Production in large quantities of highly purified hydroxytyrosol from liquid-solid waste of two-phase olive oil processing or "Alperujo"     

Fernández-Bolaños J  Rodríguez G  Rodríguez R  Heredia A  Guillén R  Jiménez A 《Journal of agricultural and food chemistry》2002,50(23):6804-6811

The effect of hydrothermal treatment of two-phase olive waste (alperujo) on the solubilization of hydroxytyrosol was studied. Different conditions of saturated steam were assayed. A high amount of hydroxytyrosol was solubilized and increased with increasing steaming temperature and time, reaching 1.4-1.7 g/100 g of dry alperujo. The effect of acidic (H(2)SO(4)) and basic (NaOH) catalysts was also evaluated. Acid-catalyzed treatment was more effective at milder conditions, whereas the alkali-catalyzed conditions were not very suitable. In the present study, the extracted hydroxytyrosol was purified by means of a new, simple, and inexpensive chromatographic system, under international patent application (PCT/ES02/00058). From 1000 kg of alperujo, with 70% humidity, can be obtained approximately 4.5-5 kg of hydroxytyrosol. After a purification process, at least 3 kg of hydroxytyrosol, at 90-95% purity, would be obtained. The purified compound was identified by HPLC/UV and (1)H and (13)C NMR analyses, and its antioxidant activity was tested on refined olive oil without antioxidants by Rancimat method. The oxidative stability of refined olive oil was increased by a factor of 1.71 in the presence of 100 ppm of hydroxytyrosol.  相似文献   

The status of Gilberto Righis earthworm collection at the museum of São Paulo – Righi memorial: tropical ecology: The 7th international symposium on earthworm ecology · Cardiff · Wales · 2002     

Ana G. Moreno  Catalina C. Mischis 《Pedobiologia》2003,47(5-6):413-418

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Distribution and contents of phenolic compounds in eighteen Scandinavian berry species   总被引：1，自引：0，他引：1  

Määttä-Riihinen KR  Kamal-Eldin A  Mattila PH  González-Paramás AM  Törrönen AR 《Journal of agricultural and food chemistry》2004,52(14):4477-4486

Berries contain a wide range of phenolic compounds in different conjugated forms, a fact that makes their simultaneous analysis a difficult task. In this work, soluble and insoluble phenolic compounds were identified and quantified in 18 species of berries by reversed phase high-performance liquid chromatography combined with diode array detection. The analytical results and literature data were used for the identification of the predominant conjugated hydroxycinnamic acids, flavonol glycosides, and anthocyanins in berries from six families, viz. Grossulariaceae, Ericaceae, Rosaceae, Empetraceae, Elaeagnaceae, and Caprifoliaceae. The study showed distinctive similarities among berry species of the same family in the distribution of conjugated forms of phenolic compounds but differences in chromatographic profiles of conjugates and compositions of aglycones especially in the case of anthocyanins. The chromatographic profiles of chokeberry and the related sweet rowanberry (Rosaceae) were exceptionally similar. These data are informative to studies on the authenticity of berry raw materials as well as to those on the evaluation of berries as sources of phenolic compounds.  相似文献   

Antifeedant effects of marine halogenated monoterpenes   总被引：4，自引：0，他引：4  

Argandoña VH  Rovirosa J  San-Martín A  Riquelme A  Díaz-Marrero AR  Cueto M  Darias J  Santana O  Guadaño A  González-Coloma A 《Journal of agricultural and food chemistry》2002,50(24):7029-7033

In this work the antifeedant effects of the halogenated monoterpenes 1-13 were tested against several divergent insect species. These compounds have been isolated from Plocamium cartilagineum (6 was isolated as an acetyl derivative), except for 4, which was isolated from Pantoneura plocamioides. We have also included the semisynthetic derivatives 1a, 2a, and 7. Compounds 1, 1a, 2, 4, 5, 7, 8-10, and 13 were antifeedants against Leptinotarsa decemlineata with varying potencies. The aphids Myzus persicae and Ropalosiphum padi were strongly deterred in the presence of compounds 2, 12, and 13. This effect was correlated with the electronic recording of their probing behavior. Compounds 2 and 12 were toxic to L. decemlineata and had selective cytotoxicity to insect-derived Sf9 cells. None of the tested compounds showed phytotoxic effects. The antifeedant and cytotoxic effects of these compounds were compared with those of the polyhalogenated insecticide gamma-hexachlorocyclohexane (lindane).  相似文献   

Application of NMR spectroscopy and LC-NMR/MS to the identification of carbohydrates in beer     

Duarte IF  Godejohann M  Braumann U  Spraul M  Gil AM 《Journal of agricultural and food chemistry》2003,51(17):4847-4852

The application of LC-NMR/MS for the direct identification of carbohydrates in beer has been studied. Carbohydrates are major beer components, and their structural characterization by NMR alone is seriously hindered by strong spectroscopic overlap. Direct analysis of beer by LC-NMR/MS enables the rapid (1-2 h) identification of dextrins with degree of polymerization (DP) of up to nine monomers, with degassing being the only sample treatment required. Although the presence of alpha(1-->6) branching points is easily indicated by NMR for each subfraction separated by LC, difficulties arise for the unambiguous assignment of linear or branched forms of high DP dextrins. The two beer samples investigated in this work were found to have significantly different oligosaccharide compositions, reflecting the different production conditions employed. The use of hyphenated NMR for the rapid characterization of the carbohydrate composition of beers may be the basis of a useful tool for the quality control of beer.  相似文献   

Denitrification from an irrigated soil fertilized with pig slurry under Mediterranean conditions   总被引：3，自引：0，他引：3  

Vallejo  Antonio  Díez  José A.  López-Valdivia  Luís M.  Cartagena  María C.  Tarquis  Ana  Hernáiz  Pedro 《Biology and Fertility of Soils》2004,40(2):93-100

Under a Mediterranean climate, denitrification losses were quantified for 2 years on a sandy loam soil with an irrigated maize crop. The effect of pig slurry application at two different rates (165 and 495 kg N ha^–1, respectively, for PS1 and PS3) was compared with that of urea (U) applied at 165 kg N ha^–1 and with a control treatment (P0) without fertilizer. After application, the denitrification rate (DR) increased in PS1 and PS3 respect to P0 and decreased to the levels of the control treatment after 5 days. In July and August (the irrigation period) the DR increased considerably in all treatments with maximum values for the PS3 treatment (0.134 g N m^–2 day^–1 in the first year and 0.147 g N m^–2 day^–1 in the second year). The differences in DRs between each treatment could be explained by the pattern of water filled pore space, NO₃^– concentration of the soil solution and the soil temperature during the maize growing season. In the first year denitrification losses in the 0–10 cm layer were 1.90, 2.49, 2.87 and 4.00 g N m^–2 for P0, U, PS1 and PS3, respectively, while in the second year the losses were 1.21, 2.28, 2.47 and 3.42 g N m^–2. Finally, a simple predictive model (SOILN) was evaluated and found to give acceptable results.  相似文献   

Sweet basil (Ocimum basilicum L.) and potassium fertilization     

Bihter Çolak Esetlili  Bintuğ Öztürk  Özgür Çobanoğlu  Dilek Anaç 《Journal of plant nutrition》2016,39(1):35-44

The objective of the present study was to examine the effect of potassium (K) fertilization and soil texture on total yield (1st and 2nd cuttings) and yield components of sweet basil (Ocimum basilicum L.) A greenhouse pot experiment was conducted in a completely randomized statistical design. Basil growth was examined in two different textured soils under three different doses of K fertilization. Generally, for the basil grown under clay soil conditions, moderate amounts of K fertilization is proposed to be sufficient if higher linalool contents are wanted. However, if the growing conditions are sandy loam in texture, it is suggested that higher doses of K be used. Results also highlighted the contribution of second cut as an important cultural practice in the cultivation of an annual basil.  相似文献   

Characteristics of maize flour tortilla supplemented with ground Tenebrio molitor larvae.     

Erick D Aguilar-Miranda  Mercedes G López  Clara Escamilla-Santana  Ana P Barba de la Rosa 《Journal of agricultural and food chemistry》2002,50(1):192-195

The larva of the Tenebrio molitor, known as the yellow meal worm, is a plague of wheat and flours. Consumption of the raw insects is not well accepted because of their appearance. The objective of the present work was to grow T. molitor larvae under standard conditions, to analyze the chemical composition of the larvae powder, and to prepare supplemented maize tortillas. Protein and fat contents were performed with standard methods. Tenebrio larvae powder had a 58.4% protein content; this protein was rich in essential amino acids such as phenylalanine, tyrosine, and tryptophan; the found values satisfied those recommended by the Food and Agriculture Organization. Fatty acid composition was determined by GC-MS showing high contents of oleic acid and linoleic acid (19.8 and 8.51%, respectively). A large proportion of unsaturated fatty acids of longer chains was detected. Long-chain fatty acids having two or three double bonds have been claimed as highly beneficial to health. Tortillas supplemented with larvae powder had excellent consumer acceptance, and tortilla protein content increased by 2% as well as the amount of essential amino acids. These results show new ways to consume insects and at the same time increase the nutritional value of the original food products.  相似文献   

Optimization of solid-state enzymatic hydrolysis of chestnut using mixtures of alpha-amylase and glucoamylase     

López C  Torrado A  Guerra NP  Pastrana L 《Journal of agricultural and food chemistry》2005,53(4):989-995

Solid-state hydrolysis of starch present in chestnut was assayed in a single step with a mixture of a thermostable alpha-amylase and glucoamylase at three temperatures: 17 and 30 degrees C, for simultaneous hydrolysis and ethanol fermentation, and 70 degrees C, the optimal temperature for these enzymes. Total hydrolysis was only reached at the highest temperature, leading to a more concentrated hydrolysate than in submerged hydrolysis. Mass transfer limitations and starch retrogradation appear as the main causes for the incomplete hydrolysis of chestnut starch in solid-state operation at 17 and 30 degrees C. Even accepting that this limitation causes a 15% reduction of the yield of the hydrolysis with respect to the submerged process or the solid process at high temperature, solid-state hydrolysis at low temperatures seems to be adequate for simultaneous solid-state hydrolysis and fermentation processes.  相似文献   

Effects of land-use on Collembola diversity patterns in a Mediterranean landscape     

Jos Paulo Sousa  Maria Manuela da Gama  Cristina Pinto  Antnio Keating  Filipa Calha  Marco Lemos  Catarina Castro  Tiago Luz  Pedro Leito  Susana Dias 《Pedobiologia》2004,48(5-6):609-622

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