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1.
The traditional olive oil extraction process generates a large amount of liquid by-product that could be recycled as an organic fertilizer. The aim of this 3-year field experiment was to assess the effects of olive mill wastewater (OMWW) application on yields of ryegrass, proteic pea, and clover crops and on soil properties. The following treatments were compared: OMWW at 80 m3 ha?1 (80_OMWW), OMWW at 120 m3 ha?1 (120_OMWW), and an unfertilized control (Contr).

The yields of ryegrass increased 40% and 41.6% compared to Contr, for 80_OMWW and 120_OMWW, respectively, while a significant enhancement was found at the lowest level of OMWW in proteic pea (27.0% increase). Clover showed a species-specific sensitiveness, but the OMWW applications increased the protein content 26.3% and 28.7% for 80_OMWW and 120_OMWW, respectively, in comparison with Contr.

The OMWW rates also enhanced the total organic content in the soil compared to the unfertilized control. At the end of the 3-year experiment, total extracted carbon and humified organic carbon were greater than the initial ones. The values of available phosphorus (P) and potassium (K) determined at the end of experiment in Contr were almost the same as those recorded at the beginning of the research, confirming that the increases found in 80_OMWW and 120_OMWW plots were due to the OMWW applications.

The findings suggest that repeated applications of OMWW could both sustain fodder crop performance and support soil fertility, with the possibility to recycle the organic amendment and reduce the risks of soil degradation.  相似文献   

2.
Extraction methods to determine olive oil phenols are not exhaustive. A procedure to test their effectiveness, based on the treatment of the extracted oil with 2 N HCl followed by analysis of phenols in the aqueous phase, has been developed. It was concluded, using this test, that 15-40% of phenols remained unextracted when the liquid/liquid extraction method with 80% methanol was applied. Solid phase extraction (C(18) cartridge) succeeded in retaining most of the phenols in the cartridge, but the recovery yield from the sorbent material was low. However, a new extraction method, based on the use of N,N-dimethylformamide (DMF) as an extraction solvent, achieved a complete extraction of phenols from oils. The proposed method requires a lower amount of oil, solvents, energy, and labor than the traditional ones. Because of the low concentration of phenols in the DMF extract, the highly sensitive electrochemical detector (EC) technique was studied. All of the phenols detected by the traditional UV detectors were also detected by EC using a coulometric array system. A rapid and complete analytical methodology of phenols in olive oil has been proposed based on coupling DMF extraction and EC detection.  相似文献   

3.
A process to obtain enriched antioxidant phenolic extracts from lettuce (baby, romaine, and iceberg cultivars) and chichory byproducts as a way to valorize these byproducts was developed. Two extraction protocols using water and methanol as solvent were used. Amberlite XAD-2 nonionic polymeric resin was used to purify the extracts. The extraction yield, phenolic content, and phenolic yield were evaluated as well as the antioxidant capacity of the extracts (DPPH, ABTS, and FRAP assays). Baby and romaine lettuce byproducts showed the highest water extract yields [27 and 26 g of freeze-dried extracts/kg of byproduct fresh weight (fw), respectively], whereas baby and iceberg lettuce showed highest methanol extract yields (31 and 23 g of freeze-dried extracts/kg of byproduct fw, respectively). Methanol extraction yielded a raw extract with a high phenolic content, the baby and chicory extracts being the richest with approximately 50 mg of phenolics/g of freeze-dried extract. Regarding the purified extracts, water extraction yielded a higher phenolic content, baby and chicory being also the highest with mean values of approximately 190 and 300 mg of phenolics/g of freeze-dried extract, respectively. Both raw and purified extracts from baby and chicory showed the higher antioxidant contents (DPPH, ABTS, and FRAP assays). The antioxidant capacity was linearly correlated with the phenolic content. The results obtained indicate that lettuce byproducts could be, from the industrial point of view, an interesting and cheap source of antioxidant phenolic extracts to funcionalize foodstuffs.  相似文献   

4.
The isolation and identification of a phytocomplex from olive mill waste waters (OMWW) was achieved. The isolated phytocomplex is made up of the following three phenolic compounds: hydroxytyrosol (3,4-DHPEA), tyrosol (p-HPEA) and the dialdehydic form of decarboxymethyl elenolic acid, linked with (3,4-dihydroxyphenyl)ethanol (3,4-DHPEA-EDA). The purification of this phytocomplex was reached by partial dehydration of the OMWW, followed by liquid-liquid extraction with ethyl acetate and middle pressure liquid chromatography (MPLC) on a Sephadex LH-20 column. The phytocomplex accounted for 6% of the total phenolic content of the OMWW. The phytocomplex and individual compounds were tested for antioxidant capacity by the oxygen radical absorbance capacity (ORAC) method. The ORAC phytocomplex produced 10,000 ORAC units/g dry weight, whereas the cellular antioxidant activity, measured by the cellular antioxidant activity in red blood cell (CAA-RBC) method, demonstrated that the phytocomplex and all of the components are able to permeate the cell membrane thus exhibiting antioxidant activity inside the red blood cells. Our phytocomplex could be employed in the formulation of fortified foods and nutraceuticals, with the goal to obtain substantial health protective effects due to the suitable combination of the component molecules.  相似文献   

5.
An environmentally friendly bioremediation system of olive oil mill wastewater (OMWW) is studied with respect to its physicochemical characteristics and degradation efficiency on major characteristic constituents. The method exploits the biochemical versatility of the dinitrogen fixing bacterium Azotobacter vinelandii (strain A) to grow in OMWW at the expense of its constituents and to transform it into an organic liquid fertilizer. The system eliminates the phytotoxic principles from OMWW and concomitantly enriches it with an agriculturally beneficial microbial consortium along with useful metabolites of the latter. The end product, branded "biofertilizer", is used as soil conditioner and liquid organic fertilizer. Growth of A. vinelandii in OMWW results in the decline of content of most of the compounds associated with phytotoxicity, and this is confirmed by the assessment of degradation yields. In parallel, during the process several other compounds noncommittally undergo degradation and biotransformation. More specifically, the biofertilization system is capable of achieving removal yields as high as 90 and 96% after 3 and 7 days of treatment, respectively. Statistical analysis of the results showed that between the periods of operation no significant difference occurs with respect to the degradation yield. Moreover, the degradation yield from 3 to 7 days of continuous operation of the system remains almost unaltered during 2 consecutive years.  相似文献   

6.
During olive oil production, large volumes of water are generated and subsequently discarded. Olives contain a variety of bioactive components, and some of them, according to their partition coefficients, end up in the water phase. The current investigation aimed at comparing different methods for the extraction of biologically active components of the olive mill waste waters (OMWW) and evaluating the in vitro antioxidant and anti-inflammatory activities of the resulting extracts. The results indicate that OMWW extracts are able to inhibit human LDL oxidation (a process involved in the pathogenesis of atherosclerosis) and to scavenge superoxide anions and hypochlorous acid at concentrations as low as 20 ppm. Finally, two of the three extracts also inhibited the production of leukotrienes by human neutrophils. The potency of the extracts depended on their degree of refinement: extracts containing only low molecular weight phenols were the most effective.  相似文献   

7.
Enzymatic release of phenolic compounds from pomace remaining from black currant (Ribes nigrum) juice production was examined. Treatment with each of the commercial pectinolytic enzyme preparations Grindamyl pectinase, Macer8 FJ, Macer8 R, and Pectinex BE, as well as treatment with Novozym 89 protease, significantly increased plant cell wall breakdown of the pomace. Each of the tested enzyme preparations except Grindamyl pectinase also significantly enhanced the amount of phenols extracted from the pomace. Macer8 FJ and Macer8 R decreased the extraction yields of anthocyanins, whereas Pectinex BE and Novozym 89 protease showed no effect. A decrease in pomace particle sizes from 500-1000 microm to <125 microm increased the phenol yields 1.6-5 times. Black currant pomace devoid of seeds gave significantly higher yields of phenols than pomace with seeds and seedless wine pomace. Four selected black currant pomace extracts all exerted a pronounced antioxidant activity against human LDL oxidation in vitro when tested at equimolar phenol concentrations of 7.5-10 microM.  相似文献   

8.
The total phenol and anthocyanin contents of black currant pomace and black currant press residue (BPR) extracts, extracted with formic acid in methanol or with methanol/water/acetic acid, were studied. Anthocyanins and other phenols were identified by means of reversed phase HPLC, and differences between the two plant materials were monitored. In all BPR extracts, phenol levels, determined by the Folin-Ciocalteu method, were 8-9 times higher than in the pomace extracts. Acid hydrolysis liberated a much higher concentration of phenols from the pomace than from the black currant press residue. HPLC analysis revealed that delphinidin-3-O-glucoside, delphinidin-3-O-rutinoside, cyanidin-3-O-glucoside, and cyanidin-3-O-rutinoside were the major anthocyanins and constituted the main phenol class ( approximately 90%) in both types of black currant tissues tested. However, anthocyanins were present in considerably lower amounts in the pomace than in the BPR. In accordance with the total phenol content, the antioxidant activity determined by scavenging of 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation, the ABTS(*)(+) assay, showed that BPR extracts prepared by solvent extraction exhibited significantly higher (7-10 times) radical scavenging activity than the pomace extracts, and BPR anthocyanins contributed significantly (74 and 77%) to the observed high radical scavenging capacity of the corresponding extracts.  相似文献   

9.
谷春梅  候春宇  程安玮 《核农学报》2021,35(7):1574-1582
为提高红豆和绿豆中酚类化合物的得率及抗氧化能力,本试验采取蒸汽爆破加工对红豆和绿豆进行预处理,研究不同爆破处理组红豆和绿豆中总酚、总黄酮的含量及其抗氧化活性,并分析了两者之间的关系。结果表明,蒸汽爆破处理后的原料结构破裂严重,形成大量的碎片物质,促进原料中活性成分与溶剂的接触可及性。与对照组(CK)相比,经爆破处理后,红豆、绿豆中总酚、总黄酮含量明显上升,0.5 MPa、60 s爆破条件下绿豆中总酚、总黄酮含量最高,分别为4.57和3.00 mg·g-1;而红豆中的总酚、总黄酮含量在0.75 MPa、60 s爆破条件下最高,分别为4.66和3.07 mg·g-1。红豆中的总酚、总黄酮的含量均高于绿豆(除0.5 MPa、60 s爆破处理组)。不同处理组中提取物的抗氧化活性与总酚及总黄酮的含量变化基本一致,红豆中总酚含量与DPPH自由基清除率之间的相关性最高(r=0.966),绿豆中总酚含量与FRAP还原能力的相关性最高(r=0.895)。本研究结果为蒸汽爆破适用于不同生物质及有效成分的提取提供了一定的理论指导,进一步拓展了爆破技术在食品加工业的应用范围。  相似文献   

10.
为明确广东石豆兰的抗氧化能力及抗氧化成分,以鳞茎为材料,以甲醇、乙醇、丙酮和乙酸乙酯为提取剂得到4种提取物,测定了4种提取物中总黄酮、总酚含量及其抗氧化活性,并分析了两者之间的关系。结果表明,石豆兰总酚含量高于总黄酮,乙醇为总酚和总黄酮2种物质的最佳提取溶剂;甲醇提取物对羟基自由基清除力和对Fe2+的螯合力最强,对DPPH自由基清除效果最差;丙酮提取物具有最强的总还原力和清除超氧阴离子的能力,而清除羟基自由基能力最弱;乙酸乙酯提取物清除DPPH自由基的能力最强,但总还原力、清除超氧阴离子的能力、Fe2+的螯合力最弱。此外,除了DPPH自由基外,其他4个抗氧化指标与总黄酮或总酚含量呈正相关(0.185<r<0.969),总还原力与总黄酮含量呈显著相关。本研究结果为广东石豆兰抗氧化物质的提取及进一步开发利用提供了参考依据。  相似文献   

11.
The antioxidant activity of oregano, parsley, olive mill wastewaters (OMWW), Trolox, and ethylenediaminetetraacetic acid (EDTA) was evaluated in bulk oils and oil-in-water (o/w) emulsions enriched with 5% tuna oil by monitoring the formation of hydroperoxides, hexanal, and t-t-2,4-heptadienal in samples stored at 37 degrees C for 14 days. In bulk oil, the order of antioxidant activity was, in decreasing order (p < 0.05), OMWW > oregano > parsley > EDTA > Trolox. The antioxidant activity in o/w emulsion followed the same order except that EDTA was as efficient an antioxidant as OMWW. In addition, the total phenolic content, the radical scavenging properties, the reducing capacity, and the iron chelating activity of OMWW, parsley, and oregano extracts were determined by the Folin-Ciocalteau, oxygen radical absorbance capacity, ferric reducing antioxidant power, and iron(II) chelating activity assays, respectively. The antioxidant activity of OMWW, parsley, and oregano in food systems was related to their total phenolic content and radical scavenging capacity but not to their ability to chelate iron in vitro. OMWW was identified as a promising source of antioxidants to retard lipid oxidation in fish oil-enriched food products.  相似文献   

12.
Assays comprising three probes for different mechanisms of antioxidant activity in food products have been modified to allow better comparison of the contributions of the different mechanisms to antioxidant capacity (AOC). Incorporation of a common format for oxygen radical absorbance capacity (ORAC), ferric reducing antioxidant power (FRAP), and iron(II) chelating activity (ICA) assays using 96-well microplates provides a comprehensive and high-throughput assessment of the antioxidant capacity of food extracts. The methods have been optimized for aqueous extracts and validated in terms of limit of quantification (LoQ), linearity, and precision (repeatability and intermediate reproducibility). In addition, FRAP and ORAC assays have been validated to assess AOC for lipophilic extracts. The relative standard deviation of repeatability of the methods ranges from 1.2 to 6.9%, which is generally considered to be acceptable for analytical measurement of AOC by in vitro methods. Radical scavenging capacity, reducing capacity, and iron chelating properties of olive mill wastewaters (OMWW), oregano, and parsley were assessed using the validated methods. OMWW showed the highest radical scavenging and reducing capacities, determined by ORAC and FRAP assays, respectively, followed by oregano and parsley. The ability to chelate Fe (2+) was, in decreasing order of activity ( p > 0.05) parsley congruent with oregano > OMWW. Total phenol content, determined by the Folin-Ciocalteu method, correlated to the radical scavenging and reducing capacities of the samples but not to their chelating properties. Results showed that the optimized high-throughput methods provided a comprehensive and precise determination of the AOC of lipophilic and hydrophilic food extracts in vitro.  相似文献   

13.
Total phenolic and tocopherol contents and free radical scavenging capability of wheat bran extracted using conventional and microwave-assisted solvent extraction methods were studied. Three different solvents (methanol, acetone, and hexane) were used in the conventional solvent extraction. Methanol was the most effective solvent, producing higher extraction yield (4.86%), total phenolic compound content (241.3 μg of catechin equivalent/g of wheat bran), and free radical scavenging capability (0.042 μmol of trolox equivalent/g of wheat bran) than either acetone or hexane. However, there was no significant difference in the total tocopherol contents (13.6–14.8 μg/g of wheat bran) among the three different solvent extraction methods. Microwave-assisted solvent extraction using methanol significantly increased the total phenolic compound content to 467.5 and 489.5 μg of catechin equivalent; total tocopherol content to 18.7 and 19.5 μg; and free radical scavenging capability to 0.064 and 0.072 μmol of trolox equivalent/g of wheat bran at extraction temperatures of 100 and 120°C, respectively. However, extraction yields of conventional methanol solvent and microwave-assisted methanol extractions at different temperatures were not significantly different.  相似文献   

14.
Pressurized liquid extraction (PLE) was used to extract anthocyanins from the freeze-dried skin of a highly pigmented red wine grape with six solvents at 50 degrees C, 10.1 MPa, and 3 x 5 min extraction cycles. Temperature (from 20 to 140 degrees C in 20 degrees C increments) effects on anthocyanin recovery by acidified water and acidified 60% methanol were also studied. Acidified methanol extracted the highest levels of total monoglucosides and total anthocyanins, whereas the solvent mixture (40:40:20:0.1 methanol/acetone/water HCl) extracted the highest levels of total phenolics and total acylated anthocyanins. Acidified water extracts obtained by PLE at 80-100 degrees C had the highest levels of total monoglucosides, total acylated anthocyanins, total anthocyanins, total phenolics, and ORAC values. Acidified methanol extracts obtained by PLE at 60 degrees C had the highest levels of total monoglucosides and total anthocyanins, whereas extracts obtained at 120 degrees C had the highest levels of total phenolics. High-temperature PLE (80-100 degrees C) using acidified water, an environmentally friendly solvent, was as effective as acidified 60% methanol in extracting anthocyanins from grape skins.  相似文献   

15.
Phenolic compounds are found in both free and bound forms in cereals. The majority is in the insoluble bound form, that is, bound to cell wall material, such as ferulic acid and its derivatives. The antioxidant properties of the phenolic compounds in grains are associated with the health benefits of grains and grain products. The extraction capacity of several solvent mixtures, for extracting free phenols from barley flours, and the possibility of employing a rapid automated solvent extraction method were studied. The extraction yield of each method was evaluated by correlating several spectrophotometric indices (absorption at 280, 320, and 370 nm and total phenolic compounds by the Folin-Ciocalteu method) with the antioxidant activities of the barley extracts (scavenging activity by the 2,2-diphenyl-1-picrylhydrazyl method). Interesting results were obtained when ethanol and acetone-based extraction mixtures were employed to extract free phenols. A comparison was made between alkaline and acid hydrolysis. The extraction yield of bound phenolic compounds increased when the digestion time for alkaline hydrolysis was prolonged.  相似文献   

16.
The objective of the study was to isolate and identify potential cancer preventive constituents from green onion based on the ability to induce quinone reductase (QR, a representative phase II enzyme) in murine hepatoma cells (Hepa 1c1c7). Crude nonpolar solvent extracts were prepared from freeze-dried green onion by sequential refluxing with hexane and then ethyl acetate, followed by liquid-liquid extraction. Active fractions were subjected to the Hepa 1c1c7 bioassay-guided steps of flash chromatography, thin layer chromatography (TLC), and high-pressure preparative liquid chromatography (HPLC) to afford pure isolates capable of inducing QR. Multiple fractions were active in inducing QR. Five pure compounds were isolated from active fractions and identified using spectroscopic methods; these were p-hydroxyphenethyl trans-ferulate (1), 5,6-dimethyl-2-pyridinecarboxylic acid (2), ferulic acid (3), 1-(6-hydroxy-[3]pyridyl)-propan-1-one (4), and N-trans-feruloyl 3-O-methyldopamine (5). p-Hydroxyphenethyl trans-ferulate (1) doubled QR specific activity in Hepa 1c1c7 cells at a level of 2.1 microg/mL (6.6 microM).  相似文献   

17.
Health benefits of fruits, vegetables, and red wine are attributed to anthocyanins and other phytochemicals. In this research, the extraction of phenolics from black currants was optimized using different SO(2) concentrations (28, 300, 700, 1100, and 1372 ppm), temperatures (6, 20, 40, 60, and 74 degrees C), and solvent to solid ratios (S/S) (6, 20, 40, 60, and 74 mL/g). Surface response methodology was used to optimize yields of anthocyanins and total phenolics, as well as their antiradical and antioxidant activities. The extraction of phenolics varied with the SO(2) concentration, S/S, and temperature. Maximum yields of total phenolics and anthocyanins were obtained at an SO(2) concentration of 1000-1200 ppm and 19 L of solvent/kg of milled frozen berries. The increase of extraction temperature increased the rate of extraction and, thus, times to reach equilibrium for the extraction of total phenolics and anthocyanins were reduced. However, for the extraction of anthocyanins it is recommended that temperatures of 30-35 degrees C be used, as higher temperatures will degrade these compounds. Antioxidant activity was affected by all three experimental variables evaluated; however, the main variable affecting it was S/S. The higher the S/S, the lower the antioxidant index.  相似文献   

18.
The extraction of cedarwood oil (CWO) using liquid carbon dioxide (LC-CO(2)) was investigated and compared to supercritical fluid extraction, including the effects of extraction pressure and length of extraction. The chemical composition of the extracts was monitored over the course of the extraction as well. The cumulative yields of CWO from cedarwood chips using 80 L of carbon dioxide varied very little treatment to treatment, with all temperature/pressure combinations yielding between 3.55 and 3.88% CWO, and the cumulative yields were statistically equivalent. The rate of extraction was highest under the supercritical extraction conditions (i.e., 100 degrees C and 6000 psi). Under the liquid CO(2) conditions (i.e., 25 degrees C), the extraction rates did not vary significantly with extraction pressure. However, there were differences in the chemical composition of the collected CWO. Extractions at 100 degrees C gave a much lower ratio of cedrol/cedrene than extractions at 25 degrees C. The highest ratio of cedrol/cedrene was obtained using 25 degrees C and 1500 psi. The use of subcritical water was also investigated for the extraction of CWO as well. Although some CWO was extracted using this method, the temperature/pressure combinations that gave the highest weight percentage yields also gave oils with an off odor while those combinations that gave a higher quality oil had very low yields. It appears that the high temperatures and acidic conditions cause a dehydration of the tertiary alcohol, cedrol, to its hydrocarbon analogue, cedrene, during CO(2) or pressurized water extractions of cedarwood.  相似文献   

19.
Squalene was identified by gas chromatography-mass spectrometry and high-performance liquid chromatography (HPLC) spiking analyses in the supercritical CO(2) extracts of freeze-dried abscisic leaves of Terminalia catappa L. When the freeze-dried abscisic, senescent, mature, and immature leaves and seeds were subjected to supercritical CO(2) extraction at 40 degrees C and 3000 psi and HPLC quantitation, squalene contents were 12.29, 2.42, 1.75, 0.9, and 0% in the extracts and corresponding to 1499, 451, 210, 65, and 0 microg/g in the freeze-dried sample, respectively. When the extracts were applied for antioxidative characterization by supplementation in an iron/ascorbate system with linoleic acid and in a pork fat storage system for inhibition of conjugated diene hydroperoxide (CDHP) formation or in a free radical scavenging system with 1,1-diphenyl-2-picryl-hydrazyl (DPPH), the extracts of leaves exhibited potent antioxidative and DPPH scavenging activities and increased with an increase of leaf maturity. However, the seed extracts only exhibited potent inhibition of CDHP formation and very low DPPH scavenging activity.  相似文献   

20.
A simple analytical method for the quantitative determination of phenols, flavones, and lignans in virgin olive oils was developed. The polar fraction was isolated from small amounts of oil sample (2.5 g) by solid-phase extraction (SPE) using diol-phase cartridges, and the extract was analyzed by reversed-phase HPLC coupled with diode array UV detection. Chromatographic separation of pinoresinol, cinnamic acid, and 1-acetoxypinoresinol was achieved. Repeatability (RSD < 6.5%), recovery (> 90%), and response factors for each identified component were determined. SPE on amino-phase cartridges was used for isolating acidic phenols and as an aid for phenol identification. For the first time, 2-(4-hydroxyphenyl)ethyl acetate was detected in olive oils. The aldehydic structure of the ligstroside aglycon was confirmed by NMR spectroscopy. The colorimetric determination of total o-diphenolic compounds by reaction with molybdate was consistent with their HPLC determination. Differences between results obtained by liquid-liquid extraction and SPE were not statistically significant.  相似文献   

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