine tailing because of the initially increased dehydrogenase, β-glucosidase and urease activities, which tended to decline or remained constant during the incubation period. By contrast, these enzyme activities were scarcely affected by the incorporation of the olive-mill solid wastes because this olive-organic amendment contains extractable polyphenols (36 g kg?1), which inhibit these enzyme activities. Phosphatase activity was enhanced by the application of both olive-organic amendments, especially when the olive-mill solid waste was added to the mine tailing. Amounts of soluble and AB-DTPA-extractable Pb and Zn in the mine tailing were increased by the application of the olive-mill solid waste, and to a lesser degree, by the compost from this olive waste. This fact could restrict the use of these olive-organic amendements as useful materials in reclamation of lead/zinc-mine tailings. Nevertheless, the increases of available lead and zinc would represent an advantage where Pb/Zn-mine tailings are reclaimed by phytoextraction, effectively reducing the metal pollution in these mining wastes. 相似文献
82.
Gómez ME Igartuburu JM Pando E Luis FR Mourente G 《Journal of agricultural and food chemistry》2004,52(15):4791-4794
In this paper, we describe the study and characterization of the lipids from lees of Sherry wine, one of the main byproducts from the wine-making industry in the Jerez/Xeres/Sherry denomination of the origin zone in Jerez de la Frontera, Spain. The lipid content, extractability, classification, fatty acid composition, and its main chemical characteristics have been determined in order to evaluate their potential use as a food or food additive. 相似文献
83.
Encarna Cayuela Alicia Muñoz‐Mayor Francisco Vicente‐Agulló Elena Moyano Jose O. Garcia‐Abellan Maria T. Estañ Maria C. Bolarín 《植物养料与土壤学杂志》2007,170(4):479-484
Agricultural productivity is worldwide subjected to increasing salinity problems. Various strategies are applied to overcome the deleterious effects of salinity on plants. This study was conducted in order to determine whether drought pretreatment of seedlings or seed pretreatment with NaCl increases the long‐term salinity resistance of tomato (Solanum lycopersicum L.) and whether the adaptive response to salinity is accompanied by physiological changes throughout the plant‐growth cycle. When plants were pretreated at the five‐leaf growth stage, the plant dry weight was significantly higher in drought‐pretreated than in non‐pretreated plants after 50 d of salt treatment. The positive effect of drought pretreatment applied at the five‐leaf stage was maintained throughout the entire growth cycle, as fruit yield of drought‐pretreated plants was 40% higher than that of non‐pretreated plants at the end of the harvest period (150 d of 70 mM NaCl treatment). Moreover, the most productive plants maintained lower Na+ and Cl– accumulation in their leaves until the end of the growth cycle, which shows that adaptation is a long‐term response during which the plants adjust their physiology to the environmental conditions. Salt resistance was also improved through seed pretreatment with NaCl. In conclusion, drought pretreatment applied at the five‐leaf stage or seed pretreatment with NaCl provide an alternative way to enhance salt resistance in tomato, and the increase in yield is associated with physiological changes throughout the plant‐growth cycle. 相似文献
84.
Díaz P Señoráns FJ Reglero G Ibañez E 《Journal of agricultural and food chemistry》2002,50(22):6468-6472
An experimental design has been used to optimize the extraction of volatile compounds from summer truffle aroma (Tuber aestivum) by using headspace solid phase microextraction. The extracted compounds have been analyzed by gas chromatography with a flame ionization detector and by gas chromatography-mass spectrometry (GC-MS). In an attempt to develop an objective method to fully characterize truffle aroma, a fiber of medium polarity (for flavors) was used to avoid discrimination toward very nonpolar and polar volatile compounds. To optimize the extraction conditions, a response surface experimental design was applied considering three factors such as extraction temperature, equilibrium time, and extraction time. From the statistical analysis of the experimental design, it was possible to determine that the most important factor influencing the abundance of aroma compounds was the extraction temperature. Optimal extraction temperature was established at approximately 50 degrees C. By using GC-MS, it was possible to identify 37 compounds, most of them previously described as responsible for truffle aroma. 相似文献
85.
The 1997-1998 El-Niño Southern Oscillation was the most severe on record and dramatically impacted corals worldwide. However, the effect of this event on the associated community of reef organisms has received much less attention. The composition of the bryozoan assemblage from the coral reefs of Northern Bahia, Brazil were monitored annually from 1995 to 2000, allowing the investigation of the effects of this large-scale stressor on an important, diverse, yet understudied component of the coral reef system. Bryozoan samples (35 replicates/reef) were collected during April/May from four shallow bank reefs (10-40 m depth) located a few kilometres off the coast, together with measurements of the associated environmental parameters. Currently 157 species have been recorded from the study area, but significant reductions in density and diversity were apparent between pre- and post El-Niño Southern Oscillation (ENSO) years, multivariate analysis denoting significant changes in assemblage composition. A total of 61 species were unrecorded following the 1997-1998 ENSO event (22 species from 1997; 25 further species from 1998 and 14 more from 1999). These included several species endemic to Brazil, suggesting that the 1997-1998 ENSO has had a marked influence on the reef bryozoan community, resulting in the local extinction of several species. Bryozoan mortalities were probably initiated by elevated temperatures, but continued disappearance of species for 2 years after ENSO suggests other indirect factors are also influential. These results demonstrate that ENSO events can have severe long-term impacts on the biodiversity of coral reefs, with important conservation consequences. 相似文献
86.
In order to reduce nutrient wastes to the environment the supply should be in accordance to the demand for these. Two experiments were conducted to study and quantify the effect of temperature, irradiance, and plant age on the uptake of nitrate (NO3?), ammonium (NH4+), dihydrogen phosphate ion (H2PO4?), potassium (K+), calcium (Ca2+), magnesium (Mg2+), and sulfate (SO42). In the first experiment, various levels of temperature and irradiance were applied to plants in a growth chamber, while in the second experiment the uptake was studied along the crop season under greenhouse conditions. The uptake rates were calculated at 2-hour intervals through sampling the nutrient solution and analyzing it by inductively coupled plasma atomic emission spectrometry (ICP-AES). Increasing light and temperature enhance the uptake rates, while the rates decrease with plant age. Nitrogen absorption was similar during the day as during the night. No differences were found in the absorption of H2PO4?, K+, Ca2+, Mg2+, and SO42? between day and night. Nitrate absorption was found to have a positive correlation with the absorption of all the ions except for NH4+. 相似文献
87.
Lorenzo C Pardo F Zalacain A Alonso GL Salinas MR 《Journal of agricultural and food chemistry》2005,53(19):7609-7616
The red grapes co-winemaking effect on phenolic fraction and wine color has been studied for the first time, where Monastrell was comacerated and cofermentated with Cabernet Sauvignon and Merlot. Changes in the relative abundance of anthocyanins were observed as well as hyperchromic shifts at 530 and 620 nm; these effects remain constant after aging. Co-winemaking also favored copigmentation, giving way to more stable anthocyanins and facilitating their polymerization. With regard to color evolution, the mixture of Monastrell with Merlot grapes was more appropriate than with Cabernet Sauvignon for aging wines in oak barrels. The extent of copigmentation was more important in young wines than in aged wines. This is mainly due to the self-anthocyanin monomer reactions in the case of young wines, whereas in aged wines copigmentation is mainly due to the reaction between the anthocyanins and other polyphenolic cofactors. Discriminant analysis showed the possibility of differentiating wines according to the aging time and the type of wine, with color parameters (color intensity, OD 620 nm, and OD 520 nm) being the most important discrimination variables in the first case and petunidin-3-glucoside and peonidin-3-glucoside contents in the second case. 相似文献
88.
89.
Romero MP Tovar MJ Girona J Motilva MJ 《Journal of agricultural and food chemistry》2002,50(19):5349-5354
The HPLC phenolic profile of virgin olive oils obtained from young olive trees (Arbequina cv.) grown under different deficit irrigation strategies was studied. Deficit irrigation (RDI) did not affect all the phenolic compounds in the same way. Lignans, vanillic acid, vanillin, and the unknown phenolic compound named P24 increased in the oils from the most irrigated treatments. The secoiridoid derivatives and the unknown phenolic compound named P19 increased in the oils from the most stressed irrigation treatments. The period of growth where a water stress significantly affects the phenolic profile of oils was between pit hardening and the first stages of fruit growth and oil accumulation, independently of the water applied during the previous period to harvest. The phenolic profile and those parameters related to phenol content, oxidative stability, and the bitter index were significantly affected only in the most severe RDI strategies. Other strategies produced important savings in irrigation requirements and an increase in the water use efficiency without noticeably affecting the phenolic profile. 相似文献
90.
Marín A Ferreres F Tomás-Barberán FA Gil MI 《Journal of agricultural and food chemistry》2004,52(12):3861-3869
Sweet peppers (Capsicum annuum L.) cv. Vergasa have been studied at four maturity stages (immature green, green, immature red, and red). The individual phenolics (hydroxycinnamic acids and flavonoids), vitamin C (ascorbic acid and dehydroascorbic acid), and individual carotenoids were characterized and quantified. Five hydroxycinnamic derivatives and 23 flavonoids were characterized and quantified from the pericarp of sweet pepper by high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry. Identification was carried out by their UV spectra, chromatographic comparisons with authentic markers, identification of hydrolysis products, and tandem mass spectrometry analysis. Hydroxycinnamic derivatives, O-glycosides of quercetin, luteolin, and chrysoeriol, and a large number of C-glycosyl flavones have been characterized. Some of these compounds were found for the first time in nature. Clear differences in the individual and total phenolic content were detected between the different maturity stages. Immature green pepper had a very high phenolic content while green, immature red, and red ripe peppers showed a 4-5-fold reduction. Ascorbic acid was the main form of vitamin C, and its content increased as the pepper reached maturity. The red ripe stage had a relevant impact on the carotenoids content. Thus, immature green peppers showed the highest content of polyphenols, while red ripe fruits had the highest content of vitamin C and provitamin A. 相似文献